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Alpers CE. Seeing through the density of dense deposit disease. Kidney Int 2024; 105:929-931. [PMID: 38642992 DOI: 10.1016/j.kint.2024.02.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 02/28/2024] [Indexed: 04/22/2024]
Abstract
Little is known about what constitutes the dense deposits of dense deposit disease (DDD), apart from components of the complement pathway. This study presents the novel finding that large accumulations of apolipoprotein E are present in the deposits of DDD, as revealed by mass spectroscopy and confirmed by both confocal microscopy and immunohistochemistry. The findings suggest a new modality for diagnosis of DDD and introduce potential new mechanisms for understanding DDD pathophysiology.
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Affiliation(s)
- Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington Medical Center, Seattle, Washington, USA.
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2
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Barbour SJ, Coppo R, Er L, Pillebout E, Russo ML, Alpers CE, Fogo AB, Ferrario F, Jennette JC, Roberts IS, Cook HT, Ding J, Su B, Zhong X, Fervenza FC, Zand L, Peruzzi L, Lucchetti L, Katafuchi R, Shima Y, Yoshikawa N, Ichikawa D, Suzuki Y, Murer L, Wyatt RJ, Park C, Nelson RD, Narus JH, Wenderfer S, Geetha D, Daugas E, Monteiro RC, Nakatani S, Mastrangelo A, Nuutinen M, Koskela M, Weber LT, Hackl A, Pohl M, Pecoraro C, Tsuboi N, Yokoo T, Takafumi I, Fujimoto S, Conti G, Santoro D, Materassi M, Zhang H, Shi S, Liu ZH, Tesar V, Maixnerova D, Avila-Casado C, Bajema I, Barreca A, Becker JU, Comstock JM, Cornea V, Eldin K, Hernandez LH, Hou J, Joh K, Lin M, Messias N, Muda AO, Pagni F, Diomedi-Camassei F, Tokola H, D'Armiento M, Seidl M, Rosenberg A, Sannier A, Soares MF, Wang S, Zeng C, Haas M. Histologic and Clinical Factors Associated with Kidney Outcomes in IgA Vasculitis Nephritis. Clin J Am Soc Nephrol 2024; 19:438-451. [PMID: 38261310 PMCID: PMC11020428 DOI: 10.2215/cjn.0000000000000398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 01/18/2024] [Indexed: 01/24/2024]
Abstract
BACKGROUND Nephritis is a common manifestation of IgA vasculitis and is morphologically indistinguishable from IgA nephropathy. While MEST-C scores are predictive of kidney outcomes in IgA nephropathy, their value in IgA vasculitis nephritis has not been investigated in large multiethnic cohorts. METHODS Biopsies from 262 children and 99 adults with IgA vasculitis nephritis ( N =361) from 23 centers in North America, Europe, and Asia were independently scored by three pathologists. MEST-C scores were assessed for correlation with eGFR/proteinuria at biopsy. Because most patients ( N =309, 86%) received immunosuppression, risk factors for outcomes were evaluated in this group using latent class mixed models to identify classes of eGFR trajectories over a median follow-up of 2.7 years (interquartile range, 1.2-5.1). Clinical and histologic parameters associated with each class were determined using logistic regression. RESULTS M, E, T, and C scores were correlated with either eGFR or proteinuria at biopsy. Two classes were identified by latent class mixed model, one with initial improvement in eGFR followed by a late decline (class 1, N =91) and another with stable eGFR (class 2, N =218). Class 1 was associated with a higher risk of an established kidney outcome (time to ≥30% decline in eGFR or kidney failure; hazard ratio, 5.84; 95% confidence interval, 2.37 to 14.4). Among MEST-C scores, only E1 was associated with class 1 by multivariable analysis. Other factors associated with class 1 were age 18 years and younger, male sex, lower eGFR at biopsy, and extrarenal noncutaneous disease. Fibrous crescents without active changes were associated with class 2. CONCLUSIONS Kidney outcome in patients with biopsied IgA vasculitis nephritis treated with immunosuppression was determined by clinical risk factors and endocapillary hypercellularity (E1) and fibrous crescents, which are features that are not part of the International Study of Diseases of Children classification.
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Affiliation(s)
- Sean J. Barbour
- Division of Nephrology, University of British Columbia, Vancouver, British Columbia, Canada
- BC Renal, Vancouver, British Columbia, Canada
| | - Rosanna Coppo
- Fondazione Ricerca Molinette, Regina Margherita Hospital, Turin, Italy
| | - Lee Er
- BC Renal, Vancouver, British Columbia, Canada
| | | | - Maria Luisa Russo
- Fondazione Ricerca Molinette, Regina Margherita Hospital, Turin, Italy
| | - Charles E. Alpers
- Department of Laboratory Medicine and Pathology, University of Washington Medical Center, Seattle, Washington
| | - Agnes B. Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Franco Ferrario
- Department of Medicine and Surgery, IRCCS San Gerardo, University Milan Bicocca, Monza, Italy
| | - J. Charles Jennette
- Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Ian S.D. Roberts
- Department of Cellular Pathology, Oxford University Hospitals NHS FT, Oxford, United Kingdom
| | | | - Jie Ding
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Baige Su
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xuhui Zhong
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | | | - Ladan Zand
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota
| | - Licia Peruzzi
- Pediatric Nephrology Unit, Regina Margherita Children's Hospital, AOU Città della Salute della Scienza di Torino, Turin, Italy
| | - Laura Lucchetti
- Division of Nephrology, Bambino Gesù Children's Hospital–IRCCS, Rome, Italy
| | - Ritsuko Katafuchi
- Kidney Unit, National Hospital Organization Fukuokahigashi Medical Center, Fukuoka, Japan
| | - Yuko Shima
- Department of Pediatrics, Wakayama Medical University, Wakayama, Japan
| | - Norishige Yoshikawa
- Clinical Research Center, Takatsuki General Hospital, Wakayam Medical University, Takatsuki City, Japan
| | - Daisuke Ichikawa
- Division of Nephrology and Hypertension, Department of Internal Medicine, St. Marianna University School of Medicine, Kanagawa, Japan
| | - Yusuke Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Luisa Murer
- Pediatric Nephrology Dialysis and Transplant Unit, Department of Women's and Child's Health, Azienda Ospedaliera-University of Padova, Padua, Italy
| | - Robert J. Wyatt
- Department of Pediatrics, University of Tennessee Health Sciences Center, Memphis, Tennessee
| | - Catherine Park
- Department of Pediatrics, University of Tennessee Health Sciences Center, Memphis, Tennessee
| | - Raoul D. Nelson
- Division of Pediatric Nephrology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - JoAnn H. Narus
- Pediatrics Clinical Trials Office, University of Utah, Salt Lake City, Utah
| | - Scott Wenderfer
- Division of Pediatric Nephrology, University of British Columbia, Vancouver, British Columbia, Canada
- Texas Children's Hospital, Houston, Texas
| | - Duvuru Geetha
- Department of Medicine, Division of Nephrology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Eric Daugas
- Nephrology, Bichat Hospital, AP-HP, Paris, France
- INSERM U1149 and Université Paris Cité, Paris, France
| | - Renato C. Monteiro
- Centre for Research on Inflammation, Bichat Hospital, Inserm and Université Paris Cité, Paris, France
| | - Shinya Nakatani
- Department of Metabolism, Endocrinology and Molecular Medicine, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan
| | - Antonio Mastrangelo
- Pediatric Nephrology, Dialysis and Transplant Unit, Fondazione IRCC Ca’ Granda-Ospedale Maggiore Policlinico, Milan, Italy
| | - Matti Nuutinen
- Department of Children and Adolescents, Oulu University Hospital, Oulu, Finland
- PEDEGO Research Unit, Research Unit for Pediatrics, Dermatology, Clinical Genetics, Obstetrics and Gynecology, Medical Research Center Oulu (MRC Oulu), Oulu, Finland
| | - Mikael Koskela
- Department of Pediatric Nephrology and Transplantation, New Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Lutz T. Weber
- Pediatric Nephrology, Faculty of Medicine and University Hospital Cologne, Children's and Adolescents' Hospital, University of Cologne, Cologne, Germany
| | - Agnes Hackl
- Pediatric Nephrology, Faculty of Medicine and University Hospital Cologne, Children's and Adolescents' Hospital, University of Cologne, Cologne, Germany
| | - Martin Pohl
- Medical Center, Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Carmine Pecoraro
- Comitato Tecnico Scientifico per la Ricerca e Innovaziione, A.O. Santobono-Pausilipon, Naples, Italy
| | - Nobuo Tsuboi
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Takashi Yokoo
- Department of Nephrology and Hypertension, Jikei University School of Medicine, Tokyo, Japan
| | - Ito Takafumi
- Kidney Center, Department of Internal Medicine, Nephrology, Teikyo University School of Medicine, Teikyo University Chiba Medical Center, Chiba, Japan
| | - Shouichi Fujimoto
- Division of Dialysis, Department of Nephrology, University of Miyazaki Hospital, Miyazaki, Japan
| | - Giovanni Conti
- Pediatric Nephrology and Rheumatology Unit, AOU Policlinic G Martino, University of Messina, Messina, Italy
| | - Domenico Santoro
- Nephrology and Dialysis Unit AOU, G. Martino, University of Messina, Messina, Italy
| | - Marco Materassi
- Nephrology and Dialysis Unit, Meyer Children's Hospital, Florence, Italy
| | - Hong Zhang
- Renal Division, Peking University First Hospital, Beijing, China
| | - Sufang Shi
- Kidney Division, Department of Medicine, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
| | - Zhi-Hong Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Vladimir Tesar
- Department of Nephrology, 1st Faculty of Medicine and General University Hospital, Charles University, Prague, Czech Republic
| | - Dita Maixnerova
- Department of Nephrology, 1st Faculty of Medicine, General University Hospital, Prague, Czech Republic
| | | | - Ingeborg Bajema
- Department of Pathology and Medical Biology, University of Groningen, Groningen, The Netherlands
| | - Antonella Barreca
- Pathology Unit, Città della Salute e della Scienza di Torino University Hospital, Turin, Italy
| | - Jan U. Becker
- Institute of Pathology, University Hospital of Cologne, Cologne, Germany
| | | | - Virgilius Cornea
- Department of Pathology, University of Kentucky Medical Center, Lexington, Kentucky
| | - Karen Eldin
- Department of Pathology, Mass General Brigham, Salem Hospital, Salem, Massachusetts
| | | | - Jean Hou
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, California
| | - Kensuke Joh
- Department of Pathology, The Jikei University School of Medicine, Tokyo, Japan
| | - Mercury Lin
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, California
| | - Nidia Messias
- Department of Pathology, Washington University in Saint Louis, St. Louis, Missouri
| | | | - Fabio Pagni
- Department of Medicine and Surgery, IRCCS San Gerardo, University Milan Bicocca, Monza, Italy
| | | | - Heikki Tokola
- Pathology, University Oulu and Oulu University Hospital, Oulu, Finland
| | - Maria D'Armiento
- Pathology Section, Department of Public Health, School of Medicine, University of Naples Federico II, Naples, Italy
| | - Maximilian Seidl
- Medical Center-University of Freiburg and Faculty of Medicine, Institute for Surgical Pathology, University of Freiburg, Freiburg, Germany
| | - Avi Rosenberg
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Aurélie Sannier
- Department of Pathology, AP-HP, Hôpital Bichat, Université Paris Cité, Paris, France
| | - Maria Fernanda Soares
- Department of Cellular Pathology, Oxford University Hospitals NHS FT, Oxford, United Kingdom
| | - Suxia Wang
- Laboratory of Electron Microscopy, Pathological Center, Peking University First Hospital, Beijing, China
| | - Caihong Zeng
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Mark Haas
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, California
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Alpers CE. Antiphospholipid Antibodies (aPL) and Thrombotic Microangiopathy for the Diagnosis of aPL Nephropathy: You Can't Have One Without the Other. J Rheumatol 2024; 51:109-111. [PMID: 38302187 DOI: 10.3899/jrheum.2023-1096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Affiliation(s)
- Charles E Alpers
- C.E. Alpers, MD, Professor of Laboratory Medicine and Pathology, Nelson Fausto-Ann De Lancey Endowed Professor, University of Washington, Seattle, Washington, USA.
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Paueksakon P, Najafian B, Alpers CE, Fogo AB. AJKD Atlas of Renal Pathology: IgA-Dominant Infection-Related Glomerulonephritis. Am J Kidney Dis 2024; 83:e1-e2. [PMID: 38129071 DOI: 10.1053/j.ajkd.2023.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 05/10/2023] [Indexed: 12/23/2023]
Affiliation(s)
- Paisit Paueksakon
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University, Nashville, Tennessee
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, Washington
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, Washington
| | - Agnes B Fogo
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University, Nashville, Tennessee.
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Rheault MN, Alpers CE, Barratt J, Bieler S, Canetta P, Chae DW, Coppock G, Diva U, Gesualdo L, Heerspink HJL, Inrig JK, Kirsztajn GM, Kohan D, Komers R, Kooienga LA, Lieberman K, Mercer A, Noronha IL, Perkovic V, Radhakrishnan J, Rote W, Rovin B, Tesar V, Trimarchi H, Tumlin J, Wong MG, Trachtman H. Sparsentan versus Irbesartan in Focal Segmental Glomerulosclerosis. N Engl J Med 2023; 389:2436-2445. [PMID: 37921461 DOI: 10.1056/nejmoa2308550] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2023]
Abstract
BACKGROUND An unmet need exists for focal segmental glomerulosclerosis (FSGS) treatment. In an 8-week, phase 2 trial, sparsentan, a dual endothelin-angiotensin receptor antagonist, reduced proteinuria in patients with FSGS. The efficacy and safety of longer-term treatment with sparsentan for FSGS are unknown. METHODS In this phase 3 trial, we enrolled patients with FSGS (without known secondary causes) who were 8 to 75 years of age; patients were randomly assigned to receive sparsentan or irbesartan (active control) for 108 weeks. The surrogate efficacy end point assessed at the prespecified interim analysis at 36 weeks was the FSGS partial remission of proteinuria end point (defined as a urinary protein-to-creatinine ratio of ≤1.5 [with protein and creatinine both measured in grams] and a >40% reduction in the ratio from baseline). The primary efficacy end point was the estimated glomerular filtration rate (eGFR) slope at the time of the final analysis. The change in eGFR from baseline to 4 weeks after the end of treatment (week 112) was a secondary end point. Safety was also evaluated. RESULTS A total of 371 patients underwent randomization: 184 were assigned to receive sparsentan and 187 to receive irbesartan. At 36 weeks, the percentage of patients with partial remission of proteinuria was 42.0% in the sparsentan group and 26.0% in the irbesartan group (P = 0.009), a response that was sustained through 108 weeks. At the time of the final analysis at week 108, there were no significant between-group differences in the eGFR slope; the between-group difference in total slope (day 1 to week 108) was 0.3 ml per minute per 1.73 m2 of body-surface area per year (95% confidence interval [CI], -1.7 to 2.4), and the between-group difference in the slope from week 6 to week 108 (i.e., chronic slope) was 0.9 ml per minute per 1.73 m2 per year (95% CI, -1.3 to 3.0). The mean change in eGFR from baseline to week 112 was -10.4 ml per minute per 1.73 m2 with sparsentan and -12.1 ml per minute per 1.73 m2 with irbesartan (difference, 1.8 ml per minute per 1.73 m2; 95% CI, -1.4 to 4.9). Sparsentan and irbesartan had similar safety profiles, and the frequency of adverse events was similar in the two groups. CONCLUSIONS Among patients with FSGS, there were no significant between-group differences in eGFR slope at 108 weeks, despite a greater reduction in proteinuria with sparsentan than with irbesartan. (Funded by Travere Therapeutics; DUPLEX ClinicalTrials.gov number, NCT03493685.).
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Affiliation(s)
- Michelle N Rheault
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Charles E Alpers
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Jonathan Barratt
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Stewart Bieler
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Pietro Canetta
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Dong-Wan Chae
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Gaia Coppock
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Ulysses Diva
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Loreto Gesualdo
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Hiddo J L Heerspink
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Jula K Inrig
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Gianna M Kirsztajn
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Donald Kohan
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Radko Komers
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Laura A Kooienga
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Kenneth Lieberman
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Alex Mercer
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Irene L Noronha
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Vlado Perkovic
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Jai Radhakrishnan
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - William Rote
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Brad Rovin
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Vladimir Tesar
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Hernán Trimarchi
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - James Tumlin
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Muh Geot Wong
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
| | - Howard Trachtman
- From the Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis (M.N.R.); the Department of Laboratory Medicine and Pathology, University of Washington, Seattle (C.E.A.); the Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, United Kingdom (J.B.); Travere Therapeutics, San Diego, CA (S.B., U.D., J.K.I., R.K., W.R.); the Division of Nephrology, Columbia University Irving Medical Center, New York (P.C., J.R.); the Division of Nephrology, Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea (D.-W.C.); Penn Renal Electrolyte and Hypertension Perelman, University of Pennsylvania, Philadelphia (G.C.); the Nephrology, Dialysis, and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy (L.G.); the Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, the Netherlands (H.J.L.H.); the George Institute for Global Health (H.J.L.H., V.P.) and the Faculty of Medicine and Health (V.P.), University of New South Wales, Sydney, and the Department of Renal Medicine, Concord Repatriation General Hospital, and Concord Clinical School, University of Sydney, Concord, NSW (M.G.W.) - all in Australia; the Department of Medicine (Nephrology), Federal University of São Paulo (G.M.K.), and the Division of Nephrology, University of São Paulo (I.L.N.) - both in São Paulo; the Department of Internal Medicine, Division of Nephrology, School of Medicine, University of Utah, Salt Lake City (D.K.); Colorado Kidney Care, Denver (L.A.K.); Hackensack University Medical Center, Hackensack, NJ (K.L.); JAMCO Pharma Consulting, Stockholm (A.M.); the Division of Nephrology, Ohio State University Wexner Medical Center, Columbus (B.R.); Všeobecná fakultní nemocnice v Praze, Prague, Czech Republic (V.T.); the Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires (H. Trimarchi); the Renal Division, Emory University, Atlanta, and the NephroNet Clinical Trials Consortium, Lawrenceville - both in Georgia (J.T.); and the Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor (H. Trachtman)
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Rovin BH, Barratt J, Heerspink HJL, Alpers CE, Bieler S, Chae DW, Diva UA, Floege J, Gesualdo L, Inrig JK, Kohan DE, Komers R, Kooienga LA, Lafayette R, Maes B, Małecki R, Mercer A, Noronha IL, Oh SW, Peh CA, Praga M, Preciado P, Radhakrishnan J, Rheault MN, Rote WE, Tang SCW, Tesar V, Trachtman H, Trimarchi H, Tumlin JA, Wong MG, Perkovic V. Efficacy and safety of sparsentan versus irbesartan in patients with IgA nephropathy (PROTECT): 2-year results from a randomised, active-controlled, phase 3 trial. Lancet 2023; 402:2077-2090. [PMID: 37931634 DOI: 10.1016/s0140-6736(23)02302-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/11/2023] [Accepted: 10/13/2023] [Indexed: 11/08/2023]
Abstract
BACKGROUND Sparsentan, a novel, non-immunosuppressive, single-molecule, dual endothelin angiotensin receptor antagonist, significantly reduced proteinuria versus irbesartan, an angiotensin II receptor blocker, at 36 weeks (primary endpoint) in patients with immunoglobulin A nephropathy in the phase 3 PROTECT trial's previously reported interim analysis. Here, we report kidney function and outcomes over 110 weeks from the double-blind final analysis. METHODS PROTECT, a double-blind, randomised, active-controlled, phase 3 study, was done across 134 clinical practice sites in 18 countries throughout the Americas, Asia, and Europe. Patients aged 18 years or older with biopsy-proven primary IgA nephropathy and proteinuria of at least 1·0 g per day despite maximised renin-angiotensin system inhibition for at least 12 weeks were randomly assigned (1:1) to receive sparsentan (target dose 400 mg oral sparsentan once daily) or irbesartan (target dose 300 mg oral irbesartan once daily) based on a permuted-block randomisation method. The primary endpoint was proteinuria change between treatment groups at 36 weeks. Secondary endpoints included rate of change (slope) of the estimated glomerular filtration rate (eGFR), changes in proteinuria, a composite of kidney failure (confirmed 40% eGFR reduction, end-stage kidney disease, or all-cause mortality), and safety and tolerability up to 110 weeks from randomisation. Secondary efficacy outcomes were assessed in the full analysis set and safety was assessed in the safety set, both of which were defined as all patients who were randomly assigned and received at least one dose of randomly assigned study drug. This trial is registered with ClinicalTrials.gov, NCT03762850. FINDINGS Between Dec 20, 2018, and May 26, 2021, 203 patients were randomly assigned to the sparsentan group and 203 to the irbesartan group. One patient from each group did not receive the study drug and was excluded from the efficacy and safety analyses (282 [70%] of 404 included patients were male and 272 [67%] were White) . Patients in the sparsentan group had a slower rate of eGFR decline than those in the irbesartan group. eGFR chronic 2-year slope (weeks 6-110) was -2·7 mL/min per 1·73 m2 per year versus -3·8 mL/min per 1·73 m2 per year (difference 1·1 mL/min per 1·73 m2 per year, 95% CI 0·1 to 2·1; p=0·037); total 2-year slope (day 1-week 110) was -2·9 mL/min per 1·73 m2 per year versus -3·9 mL/min per 1·73 m2 per year (difference 1·0 mL/min per 1·73 m2 per year, 95% CI -0·03 to 1·94; p=0·058). The significant reduction in proteinuria at 36 weeks with sparsentan was maintained throughout the study period; at 110 weeks, proteinuria, as determined by the change from baseline in urine protein-to-creatinine ratio, was 40% lower in the sparsentan group than in the irbesartan group (-42·8%, 95% CI -49·8 to -35·0, with sparsentan versus -4·4%, -15·8 to 8·7, with irbesartan; geometric least-squares mean ratio 0·60, 95% CI 0·50 to 0·72). The composite kidney failure endpoint was reached by 18 (9%) of 202 patients in the sparsentan group versus 26 (13%) of 202 patients in the irbesartan group (relative risk 0·7, 95% CI 0·4 to 1·2). Treatment-emergent adverse events were well balanced between sparsentan and irbesartan, with no new safety signals. INTERPRETATION Over 110 weeks, treatment with sparsentan versus maximally titrated irbesartan in patients with IgA nephropathy resulted in significant reductions in proteinuria and preservation of kidney function. FUNDING Travere Therapeutics.
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Affiliation(s)
- Brad H Rovin
- Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, OH, USA.
| | - Jonathan Barratt
- Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, UK
| | - Hiddo J L Heerspink
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, Netherlands; The George Institute for Global Health, University of New South Wales, Sydney, NSW, Australia
| | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | | | - Dong-Wan Chae
- Department of Internal Medicine, Seoul Red Cross Hospital, Seoul, South Korea
| | | | - Jürgen Floege
- Division of Nephrology, RWTH Aachen University Hospital, Aachen, Germany
| | - Loreto Gesualdo
- Nephrology, Dialysis and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy
| | | | - Donald E Kohan
- Division of Nephrology, School of Medicine, University of Utah Health, Salt Lake City, UT, USA
| | | | | | - Richard Lafayette
- Division of Nephrology, Stanford University Medical Center, Stanford, CA, USA
| | - Bart Maes
- Department of Nephrology, AZ Delta, Roeselare, Belgium
| | - Robert Małecki
- Department of Nephrology, Międzyleski Specialist Hospital, Warsaw, Poland
| | | | - Irene L Noronha
- Division of Nephrology, University of Sao Paulo, Sao Paulo, Brazil
| | - Se Won Oh
- Department of Internal Medicine, Korea University Anam Hospital, Korea University College of Medicine, Seoul, South Korea
| | - Chen Au Peh
- Royal Adelaide Hospital and University of Adelaide, Adelaide, SA, Australia
| | - Manuel Praga
- Research Institute Hospital 12 de Octubre (i+12), Madrid, Spain; Department of Medicine, Complutense University, Madrid, Spain
| | | | - Jai Radhakrishnan
- Division of Nephrology, Columbia University Irving Medical Center, New York, NY, USA
| | - Michelle N Rheault
- Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis, MN, USA
| | | | - Sydney C W Tang
- Division of Nephrology, Department of Medicine, School of Clinical Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Vladimir Tesar
- Department of Nephrology, General University Hospital, Charles University, Prague, Czechia
| | - Howard Trachtman
- Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Hernán Trimarchi
- Nephrology Service, British Hospital of Buenos Aires, Buenos Aires, Argentina
| | - James A Tumlin
- Renal Division, Emory University, Atlanta, GA, USA; NephroNet Clinical Trials Consortium, Atlanta, GA, USA
| | - Muh Geot Wong
- Department of Renal Medicine, Concord Repatriation General Hospital, Concord, NSW, Australia; Concord Clinical School, University of Sydney, Concord, NSW, Australia
| | - Vlado Perkovic
- Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
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Danaher P, Hasle N, Nguyen ED, Hayward K, Rosenwasser N, Alpers CE, Reed RC, Okamura DM, Baxter SK, Jackson SW. Single cell spatial transcriptomic profiling of childhood-onset lupus nephritis reveals complex interactions between kidney stroma and infiltrating immune cells. bioRxiv 2023:2023.11.09.566503. [PMID: 38014158 PMCID: PMC10680641 DOI: 10.1101/2023.11.09.566503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Children with systemic lupus erythematosus (SLE) are at increased risk of developing kidney disease, termed childhood-onset lupus nephritis (cLN). Single cell transcriptomics of dissociated kidney tissue has advanced our understanding of LN pathogenesis, but loss of spatial resolution prevents interrogation of in situ cellular interactions. Using a technical advance in spatial transcriptomics, we generated a spatially resolved, single cell resolution atlas of kidney tissue (>400,000 cells) from eight cLN patients and two controls. Annotated cells were assigned to 35 reference cell types, including major kidney subsets and infiltrating immune cells. Analysis of spatial distribution demonstrated that individual immune lineages localize to specific regions in cLN kidneys, including myeloid cells trafficking to inflamed glomeruli and B cells clustering within tubulointerstitial immune hotspots. Notably, gene expression varied as a function of tissue location, demonstrating how incorporation of spatial data can provide new insights into the immunopathogenesis of SLE. Alterations in immune phenotypes were accompanied by parallel changes in gene expression by resident kidney stromal cells. However, there was little correlation between histologic scoring of cLN disease activity and glomerular cell transcriptional signatures at the level of individual glomeruli. Finally, we identified modules of spatially-correlated gene expression with predicted roles in induction of inflammation and the development of tubulointerstitial fibrosis. In summary, single cell spatial transcriptomics allows unprecedented insights into the molecular heterogeneity of cLN, paving the way towards more targeted and personalized treatment approaches.
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Menon R, Otto EA, Barisoni L, Melo Ferreira R, Limonte CP, Godfrey B, Eichinger F, Nair V, Naik AS, Subramanian L, D'Agati V, Henderson JM, Herlitz L, Kiryluk K, Moledina DG, Moeckel GW, Palevsky PM, Parikh CR, Randhawa P, Rosas SE, Rosenberg AZ, Stillman I, Toto R, Torrealba J, Vazquez MA, Waikar SS, Alpers CE, Nelson RG, Eadon MT, Kretzler M, Hodgin JB. Defining the molecular correlate of arteriolar hyalinosis in kidney disease progression by integration of single cell transcriptomic analysis and pathology scoring. medRxiv 2023:2023.06.14.23291150. [PMID: 37398386 PMCID: PMC10312894 DOI: 10.1101/2023.06.14.23291150] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Arteriolar hyalinosis in kidneys is an independent predictor of cardiovascular disease, the main cause of mortality in chronic kidney disease (CKD). The underlying molecular mechanisms of protein accumulation in the subendothelial space are not well understood. Using single cell transcriptomic data and whole slide images from kidney biopsies of patients with CKD and acute kidney injury in the Kidney Precision Medicine Project, the molecular signals associated with arteriolar hyalinosis were evaluated. Co-expression network analysis of the endothelial genes yielded three gene set modules as significantly associated with arteriolar hyalinosis. Pathway analysis of these modules showed enrichment of transforming growth factor beta / bone morphogenetic protein (TGFβ / BMP) and vascular endothelial growth factor (VEGF) signaling pathways in the endothelial cell signatures. Ligand-receptor analysis identified multiple integrins and cell adhesion receptors as over-expressed in arteriolar hyalinosis, suggesting a potential role of integrin-mediated TGFβ signaling. Further analysis of arteriolar hyalinosis associated endothelial module genes identified focal segmental glomerular sclerosis as an enriched term. On validation in gene expression profiles from the Nephrotic Syndrome Study Network cohort, one of the three modules was significantly associated with the composite endpoint (> 40% reduction in estimated glomerular filtration rate (eGFR) or kidney failure) independent of age, sex, race, and baseline eGFR, suggesting poor prognosis with elevated expression of genes in this module. Thus, integration of structural and single cell molecular features yielded biologically relevant gene sets, signaling pathways and ligand-receptor interactions, underlying arteriolar hyalinosis and putative targets for therapeutic intervention.
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Keller MP, Hudkins KL, Shalev A, Bhatnagar S, Kebede MA, Merrins MJ, Davis DB, Alpers CE, Kimple ME, Attie AD. What the BTBR/J mouse has taught us about diabetes and diabetic complications. iScience 2023; 26:107036. [PMID: 37360692 PMCID: PMC10285641 DOI: 10.1016/j.isci.2023.107036] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023] Open
Abstract
Human and mouse genetics have delivered numerous diabetogenic loci, but it is mainly through the use of animal models that the pathophysiological basis for their contribution to diabetes has been investigated. More than 20 years ago, we serendipidously identified a mouse strain that could serve as a model of obesity-prone type 2 diabetes, the BTBR (Black and Tan Brachyury) mouse (BTBR T+ Itpr3tf/J, 2018) carrying the Lepob mutation. We went on to discover that the BTBR-Lepob mouse is an excellent model of diabetic nephropathy and is now widely used by nephrologists in academia and the pharmaceutical industry. In this review, we describe the motivation for developing this animal model, the many genes identified and the insights about diabetes and diabetes complications derived from >100 studies conducted in this remarkable animal model.
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Affiliation(s)
- Mark P. Keller
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Kelly L. Hudkins
- Department of Pathology, University of Washington Medical Center, Seattle, WA 98195, USA
| | - Anath Shalev
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Alabama at Birmingham, Birmingham, AL 35294, UK
| | - Sushant Bhatnagar
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Alabama at Birmingham, Birmingham, AL 35294, UK
| | - Melkam A. Kebede
- School of Medical Sciences, Faculty of Medicine and Health, Charles Perkins Centre, University of Sydney, Camperdown, Sydney, NSW 2006, Australia
| | - Matthew J. Merrins
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- William S. Middleton Memorial Veterans Hospital, Madison, WI 53705, USA
| | - Dawn Belt Davis
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- William S. Middleton Memorial Veterans Hospital, Madison, WI 53705, USA
| | - Charles E. Alpers
- Department of Pathology, University of Washington Medical Center, Seattle, WA 98195, USA
| | - Michelle E. Kimple
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- William S. Middleton Memorial Veterans Hospital, Madison, WI 53705, USA
| | - Alan D. Attie
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
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Barratt J, Rovin B, Wong MG, Alpers CE, Bieler S, He P, Inrig J, Komers R, Heerspink HJ, Mercer A, Noronha IL, Radhakrishnan J, Rheault MN, Rote W, Trachtman H, Trimarchi H, Perkovic V. IgA Nephropathy Patient Baseline Characteristics in the Sparsentan PROTECT Study. Kidney Int Rep 2023; 8:1043-1056. [PMID: 37180506 PMCID: PMC10166729 DOI: 10.1016/j.ekir.2023.02.1086] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/25/2023] [Accepted: 02/21/2023] [Indexed: 03/06/2023] Open
Abstract
Introduction Sparsentan is a novel single-molecule dual endothelin angiotensin receptor antagonist with hemodynamic and anti-inflammatory properties and is not an immunosuppressant. The ongoing phase 3 PROTECT trial examines sparsentan in adults with IgA nephropathy (IgAN). Methods The PROTECT trial (NCT03762850) is a multicenter, international, randomized, double-blind, parallel-group, active-controlled study. The efficacy and safety of sparsentan versus the active control irbesartan is being evaluated in adults with biopsy-proven IgAN and proteinuria ≥1.0 g/d despite maximized treatment with an angiotensin-converting enzyme inhibitor (ACEi) and/or angiotensin receptor blocker (ARB) for at least 12 weeks. Blinded and aggregated baseline characteristics are reported descriptively and compared to contemporary phase 3 trials with patients with IgAN. Results The primary analysis population includes 404 patients who were randomized and received study drug (median age, 46 years). Enrolled patients were from Europe (53%), Asia Pacific (27%), and North America (20%). Baseline median urinary protein excretion was 1.8 g/d. The range of estimated glomerular filtration rate (eGFR) was broad with the largest proportion of patients (35%) in chronic kidney disease (CKD) stage 3B. Before transitioning to study medication, mean systolic/diastolic blood pressure was 129/82 mm Hg, with the majority of patients (63.4%) receiving the maximum labeled ACEi or ARB dose. Patients in Asian versus non-Asian regions included a higher percentage of females, had lower blood pressures, and included lower proportions of patients with a history of hypertension and baseline antihypertensive treatment. Conclusions Patient enrollment in PROTECT, with differing racial backgrounds and across CKD stages, will allow for important characterization of the treatment effect of sparsentan in patients with IgAN with proteinuria at high risk of kidney failure.
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Affiliation(s)
- Jonathan Barratt
- Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, UK
| | - Brad Rovin
- Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Muh Geot Wong
- Department of Renal Medicine, Concord Repatriation General Hospital, Concord, New South Wales, Australia
- Concord Clinical School, University of Sydney, Concord, New South Wales, Australia
| | - Charles E. Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | | | - Ping He
- Travere Therapeutics Inc., San Diego, California, USA
| | - Jula Inrig
- Travere Therapeutics Inc., San Diego, California, USA
| | - Radko Komers
- Travere Therapeutics Inc., San Diego, California, USA
| | - Hiddo J.L. Heerspink
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
- The George Institute for Global Health, University of New South Wales, Sydney, New South Wales, Australia
| | | | - Irene L. Noronha
- Laboratory of Cellular, Genetic, and Molecular Nephrology, Division of Nephrology, University of São Paulo School of Medicine, São Paulo, Brazil
| | - Jai Radhakrishnan
- Division of Nephrology, Columbia University, New York, New York, USA
| | - Michelle N. Rheault
- Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - William Rote
- Travere Therapeutics Inc., San Diego, California, USA
| | - Howard Trachtman
- Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor, Michigan, USA
| | - Hernán Trimarchi
- The George Institute for Global Health, University of New South Wales, Sydney, New South Wales, Australia
- Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Vlado Perkovic
- The George Institute for Global Health, University of New South Wales, Sydney, New South Wales, Australia
- Faculty of Medicine and Health, University of New South Wales Sydney, Sydney, New South Wales, Australia
| | - PROTECT investigators17
- Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, UK
- Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Department of Renal Medicine, Concord Repatriation General Hospital, Concord, New South Wales, Australia
- Concord Clinical School, University of Sydney, Concord, New South Wales, Australia
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
- Travere Therapeutics Inc., San Diego, California, USA
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
- The George Institute for Global Health, University of New South Wales, Sydney, New South Wales, Australia
- JAMCO Pharma Consulting, Stockholm, Sweden
- Laboratory of Cellular, Genetic, and Molecular Nephrology, Division of Nephrology, University of São Paulo School of Medicine, São Paulo, Brazil
- Division of Nephrology, Columbia University, New York, New York, USA
- Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
- Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor, Michigan, USA
- Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
- Faculty of Medicine and Health, University of New South Wales Sydney, Sydney, New South Wales, Australia
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11
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Heerspink HJL, Radhakrishnan J, Alpers CE, Barratt J, Bieler S, Diva U, Inrig J, Komers R, Mercer A, Noronha IL, Rheault MN, Rote W, Rovin B, Trachtman H, Trimarchi H, Wong MG, Perkovic V. Sparsentan in patients with IgA nephropathy: a prespecified interim analysis from a randomised, double-blind, active-controlled clinical trial. Lancet 2023; 401:1584-1594. [PMID: 37015244 DOI: 10.1016/s0140-6736(23)00569-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/14/2023] [Accepted: 03/16/2023] [Indexed: 04/06/2023]
Abstract
BACKGROUND Sparsentan is a novel, non-immunosuppressive, single-molecule, dual endothelin and angiotensin receptor antagonist being examined in an ongoing phase 3 trial in adults with IgA nephropathy. We report the prespecified interim analysis of the primary proteinuria efficacy endpoint, and safety. METHODS PROTECT is an international, randomised, double-blind, active-controlled study, being conducted in 134 clinical practice sites in 18 countries. The study examines sparsentan versus irbesartan in adults (aged ≥18 years) with biopsy-proven IgA nephropathy and proteinuria of 1·0 g/day or higher despite maximised renin-angiotensin system inhibitor treatment for at least 12 weeks. Participants were randomly assigned in a 1:1 ratio to receive sparsentan 400 mg once daily or irbesartan 300 mg once daily, stratified by estimated glomerular filtration rate at screening (30 to <60 mL/min per 1·73 m2 and ≥60 mL/min per 1·73 m2) and urine protein excretion at screening (≤1·75 g/day and >1·75 g/day). The primary efficacy endpoint was change from baseline to week 36 in urine protein-creatinine ratio based on a 24-h urine sample, assessed using mixed model repeated measures. Treatment-emergent adverse events (TEAEs) were safety endpoints. All endpoints were examined in all participants who received at least one dose of randomised treatment. The study is ongoing and is registered with ClinicalTrials.gov, NCT03762850. FINDINGS Between Dec 20, 2018, and May 26, 2021, 404 participants were randomly assigned to sparsentan (n=202) or irbesartan (n=202) and received treatment. At week 36, the geometric least squares mean percent change from baseline in urine protein-creatinine ratio was statistically significantly greater in the sparsentan group (-49·8%) than the irbesartan group (-15·1%), resulting in a between-group relative reduction of 41% (least squares mean ratio=0·59; 95% CI 0·51-0·69; p<0·0001). TEAEs with sparsentan were similar to irbesartan. There were no cases of severe oedema, heart failure, hepatotoxicity, or oedema-related discontinuations. Bodyweight changes from baseline were not different between the sparsentan and irbesartan groups. INTERPRETATION Once-daily treatment with sparsentan produced meaningful reduction in proteinuria compared with irbesartan in adults with IgA nephropathy. Safety of sparsentan was similar to irbesartan. Future analyses after completion of the 2-year double-blind period will show whether these beneficial effects translate into a long-term nephroprotective potential of sparsentan. FUNDING Travere Therapeutics.
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Affiliation(s)
- Hiddo J L Heerspink
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, Netherlands; The George Institute for Global Health, University of New South Wales, Sydney, NSW, Australia.
| | | | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Jonathan Barratt
- Department of Cardiovascular Sciences, University of Leicester General Hospital, Leicester, UK
| | - Stewart Bieler
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, Groningen, Netherlands
| | | | - Jula Inrig
- Travere Therapeutics, San Diego, CA, USA
| | | | | | - Irene L Noronha
- Laboratory of Cellular, Genetic, and Molecular Nephrology, Division of Nephrology, University of São Paulo School of Medicine, São Paulo, Brazil
| | - Michelle N Rheault
- Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis, MN, USA
| | | | - Brad Rovin
- Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Howard Trachtman
- Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Hernán Trimarchi
- The George Institute for Global Health, University of New South Wales, Sydney, NSW, Australia; Nephrology Service, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Muh Geot Wong
- Department of Renal Medicine, Concord Repatriation General Hospital, Concord, NSW, Australia; Concord Clinical School, University of Sydney, Concord, NSW, Australia
| | - Vlado Perkovic
- The George Institute for Global Health, University of New South Wales, Sydney, NSW, Australia; Faculty of Medicine & Health, University of New South Wales Sydney, Sydney, NSW, Australia
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12
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Jackson SW, Alpers CE. Lupus nephritis transcriptomics across space and time. Kidney Int 2022; 102:694-696. [PMID: 36150761 DOI: 10.1016/j.kint.2022.06.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 06/24/2022] [Indexed: 11/17/2022]
Abstract
Current immunosuppression regimens for lupus nephritis are incompletely effective, placing patients at risk for poor long-term outcomes. This emphasizes the need to dissect pathogenic mechanisms in lupus nephritis, to inform the development of targeted therapies. In this issue of Kidney International, Parikh et al. performed transcriptomic analysis of pretreatment and posttreatment protocol kidney biopsies, segregated into glomerular and tubulointerstitial compartments, to identify candidate molecular pathways distinguishing treatment responders and nonresponders.
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Affiliation(s)
- Shaun W Jackson
- Seattle Children's Research Institute, Seattle, Washington, USA; Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington, USA; Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA.
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Lomax-Browne HJ, Medjeral-Thomas NR, Barbour SJ, Gisby J, Han H, Bomback AS, Fervenza FC, Cairns TH, Szydlo R, Tan SJ, Marks SD, Waters AM, Appel GB, D'Agati VD, Sethi S, Nast CC, Bajema I, Alpers CE, Fogo AB, Licht C, Fakhouri F, Cattran DC, Peters JE, Cook HT, Pickering MC. Association of Histologic Parameters with Outcome in C3 Glomerulopathy and Idiopathic Immunoglobulin-Associated Membranoproliferative Glomerulonephritis. Clin J Am Soc Nephrol 2022; 17:994-1007. [PMID: 35777834 PMCID: PMC9269630 DOI: 10.2215/cjn.16801221] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 05/16/2022] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND OBJECTIVES C3 glomerulopathy and idiopathic Ig-associated membranoproliferative GN are kidney diseases characterized by abnormal glomerular complement C3 deposition. These conditions are heterogeneous in outcome, but approximately 50% of patients develop kidney failure within 10 years. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS To improve identification of patients with poor prognosis, we performed a detailed analysis of percutaneous kidney biopsies in a large cohort of patients. Using a validated histologic scoring system, we analyzed 156 native diagnostic kidney biopsies from a retrospective cohort of 123 patients with C3 glomerulopathy and 33 patients with Ig-associated membranoproliferative GN. We used linear regression, survival analysis, and Cox proportional hazards models to assess the relationship between histologic and clinical parameters with outcome. RESULTS Frequent biopsy features were mesangial expansion and hypercellularity, glomerular basement membrane double contours, and endocapillary hypercellularity. Multivariable analysis showed negative associations between eGFR and crescents, interstitial inflammation, and interstitial fibrosis/tubular atrophy. Proteinuria positively associated with endocapillary hypercellularity and glomerular basement membrane double contours. Analysis of second native biopsies did not demonstrate associations between immunosuppression treatment and improvement in histology. Using a composite outcome, risk of progression to kidney failure associated with eGFR and proteinuria at the time of biopsy, cellular/fibrocellular crescents, segmental sclerosis, and interstitial fibrosis/tubular atrophy scores. CONCLUSIONS Our detailed assessment of kidney biopsy data indicated that cellular/fibrocellular crescents and interstitial fibrosis/tubular atrophy scores were significant determinants of deterioration in kidney function.
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Affiliation(s)
- Hannah J Lomax-Browne
- Department for Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College London, London, United Kingdom
| | - Nicholas R Medjeral-Thomas
- Department for Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College London, London, United Kingdom
| | - Sean J Barbour
- Division of Nephrology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jack Gisby
- Department for Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College London, London, United Kingdom
| | - Heedeok Han
- Department of Medicine, Division of Nephrology, Columbia University Irving Medical Center, New York, New York
| | - Andrew S Bomback
- Department of Medicine, Division of Nephrology, Columbia University Irving Medical Center, New York, New York
| | | | - Thomas H Cairns
- West London Renal and Transplant Centre, Imperial College Healthcare NHS Trust, London, United Kingdom
| | - Richard Szydlo
- Department for Immunology and Inflammation, Centre for Haematology, Imperial College London, London, United Kingdom
| | - Sven-Jean Tan
- Department of Nephrology, The Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - Stephen D Marks
- Department of Paediatric Nephrology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom.,National Institute for Health Research Great Ormond Street Hospital Biomedical Research Centre, University College London Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Aoife M Waters
- Department of Paediatric Nephrology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Gerald B Appel
- Department of Medicine, Division of Nephrology, Columbia University Irving Medical Center, New York, New York
| | - Vivette D D'Agati
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York
| | - Sanjeev Sethi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Cynthia C Nast
- Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, California
| | - Ingeborg Bajema
- Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Christoph Licht
- Division of Nephrology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Fadi Fakhouri
- Service of Nephrology and Hypertension, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Daniel C Cattran
- Toronto General Research Institute, Division of Nephrology, University of Toronto, Toronto, Ontario, Canada
| | - James E Peters
- Department for Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College London, London, United Kingdom
| | - H Terence Cook
- Department for Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College London, London, United Kingdom
| | - Matthew C Pickering
- Department for Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College London, London, United Kingdom
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14
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Tuttle KR, Agarwal R, Alpers CE, Bakris GL, Brosius FC, Kolkhof P, Uribarri J. Molecular Mechanisms and Therapeutic Targets for Diabetic Kidney Disease. Kidney Int 2022; 102:248-260. [PMID: 35661785 DOI: 10.1016/j.kint.2022.05.012] [Citation(s) in RCA: 97] [Impact Index Per Article: 48.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 04/29/2022] [Accepted: 05/10/2022] [Indexed: 12/12/2022]
Abstract
Diabetic kidney disease has a high global disease burden and substantially increases risk of kidney failure and cardiovascular events. Despite treatment, there is substantial residual risk of disease progression with existing therapies. Therefore, there is an urgent need to better understand the molecular mechanisms driving diabetic kidney disease to help identify new therapies that slow progression and reduce associated risks. Diabetic kidney disease is initiated by diabetes-related disturbances in glucose metabolism, which then trigger other metabolic, hemodynamic, inflammatory, and fibrotic processes that contribute to disease progression. This review summarizes existing evidence on the molecular drivers of diabetic kidney disease onset and progression, focusing on inflammatory and fibrotic mediators-factors that are largely unaddressed as primary treatment targets and for which there is increasing evidence supporting key roles in the pathophysiology of diabetic kidney disease. Results from recent clinical trials highlight promising new drug therapies, as well as a role for dietary strategies, in treating diabetic kidney disease.
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Affiliation(s)
- Katherine R Tuttle
- Providence Medical Research Center, Providence Health Care, Spokane, Washington, USA; Institute of Translational Health Sciences, Kidney Research Institute, and Nephrology Division, University of Washington, Seattle, Washington, USA.
| | - Rajiv Agarwal
- Nephrology Division, Indiana University School of Medicine, Indianapolis, Indiana, USA; Nephrology Division, VA Medical Center, Indianapolis, Indiana, USA
| | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | - George L Bakris
- American Heart Association Comprehensive Hypertension Center at the University of Chicago Medicine, Chicago, Illinois, USA
| | - Frank C Brosius
- Department of Medicine, College of Medicine, University of Arizona, Tucson, Arizona, USA; Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA; Department of Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Peter Kolkhof
- Cardiovascular Precision Medicines, Pharmaceuticals, Research & Development, Bayer AG, Wuppertal, Germany
| | - Jaime Uribarri
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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15
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Cervantes J, Kramer F, Yoshida K, Mun G, Alpers CE, Mullick AE, Kanter JE. Abstract 500: Silencing Apolipoprotein C3 Prevents Diabetic Kidney Disease And Atherosclerosis In A Mouse Model Of Type 2 Diabetes. Arterioscler Thromb Vasc Biol 2022. [DOI: 10.1161/atvb.42.suppl_1.500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Diabetes increases the risk of both cardiovascular disease and kidney disease. Notably, most of the excess cardiovascular risk in people with diabetes is in those with kidney disease. Apolipoprotein C3 (APOC3) is a small apolipoprotein that is elevated by insulin-insufficiency and regulates plasma triglyceride levels. To test if APOC3, and the dyslipidemia it represents, play a role in diabetic kidney disease (DKD) and associated atherosclerosis, we treated BTBR wildtype (WT) and leptin-deficient (OB; diabetic) mice with an antisense oligonucleotide (ASO) to APOC3 or a control ASO (cASO), all in the setting of human-like dyslipidemia (accomplished by administration of an ASO targeting the LDLR). APOC3 ASO treatment reduced triglycerides, triglyceride-rich lipoproteins. It prevented diabetes-accelerated atherosclerosis in the aortic sinus, brachiocephalic artery, and aorta (sinus lesion: 67926 ± 8486 μm
2
lesion in cASO-treated OB mice compared to 38589 ± 9507 μm
2
in APOC3 ASO-treated OB mice, p<0.05, n=12-15). The reduction in lesion size with APOC3 treatment was associated with fewer macrophages and reduced perilipin 2 staining (a marker for lipid droplet formation). In the kidney, diabetes resulted in a dramatic increase in glomerular hypertrophy, neutral lipid accumulation, APOC3, and APOE-accumulation, which APOC3 ASO-treatment attenuated. Furthermore, diabetes resulted in monocyte recruitment, macrophage accumulation, and macrophage lipid loading in the glomeruli, all of which was dramatically suppressed in the setting of APOC3 silencing (36% of glomerular macrophages were lipid loaded in OB cASO mice whereas only 9% were lipid loaded in APOC3-ASO treated mice, p<0.0001). The recruitment was driven by increased endothelial cell ICAM1 expression, but monocyte lipid loading may also contribute. Intriguingly, APOC3-ASO treatment reduced diabetes-associated urinary albumin creatinine ratio but did not affect it in non-diabetic mice (WT mice: 374 ± 71 μg albumin/mg creatinine, OB cASO mice: 4648 ± 1021 μg/mg and OB mice with APOC3 ASO: 2341 ± 439 μg/mg, p<0.05, n=12-14). Together, this suggests that targeting APOC3 and diabetic dyslipidemia might be beneficial for both diabetes-accelerated atherosclerosis and kidney disease.
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Affiliation(s)
| | | | | | - Grace Mun
- UNIVERSITY OF WASHINGTON, Seattle, WA
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16
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Patel J, Torrealba JR, Poggio ED, Bebiak J, Alpers CE, Grewenow SM, Toto RD, Eadon MT. Molecular Signatures of Diabetic Kidney Disease Hiding in a Patient with Hypertension-Related Kidney Disease: A Clinical Pathologic Molecular Correlation. Clin J Am Soc Nephrol 2022; 17:594-601. [PMID: 34911732 PMCID: PMC8993486 DOI: 10.2215/cjn.10350721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The Kidney Precision Medicine Project (KPMP) seeks to establish a molecular atlas of the kidney in health and disease and improve our understanding of the molecular drivers of CKD and AKI. Herein, we describe the case of a 66-year-old woman with CKD who underwent a protocol KPMP kidney biopsy. Her clinical history included well-controlled diabetes mellitus, hypertension, and proteinuria. The patient's histopathology was consistent with modest hypertension-related kidney injury, without overt diabetic kidney disease. Transcriptomic signatures of the glomerulus, interstitium, and tubular subsegments were obtained from laser microdissected tissue. The molecular signatures that were uncovered revealed evidence of early diabetic kidney disease adaptation and ongoing active tubular injury with enriched pathways related to mesangial cell hypertrophy, glycosaminoglycan biosynthesis, and apoptosis. Molecular evidence of diabetic kidney disease was found across the nephron. Novel molecular assays can supplement and enrich the histopathologic diagnosis obtained from a kidney biopsy.
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Affiliation(s)
- Jiten Patel
- Division of Nephrology, Department of Medicine, University of Texas Southwestern, Dallas, Texas
| | - Jose R. Torrealba
- Department of Pathology, University of Texas Southwestern, Dallas, Texas
| | - Emilio D. Poggio
- Department of Nephrology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio
| | - Jack Bebiak
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Charles E. Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Stephanie M. Grewenow
- Kidney Research Institute and Division of Nephrology, University of Washington, Seattle, Washington
| | - Robert D. Toto
- Division of Nephrology, Department of Medicine, University of Texas Southwestern, Dallas, Texas
| | - Michael T. Eadon
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
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17
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Abstract
The kidney biopsy is an essential tool for diagnosis of many kidney diseases. Obtaining an adequate biopsy sample with appropriate allocation for various studies is essential. Nephrologists should understand key lesions and their interpretation because these are essential elements underlying optimal approaches for interventions. This installment in the AJKD Core Curriculum in Nephrology will review these topics. We will first briefly discuss considerations for allocation and processing of kidney biopsies. We will then present in outline form the differential diagnoses of a spectrum of patterns of injury and consideration for interpretation of specific lesions. Lesions are presented according to anatomic site as glomerular, vascular, or tubulointerstitial. Native and transplant kidney biopsy lesions are included. These lesions and differential diagnoses and specific diseases are then linked to detailed clinicopathologic discussion of specific diseases presented in the AJKD Atlas of Kidney Pathology II. Correlation with immunofluorescence, electron microscopy, and clinical findings are emphasized to reach a differential diagnosis and the final diagnosis.
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Affiliation(s)
- Behzad Najafian
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Mark A Lusco
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Agnes B Fogo
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee.
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18
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Hudkins KL, Li X, Holland AL, Swaminathan S, Alpers CE. Regression of diabetic nephropathy by treatment with empagliflozin in BTBR ob/ob mice. Nephrol Dial Transplant 2021; 37:847-859. [PMID: 34865099 DOI: 10.1093/ndt/gfab330] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The SGLT2 inhibitor empagliflozin lowers blood glucose via reduced tubular reabsorption of filtered glucose and is an important new therapy for diabetic nephropathy (DN). This study tested whether treatment with empagliflozin would ameliorate proteinuria and the pathologic alterations of DN including podocyte number and integrity in the leptin deficient BTBR ob/ob mouse model of DN. METHODS Study cohorts included wild type BTBR mice, untreated diabetic BTBR ob/ob mice, and mice treated with empagliflozin for six weeks after development of established DN at 18 weeks of age. RESULTS Hyperglycemia, proteinuria, serum creatinine, accumulation of mesangial matrix and the extent of mesangiolysis were reversed with empagliflozin treatment. Treatment with empagliflozin resulted in increased podocyte number and podocyte density, improvement in the degree of podocyte foot process effacement and parietal epithelial cell activation. SGLT2 inhibition reduced renal oxidative stress, measured by urinary excretion of markers of RNA/DNA damage and in situ demonstration of decreased carbonyl oxidation. There was no discernable difference in accumulations of advanced glycation endproducts by immunohistochemistry. CONCLUSION The structural improvements seen in BTBR ob/ob mice treated with empagliflozin provide insight into potential long term benefits for humans with DN, for whom there is no comparable biopsy information to identify structural changes effected by SGLT2 inhibition. The findings suggest SGLT2 inhibition may ameliorate diabetic nephropathy through glucose lowering-dependent and -independent mechanisms that lead to podocyte restoration and delay or reversal of the disease progress.
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Affiliation(s)
- Kelly L Hudkins
- Department of Pathology, University of Washington, Seattle WA, USA
| | - Xianwu Li
- Department of Pathology, University of Washington, Seattle WA, USA
| | | | | | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle WA, USA
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19
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Huber TS, Berceli SA, Scali ST, Neal D, Anderson EM, Allon M, Cheung AK, Dember LM, Himmelfarb J, Roy-Chaudhury P, Vazquez MA, Alpers CE, Robbin ML, Imrey PB, Beck GJ, Farber AM, Kaufman JS, Kraiss LW, Vongpatanasin W, Kusek JW, Feldman HI. Arteriovenous Fistula Maturation, Functional Patency, and Intervention Rates. JAMA Surg 2021; 156:1111-1118. [PMID: 34550312 DOI: 10.1001/jamasurg.2021.4527] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Importance National initiatives have emphasized the use of autogenous arteriovenous fistulas (AVFs) for hemodialysis, but their purported benefits have been questioned. Objective To examine AVF usability, longer-term functional patency, and remedial procedures to facilitate maturation, manage complications, or maintain patency in the Hemodialysis Fistula Maturation (HFM) Study. Design, Setting, and Participants The HFM Study was a multicenter (n = 7) prospective National Institutes of Health National Institute of Diabetes and Digestive and Kidney Diseases cohort study performed to identify factors associated with AVF maturation. A total of 602 participants were enrolled (dialysis, kidney failure: 380; predialysis, chronic kidney disease [CKD]: 222) with AVF maturation ascertained for 535 (kidney failure, 353; CKD, 182) participants. Interventions All clinical decisions regarding AVF management were deferred to the individual centers, but remedial interventions were discouraged within 6 weeks of creation. Main Outcomes and Measures In this case series analysis, the primary outcome was unassisted maturation. Functional patency, freedom from intervention, and participant survival were summarized using Kaplan-Meier analysis. Results Most participants evaluated (n = 535) were men (372 [69.5%]) and had diabetes (311 [58.1%]); mean (SD) age was 54.6 (13.6) years. Almost two-thirds of the AVFs created (342 of 535 [64%]) were in the upper arm. The AVF maturation rates for the kidney failure vs CKD participants were 29% vs 10% at 3 months, 67% vs 38% at 6 months, and 76% vs 58% at 12 months. Several participants with kidney failure (133 [37.7%]) and CKD (63 [34.6%]) underwent interventions to facilitate maturation or manage complications before maturation. The median time from access creation to maturation was 115 days (interquartile range [IQR], 86-171 days) but differed by initial indication (CKD, 170 days; IQR, 113-269 days; kidney failure, 105 days; IQR, 81-137 days). The functional patency for the AVFs that matured at 1 year was 87% (95% CI, 83.2%-90.2%) and at 2 years, 75% (95% CI, 69.7%-79.7%), and there was no significant difference for those receiving interventions before maturation. Almost half (188 [47.5%]) of the AVFs that matured had further intervention to maintain patency or treat complications. Conclusions and Relevance The findings of this study suggest that AVF remains an accepted hemodialysis access option, although both its maturation and continued use require a moderate number of interventions to maintain patency and treat the associated complications.
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Affiliation(s)
- Thomas S Huber
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, University of Florida College of Medicine, Gainesville
| | - Scott A Berceli
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, University of Florida College of Medicine, Gainesville
| | - Salvatore T Scali
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, University of Florida College of Medicine, Gainesville
| | - Dan Neal
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, University of Florida College of Medicine, Gainesville
| | - Erik M Anderson
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, University of Florida College of Medicine, Gainesville
| | - Michael Allon
- Division of Nephrology, University of Alabama at Birmingham
| | - Alfred K Cheung
- Nephrology and Hypertension Division, University of Utah School of Medicine, Salt Lake City
| | - Laura M Dember
- Renal, Electrolyte and Hypertension Division, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Jonathan Himmelfarb
- Kidney Research Institute, Division of Nephrology, University of Washington, Seattle
| | | | - Miguel A Vazquez
- Division of Nephrology, University of Texas Southwestern, Dallas
| | | | | | - Peter B Imrey
- Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio
| | - Gerald J Beck
- Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio
| | - Alik M Farber
- Division of Vascular and Endovascular Surgery, Boston Medical Center, Boston, Massachusetts
| | - James S Kaufman
- Renal Section, Veterans Affairs New York Harbor Healthcare System, New York
| | - Larry W Kraiss
- Division of Vascular Surgery, University of Utah, Salt Lake City
| | | | - John W Kusek
- Division of Kidney, Urologic, and Hematologic Diseases, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Harold I Feldman
- Renal, Electrolyte and Hypertension Division, University of Pennsylvania Perelman School of Medicine, Philadelphia.,Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania Perelman School of Medicine, Philadelphia
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20
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Attie AD, Schueler KM, Keller MP, Mitok KA, Simonett SP, Hudkins KL, Mehrotra K, Graham MJ, Lee RG, Alpers CE. Reversal of hypertriglyceridemia in diabetic BTBR ob/ob mice does not prevent nephropathy. J Transl Med 2021; 101:935-941. [PMID: 33911188 PMCID: PMC9093019 DOI: 10.1038/s41374-021-00592-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 03/05/2021] [Accepted: 03/08/2021] [Indexed: 01/11/2023] Open
Abstract
The etiology of diabetic nephropathy in type 2 diabetes is multifactorial. Sustained hyperglycemia is a major contributor, but additional contributions come from the hypertension, obesity, and hyperlipidemia that are also commonly present in patients with type 2 diabetes and nephropathy. The leptin deficient BTBR ob/ob mouse is a model of type 2 diabetic nephropathy in which hyperglycemia, obesity, and hyperlipidemia, but not hypertension, are present. We have shown that reversal of the constellation of these metabolic abnormalities with leptin replacement can reverse the morphologic and functional manifestations of diabetic nephropathy. Here we tested the hypothesis that reversal specifically of the hypertriglyceridemia, using an antisense oligonucleotide directed against ApoC-III, an apolipoprotein that regulates the interactions of VLDL (very low density lipoproteins) with the LDL receptor, is sufficient to ameliorate the nephropathy of Type 2 diabetes. Antisense treatment resulted in reduction of circulating ApoC-III protein levels and resulted in substantial lowering of triglycerides to near-normal levels in diabetic mice versus controls. Antisense treatment did not ameliorate proteinuria or pathologic manifestations of diabetic nephropathy, including podocyte loss. These studies indicate that pathologic manifestations of diabetic nephropathy are unlikely to be reduced by lipid-lowering therapeutics alone, but does not preclude a role for such interventions to be used in conjunction with other therapeutics commonly employed in the treatment of diabetes and its complications.
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Affiliation(s)
- Alan D Attie
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA.
| | - Kathryn M Schueler
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Mark P Keller
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Kelly A Mitok
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Shane P Simonett
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Kelly L Hudkins
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Kunaal Mehrotra
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | | | | | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA.
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21
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Jacobs HM, Arkatkar T, Du SW, Scharping NE, Woods J, Li QZ, Hudkins KL, Alpers CE, Rawlings DJ, Jackson SW. TACI haploinsufficiency protects against BAFF-driven humoral autoimmunity in mice. Eur J Immunol 2021; 51:2225-2236. [PMID: 34146342 DOI: 10.1002/eji.202149244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/26/2021] [Accepted: 06/16/2021] [Indexed: 11/06/2022]
Abstract
Polymorphisms in TACI, a BAFF family cytokine receptor, are linked to diverse human immune disorders including common variable immunodeficiency (CVID) and systemic lupus erythematosus (SLE). Functional studies of individual variants show modest impacts on surface TACI expression and/or downstream signal transduction, indicating that relatively subtle variation in TACI activity can impact human B-cell biology. However, significant complexity underlies TACI biology, including both positive and negative regulation of physiologic and pathogenic B-cell responses. To model these contradictory events, we compared the functional impact of TACI deletion on separate models of murine SLE driven by T cell-independent and -dependent breaks in B-cell tolerance. First, we studied whether reduced surface TACI expression was sufficient to protect against progressive BAFF-mediated systemic autoimmunity. Strikingly, despite a relatively modest impact on surface TACI levels, TACI haploinsufficiency markedly reduced pathogenic RNA-associated autoantibody titers and conferred long-term protection from BAFF-driven lupus nephritis. In contrast, B cell-intrinsic TACI deletion exerted a limited impact of autoantibody generation in murine lupus characterized by spontaneous germinal center formation and T cell-dependent humoral autoimmunity. Together, these combined data provide new insights into TACI biology and highlight how TACI signals must be tightly regulated during protective and pathogenic B-cell responses.
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Affiliation(s)
| | | | - Samuel W Du
- Seattle Children's Research Institute, Seattle, WA, USA
| | | | | | - Quan-Zhen Li
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Kelly L Hudkins
- Departments of Laboratory Medicine and Pathology, Immunology and Pediatrics, University of Washington School of Medicine, Washington, WA, USA
| | - Charles E Alpers
- Departments of Laboratory Medicine and Pathology, Immunology and Pediatrics, University of Washington School of Medicine, Washington, WA, USA
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22
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de Boer IH, Alpers CE, Azeloglu EU, Balis UGJ, Barasch JM, Barisoni L, Blank KN, Bomback AS, Brown K, Dagher PC, Dighe AL, Eadon MT, El-Achkar TM, Gaut JP, Hacohen N, He Y, Hodgin JB, Jain S, Kellum JA, Kiryluk K, Knight R, Laszik ZG, Lienczewski C, Mariani LH, McClelland RL, Menez S, Moledina DG, Mooney SD, O'Toole JF, Palevsky PM, Parikh CR, Poggio ED, Rosas SE, Rosengart MR, Sarwal MM, Schaub JA, Sedor JR, Sharma K, Steck B, Toto RD, Troyanskaya OG, Tuttle KR, Vazquez MA, Waikar SS, Williams K, Wilson FP, Zhang K, Iyengar R, Kretzler M, Himmelfarb J. Rationale and design of the Kidney Precision Medicine Project. Kidney Int 2021; 99:498-510. [PMID: 33637194 PMCID: PMC8330551 DOI: 10.1016/j.kint.2020.08.039] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/08/2020] [Accepted: 08/14/2020] [Indexed: 02/07/2023]
Abstract
Chronic kidney disease (CKD) and acute kidney injury (AKI) are common, heterogeneous, and morbid diseases. Mechanistic characterization of CKD and AKI in patients may facilitate a precision-medicine approach to prevention, diagnosis, and treatment. The Kidney Precision Medicine Project aims to ethically and safely obtain kidney biopsies from participants with CKD or AKI, create a reference kidney atlas, and characterize disease subgroups to stratify patients based on molecular features of disease, clinical characteristics, and associated outcomes. An additional aim is to identify critical cells, pathways, and targets for novel therapies and preventive strategies. This project is a multicenter prospective cohort study of adults with CKD or AKI who undergo a protocol kidney biopsy for research purposes. This investigation focuses on kidney diseases that are most prevalent and therefore substantially burden the public health, including CKD attributed to diabetes or hypertension and AKI attributed to ischemic and toxic injuries. Reference kidney tissues (for example, living-donor kidney biopsies) will also be evaluated. Traditional and digital pathology will be combined with transcriptomic, proteomic, and metabolomic analysis of the kidney tissue as well as deep clinical phenotyping for supervised and unsupervised subgroup analysis and systems biology analysis. Participants will be followed prospectively for 10 years to ascertain clinical outcomes. Cell types, locations, and functions will be characterized in health and disease in an open, searchable, online kidney tissue atlas. All data from the Kidney Precision Medicine Project will be made readily available for broad use by scientists, clinicians, and patients.
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Affiliation(s)
- Ian H de Boer
- Department of Medicine, University of Washington, Seattle, Washington, USA.
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, Washington, USA
| | - Evren U Azeloglu
- Department of Medicine, Icahn School of Medicine at Mt. Sinai, New York, New York, USA
| | - Ulysses G J Balis
- Department of Pathology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Laura Barisoni
- Department of Pathology, Duke University, Durham, North Carolina, USA
| | - Kristina N Blank
- Department of Biostatistics, University of Washington, Seattle, Washington, USA
| | - Andrew S Bomback
- Department of Medicine, Columbia University, New York, New York, USA
| | - Keith Brown
- Patient Representative, Kidney Precision Medicine Project Steering Committee Member
| | - Pierre C Dagher
- Department of Medicine, Indiana University, Indianapolis, Indiana, USA
| | - Ashveena L Dighe
- Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Michael T Eadon
- Department of Medicine, Indiana University, Indianapolis, Indiana, USA
| | - Tarek M El-Achkar
- Department of Medicine, Indiana University, Indianapolis, Indiana, USA
| | - Joseph P Gaut
- Department of Pathology, Washington University School of Medicine, St. Louis, St. Louis, Missouri, USA
| | - Nir Hacohen
- Broad Institute, Cambridge, Massachusetts, USA
| | - Yongqun He
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | - Jeffrey B Hodgin
- Department of Pathology, University of Michigan, Ann Arbor, Michigan, USA
| | - Sanjay Jain
- Department of Medicine, Washington University School of Medicine, St. Louis, St. Louis, Missouri, USA
| | - John A Kellum
- Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Krzysztof Kiryluk
- Department of Medicine, Columbia University, New York, New York, USA
| | - Richard Knight
- American Association of Kidney Patients, Kidney Precision Medicine Project Patient Partner
| | - Zoltan G Laszik
- Department of Pathology, University of California, San Francisco, San Francisco, California, USA
| | - Chrysta Lienczewski
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Laura H Mariani
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Robyn L McClelland
- Department of Biostatistics, University of Washington, Seattle, Washington, USA
| | - Steven Menez
- Department of Medicine, Johns Hopkins Medicine, Baltimore, Maryland, USA
| | - Dennis G Moledina
- Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Sean D Mooney
- Department of Biomedical Informatics and Medical Education, University of Washington, Seattle, Washington, USA
| | - John F O'Toole
- Department of Nephrology and Hypertension, Cleveland Clinic, Cleveland, Ohio, USA
| | - Paul M Palevsky
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; Renal Section, Veterans Administration Pittsburgh Healthcare System, Pittsburgh, Pennsylvania, USA
| | - Chirag R Parikh
- Department of Medicine, Johns Hopkins Medicine, Baltimore, Maryland, USA
| | - Emilio D Poggio
- Department of Nephrology and Hypertension, Cleveland Clinic, Cleveland, Ohio, USA
| | | | - Matthew R Rosengart
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Minnie M Sarwal
- Department of Surgery, University of California, San Francisco, San Francisco, California, USA
| | - Jennifer A Schaub
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - John R Sedor
- Department of Nephrology and Hypertension, Cleveland Clinic, Cleveland, Ohio, USA
| | - Kumar Sharma
- Department of Medicine, UT Health San Antonio, San Antonio, Texas, USA
| | - Becky Steck
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Robert D Toto
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Olga G Troyanskaya
- Department of Computer Science, Princeton University, Princeton, New Jersey, USA
| | - Katherine R Tuttle
- Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Miguel A Vazquez
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Sushrut S Waikar
- Department of Medicine, Boston University Medical Center, Boston, Massachusetts, USA
| | - Kayleen Williams
- Department of Biostatistics, University of Washington, Seattle, Washington, USA
| | - Francis Perry Wilson
- Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Kun Zhang
- Institute for Genomic Sciences, University of California, San Diego, California, USA
| | - Ravi Iyengar
- Mount Sinai Institute for Systems Biomedicine, Mount Sinai, New York, New York, USA
| | - Matthias Kretzler
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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23
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Minnelli C, Riazy M, Ohashi R, Kowalewska J, Leca N, Najafian B, Smith KD, Nicosia RF, Alpers CE, Akilesh S. Early Transplant Arteriopathy in Kidney Transplantation. Transplant Proc 2021; 53:1554-1561. [PMID: 33962774 DOI: 10.1016/j.transproceed.2021.02.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 12/15/2020] [Accepted: 02/25/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND Early dysfunction of renal allografts may be associated with vascular injury, which raises the specter of active rejection processes that require medical intervention. In our practice, we have encountered patients who present with delayed graft function and demonstrate a unique pattern of endothelial cell injury that raises concern for rejection in their biopsy. Therefore, we sought to systematically determine the biopsy characteristics and outcome of these patients. METHODS During a 17-year period at the University of Washington in Seattle, United States, we identified 24 cases of a distinct arterial vasculopathy presenting in the first year posttransplantation. This early transplant arteriopathy (ETA) is characterized by endothelial cell swelling and intimal edema but without the intimal arteritis that defines vascular rejection. RESULTS Approximately 1% of transplant biopsies during the study period showed ETA, almost all of which were in deceased donor organs (96%), and most presented with delayed graft function (54%) or increased serum creatinine (38%) soon after transplantation (median 13 days; range, 5-139). In this study, 77% of patients were managed expectantly, with only 2 patients (7.6%) subsequently developing acute vascular rejection. Except for 1 patient who died, all patients had functioning allografts at 1 year follow-up. CONCLUSION Recognizing ETA and distinguishing it from vascular rejection is important to prevent over-treatment because most patients appear to recover allograft function rapidly with expectant management.
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Affiliation(s)
- Carrie Minnelli
- Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington
| | - Maziar Riazy
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington; Department of Pathology and Laboratory Medicine, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Ryuji Ohashi
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington; Department of Pathology, Nippon Medical School, Tokyo, Japan
| | - Jolanta Kowalewska
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington; Department of Pathology and Anatomy, Eastern Virginia Medical School, Norfolk, Virginia
| | - Nicolae Leca
- Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington
| | - Behzad Najafian
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Kelly D Smith
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Roberto F Nicosia
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Shreeram Akilesh
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington.
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24
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El-Achkar TM, Eadon MT, Menon R, Lake BB, Sigdel TK, Alexandrov T, Parikh S, Zhang G, Dobi D, Dunn KW, Otto EA, Anderton CR, Carson JM, Luo J, Park C, Hamidi H, Zhou J, Hoover P, Schroeder A, Joanes M, Azeloglu EU, Sealfon R, Winfree S, Steck B, He Y, D’Agati V, Iyengar R, Troyanskaya OG, Barisoni L, Gaut J, Zhang K, Laszik Z, Rovin BH, Dagher PC, Sharma K, Sarwal MM, Hodgin JB, Alpers CE, Kretzler M, Jain S. A multimodal and integrated approach to interrogate human kidney biopsies with rigor and reproducibility: guidelines from the Kidney Precision Medicine Project. Physiol Genomics 2021; 53:1-11. [PMID: 33197228 PMCID: PMC7847045 DOI: 10.1152/physiolgenomics.00104.2020] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Comprehensive and spatially mapped molecular atlases of organs at a cellular level are a critical resource to gain insights into pathogenic mechanisms and personalized therapies for diseases. The Kidney Precision Medicine Project (KPMP) is an endeavor to generate three-dimensional (3-D) molecular atlases of healthy and diseased kidney biopsies by using multiple state-of-the-art omics and imaging technologies across several institutions. Obtaining rigorous and reproducible results from disparate methods and at different sites to interrogate biomolecules at a single-cell level or in 3-D space is a significant challenge that can be a futile exercise if not well controlled. We describe a "follow the tissue" pipeline for generating a reliable and authentic single-cell/region 3-D molecular atlas of human adult kidney. Our approach emphasizes quality assurance, quality control, validation, and harmonization across different omics and imaging technologies from sample procurement, processing, storage, shipping to data generation, analysis, and sharing. We established benchmarks for quality control, rigor, reproducibility, and feasibility across multiple technologies through a pilot experiment using common source tissue that was processed and analyzed at different institutions and different technologies. A peer review system was established to critically review quality control measures and the reproducibility of data generated by each technology before their being approved to interrogate clinical biopsy specimens. The process established economizes the use of valuable biopsy tissue for multiomics and imaging analysis with stringent quality control to ensure rigor and reproducibility of results and serves as a model for precision medicine projects across laboratories, institutions and consortia.
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Affiliation(s)
| | | | - Rajasree Menon
- 2University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Blue B. Lake
- 3Jacobs School of Engineering, University of California, San Diego, California
| | - Tara K. Sigdel
- 4University of California San Francisco School of Medicine, San Francisco, California
| | | | - Samir Parikh
- 6Ohio State University College of Medicine, Columbus, Ohio
| | - Guanshi Zhang
- 7UT-Health San Antonio School of Medicine, San Antonio, Texas
| | - Dejan Dobi
- 4University of California San Francisco School of Medicine, San Francisco, California
| | - Kenneth W. Dunn
- 1Indiana University School of Medicine, Indianapolis, Indiana
| | - Edgar A. Otto
- 2University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Christopher R. Anderton
- 7UT-Health San Antonio School of Medicine, San Antonio, Texas,8Pacific Northwest National Laboratory, Richland, Washington
| | - Jonas M. Carson
- 9Schools of Medicine and Public Health, University of Washington, Seattle, Washington
| | - Jinghui Luo
- 2University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Chris Park
- 9Schools of Medicine and Public Health, University of Washington, Seattle, Washington
| | - Habib Hamidi
- 2University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Jian Zhou
- 12Princeton University, Princeton, New Jersey,14Columbia University School of Medicine, New York City, New York
| | - Paul Hoover
- 10Harvard University School of Medicine, Boston Massachusetts
| | - Andrew Schroeder
- 4University of California San Francisco School of Medicine, San Francisco, California
| | - Marianinha Joanes
- 4University of California San Francisco School of Medicine, San Francisco, California
| | | | - Rachel Sealfon
- 12Princeton University, Princeton, New Jersey,14Columbia University School of Medicine, New York City, New York
| | - Seth Winfree
- 1Indiana University School of Medicine, Indianapolis, Indiana
| | - Becky Steck
- 2University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Yongqun He
- 2University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Vivette D’Agati
- 14Columbia University School of Medicine, New York City, New York
| | - Ravi Iyengar
- 11Icahn School of Medicine at Mount Sinai, New York City, New York
| | - Olga G. Troyanskaya
- 12Princeton University, Princeton, New Jersey,14Columbia University School of Medicine, New York City, New York
| | - Laura Barisoni
- 15Duke University School of Medicine, Durham, North Carolina
| | - Joseph Gaut
- 16Washington University in Saint Louis School of Medicine, St. Louis, Missouri
| | - Kun Zhang
- 3Jacobs School of Engineering, University of California, San Diego, California
| | - Zoltan Laszik
- 4University of California San Francisco School of Medicine, San Francisco, California
| | - Brad H. Rovin
- 6Ohio State University College of Medicine, Columbus, Ohio
| | | | - Kumar Sharma
- 7UT-Health San Antonio School of Medicine, San Antonio, Texas
| | - Minnie M. Sarwal
- 4University of California San Francisco School of Medicine, San Francisco, California
| | | | - Charles E. Alpers
- 9Schools of Medicine and Public Health, University of Washington, Seattle, Washington
| | | | - Sanjay Jain
- 16Washington University in Saint Louis School of Medicine, St. Louis, Missouri
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25
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Akilesh S, Nast CC, Yamashita M, Henriksen K, Charu V, Troxell ML, Kambham N, Bracamonte E, Houghton D, Ahmed NI, Chong CC, Thajudeen B, Rehman S, Khoury F, Zuckerman JE, Gitomer J, Raguram PC, Mujeeb S, Schwarze U, Shannon MB, De Castro I, Alpers CE, Najafian B, Nicosia RF, Andeen NK, Smith KD. Multicenter Clinicopathologic Correlation of Kidney Biopsies Performed in COVID-19 Patients Presenting With Acute Kidney Injury or Proteinuria. Am J Kidney Dis 2021; 77:82-93.e1. [PMID: 33045255 PMCID: PMC7546949 DOI: 10.1053/j.ajkd.2020.10.001] [Citation(s) in RCA: 120] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 10/04/2020] [Indexed: 12/14/2022]
Abstract
RATIONALE & OBJECTIVE Kidney biopsy data inform us about pathologic processes associated with infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We conducted a multicenter evaluation of kidney biopsy findings in living patients to identify various kidney disease pathology findings in patients with coronavirus disease 2019 (COVID-19) and their association with SARS-CoV-2 infection. STUDY DESIGN Case series. SETTING & PARTICIPANTS We identified 14 native and 3 transplant kidney biopsies performed for cause in patients with documented recent or concurrent SARS-CoV-2 infection treated at 7 large hospital systems in the United States. OBSERVATIONS Men and women were equally represented in this case series, with a higher proportion of Black (n=8) and Hispanic (n=5) patients. All 17 patients had SARS-CoV-2 infection confirmed by reverse transcriptase-polymerase chain reaction, but only 3 presented with severe COVID-19 symptoms. Acute kidney injury (n=15) and proteinuria (n=11) were the most common indications for biopsy and these symptoms developed concurrently or within 1 week of COVID-19 symptoms in all patients. Acute tubular injury (n=14), collapsing glomerulopathy (n=7), and endothelial injury/thrombotic microangiopathy (n=6) were the most common histologic findings. 2 of the 3 transplant recipients developed active antibody-mediated rejection weeks after COVID-19. 8 patients required dialysis, but others improved with conservative management. LIMITATIONS Small study size and short clinical follow-up. CONCLUSIONS Cases of even symptomatically mild COVID-19 were accompanied by acute kidney injury and/or heavy proteinuria that prompted a diagnostic kidney biopsy. Although acute tubular injury was seen among most of them, uncommon pathology such as collapsing glomerulopathy and acute endothelial injury were detected, and most of these patients progressed to irreversible kidney injury and dialysis.
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Affiliation(s)
- Shreeram Akilesh
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA.
| | - Cynthia C Nast
- Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, CA
| | | | | | - Vivek Charu
- Department of Pathology, Stanford University, Stanford, CA
| | | | | | | | - Donald Houghton
- Department of Pathology, Oregon Health & Science University, Portland, OR
| | | | - Chyi Chyi Chong
- Division of Nephrology, Department of Medicine, University of Arizona, Tucson, AZ
| | - Bijin Thajudeen
- Division of Nephrology, Department of Medicine, University of Arizona, Tucson, AZ
| | - Shehzad Rehman
- Division of Nephrology Department of Medicine, Oregon Health & Science University, Portland, OR
| | - Firas Khoury
- Oregon Kidney & Hypertension Clinic, Portland, OR
| | - Jonathan E Zuckerman
- Department of Pathology and Laboratory Medicine, University of California Los Angeles, Los Angeles, CA
| | | | | | | | - Ulrike Schwarze
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - M Brendan Shannon
- Division of Nephrology, Department of Medicine, University of Washington, Seattle, WA
| | - Iris De Castro
- Division of Nephrology, Department of Medicine, University of Washington, Seattle, WA
| | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Behzad Najafian
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Roberto F Nicosia
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Nicole K Andeen
- Department of Pathology, Oregon Health & Science University, Portland, OR.
| | - Kelly D Smith
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA.
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26
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Soták M, Casselbrant A, Rath E, Zietek T, Strömstedt M, Adingupu DD, Karlsson D, Fritsch Fredin M, Ergang P, Pácha J, Batorsky A, Alpers CE, Börgeson E, Hansen PBL, Ericsson A, Björnson Granqvist A, Wallenius V, Fändriks L, Unwin RJ. Intestinal sodium/glucose cotransporter 3 expression is epithelial and downregulated in obesity. Life Sci 2020; 267:118974. [PMID: 33385407 DOI: 10.1016/j.lfs.2020.118974] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 12/11/2020] [Accepted: 12/20/2020] [Indexed: 12/12/2022]
Abstract
AIM We aimed to determine whether the sodium/glucose cotransporter family member SGLT3, a proposed glucose sensor, is expressed in the intestine and/or kidney, and if its expression is altered in mouse models of obesity and in humans before and after weight-loss surgery. MAIN METHODS We used in-situ hybridization and quantitative PCR to determine whether the Sglt3 isoforms 3a and 3b were expressed in the intestine and kidney of C57, leptin-deficient ob/ob, and diabetic BTBR ob/ob mice. Western blotting and immunohistochemistry were also used to assess SGLT3 protein levels in jejunal biopsies from obese patients before and after weight-loss Roux-en-Y gastric bypass surgery (RYGB), and in lean healthy controls. KEY FINDINGS Sglt3a/3b mRNA was detected in the small intestine (duodenum, jejunum and ileum), but not in the large intestine or kidneys of mice. Both isoforms were detected in epithelial cells (confirmed using intestinal organoids). Expression of Sglt3a/3b mRNA in duodenum and jejunum was significantly lower in ob/ob and BTBR ob/ob mice than in normal-weight littermates. Jejunal SGLT3 protein levels in aged obese patients before RYGB were lower than in lean individuals, but substantially upregulated 6 months post-RYGB. SIGNIFICANCE Our study shows that Sglt3a/3b is expressed primarily in epithelial cells of the small intestine in mice. Furthermore, we observed an association between intestinal mRNA Sglt3a/3b expression and obesity in mice, and between jejunal SGLT3 protein levels and obesity in humans. Further studies are required to determine the possible role of SGLT3 in obesity.
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Affiliation(s)
- Matúš Soták
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden; Department of Molecular and Clinical Medicine, Wallenberg Laboratory, Institute of Medicine, University of Gothenburg, Sweden; Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Sweden.
| | - Anna Casselbrant
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Eva Rath
- Chair of Nutrition and Immunology, Technische Universität München, Freising, Germany
| | - Tamara Zietek
- Department of Nutritional Physiology, Technische Universität München, Freising, Germany
| | - Maria Strömstedt
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Damilola D Adingupu
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Daniel Karlsson
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Maria Fritsch Fredin
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Peter Ergang
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Jiří Pácha
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Anna Batorsky
- Department of Pathology, University of Washington School of Medicine, Seattle, USA
| | - Charles E Alpers
- Department of Pathology, University of Washington School of Medicine, Seattle, USA
| | - Emma Börgeson
- Department of Molecular and Clinical Medicine, Wallenberg Laboratory, Institute of Medicine, University of Gothenburg, Sweden; Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Sweden; Department of Clinical Physiology, Sahlgrenska University Hospital, Sweden
| | - Pernille B L Hansen
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden; Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Sweden
| | - Anette Ericsson
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Anna Björnson Granqvist
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Ville Wallenius
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lars Fändriks
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Robert J Unwin
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden; Department of Renal Medicine, Division of Medicine, University College London, UK
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27
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Sanghavi SF, Roark T, Zelnick LR, Najafian B, Andeen NK, Alpers CE, Pichler R, Ayers E, de Boer IH. Histopathologic and Clinical Features in Patients with Diabetes and Kidney Disease. Kidney360 2020; 1:1217-1225. [PMID: 35372867 PMCID: PMC8815499 DOI: 10.34067/kid.0003962020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/02/2020] [Indexed: 06/14/2023]
Abstract
BACKGROUND The discovery of nondiabetic kidney disease (NDKD) in an individual patient with diabetes may have significant treatment implications. Extensive histopathologic data in this population are lacking, but they may provide insights into the complex pathogenesis of diabetic nephropathy (DN) and reveal specific phenotypes for the development of targeted therapies. This study seeks to elucidate the clinical and laboratory parameters associated with the spectrum of kidney histopathologic features in patients with diabetes. METHODS This study is a retrospective analysis of 399 kidney biopsies assessed from 2014 to 2016 at the University of Washington among patients with diabetes. More comprehensive clinical data were evaluated in a subset of 79 participants. RESULTS Of the 399 biopsies reviewed, 192 (48%) had a primary diagnosis of DN (including 26 with an additional diagnosis), and 207 (52%) had a primary diagnosis of NDKD (including 67 who also had DN). Retinopathy (sensitivity: 0.86; specificity: 0.81; OR, 27.1; 95% CI, 6.8 to 107.7) and higher levels of proteinuria (7.6 versus 4.1 g/d; P=0.004) were associated with DN, whereas a physician description of AKI was associated with a lower risk of DN (OR, 0.13; 95% CI, 0.04 to 0.38). The four most prevalent diagnoses in participants with NDKD were FSGS in 39, nephrosclerosis in 29, IgA nephropathy in 27, and acute tubular injury in 21. CONCLUSIONS Among patients with diabetes who undergo kidney biopsy in the Pacific Northwest, approximately half have DN, and half have NDKD. Retinopathy and more severe proteinuria were associated with DN, and AKI was a more common descriptor in NDKD.Podcast: This article contains a podcast at https://www.asnonline.org/media/podcast/K360/2020_11_25_KID0003962020.mp3.
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Affiliation(s)
- Sarah F. Sanghavi
- Division of Nephrology, Department of Medicine, Veterans Affairs Puget Sound Health Care System, Seattle, Washington
| | - Travis Roark
- Department of Internal Medicine, Scripps Clinic, Scripps Health, San Diego, California
| | - Leila R. Zelnick
- Division of Nephrology, Department of Medicine, Kidney Research Institute, University of Washington, Seattle, Washington
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, Washington
| | - Nicole K. Andeen
- Department of Pathology, Oregon Health & Science University, Portland, Oregon
| | - Charles E. Alpers
- Department of Pathology, University of Washington, Seattle, Washington
| | - Raimund Pichler
- Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington
| | - Ernest Ayers
- Division of Nephrology, Department of Medicine, Kidney Research Institute, University of Washington, Seattle, Washington
| | - Ian H. de Boer
- Division of Nephrology, Department of Medicine, Veterans Affairs Puget Sound Health Care System, Seattle, Washington
- Division of Nephrology, Department of Medicine, Kidney Research Institute, University of Washington, Seattle, Washington
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28
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Akilesh S, Nicosia RF, Alpers CE, Tretiakova M, Hsiang TY, Gale M, Smith KD. Characterizing Viral Infection by Electron Microscopy: Lessons from the Coronavirus Disease 2019 Pandemic. Am J Pathol 2020; 191:222-227. [PMID: 33227297 PMCID: PMC7678435 DOI: 10.1016/j.ajpath.2020.11.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 10/20/2020] [Accepted: 11/03/2020] [Indexed: 12/13/2022]
Abstract
The severe acute respiratory syndrome coronavirus 2 pandemic has infected millions of individuals in the United States and caused hundreds of thousands of deaths. Direct infection of extrapulmonary tissues has been postulated, and using sensitive techniques, viral RNA has been detected in multiple organs in the body, including the kidney. However, direct infection of tissues outside of the lung has been more challenging to demonstrate. This has been in part due to misinterpretation of electron microscopy studies. In this perspective, we will discuss what is known about coronavirus infection, some of the basic ultrastructural cell biology that has been confused for coronavirus infection of cells, and rigorous criteria that should be used when identifying pathogens by electron microscopy.
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Affiliation(s)
- Shreeram Akilesh
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Roberto F Nicosia
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Charles E Alpers
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Maria Tretiakova
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Tien-Ying Hsiang
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, Washington
| | - Michael Gale
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, Washington
| | - Kelly D Smith
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington.
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29
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Henriksen J, Kolognizak T, Houghton T, Cherne S, Zhen D, Cimino PJ, Latimer CS, Scherpelz KP, Yoda RA, Alpers CE, Chhieng DF, Keene CD, Gonzalez-Cuyar LF. Rapid Validation of Telepathology by an Academic Neuropathology Practice During the COVID-19 Pandemic. Arch Pathol Lab Med 2020; 144:1311-1320. [PMID: 32551815 PMCID: PMC10777891 DOI: 10.5858/arpa.2020-0372-sa] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2020] [Indexed: 11/06/2022]
Abstract
CONTEXT.— The coronavirus disease 19 (COVID-19) pandemic is placing unparalleled burdens on regional and institutional resources in medical facilities across the globe. This disruption is causing unprecedented downstream effects to traditionally established channels of patient care delivery, including those of essential anatomic pathology services. With Washington state being the initial North American COVID-19 epicenter, the University of Washington in Seattle has been at the forefront of conceptualizing and implementing innovative solutions in order to provide uninterrupted quality patient care amidst this growing crisis. OBJECTIVE.— To conduct a rapid validation study assessing our ability to reliably provide diagnostic neuropathology services via a whole slide imaging (WSI) platform as part of our departmental COVID-19 planning response. DESIGN.— This retrospective study assessed diagnostic concordance of neuropathologic diagnoses rendered via WSI as compared to those originally established via traditional histopathology in a cohort of 30 cases encompassing a broad range of neurosurgical and neuromuscular entities. This study included the digitalization of 93 slide preparations, which were independently examined by groups of board-certified neuropathologists and neuropathology fellows. RESULTS.— There were no major or minor diagnostic discrepancies identified in either the attending neuropathologist or neuropathology trainee groups for either the neurosurgical or neuromuscular case cohorts. CONCLUSIONS.— Our study demonstrates that accuracy of neuropathologic diagnoses and interpretation of ancillary preparations via WSI are not inferior to those generated via traditional microscopy. This study provides a framework for rapid subspecialty validation and deployment of WSI for diagnostic purposes during a pandemic event.
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Affiliation(s)
| | | | - Tracy Houghton
- From the Department of Pathology, University of Washington, Seattle
| | - Steve Cherne
- From the Department of Pathology, University of Washington, Seattle
| | - Daisy Zhen
- From the Department of Pathology, University of Washington, Seattle
| | - Patrick J Cimino
- From the Department of Pathology, University of Washington, Seattle
| | | | | | - Rebecca A Yoda
- From the Department of Pathology, University of Washington, Seattle
| | - Charles E Alpers
- From the Department of Pathology, University of Washington, Seattle
| | - David F Chhieng
- From the Department of Pathology, University of Washington, Seattle
| | - C Dirk Keene
- From the Department of Pathology, University of Washington, Seattle
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30
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Skopelja-Gardner S, Colonna L, Hermanson P, Sun X, Tanaka L, Tai J, Nguyen Y, Snyder JM, Alpers CE, Hudkins KL, Salant DJ, Peng Y, Elkon KB. Complement Deficiencies Result in Surrogate Pathways of Complement Activation in Novel Polygenic Lupus-like Models of Kidney Injury. J Immunol 2020; 204:2627-2640. [PMID: 32238460 PMCID: PMC7365257 DOI: 10.4049/jimmunol.1901473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/15/2020] [Indexed: 12/27/2022]
Abstract
Lupus nephritis (LN) is a major contributor to morbidity and mortality in lupus patients, but the mechanisms of kidney damage remain unclear. In this study, we introduce, to our knowledge, novel models of LN designed to resemble the polygenic nature of human lupus by embodying three key genetic alterations: the Sle1 interval leading to anti-chromatin autoantibodies; Mfge8-/- , leading to defective clearance of apoptotic cells; and either C1q-/- or C3-/- , leading to low complement levels. We report that proliferative glomerulonephritis arose only in the presence of all three abnormalities (i.e., in Sle1.Mfge8 -/- C1q -/- and Sle1.Mfge8 -/- C3 -/- triple-mutant [TM] strains [C1q -/-TM and C3-/- TM, respectively]), with structural kidney changes resembling those in LN patients. Unexpectedly, both TM strains had significant increases in autoantibody titers, Ag spread, and IgG deposition in the kidneys. Despite the early complement component deficiencies, we observed assembly of the pathogenic terminal complement membrane attack complex in both TM strains. In C1q-/- TM mice, colocalization of MASP-2 and C3 in both the glomeruli and tubules indicated that the lectin pathway likely contributed to complement activation and tissue injury in this strain. Interestingly, enhanced thrombin activation in C3-/- TM mice and reduction of kidney injury following attenuation of thrombin generation by argatroban in a serum-transfer nephrotoxic model identified thrombin as a surrogate pathway for complement activation in C3-deficient mice. These novel mouse models of human lupus inform the requirements for nephritis and provide targets for intervention.
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Affiliation(s)
| | - Lucrezia Colonna
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Payton Hermanson
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Xizhang Sun
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Lena Tanaka
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Joyce Tai
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Yenly Nguyen
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Jessica M Snyder
- Department of Comparative Medicine, University of Washington, Seattle, WA 98109
| | - Charles E Alpers
- Department of Nephrology, University of Washington, Seattle, WA 98109
| | - Kelly L Hudkins
- Department of Nephrology, University of Washington, Seattle, WA 98109
| | - David J Salant
- Division of Nephrology, Boston University, Boston, MA 02215; and
| | - YuFeng Peng
- Division of Rheumatology, University of Washington, Seattle, WA 98109;
| | - Keith B Elkon
- Division of Rheumatology, University of Washington, Seattle, WA 98109;
- Department of Immunology, University of Washington, Seattle, WA 98109
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31
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Hudkins KL, Wietecha TA, Steegh F, Alpers CE. Beneficial effect on podocyte number in experimental diabetic nephropathy resulting from combined atrasentan and RAAS inhibition therapy. Am J Physiol Renal Physiol 2020; 318:F1295-F1305. [PMID: 32249614 DOI: 10.1152/ajprenal.00498.2019] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Podocyte loss and proteinuria are both key features of human diabetic nephropathy (DN). The leptin-deficient BTBR mouse strain with the ob/ob mutation develops progressive weight gain, type 2 diabetes, and diabetic nephropathy that has many features of advanced human DN, including increased mesangial matrix, mesangiolysis, podocyte loss, and proteinuria. Selective antagonism of the endothelin-1 type A receptor (ETAR) by atrasentan treatment in combination with renin-angiotensin-aldosterone system inhibition with losartan has been shown to have the therapeutic benefit of lowering proteinuria in patients with DN, but the underlying mechanism for this benefit is not well understood. Using a similar therapeutic approach in diabetic BTBR ob/ob mice, this treatment regimen significantly increased glomerular podocyte number compared with diabetic BTBR ob/ob controls and suggested that parietal epithelial cells were a source for podocyte restoration. Atrasentan treatment alone also increased podocyte number but to a lesser degree. Mice treated with atrasentan demonstrated a reduction in proteinuria, matching the functional improvement reported in humans. This is a first demonstration that treatment with the highly selective ETAR antagonist atrasentan can lead to restoration of the diminished podocyte number characteristic of DN in humans and thereby underlies the reduction in proteinuria in patients with diabetes undergoing similar treatment. The benefit of ETAR antagonism in DN extended to a decrease in mesangial matrix as measured by a reduction in accumulations of collagen type IV in both the atrasentan and atrasentan + losartan-treated groups compared with untreated controls.
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Affiliation(s)
- Kelly L Hudkins
- Department of Pathology, University of Washington, Seattle, Washington
| | - Tomasz A Wietecha
- Department of Pathology, University of Washington, Seattle, Washington
| | - Floor Steegh
- Department of Pathology, University of Washington, Seattle, Washington
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, Washington
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Björnson Granqvist A, Ericsson A, Sanchez J, Tonelius P, William-Olsson L, Dahlqvist U, Andersson AK, Tesan Tomic T, Hudkins K, Alpers CE, Pellegrini G, Söderberg M. High-protein diet accelerates diabetes and kidney disease in the BTBR ob/ob mouse. Am J Physiol Renal Physiol 2020; 318:F763-F771. [PMID: 31961715 DOI: 10.1152/ajprenal.00484.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
There is a need for improved animal models that better translate to human kidney disease to predict outcome of pharmacological effects in the patient. The diabetic BTBRob/ob mouse model mimics key features of early diabetic nephropathy in humans, but with chronic injury limited to glomeruli. To explore if we could induce an accelerated and more advanced disease phenotype that closer translates to human disease, we challenged BTBRob/ob mice with a high-protein diet (HPD; 30%) and followed the progression of metabolic and renal changes up to 20 wk of age. Animals on the HPD showed enhanced metabolic derangements, evidenced by further increased levels of glucose, HbA1C, cholesterol, and alanine aminotransferase. The urinary albumin-to-creatinine ratio was markedly increased with a 53-fold change compared with lean controls, whereas BTBRob/ob mice on the standard diet only presented an 8-fold change. HPD resulted in more advanced mesangial expansion already at 14 wk of age compared with BTBRob/ob mice on the standard diet and also aggravated glomerular pathology as well as interstitial fibrosis. Gene expression analysis revealed that HPD triggered expression of markers of fibrosis and inflammation in the kidney and increased oxidative stress markers in urine. This study showed that HPD significantly aggravated renal injury in BTBRob/ob mice by further advancing albuminuria, glomerular, and tubulointerstitial pathology by 20 wk of age. This mouse model offers closer translation to humans and enables exploration of new end points for pharmacological efficacy studies that also holds promise to shorten study length.
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Affiliation(s)
- Anna Björnson Granqvist
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Anette Ericsson
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - José Sanchez
- Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Pernilla Tonelius
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Lena William-Olsson
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Ulrika Dahlqvist
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Ann-Katrin Andersson
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Tajana Tesan Tomic
- Bioscience, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Kelly Hudkins
- Department of Pathology, University of Washington, Seattle, Washington
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, Washington
| | - Giovanni Pellegrini
- Pathology, Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Magnus Söderberg
- Pathology, Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
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Rovin BH, Caster DJ, Cattran DC, Gibson KL, Hogan JJ, Moeller MJ, Roccatello D, Cheung M, Wheeler DC, Winkelmayer WC, Floege J, Alpers CE, Ayoub I, Bagga A, Barbour SJ, Barratt J, Chan DT, Chang A, Choo JCJ, Cook HT, Coppo R, Fervenza FC, Fogo AB, Fox JG, Glassock RJ, Harris D, Hodson EM, Hogan JJ, Hoxha E, Iseki K, Jennette JC, Jha V, Johnson DW, Kaname S, Katafuchi R, Kitching AR, Lafayette RA, Li PK, Liew A, Lv J, Malvar A, Maruyama S, Mejía-Vilet JM, Mok CC, Nachman PH, Nester CM, Noiri E, O'Shaughnessy MM, Özen S, Parikh SM, Park HC, Peh CA, Pendergraft WF, Pickering MC, Pillebout E, Radhakrishnan J, Rathi M, Ronco P, Smoyer WE, Tang SC, Tesař V, Thurman JM, Trimarchi H, Vivarelli M, Walters GD, Wang AYM, Wenderfer SE, Wetzels JF. Management and treatment of glomerular diseases (part 2): conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference. Kidney Int 2020; 95:281-295. [PMID: 30665569 DOI: 10.1016/j.kint.2018.11.008] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 10/30/2018] [Accepted: 11/01/2018] [Indexed: 02/06/2023]
Abstract
In November 2017, the Kidney Disease: Improving Global Outcomes (KDIGO) initiative brought a diverse panel of experts in glomerular diseases together to discuss the 2012 KDIGO glomerulonephritis guideline in the context of new developments and insights that had occurred over the years since its publication. During this KDIGO Controversies Conference on Glomerular Diseases, the group examined data on disease pathogenesis, biomarkers, and treatments to identify areas of consensus and areas of controversy. This report summarizes the discussions on primary podocytopathies, lupus nephritis, anti-neutrophil cytoplasmic antibody-associated nephritis, complement-mediated kidney diseases, and monoclonal gammopathies of renal significance.
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Affiliation(s)
- Brad H Rovin
- Division of Nephrology, The Ohio State University, Wexner Medical Center, Columbus, Ohio, USA.
| | - Dawn J Caster
- Department of Medicine, University of Louisville School of Medicine, Louisville, Kentucky, USA
| | - Daniel C Cattran
- Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Keisha L Gibson
- University of North Carolina Kidney Center at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jonathan J Hogan
- Division of Nephrology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Marcus J Moeller
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule, University of Aachen, Aachen, Germany
| | - Dario Roccatello
- CMID (Center of Research of Immunopathology and Rare Diseases), and Division of Nephrology and Dialysis (ERK-Net member), University of Turin, Italy
| | | | | | - Wolfgang C Winkelmayer
- Selzman Institute for Kidney Health, Section of Nephrology, Department of Medicine, Baylor College of Medicine, Houston, Texas, USA
| | - Jürgen Floege
- Division of Nephrology, Rheinisch-Westfälische Technische Hochschule, University of Aachen, Aachen, Germany.
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Andeen NK, Troxell ML, Riazy M, Avasare RS, Lapasia J, Jefferson JA, Akilesh S, Najafian B, Nicosia RF, Alpers CE, Smith KD. Fibrillary Glomerulonephritis: Clinicopathologic Features and Atypical Cases from a Multi-Institutional Cohort. Clin J Am Soc Nephrol 2019; 14:1741-1750. [PMID: 31685544 PMCID: PMC6895488 DOI: 10.2215/cjn.03870319] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 08/02/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND OBJECTIVES Fibrillary GN has been defined as an immune complex-mediated GN with amyloid-like fibrils larger than amyloid which are IgG positive and Congo red negative. With discovery of DNAJB9 as a highly sensitive and specific marker for fibrillary GN, the specificity of the morphologic criteria for establishing the diagnosis of fibrillary GN has come into question. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We sought to (1) determine anatomic characteristics that best define fibrillary GN and (2) identify clinical and pathologic features that predict outcomes. RESULTS We retrospectively reviewed kidney biopsies from patients diagnosed with fibrillary GN or suspected fibrillary GN between 1997 and 2017 (n=266, 65% female, median age 61). Approximately 11% of kidney biopsies had one or more unusual feature including monotypic deposits, Congo red positivity, or unusual fibril diameter. Fibrillary GN as a possible monoclonal gammopathy of renal significance represented <1% of cases. Immunostaining for DNAJB9 confirmed fibrillary GN in 100% of cases diagnosed as fibrillary GN and 79% of atypical cases diagnosed as possible fibrillary GN. At a median time of 24 months (interquartile range, 8-46 months) after biopsy (n=100), 53% of patients reached the combined primary outcome of ESKD or death, 18% had CKD, and 18% had partial remission. On multivariable analysis, male sex (adjusted hazard ratio [aHR], 3.82; 95% confidence interval [95% CI], 1.97 to 7.37) and eGFR were the most significant predictors of primary outcome (aHR of 8.02 if eGFR <30 ml/min per 1.73 m2 [95% CI, 1.85 to 34.75]; aHR of 6.44 if eGFR 30 to <45 ml/min per 1.73 m2 [95% CI, 1.38 to 29.99]). Immunosuppressive therapy with rituximab was significantly associated with stabilization of disease progression. CONCLUSIONS Detection of DNAJB9 is a useful diagnostic tool for diagnosing atypical forms of fibrillary GN. The outcomes for fibrillary GN are poor and progression to ESKD is influenced predominantly by the degree of kidney insufficiency at the time of diagnosis and male sex. Rituximab may help preserve kidney function for select patients with fibrillary GN. PODCAST This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2019_11_04_CJN03870319.mp3.
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Affiliation(s)
- Nicole K. Andeen
- Department of Pathology, St. Paul Hospital, University of British Columbia, Vancouver, Canada
| | - Megan L. Troxell
- Division of Nephrology, Department of Medicine, Oregon Health & Science University, Portland Oregon
| | - Maziar Riazy
- Nephrology Service Line, The Permanente Medical Group, Kaiser Permanente Northern California, Oakland, California
| | | | - Jessica Lapasia
- Nephrology Service Line, The Permanente Medical Group, Kaiser Permanente Northern California, Oakland, California
| | | | | | | | - Roberto F. Nicosia
- Department of Pathology, University of Washington; and
- Seattle Veterans Affairs Medical Center, Seattle, Washington
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Chan GC, Eng DG, Miner JH, Alpers CE, Hudkins K, Chang A, Pippin JW, Shankland SJ. Differential expression of parietal epithelial cell and podocyte extracellular matrix proteins in focal segmental glomerulosclerosis and diabetic nephropathy. Am J Physiol Renal Physiol 2019; 317:F1680-F1694. [PMID: 31630546 PMCID: PMC6962515 DOI: 10.1152/ajprenal.00266.2019] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 10/08/2019] [Accepted: 10/10/2019] [Indexed: 01/03/2023] Open
Abstract
In healthy glomeruli, parietal epithelial cell (PEC)-derived extracellular matrix (ECM) proteins include laminin-β1, perlecan, and collagen type IV-α2 and podocyte-specific ECM proteins include laminin-β2, agrin, and collagen type IV-α4. This study aimed to define individual ECM protein isoform expression by PECs in both experimental and human focal segmental glomerulosclerosis (FSGS) and diabetic nephropathy (DN) and to determine if changes were CD44 dependent. In experimental FSGS induced with a cytotoxic podocyte antibody and in the BTBR ob/ob mouse model of DN, PEC-derived protein staining was significantly increased in PECs. Dual staining also showed de novo expression of the podocyte-specific ECM proteins laminin-β2 and agrin in PECs. Similar findings were observed in biopsies from patients with FSGS and DN. Increases in individual ECM proteins colocalized with CD44 in PECs in disease. To determine the role of CD44, FSGS was induced in CD44-/- and CD44+/+ mice. PEC staining for perlecan, collagen type IV-α2, laminin-β2, and agrin were significantly lower in diseased CD44-/- mice compared with diseased CD44+/+ mice. These results show that in experimental and human FSGS and DN, PECs typically in an activated state, produce both PEC-derived and podocyte-specific ECM protein isoforms, and that the majority of these changes were dependent on CD44.
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Affiliation(s)
- Gek Cher Chan
- Division of Nephrology, University of Washington, Seattle, Washington
- Division of Nephrology, National University Hospital, Singapore
| | - Diana G Eng
- Division of Nephrology, University of Washington, Seattle, Washington
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, Washington
| | - Kelly Hudkins
- Department of Pathology, University of Washington, Seattle, Washington
| | - Anthony Chang
- Department of Pathology, University of Chicago, Chicago, Illinois
| | - Jeffrey W Pippin
- Division of Nephrology, University of Washington, Seattle, Washington
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Alvarado AS, Andeen NK, Brodsky S, Hinton A, Nadasdy T, Alpers CE, Blosser C, Najafian B, Rovin BH. Location of glomerular immune deposits, not codeposition of immunoglobulin G, influences definitive renal outcomes in immunoglobulin A nephropathy. Nephrol Dial Transplant 2019; 33:1168-1175. [PMID: 28992348 DOI: 10.1093/ndt/gfx238] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 06/13/2017] [Indexed: 12/25/2022] Open
Abstract
Background It has been suggested that the prognosis of immunoglobulin (IgA) nephropathy (IgAN) is adversely affected if there is codeposition of IgG in the glomeruli or if immune deposits are present in the glomerular capillary walls. We sought to understand how these variables affect clinical outcome. Methods A total of 80 IgAN biopsies were retrospectively divided into groups: (i) IgA without IgG deposition versus IgA + IgG and (ii) immune deposits restricted to the mesangium versus mesangium and peripheral capillary walls (PCWs). The association of these groups with the composite primary outcome of renal replacement therapy, renal transplant, death or doubling of serum creatinine (SCr) concentration was determined. The change in estimated glomerular filtration rate (eGFR) was also assessed. Covariates examined were age, sex, race, SCr and proteinuria level at biopsy and at follow-up, duration of follow-up, treatment, Oxford score and presence of crescents. Results IgG codeposition showed a trend toward endocapillary hypercellularity (P = 0.082); there were no other baseline differences between the IgA (n = 55) and IgA + IgG (n = 25) groups. At a median follow-up time of 29 months, the combined primary outcome was reached in 24 patients, 16 with IgA and 8 with IgA + IgG (P = 0.82). Patients with immune deposits in the PCWs (n = 21) presented with higher baseline proteinuria than those with deposits limited to the mesangium (n = 59; P = 0.025), were more likely to have crescents/segmental glomerular necrosis on biopsy (P = 0.047) and were more likely to reach the combined primary outcome (P = 0.026). Biopsies with crescents/segmental glomerular necrosis were associated with endocapillary hypercellularity (P < 0.001). Conclusions In this multicenter IgAN cohort, IgG co-deposition and the location of glomerular immune deposits in the PCWs were both associated with greater histologic activity on renal biopsy, but only the location of glomerular immune deposits in the PCWs was associated with a significantly increased risk for end-stage renal disease, transplant, death and/or doubling of SCr.
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Affiliation(s)
- Anthony S Alvarado
- Department of Medicine, Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Nicole K Andeen
- Department of Pathology, University of Washington Medical Center, Seattle WA, USA
| | - Sergey Brodsky
- Department of Pathology, Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Alice Hinton
- Division of Biostatistics, College of Public Health, Ohio State University, Columbus, OH, USA
| | - Tibor Nadasdy
- Department of Pathology, Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Charles E Alpers
- Department of Pathology, University of Washington Medical Center, Seattle WA, USA
| | - Christopher Blosser
- Department of Medicine, Nephrology Division, University of Washington Medical Center, Seattle, WA, USA
| | - Behzad Najafian
- Department of Pathology, University of Washington Medical Center, Seattle WA, USA
| | - Brad H Rovin
- Department of Medicine, Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, OH, USA
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Nespoux J, Patel R, Hudkins KL, Huang W, Freeman B, Kim YC, Koepsell H, Alpers CE, Vallon V. Gene deletion of the Na +-glucose cotransporter SGLT1 ameliorates kidney recovery in a murine model of acute kidney injury induced by ischemia-reperfusion. Am J Physiol Renal Physiol 2019; 316:F1201-F1210. [PMID: 30995111 PMCID: PMC6620597 DOI: 10.1152/ajprenal.00111.2019] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 04/05/2019] [Accepted: 04/10/2019] [Indexed: 12/12/2022] Open
Abstract
Renal Na+-glucose cotransporter SGLT1 mediates glucose reabsorption in the late proximal tubule, a hypoxia-sensitive tubular segment that enters the outer medulla. Gene deletion in mice (Sglt1-/-) was used to determine the role of the cotransporter in acute kidney injury induced by ischemia-reperfusion (IR), including the initial injury and subsequent recovery phase. On days 1 and 16 after IR, absolute and fractional urinary glucose excretion remained greater in Sglt1-/- mice versus wild-type (WT) littermates, consistent with a sustained contribution of SGLT1 to tubular glucose reabsorption in WT mice. Absence of SGLT1 did not affect the initial kidney impairment versus WT mice, as indicated by similar increases on day 1 in plasma concentrations of creatinine and urinary excretion of the tubular injury marker kidney injury molecule-1 as well as a similar rise in plasma osmolality and fall in urine osmolality as indicators of impaired urine concentration. Recovery of kidney function on days 14/16, however, was improved in Sglt1-/- versus WT mice, as indicated by lower plasma creatinine, higher glomerula filtration rate (by FITC-sinistrin in awake mice), and more completely restored urine and plasma osmolality. This was associated with a reduced tubular injury score in the cortex and outer medulla, better preserved renal mRNA expression of tubular transporters (Sglt2 and Na+-K+-2Cl- cotransporter Nkcc2), and a lesser rise in renal mRNA expression of markers of injury, inflammation, and fibrosis [kidney injury molecule-1, chemokine (C-C motif) ligand 2, fibronectin 1, and collagen type I-α1] in Sglt1-/- versus WT mice. These results suggest that SGLT1 activity in the late proximal tubule may have deleterious effects during recovery of IR-induced acute kidney injury and identify SGLT1 as a potential therapeutic target.
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Affiliation(s)
- Josselin Nespoux
- Department of Medicine, University of California , San Diego, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Rohit Patel
- Department of Medicine, University of California , San Diego, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Kelly L Hudkins
- Department of Pathology, University of Washington , Seattle, Washington
| | - Winnie Huang
- Department of Medicine, University of California , San Diego, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Brent Freeman
- Department of Medicine, University of California , San Diego, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Young Chul Kim
- Department of Medicine, University of California , San Diego, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Hermann Koepsell
- Department of Molecular Plant Physiology, University Würzburg , Würzburg , Germany
| | - Charles E Alpers
- Department of Pathology, University of Washington , Seattle, Washington
| | - Volker Vallon
- Department of Medicine, University of California , San Diego, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
- Department of Pharmacology, University of California , San Diego, California
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38
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Lusco MA, Chen YP, Cheng H, Dong HR, Najafian B, Alpers CE, Fogo AB. AJKD Atlas of Renal Pathology: Fibronectin Glomerulopathy. Am J Kidney Dis 2019; 70:e21-e22. [PMID: 29055354 DOI: 10.1053/j.ajkd.2017.09.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 09/06/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Mark A Lusco
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Yi-Pu Chen
- Division of Nephrology, Affiliated Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Hong Cheng
- Division of Nephrology, Affiliated Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Hong-Rui Dong
- Division of Nephrology, Affiliated Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, WA
| | | | - Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN.
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Kubiak RW, Zelnick LR, Hoofnagle AN, Alpers CE, Terry CM, Shiu YT, Cheung AK, de Boer IH, Robinson-Cohen C, Allon M, Dember LM, Feldman HI, Himmelfarb J, Huber TS, Roy-Chaudhury P, Vazquez MA, Kusek JW, Beck GJ, Imrey PB, Kestenbaum B. Mineral Metabolism Disturbances and Arteriovenous Fistula Maturation. Eur J Vasc Endovasc Surg 2019; 57:719-728. [PMID: 31000459 PMCID: PMC7259372 DOI: 10.1016/j.ejvs.2019.01.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 01/22/2019] [Indexed: 02/08/2023]
Abstract
BACKGROUND The arteriovenous fistula (AVF) is central to haemodialysis treatment, but up to half of surgically created AVF fail to mature. Chronic kidney disease often leads to mineral metabolism disturbances that may interfere with AVF maturation through adverse vascular effects. This study tested associations between mineral metabolism markers and vein histology at AVF creation and unassisted and overall clinical AVF maturation. METHODS Concentrations of fibroblast growth factor 23, parathyroid hormone, calcium, phosphate, and vitamin D metabolites: 1,25(OH)2D, 24,25(OH)2D, 25(OH)D, and bioavailable 25(OH)D were measured in pre-operative serum samples from 562 of 602 participants in the Haemodialysis Fistula Maturation Study, a multicentre, prospective cohort study of patients undergoing surgical creation of an autologous upper extremity AVF. Unassisted and overall AVF maturation were ascertained for 540 and 527 participants, respectively, within nine months of surgery or four weeks of dialysis initiation. Study personnel obtained vein segments adjacent to the portion of the vein used for anastomosis, which were processed, embedded, and stained for measurement of neointimal hyperplasia, calcification, and collagen deposition in the medial wall. RESULTS Participants in this substudy were 71% male, 43% black, and had a mean age of 55 years. Failure to achieve AVF maturation without assistance occurred in 288 (53%) participants for whom this outcome was determined. In demographic and further adjusted models, mineral metabolism markers were not significantly associated with vein histology characteristics, unassisted AVF maturation failure, or overall maturation failure, other than a biologically unexplained association of higher 24,25(OH)2D with overall failure. This exception aside, associations were non-significant for continuous and categorical analyses and relevant subgroups. CONCLUSIONS Serum concentrations of measured mineral metabolites were not substantially associated with major histological characteristics of veins in patients undergoing AVF creation surgery, or with AVF maturation failure, suggesting that efforts to improve AVF maturation rates should increase attention to other processes such as vein mechanics, anatomy, and cellular metabolism among end stage renal disease patients.
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Affiliation(s)
- Rachel W Kubiak
- Kidney Research Institute, University of Washington, Seattle, WA, USA; Department of Epidemiology, University of Washington, Seattle, WA, USA.
| | - Leila R Zelnick
- Kidney Research Institute, University of Washington, Seattle, WA, USA
| | - Andy N Hoofnagle
- Department of Laboratory Medicine, University of Washington, Seattle, WA, USA
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, WA, USA
| | - Christi M Terry
- Division of Nephrology & Hypertension, University of Utah and Veterans Affairs Salt Lake City Healthcare System, Salt Lake City, UT, USA
| | - Yan-Ting Shiu
- Division of Nephrology & Hypertension, University of Utah and Veterans Affairs Salt Lake City Healthcare System, Salt Lake City, UT, USA
| | - Alfred K Cheung
- Division of Nephrology & Hypertension, University of Utah and Veterans Affairs Salt Lake City Healthcare System, Salt Lake City, UT, USA
| | - Ian H de Boer
- Kidney Research Institute, University of Washington, Seattle, WA, USA
| | | | - Michael Allon
- Department of Vascular Surgery, University of Alabama, Birmingham, AL, USA
| | - Laura M Dember
- Renal, Electrolyte & Hypertension Division, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Harold I Feldman
- Department of Biostatistics and Epidemiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | | | - Thomas S Huber
- Division of Vascular Surgery and Endovascular Therapy, University of Florida College of Medicine, Gainesville, FL, USA
| | - Prabir Roy-Chaudhury
- Division of Nephrology and the University of Arizona Kidney Disease Program, University of Arizona, Tucson, AZ, USA
| | - Miguel A Vazquez
- Division of Nephrology, University of Texas Southwestern, Dallas, TX, USA
| | - John W Kusek
- National Institutes of Diabetes and Digestive and Kidney Diseases, Division of Kidney, Urologic & Hematologic Diseases, Bethesda, MD, USA
| | - Gerald J Beck
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA
| | - Peter B Imrey
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA; Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, USA
| | - Bryan Kestenbaum
- Kidney Research Institute, University of Washington, Seattle, WA, USA
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Sieber KB, Batorsky A, Siebenthall K, Hudkins KL, Vierstra JD, Sullivan S, Sur A, McNulty M, Sandstrom R, Reynolds A, Bates D, Diegel M, Dunn D, Nelson J, Buckley M, Kaul R, Sampson MG, Himmelfarb J, Alpers CE, Waterworth D, Akilesh S. Integrated Functional Genomic Analysis Enables Annotation of Kidney Genome-Wide Association Study Loci. J Am Soc Nephrol 2019; 30:421-441. [PMID: 30760496 PMCID: PMC6405142 DOI: 10.1681/asn.2018030309] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 12/26/2018] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Linking genetic risk loci identified by genome-wide association studies (GWAS) to their causal genes remains a major challenge. Disease-associated genetic variants are concentrated in regions containing regulatory DNA elements, such as promoters and enhancers. Although researchers have previously published DNA maps of these regulatory regions for kidney tubule cells and glomerular endothelial cells, maps for podocytes and mesangial cells have not been available. METHODS We generated regulatory DNA maps (DNase-seq) and paired gene expression profiles (RNA-seq) from primary outgrowth cultures of human glomeruli that were composed mainly of podocytes and mesangial cells. We generated similar datasets from renal cortex cultures, to compare with those of the glomerular cultures. Because regulatory DNA elements can act on target genes across large genomic distances, we also generated a chromatin conformation map from freshly isolated human glomeruli. RESULTS We identified thousands of unique regulatory DNA elements, many located close to transcription factor genes, which the glomerular and cortex samples expressed at different levels. We found that genetic variants associated with kidney diseases (GWAS) and kidney expression quantitative trait loci were enriched in regulatory DNA regions. By combining GWAS, epigenomic, and chromatin conformation data, we functionally annotated 46 kidney disease genes. CONCLUSIONS We demonstrate a powerful approach to functionally connect kidney disease-/trait-associated loci to their target genes by leveraging unique regulatory DNA maps and integrated epigenomic and genetic analysis. This process can be applied to other kidney cell types and will enhance our understanding of genome regulation and its effects on gene expression in kidney disease.
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Affiliation(s)
| | - Anna Batorsky
- Altius Institute for Biomedical Sciences, Seattle, Washington
| | | | | | - Jeff D Vierstra
- Altius Institute for Biomedical Sciences, Seattle, Washington
| | | | - Aakash Sur
- Phase Genomics Inc., Seattle, Washington
- Department of Biomedical and Health Informatics, and
| | - Michelle McNulty
- Division of Pediatric Nephrology, Department of Pediatrics, University of Michigan School of Medicine, Ann Arbor, Michigan; and
| | | | - Alex Reynolds
- Altius Institute for Biomedical Sciences, Seattle, Washington
| | - Daniel Bates
- Altius Institute for Biomedical Sciences, Seattle, Washington
| | - Morgan Diegel
- Altius Institute for Biomedical Sciences, Seattle, Washington
| | - Douglass Dunn
- Altius Institute for Biomedical Sciences, Seattle, Washington
| | - Jemma Nelson
- Altius Institute for Biomedical Sciences, Seattle, Washington
| | - Michael Buckley
- Altius Institute for Biomedical Sciences, Seattle, Washington
| | - Rajinder Kaul
- Altius Institute for Biomedical Sciences, Seattle, Washington
| | - Matthew G Sampson
- Division of Pediatric Nephrology, Department of Pediatrics, University of Michigan School of Medicine, Ann Arbor, Michigan; and
| | - Jonathan Himmelfarb
- Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington
- Kidney Research Institute, Seattle, Washington
| | - Charles E Alpers
- Department of Anatomic Pathology
- Kidney Research Institute, Seattle, Washington
| | | | - Shreeram Akilesh
- Department of Anatomic Pathology,
- Kidney Research Institute, Seattle, Washington
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41
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Affiliation(s)
- Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN.
| | - Mark A Lusco
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, WA
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Najafian B, Fogo AB, Lusco MA, Alpers CE. AJKD Atlas of Renal Pathology: IgG4-Related Tubulointerstitial Nephritis. Am J Kidney Dis 2018; 69:e19-e20. [PMID: 28340854 DOI: 10.1053/j.ajkd.2017.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 02/08/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Behzad Najafian
- Department of Pathology, University of Washington, Seattle, WA
| | - Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN.
| | - Mark A Lusco
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
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43
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Fogo AB, Lusco MA, Najafian B, Alpers CE. AJKD Atlas of Renal Pathology: Type III Collagen Glomerulopathy. Am J Kidney Dis 2018; 69:e25-e26. [PMID: 28532638 DOI: 10.1053/j.ajkd.2017.04.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 04/06/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN.
| | - Mark A Lusco
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, WA
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44
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Fogo AB, Lusco MA, Najafian B, Alpers CE. AJKD Atlas of Renal Pathology: Osmotic Tubular Injury. Am J Kidney Dis 2018; 69:e11-e12. [PMID: 28115065 DOI: 10.1053/j.ajkd.2016.12.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 12/05/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN.
| | - Mark A Lusco
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, WA
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45
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Fogo AB, Lusco MA, Najafian B, Alpers CE. AJKD Atlas of Renal Pathology: Kidney Disease in Primary Sjögren Syndrome. Am J Kidney Dis 2018; 69:e29-e30. [PMID: 28532640 DOI: 10.1053/j.ajkd.2017.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 04/06/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN.
| | - Mark A Lusco
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, WA
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46
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Lusco MA, Fogo AB, Najafian B, Alpers CE. AJKD Atlas of Renal Pathology: Calcineurin Inhibitor Nephrotoxicity. Am J Kidney Dis 2018; 69:e21-e22. [PMID: 28434526 DOI: 10.1053/j.ajkd.2017.02.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 02/08/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Mark A Lusco
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN.
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, WA
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47
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Chozinski TJ, Mao C, Halpern AR, Pippin JW, Shankland SJ, Alpers CE, Najafian B, Vaughan JC. Volumetric, Nanoscale Optical Imaging of Mouse and Human Kidney via Expansion Microscopy. Sci Rep 2018; 8:10396. [PMID: 29991751 PMCID: PMC6039510 DOI: 10.1038/s41598-018-28694-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 06/21/2018] [Indexed: 01/19/2023] Open
Abstract
Although light microscopy is a powerful tool for the assessment of kidney physiology and pathology, it has traditionally been unable to resolve structures separated by less than the ~250 nm diffraction limit of visible light. Here, we report on the optimization, validation, and application of a recently developed super-resolution fluorescence microscopy method, called expansion microscopy (ExM), for volumetric interrogation of mouse and human kidney tissue with 70-75 nm lateral and ~250 nm axial spatial resolution. Using ExM with a standard confocal microscope, we resolve fine details of structures that have traditionally required visualization by electron microscopy, including podocyte foot processes, the glomerular basement membrane, and the cytoskeleton. This inexpensive and accessible approach to volumetric, nanoscale imaging enables visualization of fine structural details of kidney tissues that were previously difficult or impossible to measure by conventional methodologies.
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Affiliation(s)
- Tyler J Chozinski
- Department of Chemistry, University of Washington, Seattle, Washington, 98195, USA
| | - Chenyi Mao
- Department of Chemistry, University of Washington, Seattle, Washington, 98195, USA
| | - Aaron R Halpern
- Department of Chemistry, University of Washington, Seattle, Washington, 98195, USA
| | - Jeffrey W Pippin
- Department of Medicine, Division of Nephrology, University of Washington, Seattle, Washington, 98195, USA
| | - Stuart J Shankland
- Department of Medicine, Division of Nephrology, University of Washington, Seattle, Washington, 98195, USA
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, Washington, 98195, USA
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, Washington, 98195, USA
| | - Joshua C Vaughan
- Department of Chemistry, University of Washington, Seattle, Washington, 98195, USA.
- Department of Physiology and Biophysics, University of Washington, Seattle, Washington, 98195, USA.
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Alpers CE, Hudkins KL. Pathology identifies glomerular treatment targets in diabetic nephropathy. Kidney Res Clin Pract 2018; 37:106-111. [PMID: 29971205 PMCID: PMC6027807 DOI: 10.23876/j.krcp.2018.37.2.106] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 05/30/2018] [Accepted: 06/01/2018] [Indexed: 12/29/2022] Open
Abstract
The development of the glomerular injury in diabetic nephropathy involves interactions between podocytes, endothelium, and the mesangium. Loss of podocytes is an early and critical step in the development of diabetic nephropathy, and analysis of structural lesions within the mesangium such as mesangiolysis implicate the loss of podocytes as a key mediating event. The BTBR ob/ob mouse has proved a useful tool to demonstrate that restoration of podocyte density, once thought to be an absolute barrier to glomerular repair, can be achieved with replacement of the hormone leptin that is constitutively absent in these mice. Restoration of podocyte density is associated with reversal of the structural lesions of morphologically advanced diabetic glomerular injury in this model. This finding, in conjunction with the demonstration in human diabetic patients with morphologically advanced diabetic nephropathy and with long-standing functioning pancreatic transplants of ten years duration that their diabetic nephropathy can be reversed, suggests that restoration of podocyte number and density is an appropriate target for the development of new therapeutics for diabetic nephropathy.
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Affiliation(s)
- Charles E Alpers
- Department of Pathology, University of Washington, Seattle, WA, USA
| | - Kelly L Hudkins
- Department of Pathology, University of Washington, Seattle, WA, USA
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49
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Arkatkar T, Jacobs HM, Du SW, Li QZ, Hudkins KL, Alpers CE, Rawlings DJ, Jackson SW. TACI deletion protects against progressive murine lupus nephritis induced by BAFF overexpression. Kidney Int 2018; 94:728-740. [PMID: 29907458 DOI: 10.1016/j.kint.2018.03.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 03/12/2018] [Accepted: 03/15/2018] [Indexed: 11/26/2022]
Abstract
B cells are known to promote the pathogenesis of systemic lupus erythematosus (SLE) via the production of pathogenic anti-nuclear antibodies. However, the signals required for autoreactive B cell activation and the immune mechanisms whereby B cells impact lupus nephritis pathology remain poorly understood. The B cell survival cytokine B cell activating factor of the TNF Family (BAFF) has been implicated in the pathogenesis of SLE and lupus nephritis in both animal models and human clinical studies. Although the BAFF receptor has been predicted to be the primary BAFF family receptor responsible for BAFF-driven humoral autoimmunity, in the current study we identify a critical role for signals downstream of Transmembrane Activator and CAML Interactor (TACI) in BAFF-dependent lupus nephritis. Whereas transgenic mice overexpressing BAFF develop progressive membranoproliferative glomerulonephritis, albuminuria and renal dysfunction, TACI deletion in BAFF-transgenic mice provided long-term (about 1 year) protection from renal disease. Surprisingly, disease protection in this context was not explained by complete loss of glomerular immune complex deposits. Rather, TACI deletion specifically reduced endocapillary, but not mesangial, immune deposits. Notably, although excess BAFF promoted widespread breaks in B cell tolerance, BAFF-transgenic antibodies were enriched for RNA- relative to DNA-associated autoantigen reactivity. These RNA-associated autoantibody specificities were specifically reduced by TACI or Toll-like receptor 7 deletion. Thus, our study provides important insights into the autoantibody specificities driving proliferative lupus nephritis, and suggests that TACI inhibition may be novel and effective treatment strategy in lupus nephritis.
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Affiliation(s)
- Tanvi Arkatkar
- Seattle Children's Research Institute, Seattle, Washington, USA
| | - Holly M Jacobs
- Seattle Children's Research Institute, Seattle, Washington, USA
| | - Samuel W Du
- Seattle Children's Research Institute, Seattle, Washington, USA
| | - Quan-Zhen Li
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Kelly L Hudkins
- Department of Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Charles E Alpers
- Department of Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - David J Rawlings
- Seattle Children's Research Institute, Seattle, Washington, USA; Department of Pathology, University of Washington School of Medicine, Seattle, Washington, USA; Department of Immunology, University of Washington School of Medicine, Seattle, Washington, USA; Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington, USA
| | - Shaun W Jackson
- Seattle Children's Research Institute, Seattle, Washington, USA; Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington, USA.
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50
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Allon M, Imrey PB, Cheung AK, Radeva M, Alpers CE, Beck GJ, Dember LM, Farber A, Greene T, Himmelfarb J, Huber TS, Kaufman JS, Kusek JW, Roy-Chaudhury P, Robbin ML, Vazquez MA, Feldman HI. Relationships Between Clinical Processes and Arteriovenous Fistula Cannulation and Maturation: A Multicenter Prospective Cohort Study. Am J Kidney Dis 2018; 71:677-689. [PMID: 29398178 PMCID: PMC5916528 DOI: 10.1053/j.ajkd.2017.10.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 10/31/2017] [Indexed: 02/08/2023]
Abstract
BACKGROUND Half of surgically created arteriovenous fistulas (AVFs) require additional intervention to effectively support hemodialysis. Postoperative care and complications may affect clinical maturation. STUDY DESIGN Hemodialysis Fistula Maturation (HFM) Study, a 7-center prospective cohort study. SETTING & PARTICIPANTS 491 patients with single-stage AVFs who had neither thrombosis nor AVF intervention before a 6-week postoperative ultrasonographic examination and who required maintenance hemodialysis. PREDICTORS Postoperative care processes and complications. OUTCOMES Attempted cannulation, successful cannulation, and unassisted and overall clinical maturation as defined by the HFM Study criteria. RESULTS AVF cannulation was attempted in 443 of 491 (90.2%) participants and was eventually successful in 430 of these 443 (97.1%) participants. 263 of these 430 (61.2%) reached unassisted and 118 (27.4%) reached assisted AVF maturation (overall maturation, 381/430 [88.6%]). Attempted cannulation was less likely in patients of surgeons with policies for routine 2-week versus later-than-2-week first postoperative visits (OR, 0.21; 95% CI, 0.06-0.70), routine second postoperative follow-up visits (OR, 0.39; 95% CI, 0.15-0.97), and a routine clinical postoperative ultrasound (OR, 0.28; 95% CI, 0.14-0.55). Attempted cannulation was also less likely among patients undergoing procedures to assist maturation (OR, 0.51; 95% CI, 0.27-0.98). Unassisted maturation was more likely for patients treated in facilities with access coordinators (OR, 1.91; 95% CI, 1.17-3.12), but less likely after precannulation nonstudy ultrasounds (OR per ultrasound, 0.42 [95% CI, 0.26-0.68]) and initial unsuccessful cannulation attempts (OR per each additional attempt, 0.90 [95% CI, 0.83-0.98]). Overall maturation was less likely with infiltration before successful cannulation (OR, 0.44; 95% CI, 0.22-0.89). Among participants receiving maintenance hemodialysis before AVF surgery, unassisted and overall maturation were less likely with longer intervals from surgery to initial cannulation (ORs for each additional month of 0.81 [95% CI, 0.76-0.88] and 0.93 [95% CI, 0.89-0.98], respectively) and from initial to successful cannulation (ORs for each additional week of 0.87 [95% CI, 0.81-0.94] and 0.88 [95% CI, 0.83-0.94], respectively). LIMITATIONS Surgeons' management policies were assessed only by questionnaire at study onset. Most participants received upper-arm AVFs, planned 2-stage AVFs were excluded, and maturation time windows were imposed. Some care processes may have been missed and the observational design limits causal attribution. CONCLUSIONS Multiple processes of care and complications are associated with AVF maturation outcomes.
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Affiliation(s)
- Michael Allon
- Division of Nephrology, University of Alabama at Birmingham, Birmingham, AL.
| | - Peter B Imrey
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University; Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH
| | - Alfred K Cheung
- Division of Nephrology & Hypertension, University of Utah and Veterans Affairs Salt Lake City Healthcare System, Salt Lake City, UT; Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Milena Radeva
- Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH
| | - Charles E Alpers
- Department of Pathology, University of Washington Medical Center, Seattle, WA
| | - Gerald J Beck
- Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH
| | - Laura M Dember
- Renal-Electrolyte and Hypertension Division, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA; Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA; Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
| | - Alik Farber
- Division of Vascular and Endovascular Surgery, Boston Medical Center, Boston, MA
| | - Tom Greene
- Division of Epidemiology, University of Utah, Salt Lake City, UT
| | - Jonathan Himmelfarb
- Kidney Research Institute, Department of Medicine, University of Washington, Seattle, WA
| | - Thomas S Huber
- Division of Vascular Surgery, University of Florida College of Medicine, Gainesville, FL
| | - James S Kaufman
- VA New York Harbor Healthcare System and New York University School of Medicine, New York, NY
| | - John W Kusek
- Division of Kidney, Urologic and Hematologic Diseases, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD
| | | | - Michelle L Robbin
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL
| | - Miguel A Vazquez
- Division of Nephrology, University of Texas Southwestern, Dallas, TX
| | - Harold I Feldman
- Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA; Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA; Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
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