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Afolabi H, Zhang BM, O'Shaughnessy M, Chertow GM, Lafayette R, Charu V. The Association of Class I and II Human Leukocyte Antigen Serotypes With End-Stage Kidney Disease Due to Membranoproliferative Glomerulonephritis and Dense Deposit Disease. Am J Kidney Dis 2024; 83:79-89. [PMID: 37739026 DOI: 10.1053/j.ajkd.2023.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 05/24/2023] [Accepted: 06/06/2023] [Indexed: 09/24/2023]
Abstract
RATIONALE & OBJECTIVE Membranoproliferative glomerulonephritis (MPGN), encompassing several distinct diseases, is a rare but significant cause of kidney failure in the United States. The potential etiologies of MPGN are unclear, but prior studies have suggested dysregulation of the alternative complement pathway and, recently, autoimmunity as potential mechanisms driving MPGN pathogenesis. In this study, we examined HLA associations with end-stage kidney disease (ESKD) due to MPGN and dense deposit disease (DDD) in a large racially and ethnically diverse US-based cohort. STUDY DESIGN Case-control study. SETTING & PARTICIPANTS Using US Renal Data System (USRDS) and United Network for Organ Sharing (UNOS) data, we identified 3,424 patients with kidney failure due to MPGN and 263 due to DDD. We matched patients to kidney donor controls on designated race and ethnicity in a 1:15 ratio. EXPOSURE 58 class I and II HLA serotypes. OUTCOME Case-control status. ANALYTICAL APPROACH For each disease cohort, univariable and multivariable logistic regression analyses were used to investigate associations between the disease and 58 HLA serotypes. In subgroup analyses, we investigated HLA associations in White and Black patients. We also studied antiglomerular basement membrane (anti-GBM) nephritis as a positive-control outcome. We applied a Bonferroni correction to account for multiple comparisons. RESULTS Eighteen serotypes were significantly associated with the odds of having MPGN in univariable analyses, with DR17 having the strongest association (odds ratio [OR], 1.55 [95% CI, 1.44-1.68], P=4.33e-28). No significant associations were found between any HLA serotype and DDD. Designated race-specific analyses showed comparable findings. We recapitulated known HLA associations in anti-GBM nephritis. LIMITATIONS Reliance on HLA serotypes (rather than genotype), lack of biopsy-confirmed diagnoses. CONCLUSIONS HLA-DR17 is associated with ESKD due to MPGN in a racially and ethnically diverse cohort. The strength of association was similar in White and Black patients, suggesting a role in the pathogenesis of MPGN. No HLA associations were observed in patients with DDD. PLAIN-LANGUAGE SUMMARY Prior studies have suggested dysregulation of the alternative complement pathway as a potential etiology of membranoproliferative glomerulonephritis (MPGN), but recent evidence from a British White population has implicated an autoimmune mechanism in MPGN pathogenesis. We investigated HLA associations between MPGN and dense deposit disease (DDD) in a large racially and ethnically diverse cohort of patients. We found that HLA-DR17 is associated with end-stage kidney disease (ESKD) due to MPGN in both White and Black patients. By contrast, no significant HLA associations with ESKD due to DDD were identified. These results suggest a role for autoimmunity in some cases of MPGN and highlight differences in the disease etiology of MPGN compared with DDD.
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Affiliation(s)
- Halimat Afolabi
- Department of Pathology, Department of Medicine, School of Medicine, Stanford University, Stanford, California
| | - Bing M Zhang
- Department of Pathology, Department of Medicine, School of Medicine, Stanford University, Stanford, California
| | | | - Glenn M Chertow
- Division of Nephrology, Department of Medicine, School of Medicine, Stanford University, Stanford, California
| | - Richard Lafayette
- Division of Nephrology, Department of Medicine, School of Medicine, Stanford University, Stanford, California
| | - Vivek Charu
- Department of Pathology, Department of Medicine, School of Medicine, Stanford University, Stanford, California; Department of Medicine and Quantitative Sciences Unit, Department of Medicine, School of Medicine, Stanford University, Stanford, California.
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Miller P, Caza T. The expanding spectrum and utility of antigens in membranous nephropathy. Curr Opin Nephrol Hypertens 2023; 32:232-240. [PMID: 36811646 DOI: 10.1097/mnh.0000000000000876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
PURPOSE OF REVIEW Multiple antigenic targets were discovered in membranous nephropathy, representing distinct autoimmune diseases with a similar morphologic pattern of injury. An overview of recent developments, including antigen types, clinical associations, serologic monitoring, and advancements in understanding disease pathogenesis are provided. RECENT FINDINGS Several new antigenic targets have defined subtypes of membranous nephropathy, including Neural epidermal growth factor-like 1, protocadherin 7, HTRA1, FAT1, SEMA3B, NTNG1, NCAM1, exostosin 1/2, transforming growth factor beta receptor 3, CNTN1, proprotein convertase subtilisin/kexin type 6, and neuron-derived neurotrophic factor. Autoantigens in membranous nephropathy may demonstrate unique clinical associations, assisting the nephrologist to identify potential disease etiologies and triggers, such as autoimmune disease, cancer, medications, and infections. SUMMARY We are entering an exciting era for which an antigen-based approach will further define subtypes of membranous nephropathy, allow for development of noninvasive diagnostics, and improve care for patients.
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Affiliation(s)
- Paul Miller
- Arkana Laboratories, Little Rock, Arkansas, USA
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Wu M, Chen Y, Chiu I, Wu M. Genetic Insight into Primary Glomerulonephritis. Nephrology (Carlton) 2022; 27:649-657. [DOI: 10.1111/nep.14074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 04/18/2022] [Accepted: 06/06/2022] [Indexed: 11/28/2022]
Affiliation(s)
- Mei‐Yi Wu
- Division of Nephrology, Department of Internal Medicine Taipei Medical University‐Shuang Ho Hospital New Taipei City Taiwan
- Division of Nephrology, Department of Internal Medicine, School of Medicine, College of Medicine Taipei Medical University Taipei Taiwan
- Institute of Epidemiology and Preventive Medicine, College of Public Health National Taiwan University Taipei Taiwan
- TMU Research Center of Urology and Kidney Taipei Medical University Taipei Taiwan
| | - Ying‐Chun Chen
- Division of Nephrology, Department of Internal Medicine Taipei Medical University‐Shuang Ho Hospital New Taipei City Taiwan
| | - I‐Jen Chiu
- Division of Nephrology, Department of Internal Medicine Taipei Medical University‐Shuang Ho Hospital New Taipei City Taiwan
- Division of Nephrology, Department of Internal Medicine, School of Medicine, College of Medicine Taipei Medical University Taipei Taiwan
- TMU Research Center of Urology and Kidney Taipei Medical University Taipei Taiwan
| | - Mai‐Szu Wu
- Division of Nephrology, Department of Internal Medicine Taipei Medical University‐Shuang Ho Hospital New Taipei City Taiwan
- Division of Nephrology, Department of Internal Medicine, School of Medicine, College of Medicine Taipei Medical University Taipei Taiwan
- TMU Research Center of Urology and Kidney Taipei Medical University Taipei Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine Taipei Medical University Taipei Taiwan
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Membranous nephropathy: new pathogenic mechanisms and their clinical implications. Nat Rev Nephrol 2022; 18:466-478. [PMID: 35484394 DOI: 10.1038/s41581-022-00564-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2022] [Indexed: 12/24/2022]
Abstract
Membranous nephropathy (MN) is characterized histomorphologically by the presence of immune deposits in the subepithelial space of the glomerular filtration barrier; its clinical hallmarks are nephrotic range proteinuria with oedema. In patients with primary MN, autoimmunity is driven by circulating autoantibodies that bind to one or more antigens on the surface of glomerular podocytes. Compared with other autoimmune kidney diseases, the understanding of the pathogenesis of MN has substantially improved in the past decade, thanks to the discovery of pathogenic circulating autoantibodies against phospholipase A2 receptor 1 (PLA2R1) and thrombospondin type 1 domain-containing protein 7A (THSD7A). The subsequent identification of more proteins associated with MN, some of which are also endogenous podocyte antigens, might further advance the clinical characterization of MN, including its diagnosis, treatment and prognosis. Insights from studies in patients with MN, combined with the development of novel in vivo and in vitro experimental models, have potential to improve the management of patients with MN. Characterizing the interaction between autoimmunity and local glomerular lesions provides an opportunity to develop more specific, pathogenesis-based treatments.
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Zanoni F, Khairallah P, Kiryluk K, Batal I. Glomerular Diseases of the Kidney Allograft: Toward a Precision Medicine Approach. Semin Nephrol 2022; 42:29-43. [PMID: 35618394 PMCID: PMC9139085 DOI: 10.1016/j.semnephrol.2022.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The continual development of potent immunosuppressive regimens has led to a decreased incidence of acute rejection and improvement of short-term kidney allograft survival. In contrast to acute rejection, glomerular diseases of the kidney allograft are being encountered more frequently and are emerging as leading causes of late kidney allograft failure. Although data on the pathogeneses of glomerular diseases in the kidney allograft are sparse, cumulative evidence suggests that post-transplant glomerular diseases may be the result of inherited predispositions and immunologic triggers. Although studying immunologic signals and performing genome-wide association studies are ideal approaches to tackle glomerular diseases in the kidney allograft, such studies are challenging because of the lack of adequately powered cohorts. In this review, we focus on the most commonly encountered recurrent and de novo glomerular diseases in the kidney allograft. We address the important advances made in understanding the immunopathology and genetic susceptibility of glomerular diseases in the native kidney and how to benefit from such knowledge to further our knowledge of post-transplant glomerular diseases. Defining genomic and immune predictors for glomerular diseases in the kidney allograft would support novel donor-recipient matching strategies and development of targeted therapies to ultimately improve long-term kidney allograft survival.
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Affiliation(s)
- Francesca Zanoni
- Medicine, Nephrology, Columbia University Irving Medical Center, New York, NY, USA
| | | | - Krzysztof Kiryluk
- Medicine, Nephrology, Columbia University Irving Medical Center, New York, NY, USA
| | - Ibrahim Batal
- Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA,Corresponding Author: Ibrahim Batal MD, Department of Pathology and Cell Biology, Renal Division, Columbia University Irving Medical Center, 630 W 168th street, VC14-238, New York, NY 10032, Phone: 212-305-9669, Fax: 212-342-5380,
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Caza TN, Al-Rabadi LF, Beck LH. How Times Have Changed! A Cornucopia of Antigens for Membranous Nephropathy. Front Immunol 2021; 12:800242. [PMID: 34899763 PMCID: PMC8662735 DOI: 10.3389/fimmu.2021.800242] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 11/09/2021] [Indexed: 11/13/2022] Open
Abstract
The identification of the major target antigen phospholipase A2 receptor (PLA2R) in the majority of primary (idiopathic) cases of membranous nephropathy (MN) has been followed by the rapid identification of numerous minor antigens that appear to define phenotypically distinct forms of disease. This article serves to review all the known antigens that have been shown to localize to subepithelial deposits in MN, as well as the distinctive characteristics associated with each subtype of MN. We will also shed light on the novel proteomic approaches that have allowed identification of the most recent antigens. The paradigm of an antigen normally expressed on the podocyte cell surface leading to in-situ immune complex formation, complement activation, and subsequent podocyte injury will be discussed and challenged in light of the current repertoire of multiple MN antigens. Since disease phenotypes associated with each individual target antigens can often blur the distinction between primary and secondary disease, we encourage the use of antigen-based classification of membranous nephropathy.
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Affiliation(s)
| | - Laith F. Al-Rabadi
- Department of Internal Medicine (Nephrology & Hypertension), University of Utah, Salt Lake City, UT, United States
| | - Laurence H. Beck
- Department of Medicine (Nephrology), Boston University School of Medicine and Boston Medical Center, Boston, MA, United States
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Liu W, Huang G, Rui H, Geng J, Hu H, Huang Y, Huo G, Liu B, Xu A. Course monitoring of membranous nephropathy: Both autoantibodies and podocytes require multidimensional attention. Autoimmun Rev 2021; 21:102976. [PMID: 34757091 DOI: 10.1016/j.autrev.2021.102976] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/18/2021] [Accepted: 10/24/2021] [Indexed: 01/15/2023]
Abstract
A variety of podocyte antigens have been identified in human membranous nephropathy (MN), which is divided into various antigen-dominated subtypes, confirming the concept that MN is the common pattern of glomerular injury in multiple autoimmune responses. The detection of autoantibodies has been widely used, which promoted the clinical practice of MN toward personalized precision medicine. However, given the potential risks of immunosuppressive therapy, more autoantibodies and biomarkers need to be identified to predict the prognosis and therapeutic response of MN more accurately. In this review, we attempted to summarize the autoantigens/autoantibodies and autoimmune mechanisms that can predict disease states based on the current understanding of MN pathogenesis, especially the podocyte injury manifestations. In conclusion, both the autoimmune response and podocyte injury require multidimensional attention in the disease course of MN.
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Affiliation(s)
- Wenbin Liu
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China
| | - Guangrui Huang
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China
| | - Hongliang Rui
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Jie Geng
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China
| | - Haikun Hu
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China
| | - Yujiao Huang
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China
| | - Guiyang Huo
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China
| | - Baoli Liu
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.
| | - Anlong Xu
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China.
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Novel insights in the genetics of steroid-sensitive nephrotic syndrome in childhood. Pediatr Nephrol 2021; 36:2165-2175. [PMID: 33084934 DOI: 10.1007/s00467-020-04780-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/10/2020] [Accepted: 09/14/2020] [Indexed: 10/23/2022]
Abstract
Steroid-sensitive nephrotic syndrome (SSNS) is the most common form of nephrotic syndrome in childhood and there is growing evidence that genetics play a role in the susceptibility for the disease. Familial clustering has been observed and has led to several studies on familial SSNS trying to identify a monogenic cause of the disease. Until now, however, none of these have provided convincing evidence for Mendelian inheritance. This and the phenotypic variability within SSNS suggest a complex inheritance pattern, where multiple variants and interactions between those and the environment play roles in disease development. Genome-wide association studies (GWASs) have been used to investigate this complex disease. We herein highlight new insights in the genetics of the disease provided by GWAS and identify how these insights fit into our understanding of the pathogenesis of SSNS.
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Le WB, Shi JS, Fan Y, Gong SW. HLA Alleles and Prognosis of PLA2R-Related Membranous Nephropathy. Clin J Am Soc Nephrol 2021; 16:1221-1227. [PMID: 34083219 PMCID: PMC8455041 DOI: 10.2215/cjn.18021120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 05/05/2021] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND OBJECTIVES Associations between HLA alleles and susceptibility to M-type phospholipase A2 receptor (PLA2R)-related membranous nephropathy have been well defined previously in Chinese patients. However, the relationships between HLA alleles and kidney outcome remain unclear. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Five HLA genes (DRB1, DQA1, DQB1, DRB3, and DRB5) were genotyped in a prospective cohort of 392 patients with PLA2R-related membranous nephropathy. The associations between HLA alleles and kidney outcomes were studied. RESULTS A total of 79 HLA alleles were identified in this study. Four HLA alleles, DRB1*13:01 (n=12; hazard ratio, 3.7; 95% confidence interval, 1.8 to 7.8; P<0.001), DQB1*06:03 (n=12; hazard ratio, 3.7; 95% confidence interval, 1.8 to 7.8; P<0.001), DRB1*04:05 (n=12; hazard ratio, 3.8; 95% confidence interval, 1.5 to 9.5; P=0.004), and DQB1*03:02 (n=21; hazard ratio, 3.1; 95% confidence interval, 1.4 to 6.7; P=0.005), were associated with a ≥40% eGFR decline during follow-up. DRB1*13:01 and DQB1*06:03 were tightly linked with each other. Forty-four of the 392 patients (11%) carried at least one of the four identified risk HLA alleles in this study. Compared with patients who were negative for all risk HLA alleles, those carrying at least one risk HLA allele had a significant risk of a ≥40% eGFR decline during follow-up (hazard ratio, 3.9; 95% confidence interval, 2.3 to 6.7; P<0.001). After adjusting for age, sex, proteinuria, albumin, eGFR, and anti-PLA2R antibody levels, multivariable Cox analysis showed that patients carrying any of the four risk HLA alleles remained associated with a higher risk of a ≥40% decline in eGFR (hazard ratio, 4.1; 95% confidence interval, 2.3 to 7.1; P<0.001). CONCLUSIONS Carrying any of the HLA alleles, DRB1*13:01/DQB1*06:03, DRB1*04:05, and DQB1*03:02, was independently associated with poor prognosis in Chinese patients with PLA2R-related membranous nephropathy.
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Affiliation(s)
- Wei-Bo Le
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Jing-Song Shi
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Yang Fan
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Si-Wen Gong
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, The First School of Clinical Medicine, Southern Medical University, Nanjing, China
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A Novel Insight into the Role of PLA2R and THSD7A in Membranous Nephropathy. J Immunol Res 2021; 2021:8163298. [PMID: 34337081 PMCID: PMC8298181 DOI: 10.1155/2021/8163298] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 06/20/2021] [Accepted: 07/03/2021] [Indexed: 12/22/2022] Open
Abstract
Membranous nephropathy (MN) is an organ-restricted autoimmune disease mainly caused by circulating autoantibodies against podocyte antigens, including the M-type phospholipase A2 receptor (PLA2R) and thrombospondin domain-containing 7A (THSD7A). Antibodies against PLA2R are present in 70%-80% and against THSD7A in 2% of adult patients, which provides a paradigm shift in molecular diagnosis and management monitoring. Both antigens share some similar characteristics: they are expressed by podocytes and have wide tissue distributions; they are bound by autoantibodies only under nonreducing conditions, and the subtype of most autoantibodies is IgG4. However, the factors triggering autoantibody production as well as the association among air pollution, malignancy, and the pathogenesis of MN remain unclear. In this review, we discuss the similarity between the pathological mechanisms triggered by disparate antigens and their associated diseases. Furthermore, we demonstrated the possibility that PM2.5, malignancy, and gene expression specifically induce exposure of these antigens through conformational changes, molecular mimicry, or increased expression eliciting autoimmune responses. Thus, this review provides novel insights into the pathological mechanism of MN.
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Abstract
The identification of the phospholipase A2 receptor 1 (PLA2R) and thrombospondin type-1 domain-containing protein 7A (THSD7A) as podocyte antigens in adult patients with membranous nephropathy (MN) has strongly impacted both experimental and clinical research on this disease. Evidence has been furnished that podocyte-directed autoantibodies can cause MN, and novel PLA2R- and THSD7A-specific animal models have been developed. Today, measurement of serum autoantibody levels and staining of kidney biopsies for the target antigens guides MN diagnosis and treatment worldwide. Additionally, anti-PLA2R antibodies have been proven to be valuable prognostic biomarkers in MN. Despite these impressive advances, a variety of questions regarding the disease pathomechanisms, clinical use of antibody measurement, and future treatments remain unanswered. In this review, we will outline recent advances made in the field of MN and discuss open questions and perspectives with a focus on novel antigen identification, mechanisms of podocyte injury, clinical use of antibody measurement to guide diagnosis and treatment, and the potential of innovative, pathogenesis-based treatment strategies.
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Mechanisms of Primary Membranous Nephropathy. Biomolecules 2021; 11:biom11040513. [PMID: 33808418 PMCID: PMC8065962 DOI: 10.3390/biom11040513] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/23/2021] [Accepted: 03/26/2021] [Indexed: 12/11/2022] Open
Abstract
Membranous nephropathy (MN) is an autoimmune disease of the kidney glomerulus and one of the leading causes of nephrotic syndrome. The disease exhibits heterogenous outcomes with approximately 30% of cases progressing to end-stage renal disease. The clinical management of MN has steadily advanced owing to the identification of autoantibodies to the phospholipase A2 receptor (PLA2R) in 2009 and thrombospondin domain-containing 7A (THSD7A) in 2014 on the podocyte surface. Approximately 50–80% and 3–5% of primary MN (PMN) cases are associated with either anti-PLA2R or anti-THSD7A antibodies, respectively. The presence of these autoantibodies is used for MN diagnosis; antibody levels correlate with disease severity and possess significant biomarker values in monitoring disease progression and treatment response. Importantly, both autoantibodies are causative to MN. Additionally, evidence is emerging that NELL-1 is associated with 5–10% of PMN cases that are PLA2R- and THSD7A-negative, which moves us one step closer to mapping out the full spectrum of PMN antigens. Recent developments suggest exostosin 1 (EXT1), EXT2, NELL-1, and contactin 1 (CNTN1) are associated with MN. Genetic factors and other mechanisms are in place to regulate these factors and may contribute to MN pathogenesis. This review will discuss recent developments over the past 5 years.
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Sanchez-Rodriguez E, Southard CT, Kiryluk K. GWAS-Based Discoveries in IgA Nephropathy, Membranous Nephropathy, and Steroid-Sensitive Nephrotic Syndrome. Clin J Am Soc Nephrol 2021; 16:458-466. [PMID: 32680915 PMCID: PMC8011010 DOI: 10.2215/cjn.14031119] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Over the past decade, genome-wide association studies (GWAS) have emerged as a powerful tool to understand the genetic basis of complex traits in humans. The GWAS approach has been successfully applied to primary glomerular disorders, providing numerous novel insights into the genetic architecture of IgA nephropathy, membranous nephropathy, and steroid-sensitive nephrotic syndrome. IgA nephropathy appears to have a highly complex polygenic architecture, with nearly 20 genome-wide significant loci of small-to-moderate effects discovered to date. In contrast, the genetic susceptibility to membranous nephropathy and steroid-sensitive nephrotic syndrome appears to be driven by a small number of large-effect loci. The MHC locus on chromosome 6p21 is strongly associated with genetic susceptibility to all major types of immune-mediated glomerulopathies. However, a distinct set of classical HLA alleles is associated with each individual disease type, pinpointing to specific immune mechanisms underlying each of these conditions. Additional insights from the discovery of non-HLA risk loci reinforced the role of innate and adaptive immunity in the pathogenesis of these disorders, and highlighted important susceptibility overlaps between glomerular and other autoimmune and inflammatory conditions. Despite these initial successes, much larger GWAS and sequencing studies are still needed for each individual glomerular disease type. Increased power will be critical to comprehensively test for genetic effects across the full spectrum of allelic frequencies, to detect gene-gene and gene-environment interactions, and to potentially improve the performance of polygenic risk predictors. Moreover, the existing studies are limited mostly to European and East Asian populations, stressing the urgency to expand genetic discovery efforts to more diverse populations worldwide.
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Affiliation(s)
- Elena Sanchez-Rodriguez
- Division of Nephrology, Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York
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Berchtold L, Letouzé E, Alexander MP, Canaud G, Logt AEVD, Hamilton P, Mousson C, Vuiblet V, Moyer AM, Guibert S, Mrázová P, Levi C, Dubois V, Cruzado JM, Torres A, Gandhi MJ, Yousfi N, Tesar V, Viklický O, Hourmant M, Moulin B, Rieu P, Choukroun G, Legendre C, Wetzels J, Brenchley P, Ballarín Castan JA, Debiec H, Ronco P. HLA-D and PLA2R1 risk alleles associate with recurrent primary membranous nephropathy in kidney transplant recipients. Kidney Int 2021; 99:671-685. [DOI: 10.1016/j.kint.2020.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/30/2020] [Accepted: 08/13/2020] [Indexed: 12/22/2022]
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Wu L, Lai J, Ling Y, Weng Y, Zhou S, Wu S, Jiang S, Ding X, Jin X, Yu K, Chen Y. A Review of the Current Practice of Diagnosis and Treatment of Idiopathic Membranous Nephropathy in China. Med Sci Monit 2021; 27:e930097. [PMID: 33550324 PMCID: PMC7876949 DOI: 10.12659/msm.930097] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Idiopathic membranous nephropathy (IMN), a common pathological type of nephrotic syndrome, is one of the main causes of kidney failure. With an increasing prevalence, IMN has received considerable attention in China. Based on recent studies, we discuss advances in the diagnosis of IMN and the understanding of its genetic background. Although the pathogenesis of IMN remains unclear, our understanding has been substantially enhanced by the discovery of new antigens such as phospholipase A2 receptor, thrombospondin type-1 domain-containing 7A, exostosin1/exostosin2, neural epidermal growth factor-like 1 protein, neural cell adhesion molecule 1, semaphorin 3B, and factor H autoantibody. However, due to ethnic, environmental, economic, and lifestyle differences and other factors, a consensus has not yet been reached regarding IMN treatment. In view of the differences between Eastern and Western populations, in-depth clinical evaluations of biomarkers for IMN diagnosis are necessary. This review details the current treatment strategies for IMN in China, including renin-angiotensin system inhibitors, corticosteroid monotherapy, cyclophosphamide, calcineurin inhibitors, mycophenolate mofetil, adrenocorticotropic hormone, and traditional Chinese medicine, as well as biological preparations such as rituximab. In terms of management, the 2012 Kidney Disease Improving Global Outcomes (KDIGO) clinical practice guidelines do not fully consider the characteristics of the Chinese population. Therefore, this review aims to present the current status of IMN diagnosis and treatment in Chinese patients, and includes a discussion of new approaches and remaining clinical challenges.
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Affiliation(s)
- Lianzhong Wu
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland).,Department of Hematology, Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
| | - Jin Lai
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland).,Department of Hematology, Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
| | - Yixin Ling
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland).,Department of Hematology, Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
| | - Yiqin Weng
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland).,Department of Hematology, Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
| | - Shujuan Zhou
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
| | - Siqi Wu
- Department of Hematology, Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
| | - Songfu Jiang
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
| | - Xiaokai Ding
- Department of Nephrology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
| | - Xin Jin
- Department of Clinical Laboratory, Tongde Hospital of Zhejiang Province, Hangzhou, Zhejiang, China (mainland)
| | - Kang Yu
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
| | - Yi Chen
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China (mainland)
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16
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Edmonston DL, Roe MT, Block G, Conway PT, Dember LM, DiBattiste PM, Greene T, Hariri A, Inker LA, Isakova T, Montez-Rath ME, Nkulikiyinka R, Polidori D, Roessig L, Tangri N, Wyatt C, Chertow GM, Wolf M. Drug Development in Kidney Disease: Proceedings From a Multistakeholder Conference. Am J Kidney Dis 2020; 76:842-850. [DOI: 10.1053/j.ajkd.2020.05.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 05/27/2020] [Indexed: 01/02/2023]
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17
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Cremoni M, Brglez V, Perez S, Decoupigny F, Zorzi K, Andreani M, Gérard A, Boyer-Suavet S, Ruetsch C, Benzaken S, Esnault V, Seitz-Polski B. Th17-Immune Response in Patients With Membranous Nephropathy Is Associated With Thrombosis and Relapses. Front Immunol 2020; 11:574997. [PMID: 33324398 PMCID: PMC7725714 DOI: 10.3389/fimmu.2020.574997] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 10/28/2020] [Indexed: 12/30/2022] Open
Abstract
Membranous nephropathy (MN) is a rare autoimmune kidney disease. Most autoimmune diseases are associated with a pro-inflammatory Th17-immune response, but little is known about immune dysregulation in MN. In China, MN was associated with exposure to fine air particulate matter (PM2.5) that could act as a danger signal and redirect immune response toward the Th2 or Th17 pathway. We aimed to analyze the cytokine profile of MN patients and to study the possible environmental factors involved in this immune reorientation, as well as the consequences on the prognosis of the disease. In this prospective study, 59 MN patients filled a comprehensive lifestyle questionnaire. Peripheral blood cells from MN patients were stimulated in vitro to measure the cytokines produced in supernatant. Cytokine profiles of MN patients were compared to 28 healthy donors and analyzed regarding individual PM2.5 exposure. Compared to healthy donors, MN patients had higher serum levels of Th17 and Th2 cytokines IL-17A (62 pg/ml [IQR, 16–160] versus 31 [IQR, 13–51], P=0.035), IL-6 (66767 pg/ml [IQR, 36860–120978] versus 27979 [IQR, 18672–51499], P=0.001), and IL-4 (12 pg/ml [IQR, 0–33] versus 0 pg/ml [IQR, 0–0], P=0.0003), respectively, as well as a deficiency of Th1 and regulatory T cell cytokines IFN-γ (5320 pg/ml [IQR, 501–14325] versus 18037 [IQR, 4889–31329], P=0.0005) and IL-10 (778 pg/ml [IQR, 340–1247] versus 1102 [IQR, 737–1652], P=0.04), respectively. MN patients with high IL-17A levels lived in areas highly exposed to PM2.5: 51 μg/m3 versus 31 μg/m3 for patients with low IL-17A levels (P=0.002) while the World Health Organization recommends an exposition below 10 μg/m3. MN patients with Th17-mediated inflammation had more venous thromboembolic events (P=0.03) and relapsed more often (P=0.0006). Rituximab treatment induced Th1 and regulatory T cell cytokines but did not impact Th17 cytokines. MN patients with Th17-mediated inflammation which appears to be related to an urban environment have worse prognosis. Alternative strategies targeting dysregulated cytokine balance could be considered for these patients at high risk of relapse.
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Affiliation(s)
- Marion Cremoni
- Service de Néphrologie-Dialyse-Transplantation, CHU de Nice, Université Côte d'Azur, Nice, France.,Unité de Recherche Clinique de la Côte d'Azur (UR2CA), Université Côte d'Azur, Nice, France
| | - Vesna Brglez
- Unité de Recherche Clinique de la Côte d'Azur (UR2CA), Université Côte d'Azur, Nice, France.,Centre de Référence Maladies Rares Syndrome Néphrotique Idiopathique, CHU de Nice, Université Côte d'Azur, Nice, France
| | - Sandra Perez
- UMR ESPACE 7300 CNRS, Université Côte d'Azur, Nice, France
| | | | - Kévin Zorzi
- Unité de Recherche Clinique de la Côte d'Azur (UR2CA), Université Côte d'Azur, Nice, France.,Centre de Référence Maladies Rares Syndrome Néphrotique Idiopathique, CHU de Nice, Université Côte d'Azur, Nice, France
| | - Marine Andreani
- Service de Néphrologie-Dialyse-Transplantation, CHU de Nice, Université Côte d'Azur, Nice, France
| | - Alexandre Gérard
- Service de Néphrologie-Dialyse-Transplantation, CHU de Nice, Université Côte d'Azur, Nice, France
| | - Sonia Boyer-Suavet
- Unité de Recherche Clinique de la Côte d'Azur (UR2CA), Université Côte d'Azur, Nice, France.,Centre de Référence Maladies Rares Syndrome Néphrotique Idiopathique, CHU de Nice, Université Côte d'Azur, Nice, France
| | - Caroline Ruetsch
- Laboratoire d'Immunologie, CHU de Nice, Université Côte d'Azur, Nice, France
| | - Sylvia Benzaken
- Laboratoire d'Immunologie, CHU de Nice, Université Côte d'Azur, Nice, France
| | - Vincent Esnault
- Service de Néphrologie-Dialyse-Transplantation, CHU de Nice, Université Côte d'Azur, Nice, France
| | - Barbara Seitz-Polski
- Service de Néphrologie-Dialyse-Transplantation, CHU de Nice, Université Côte d'Azur, Nice, France.,Unité de Recherche Clinique de la Côte d'Azur (UR2CA), Université Côte d'Azur, Nice, France.,Centre de Référence Maladies Rares Syndrome Néphrotique Idiopathique, CHU de Nice, Université Côte d'Azur, Nice, France.,Laboratoire d'Immunologie, CHU de Nice, Université Côte d'Azur, Nice, France
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18
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Dittrich D, Maskalan M, Kastelan Z, Palenkic H, Grubic Z. The role of HLA in Balkan endemic nephropathy. Gene 2020; 767:145179. [PMID: 33002571 DOI: 10.1016/j.gene.2020.145179] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/18/2020] [Accepted: 09/23/2020] [Indexed: 11/16/2022]
Abstract
Balkan endemic nephropathy (BEN), a progressive chronic tubulointerstitial disease, occurs in the endemic focus of Croatia in a population of about 10,000 inhabitants. One of its most peculiar characteristics is a strong association with upper tract urothelial carcinoma (UTUC). Despite a high number of studies, currently there are insufficient data about the association of BEN and HLA genes. The aim of this study was to investigate the polymorphism of HLA-A, -B, and -DRB1 alleles and haplotypes among BEN patients and to determine whether an association between HLA and BEN exists. In this study, we investigated HLA-A, -B, and -DRB1 alleles and haplotypes in a population of patients with BEN (N = 111) and matched healthy controls (N = 190). All individuals were tested by PCR-SSO and PCR-SSP methods to assess the possible contribution of HLA alleles and haplotypes to the development of/protection from BEN. Our results showed a positive association between the presence of HLA-B*35:02 and DRB1*04:02 alleles and BEN (P = 0.0179 and P = 0.0151, respectively) in contrast to the protective effect of HLA-A*01:01, B*27:05 and B*57:01 alleles (P = 0.0111, P = 0.0330 and P = 0.0318, respectively). Moreover, when BEN patients' HLA haplotypes were compared to controls, two haplotypes were associated with BEN susceptibility among Croatians (HLA-A*02:01~B*08:01~DRB1*03:01 and HLA-A*02:01~B*27:02~DRB1*16:01, P = 0.0064 and P = 0.0023, respectively), while haplotypes HLA-A*02:01~B*27:05~DRB1*01:01 and HLA-A*02:01~B*38:01~DRB1*13:01 each showed a possible protective effect (P = 0.0495). Our results point toward genetic susceptibility to BEN and observed differences in both susceptible/protective HLA profiles indicate the necessity of further studies in order to elucidate the pathogenesis of this disease.
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Affiliation(s)
- Damir Dittrich
- Department of Urology, General Hospital "Dr. Josip Bencevic", Slavonski Brod, Croatia
| | - Marija Maskalan
- Tissue Typing Centre, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Zeljko Kastelan
- Department of Urology, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Hrvoje Palenkic
- Department of Surgery, General Hospital "Dr. Josip Bencevic", Slavonski Brod, Croatia
| | - Zorana Grubic
- Tissue Typing Centre, University Hospital Centre Zagreb, Zagreb, Croatia.
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19
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Glomerular galactose-deficient IgA1 expression analysis in pediatric patients with glomerular diseases. Sci Rep 2020; 10:14026. [PMID: 32820208 PMCID: PMC7441388 DOI: 10.1038/s41598-020-71101-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 08/10/2020] [Indexed: 01/19/2023] Open
Abstract
Galactose-deficient IgA1 (Gd-IgA1) is important in the pathogenesis of IgA nephropathy (IgAN). A Gd-IgA1-specific monoclonal antibody (KM55) has revealed glomerular Gd-IgA1 deposition solely in patients with IgAN and IgA vasculitis with nephritis (IgAV-N). However, this specificity is controversial and has not been demonstrated in pediatric patients. Here, we conducted double-immunofluorescence staining of IgA and Gd-IgA1 in 60 pediatric patients with various glomerular diseases. We divided patients into four groups: (1) patients with IgAN and IgAV-N (n = 23); (2) patients with immunocomplex-mediated glomerulonephritis accompanied by IgA deposition, including lupus nephritis, membranoproliferative glomerulonephritis, and membranous nephropathy (n = 14); (3) patients with other glomerular diseases involving IgA deposition, including idiopathic nephrotic syndrome (INS), oligomeganephronia, Alport syndrome, dense deposit disease, and crescentic glomerulonephritis (n = 11); and (4) patients with IgA-negative diseases including INS, membranoproliferative glomerulonephritis, membranous nephropathy, oligomeganephronia, Alport syndrome, C3 glomerulonephritis, poststreptococcal acute glomerulonephritis, and hemolytic uremic syndrome (n = 12). KM55 staining revealed Gd-IgA1-positive findings in 23/23 patients in Group 1 and 13/14 patients in Group 2, but not in patients in Groups 3 or 4. Therefore, KM55 may detect incidental IgA deposition in pediatric patients. Gd-IgA1 may be involved in the pathogenesis of these immune-related diseases; alternatively, KM55 may recognize IgA-related immunocomplexes in a non-specific manner.
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20
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Single-nucleotide polymorphism rs4664308 in PLA2R1 gene is associated with the risk of idiopathic membranous nephropathy: a meta-analysis. Sci Rep 2020; 10:13119. [PMID: 32753608 PMCID: PMC7403323 DOI: 10.1038/s41598-020-70009-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Accepted: 07/22/2020] [Indexed: 01/11/2023] Open
Abstract
Although many studies investigated the associations between single-nucleotide polymorphisms (SNPs) in the M-type phospholipase A2 receptor-1 (PLA2R1) gene and susceptibility to idiopathic membranous nephropathy (IMN), some showed inconsistent results. Here, we conducted a meta-analysis examining the associations between PLA2R1 SNPs and IMN susceptibility after systematic searches in the PubMed and Web of Science databases. Our meta-analysis for rs4664308 A>G including 2,542 IMN patients and 4,396 controls in seven studies showed a significant association between the G allele and a lower risk of IMN, as determined using an allelic model (odds ratio, 0.45; 95% confidence interval [0.41–0.50]), an additive model (for GG vs. AA: 0.26; [0.21–0.33]; for AG vs. AA: 0.40; [0.36–0.45]), a dominant model (0.37; [0.34–0.42]) and a recessive model (0.38; [0.31–0.48]). Our meta-analysis also suggested associations between rs3828323, rs35771982, rs3749117 and rs3749119 and IMN susceptibility although high heterogeneities and/or publication biases were observed. We did not study in our meta-analysis, but other studies indicated that high-risk genotype combinations of rs2187668 in the human leucocyte antigen-DQ a-chain 1 gene and rs4664308 in the PLA2R1 gene had even stronger associations and could affect the formation of anti-PLA2R1 antibodies, suggesting these SNPs could be novel therapeutic targets.
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Abstract
Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by multiple system involvement and positive serum autoantibodies. Lupus nephritis (LN) is the most common and serious complication of SLE, and it is the main cause of death in patients with SLE. Abnormalities in the immune system lead to LN and involve a variety of cells (T cells, B cells, macrophages, NK cells, etc.), cytokines (interleukin, tumor necrosis factor α, etc.) and their related pathways. Previous studies have shown that the interactions of genetic, epigenetic and environmental factors contribute to the pathogenesis and development of LN. In recent years, one genome-wide association study (GWAS) and a number of gene association studies have explored the susceptibility genes of LN, including immunization-, inflammation-, adhesion- and other pathway-related genes. These genes participate in or suggest the pathogenesis and progression of LN. In this review, we summarize the genetic susceptibility of LN and discuss the possible mechanism underlying the susceptibility genes of LN.
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22
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The genetic architecture of membranous nephropathy and its potential to improve non-invasive diagnosis. Nat Commun 2020; 11:1600. [PMID: 32231244 PMCID: PMC7105485 DOI: 10.1038/s41467-020-15383-w] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 03/03/2020] [Indexed: 02/06/2023] Open
Abstract
Membranous Nephropathy (MN) is a rare autoimmune cause of kidney failure. Here we report a genome-wide association study (GWAS) for primary MN in 3,782 cases and 9,038 controls of East Asian and European ancestries. We discover two previously unreported loci, NFKB1 (rs230540, OR = 1.25, P = 3.4 × 10−12) and IRF4 (rs9405192, OR = 1.29, P = 1.4 × 10−14), fine-map the PLA2R1 locus (rs17831251, OR = 2.25, P = 4.7 × 10−103) and report ancestry-specific effects of three classical HLA alleles: DRB1*1501 in East Asians (OR = 3.81, P = 2.0 × 10−49), DQA1*0501 in Europeans (OR = 2.88, P = 5.7 × 10−93), and DRB1*0301 in both ethnicities (OR = 3.50, P = 9.2 × 10−23 and OR = 3.39, P = 5.2 × 10−82, respectively). GWAS loci explain 32% of disease risk in East Asians and 25% in Europeans, and correctly re-classify 20–37% of the cases in validation cohorts that are antibody-negative by the serum anti-PLA2R ELISA diagnostic test. Our findings highlight an unusual genetic architecture of MN, with four loci and their interactions accounting for nearly one-third of the disease risk. Membranous nephropathy (MN) is a rare autoimmune disease of podocyte-directed antibodies, such as anti-phospholipase A2 receptor. Here, the authors report a genome-wide association study for MN and identify two previously unreported loci encompassing the NFKB1 and IRF4 genes and additional ancestry-specific effects.
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23
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Epidemiology research to foster improvement in chronic kidney disease care. Kidney Int 2020; 97:477-486. [DOI: 10.1016/j.kint.2019.11.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 11/12/2019] [Accepted: 11/15/2019] [Indexed: 11/24/2022]
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24
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Lu W, Gong S, Li J, Wang Y. Clinicopathological features and prognosis in patients with idiopathic membranous nephropathy with hypertension. Exp Ther Med 2020; 19:2615-2621. [PMID: 32256741 PMCID: PMC7086205 DOI: 10.3892/etm.2020.8506] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 11/06/2019] [Indexed: 12/30/2022] Open
Abstract
The present study analyzed the clinicopathological features and prognosis in patients with idiopathic membranous nephropathy (IMN) with hypertension. In the hypertension group, significant differences were found in the age, hypertension history, systolic blood pressure, diastolic blood pressure (DBP), mean arterial pressure, albumin, serum creatinine, low-density lipoprotein, 24 h urine protein levels, calculated estimated glomerular filtration rate (e-GFR), glomerular sclerosis, segmental sclerosis, ischemic sclerosis, interstitial fibrosis, tubular atrophy and vascular lesion compared with the non-hypertension group (P<0.05). The average follow-up time was 35.70 months (5.10-103.77 months). In total, 54 patients reported a 50% decline in e-GFR, eight patients reported progression of disease to end-stage renal disease (ESRD) and nine cases of mortality were reported. Survival analysis results suggested that patients with hypertension had a lower cumulative renal survival rate than those without hypertension (P=0.034). Multivariate Cox hazards regression analysis results suggested that DBP [hazard ratio (H), 5.160; CI, 0.865-0.989; P=0.023], age (H, 4.839; CI, 1.008-1.142; P=0.028), sex (H, 5.680; CI, 0.031-0.714; P=0.017), serum creatinine (H, 20.920; CI, 1.035-1.089; P<0.001), uric acid (H, 4.783; CI, 0.982-0.0.999; P=0.029), 24 h urine protein (H, 6.318; CI, 1.079-1.850; P=0.012), e-GFR (H, 4.008; CI, 1.001-1.062; P=0.045) and glomerular sclerosis (H, 8.722; CI, 1.860-21.559; P=0.003), segmental sclerosis (H, 7.737; CI, 7.770-13.219; P=0.005), percentage of ischemic sclerosis (H, 4.729; CI, 1.444-11.945; P=0.030), crescents (H, 5.938; CI, 0.003-0.526; P=0.015), interstitial fibrosis and tubular atrophy (H, 8.128; CI, 0.005-1.052; P=0.043), and vascular lesion (H, 4.049; CI, 1.030-9.766; P=0.044) were risk factors for the development of IMN into ESRD. The results suggested that DBP may be an independent risk factor for the development of IMN with hypertension.
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Affiliation(s)
- Wanjun Lu
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Shuhao Gong
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Juan Li
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Ying Wang
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
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25
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Cravedi P, Jarque M, Angeletti A, Favà À, Cantarelli C, Bestard O. Immune-Monitoring Disease Activity in Primary Membranous Nephropathy. Front Med (Lausanne) 2019; 6:241. [PMID: 31788474 PMCID: PMC6856075 DOI: 10.3389/fmed.2019.00241] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 10/14/2019] [Indexed: 01/03/2023] Open
Abstract
Primary membranous nephropathy (MN) is a glomerular disease mediated by autoreactive antibodies, being the main cause of nephrotic syndrome among adult patients. While the pathogenesis of MN is still controversial, the detection of autoantibodies against two specific glomerular antigens, phospholipase A2 receptor (PLA2R) and thrombospondin type 1 domain containing 7A (THSD7A), together with the beneficial effect of therapies targeting B cells, have highlighted the main role of autoreactive B cells driving this renal disease. In fact, the detection of PLA2R-specific IgG4 antibodies has resulted in a paradigm shift regarding the diagnosis as well as a better prediction of the progression and recurrence of primary MN. Nevertheless, some patients do not show remission of the nephrotic syndrome or do rapidly recur after immunosuppression withdrawal, regardless the absence of detectable anti-PLA2R antibodies, thus highlighting the need of other immune biomarkers for MN risk-stratification. Notably, the exclusive evaluation of circulating antibodies may significantly underestimate the magnitude of the global humoral memory immune response since it may exclude the role of antigen-specific memory B cells. Therefore, the assessment of PLA2R-specific B-cell immune responses using novel technologies in a functional manner may provide novel insight on the pathogenic mechanisms of B cells triggering MN as well as refine current immune-risk stratification solely based on circulating autoantibodies.
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Affiliation(s)
- Paolo Cravedi
- Renal Division, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Marta Jarque
- Experimental Nephrology Laboratory, Biomedical Research Institute of Bellvitge (IDIBELL), Barcelona, Spain
| | - Andrea Angeletti
- Nephrology, Dialysis and Renal Transplant Unit, Department of Experimental Diagnostic and Specialty Medicine (DIMES), St. Orsola Hospital, University of Bologna, Bologna, Italy
| | - Àlex Favà
- Experimental Nephrology Laboratory, Biomedical Research Institute of Bellvitge (IDIBELL), Barcelona, Spain
| | - Chiara Cantarelli
- UO Nefrologia, Dipartimento di Medicina e Chirurgia, Azienda Ospedaliero-Universitaria Parma, Parma, Italy
| | - Oriol Bestard
- Experimental Nephrology Laboratory, Biomedical Research Institute of Bellvitge (IDIBELL), Barcelona, Spain.,Kidney Transplant Unit, Nephrology Department, Bellvitge University Hospital, Barcelona University, Biomedical Research Institute of Bellvitge (IDIBELL), Barcelona, Spain
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26
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Song K, Liu L, Zhang X, Chen X. An update on genetic susceptibility in lupus nephritis. Clin Immunol 2019; 210:108272. [PMID: 31683055 DOI: 10.1016/j.clim.2019.108272] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 09/11/2019] [Accepted: 10/09/2019] [Indexed: 12/17/2022]
Abstract
Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by multiple system involvement and positive serum autoantibodies. Lupus nephritis (LN) is the most common and serious complication of SLE, and it is the main cause of death in patients with SLE. Abnormalities in the immune system lead to LN and involve a variety of cells (T cells, B cells, macrophages, NK cells, etc.), cytokines (interleukin, tumor necrosis factor α, etc.) and their related pathways. Previous studies have shown that the interactions of genetic, epigenetic and environmental factors contribute to the pathogenesis and development of LN. In recent years, one genome-wide association study (GWAS) and a number of gene association studies have explored the susceptibility genes of LN, including immunization-, inflammation-, adhesion- and other pathway-related genes. These genes participate in or suggest the pathogenesis and progression of LN. In this review, we summarize the genetic susceptibility of LN and discuss the possible mechanism underlying the susceptibility genes of LN.
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Affiliation(s)
- Kangkang Song
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Laboratory of Kidney Diseases, 28 Fuxing Road, Beijing, China
| | - Lu Liu
- Institute of Dermatology and Department of Dermatology at No.1 Hospital, Anhui Medical University, Key Laboratory of Dermatology, Ministry of Education (Anhui Medical University), Hefei, Anhui, China
| | - Xuejun Zhang
- Institute of Dermatology and Department of Dermatology at No.1 Hospital, Anhui Medical University, Key Laboratory of Dermatology, Ministry of Education (Anhui Medical University), Hefei, Anhui, China; Institute of Dermatology and Department of Dermatology, Huashan Hospital of Fudan University, Shanghai, China
| | - Xiangmei Chen
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Laboratory of Kidney Diseases, 28 Fuxing Road, Beijing, China.
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27
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Ronco P, Debiec H. Molecular Pathogenesis of Membranous Nephropathy. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2019; 15:287-313. [PMID: 31622560 DOI: 10.1146/annurev-pathol-020117-043811] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Membranous nephropathy is a noninflammatory autoimmune disease of the kidney glomerulus, characterized by the formation of immune deposits, complement-mediated proteinuria, and risk of renal failure. Considerable advances in understanding the molecular pathogenesis have occurred with the identification of several antigens [neutral endopeptidase, phospholipase A2 receptor (PLA2R), thrombospondin domain-containing 7A (THSD7A)] in cases arising from the neonatal period to adulthood and the characterization of antibody-binding domains (that is, epitopes). Immunization against PLA2R occurs in 70% to 80% of adult cases. The development of highly specific and sensitive assays of circulating antibodies has induced a paradigm shift in diagnosis and treatment monitoring. In addition, several interacting loci in HLA-DQ, HLA-DR, and PLA2R1, as well as classical human leukocyte antigen (HLA)-D alleles have been identified as being risk factors, depending on a patient's ethnicity. Additionally, mechanisms of antibody pathogenicity and pathways of complement activation are now better understood. Further research is mandatory for designing new therapeutic strategies, including the identifying triggering events, the molecular bases of remission and progression, and the T cell epitopes involved.
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Affiliation(s)
- Pierre Ronco
- Rare and Common Kidney Diseases: From Molecular Mechanisms to Personalized Medicine Unit, INSERM UMRS 1155, Sorbonne Université, 75020 Paris, France;
| | - Hanna Debiec
- Rare and Common Kidney Diseases: From Molecular Mechanisms to Personalized Medicine Unit, INSERM UMRS 1155, Sorbonne Université, 75020 Paris, France;
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Raveane A, Aneli S, Montinaro F, Athanasiadis G, Barlera S, Birolo G, Boncoraglio G, Di Blasio AM, Di Gaetano C, Pagani L, Parolo S, Paschou P, Piazza A, Stamatoyannopoulos G, Angius A, Brucato N, Cucca F, Hellenthal G, Mulas A, Peyret-Guzzon M, Zoledziewska M, Baali A, Bycroft C, Cherkaoui M, Chiaroni J, Di Cristofaro J, Dina C, Dugoujon JM, Galan P, Giemza J, Kivisild T, Mazieres S, Melhaoui M, Metspalu M, Myers S, Pereira L, Ricaut FX, Brisighelli F, Cardinali I, Grugni V, Lancioni H, Pascali VL, Torroni A, Semino O, Matullo G, Achilli A, Olivieri A, Capelli C. Population structure of modern-day Italians reveals patterns of ancient and archaic ancestries in Southern Europe. SCIENCE ADVANCES 2019; 5:eaaw3492. [PMID: 31517044 PMCID: PMC6726452 DOI: 10.1126/sciadv.aaw3492] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 04/10/2019] [Accepted: 08/06/2019] [Indexed: 05/10/2023]
Abstract
European populations display low genetic differentiation as the result of long-term blending of their ancient founding ancestries. However, it is unclear how the combination of ancient ancestries related to early foragers, Neolithic farmers, and Bronze Age nomadic pastoralists can explain the distribution of genetic variation across Europe. Populations in natural crossroads like the Italian peninsula are expected to recapitulate the continental diversity, but have been systematically understudied. Here, we characterize the ancestry profiles of Italian populations using a genome-wide dataset representative of modern and ancient samples from across Italy, Europe, and the rest of the world. Italian genomes capture several ancient signatures, including a non-steppe contribution derived ultimately from the Caucasus. Differences in ancestry composition, as the result of migration and admixture, have generated in Italy the largest degree of population structure detected so far in the continent, as well as shaping the amount of Neanderthal DNA in modern-day populations.
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Affiliation(s)
- A. Raveane
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
- Department of Zoology, University of Oxford, Oxford, UK
- Corresponding author. (A.R.); (S.A.); (F.M.); (C.C.)
| | - S. Aneli
- Department of Zoology, University of Oxford, Oxford, UK
- Department of Medical Sciences, University of Turin, Turin, Italy
- IIGM (Italian Institute for Genomic Medicine), Turin, Italy
- Corresponding author. (A.R.); (S.A.); (F.M.); (C.C.)
| | - F. Montinaro
- Department of Zoology, University of Oxford, Oxford, UK
- Estonian Biocentre, Institute of Genomics, University of Tartu, Tartu, Estonia
- Corresponding author. (A.R.); (S.A.); (F.M.); (C.C.)
| | - G. Athanasiadis
- Bioinformatics Research Centre, Aarhus University, Aarhus, Denmark
| | - S. Barlera
- Department of Cardiovascular Research, Istituto di Ricovero e Cura a Carattere Scientifico–Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy
| | - G. Birolo
- Department of Medical Sciences, University of Turin, Turin, Italy
- IIGM (Italian Institute for Genomic Medicine), Turin, Italy
| | - G. Boncoraglio
- Department of Cerebrovascular Diseases, IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
- PhD Program in Neuroscience, University Milano-Bicocca, Monza, Italy
| | - A. M. Di Blasio
- Istituto Auxologico Italiano, IRCCS, Centro di Ricerche e Tecnologie Biomediche, Milano, Italy
| | - C. Di Gaetano
- Department of Medical Sciences, University of Turin, Turin, Italy
- IIGM (Italian Institute for Genomic Medicine), Turin, Italy
| | - L. Pagani
- Estonian Biocentre, Institute of Genomics, University of Tartu, Tartu, Estonia
- APE lab, Department of Biology, University of Padua, Padua, Italy
| | - S. Parolo
- Computational Biology Unit, Institute of Molecular Genetics, National Research Council, Pavia, Italy
| | - P. Paschou
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - A. Piazza
- Department of Medical Sciences, University of Turin, Turin, Italy
- Academy of Sciences, Turin, Italy
| | - G. Stamatoyannopoulos
- Department of Medicine and Genome Sciences, University of Washington, Seattle, WA, USA
| | - A. Angius
- Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche (CNR), Monserrato, Cagliari, Italy
| | - N. Brucato
- Evolutionary Medicine Group, Laboratoire d’Anthropologie Moléculaire et Imagerie de Synthèse, Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse, France
| | - F. Cucca
- Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche (CNR), Monserrato, Cagliari, Italy
| | - G. Hellenthal
- University College London Genetics Institute (UGI), University College London, London, UK
| | - A. Mulas
- Istituto di Ricerca Genetica e Biomedica (IRGB), CNR, Lanusei, Italy
| | - M. Peyret-Guzzon
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - M. Zoledziewska
- Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche (CNR), Monserrato, Cagliari, Italy
| | - A. Baali
- Faculté des Sciences Semlalia de Marrakech (FSSM), Université Cadi Ayyad, Marrakech, Morocco
| | - C. Bycroft
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - M. Cherkaoui
- Faculté des Sciences Semlalia de Marrakech (FSSM), Université Cadi Ayyad, Marrakech, Morocco
| | - J. Chiaroni
- Aix Marseille Univ, CNRS, EFS, ADES, Marseille, France
- Etablissement Français du Sang PACA Corse, Biologie des Groupes Sanguins, Marseille, France
| | - J. Di Cristofaro
- Aix Marseille Univ, CNRS, EFS, ADES, Marseille, France
- Etablissement Français du Sang PACA Corse, Biologie des Groupes Sanguins, Marseille, France
| | - C. Dina
- l’institut du thorax, INSERM, CNRS, University of Nantes, Nantes, France
| | - J. M. Dugoujon
- Evolutionary Medicine Group, Laboratoire d’Anthropologie Moléculaire et Imagerie de Synthèse, Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse, France
| | - P. Galan
- Equipe de Recherche en Epidémiologie Nutritionnelle (EREN), Centre de Recherche en Epidémiologie et Statistiques, Université Paris 13/Inserm U1153/Inra U1125/ Cnam, COMUE Sorbonne Paris Cité, F-93017 Bobigny, France
| | - J. Giemza
- l’institut du thorax, INSERM, CNRS, University of Nantes, Nantes, France
| | - T. Kivisild
- Estonian Biocentre, Institute of Genomics, University of Tartu, Tartu, Estonia
- Department of Human Genetics, KU Leuven, Herestraat 49, box 604, Leuven 3000, Belgium
| | - S. Mazieres
- Aix Marseille Univ, CNRS, EFS, ADES, Marseille, France
| | - M. Melhaoui
- Faculté des Sciences, Université Mohammed Premier, Oujda, Morocco
| | - M. Metspalu
- Estonian Biocentre, Institute of Genomics, University of Tartu, Tartu, Estonia
| | - S. Myers
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - L. Pereira
- i3S–Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP–Instituto de Patologia e Imunologia Molecular, Universidade do Porto, Porto, Portugal
| | - F. X. Ricaut
- Evolutionary Medicine Group, Laboratoire d’Anthropologie Moléculaire et Imagerie de Synthèse, Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse, France
| | - F. Brisighelli
- Section of Legal Medicine, Institute of Public Health, Catholic University of the Sacred Heart, Rome, Italy
| | - I. Cardinali
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - V. Grugni
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - H. Lancioni
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - V. L. Pascali
- Section of Legal Medicine, Institute of Public Health, Catholic University of the Sacred Heart, Rome, Italy
| | - A. Torroni
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - O. Semino
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - G. Matullo
- Department of Medical Sciences, University of Turin, Turin, Italy
- IIGM (Italian Institute for Genomic Medicine), Turin, Italy
| | - A. Achilli
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - A. Olivieri
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - C. Capelli
- Department of Zoology, University of Oxford, Oxford, UK
- Corresponding author. (A.R.); (S.A.); (F.M.); (C.C.)
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van de Logt AE, Fresquet M, Wetzels JF, Brenchley P. The anti-PLA2R antibody in membranous nephropathy: what we know and what remains a decade after its discovery. Kidney Int 2019; 96:1292-1302. [PMID: 31611068 DOI: 10.1016/j.kint.2019.07.014] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 06/08/2019] [Accepted: 07/05/2019] [Indexed: 12/21/2022]
Abstract
The discovery in 2009 of the M-type phospholipase A2 receptor (PLA2R) as the primary target in membranous nephropathy (MN) greatly advanced basic and clinical research. Primary MN is now considered a renal-limited autoimmune disease, with antibodies against PLA2R (aPLA2Rab) identified in 70-80 % of patients of various ethnic groups. Although the use of aPLA2Rab as a diagnostic and prognostic biomarker is now widely accepted, many questions related to the development of the auto-immune response, the role of IgG subclasses and antigenic epitopes, and the pathways to podocyte injury remain unresolved. PLA2R-associated MN most likely develops governed by factors such as genetic susceptibility, loss of tolerance, alterations in antigen expression with a role for environmental factors like air pollution, smoking, and infections. More detailed knowledge of genetic factors, the relevant B- and T-cell epitopes, and the mechanisms of podocyte injury is needed to identify patients at risk for disease progression and to develop optimized, targeted treatment strategies. In this review we highlight unresolved issues, addressing initiation of antibody formation, the timeline of antibody production, the role of IgG subclass, and the pathogenicity of the antibodies in concert with complement to produce glomerular pathology and proteinuria.
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Affiliation(s)
- Anne-Els van de Logt
- Department of Nephrology, Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, The Netherlands.
| | - Maryline Fresquet
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine and Health, University of Manchester, UK
| | - Jack F Wetzels
- Department of Nephrology, Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, The Netherlands
| | - Paul Brenchley
- Institute of Cardiovascular Sciences, Faculty of Medicine, Biology and Health, University of Manchester, Manchester, UK
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Abstract
PURPOSE OF REVIEW Despite major advances in since the discovery of the phospholipase A2 receptor (PLA2R) as the major autoantigen on podocytes in primary membranous nephropathy, there are still several unanswered questions as highlighted here. RECENT FINDINGS A substantial body of literature, included in more than 680 articles since 2009, has documented genetic susceptibility to primary membranous nephropathy involving PLA2R1 and class II MHC alleles, the clinical value of anti-PLA2R assays, the significance of epitope spreading of the anti-PLA2R response, discovery of thrombospondin type I domain-containing 7A (THSD7A) as a minor antigen in primary membranous nephropathy, and the ability to transfer disease into mice by infusion of anti-THSD7A sera. However, the normal physiology and pathophysiology of PLA2R and THSD7A in podocytes is still unknown and the genetic influence on disease susceptibility is unexplained. We still do not know what causes loss of self-tolerance to PLA2R and THSD7A or how the autoantibodies, which are predominantly of the IgG4 subclass, cause podocyte injury and proteinuria. Complement deposits are prominent in membranous nephropathy but we are still uncertain how the complement system is activated and whether or not it plays a role in podocyte damage. Notwithstanding the advances over the past decade, our treatments have not changed substantially. SUMMARY This review identifies opportunities to extend the advances that have been made to better understand the immunopathogenesis and genetic basis of primary membranous nephropathy and apply the knowledge to design more specific therapies.
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Liu D, Zhang J, Shi Y, Liu Z. Gene polymorphism and risk of idiopathic membranous nephropathy. Life Sci 2019; 229:124-131. [DOI: 10.1016/j.lfs.2019.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 04/30/2019] [Accepted: 05/06/2019] [Indexed: 01/09/2023]
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Dufek S, Cheshire C, Levine AP, Trompeter RS, Issler N, Stubbs M, Mozere M, Gupta S, Klootwijk E, Patel V, Hothi D, Waters A, Webb H, Tullus K, Jenkins L, Godinho L, Levtchenko E, Wetzels J, Knoers N, Teeninga N, Nauta J, Shalaby M, Eldesoky S, Kari JA, Thalgahagoda S, Ranawaka R, Abeyagunawardena A, Adeyemo A, Kristiansen M, Gbadegesin R, Webb NJ, Gale DP, Stanescu HC, Kleta R, Bockenhauer D. Genetic Identification of Two Novel Loci Associated with Steroid-Sensitive Nephrotic Syndrome. J Am Soc Nephrol 2019; 30:1375-1384. [PMID: 31263063 DOI: 10.1681/asn.2018101054] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Accepted: 04/22/2019] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Steroid-sensitive nephrotic syndrome (SSNS), the most common form of nephrotic syndrome in childhood, is considered an autoimmune disease with an established classic HLA association. However, the precise etiology of the disease is unclear. In other autoimmune diseases, the identification of loci outside the classic HLA region by genome-wide association studies (GWAS) has provided critical insights into disease pathogenesis. Previously conducted GWAS of SSNS have not identified non-HLA loci achieving genome-wide significance. METHODS In an attempt to identify additional loci associated with SSNS, we conducted a GWAS of a large cohort of European ancestry comprising 422 ethnically homogeneous pediatric patients and 5642 ethnically matched controls. RESULTS The GWAS found three loci that achieved genome-wide significance, which explain approximately 14% of the genetic risk for SSNS. It confirmed the previously reported association with the HLA-DR/DQ region (lead single-nucleotide polymorphism [SNP] rs9273542, P=1.59×10-43; odds ratio [OR], 3.39; 95% confidence interval [95% CI], 2.86 to 4.03) and identified two additional loci outside the HLA region on chromosomes 4q13.3 and 6q22.1. The latter contains the calcium homeostasis modulator family member 6 gene CALHM6 (previously called FAM26F). CALHM6 is implicated in immune response modulation; the lead SNP (rs2637678, P=1.27×10-17; OR, 0.51; 95% CI, 0.44 to 0.60) exhibits strong expression quantitative trait loci effects, the risk allele being associated with lower lymphocytic expression of CALHM6. CONCLUSIONS Because CALHM6 is implicated in regulating the immune response to infection, this may provide an explanation for the typical triggering of SSNS onset by infections. Our results suggest that a genetically conferred risk of immune dysregulation may be a key component in the pathogenesis of SSNS.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Vaksha Patel
- Great Ormond Street Hospital, London, United Kingdom
| | - Daljit Hothi
- Great Ormond Street Hospital, London, United Kingdom
| | - Aoife Waters
- Great Ormond Street Hospital, London, United Kingdom
| | - Hazel Webb
- Great Ormond Street Hospital, London, United Kingdom
| | - Kjell Tullus
- Great Ormond Street Hospital, London, United Kingdom
| | - Lucy Jenkins
- Great Ormond Street Hospital, London, United Kingdom
| | | | - Elena Levtchenko
- University Hospitals Leuven and University of Leuven, Leuven, Belgium
| | - Jack Wetzels
- Nephrology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Nine Knoers
- Department of Genetics, UMC Groningen, Groningen, The Netherlands
| | - Nynke Teeninga
- Department of Pediatric Nephrology, Erasmus University Medical Centre-Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Jeroen Nauta
- Department of Pediatric Nephrology, Erasmus University Medical Centre-Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Mohamed Shalaby
- Pediatric Nephrology Center of Excellence, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia
| | - Sherif Eldesoky
- Pediatric Nephrology Center of Excellence, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia
| | - Jameela A Kari
- Pediatric Nephrology Center of Excellence, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia
| | | | - Randula Ranawaka
- Department of Paediatrics, University of Peradeniya, Peradeniya, Sri Lanka
| | | | | | - Mark Kristiansen
- University College London Genomics, Institute of Child Health, University College London, London, United Kingdom
| | - Rasheed Gbadegesin
- Department of Pediatrics, Duke University School of Medicine, Durham, North Carolina; and
| | - Nicholas J Webb
- Department of Paediatric Nephrology and.,NIHR Manchester Clinical Research Facility, Manchester Academic Health Science Centre, Royal Manchester Children's Hospital, Manchester, United Kingdom
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Kamyshova ES, Bobkova IN, Gorelova IA, Каkhsurueva PA, Filatova EE. Genetic determinants of the development and course of membranous nephropathy. TERAPEVT ARKH 2019; 90:105-111. [PMID: 30701913 DOI: 10.26442/terarkh2018906105-111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Membranous nephropathy (MN) is one of the most common causes of nephrotic syndrome in adults and is classified as either primary (idiopatic) or secondary MN according to underlying etiology (the later result from some known disease such as systemic autoimmune diseases, infections, malignancies, drugs, etc). In recent years, phospholipase A2 receptor 1 (PLA2R) and thrombospondin type-1 domain-containing 7A (THSD7A) were identified as two major podocytic antigens involved in the pathogenesis of idiopatic MN (IMN). And the discovery of circulating antibodies specific for these target antigens has transformed the diagnostic workup and significally improved management of IMN. However why do such antibodies develop is not conclusively established. The role of underlying genetic factors is discussed. The review presents the results of recent studies, that have shown significant associations of specific genetic factors (particularly human leucocyte antigen class II and PLA2R1 genes) with IMN.
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Affiliation(s)
- E S Kamyshova
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia (Sechenov University), Moscow, Russia
| | - I N Bobkova
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia (Sechenov University), Moscow, Russia
| | - I A Gorelova
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia (Sechenov University), Moscow, Russia
| | - P A Каkhsurueva
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia (Sechenov University), Moscow, Russia
| | - E E Filatova
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia (Sechenov University), Moscow, Russia
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Fox CS. Using Human Genetics to Drive Drug Discovery: A Perspective. Am J Kidney Dis 2019; 74:111-119. [PMID: 30898364 DOI: 10.1053/j.ajkd.2018.12.045] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 12/24/2018] [Indexed: 12/11/2022]
Abstract
The probability of success of developing medicines to treat human disease can be improved by leveraging human genetics. Different types of genetic data and techniques, including genome-wide association, whole-exome sequencing, and whole-genome sequencing, can be used to gain insight into human disease. Layering different types of genetic evidence from Mendelian disease, coding variants, and common variation can bolster support for a genetic target. Human knockouts offer the potential to perform reverse genetic screens in humans to identify physiologically relevant targets. Other components of a good genetic target include protective loss-of-function mutations, some degree of known biology, tractability, and a clean on-target safety profile. In addition to using human genetics to inspire new drug programs, phenome-wide association studies can be used to identify alternative indications or repurposing opportunities. This information can be combined into a 5-step approach for selecting a genetic target for validation, which is presented in detail in this review. Finally, current challenges in leveraging human genetics are highlighted, including the difficulties translating certain types of genetic data, relatively small number of bona fide disease-associated coding rare variants, and current sample sizes of large well-curated biobanks linked to comprehensive genetic information.
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Zhou G, Zhang X, Wang W, Zhang W, Wang H, Xin G. Both Peripheral Blood and Urinary miR-195-5p, miR-192-3p, miR-328-5p and Their Target Genes PPM1A, RAB1A and BRSK1 May Be Potential Biomarkers for Membranous Nephropathy. Med Sci Monit 2019; 25:1903-1916. [PMID: 30865617 PMCID: PMC6427931 DOI: 10.12659/msm.913057] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background To identify noninvasive diagnostic biomarkers for membranous nephropathy (MN). Material/Methods The mRNA microarray datasets GSE73953 using peripheral blood mononuclear cells (PBMCs) of 8 membranous nephropathy patients and 2 control patients; and microRNAs (miRNA) microarray dataset GSE64306 using urine sediments of 4 membranous nephropathy patients and 6 control patients were downloaded from the Gene Expression Omnibus database. The differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) were respectively identified from PBMCs and urine sediments of membranous nephropathy patients, followed with functional enrichment analysis, protein-protein interaction (PPI) analysis, and miRNA-target gene analysis. Finally, the DEGs and the target genes of DEMs were overlapped to obtain crucial miRNA-mRNA interaction pairs for membranous nephropathy. Results A total of 1246 DEGs were identified from PBMCs samples, among them upregulated CCL5 was found to be involved in the chemokine signaling pathway, and BAX was found to be apoptosis related; while downregulated PPM1A and CDK1 were associated with the MAPK signaling pathway and the p53 signaling pathway, respectively. The hub role of CDK1 (degree=18) and CCL5 (degree=12) were confirmed after protein-protein interaction network analysis in which CKD1 could interact with RAB1A. A total of 28 DEMs were identified in urine sediments. The 276 target genes of DEMs were involved in cell cycle arrest (PPM1A) and intracellular signal transduction (BRSK1). Thirteen genes were shared between the DEGs in PMBCs and the target genes of DEMs in urine sediments, but only hsa-miR-192-3p-RAB1A, hsa-miR-195-5p-PPM1A, and hsa-miR-328-5p-BRSK1 were negatively related in their expression level. Conclusions Both peripheral blood and urinary miR-195-5p, miR-192-3p, miR-328-5p, and their target genes PPM1A, RAB1A, and BRSK1 may be potential biomarkers for membranous nephropathy by participating in inflammation and apoptosis.
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Affiliation(s)
- Guangyu Zhou
- Department of Nephrology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China (mainland)
| | - Xiaofei Zhang
- Department of Pediatrics, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China (mainland)
| | - Wanning Wang
- Department of Nephrology, The First Hospital of Jilin University, Changchun, Jilin, China (mainland)
| | - Wenlong Zhang
- Department of Hematology and Oncology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China (mainland)
| | - Huaying Wang
- Department of Nephrology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China (mainland)
| | - Guangda Xin
- Department of Nephrology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China (mainland)
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Lane BM, Cason R, Esezobor CI, Gbadegesin RA. Genetics of Childhood Steroid Sensitive Nephrotic Syndrome: An Update. Front Pediatr 2019; 7:8. [PMID: 30761277 PMCID: PMC6361778 DOI: 10.3389/fped.2019.00008] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 01/11/2019] [Indexed: 12/12/2022] Open
Abstract
Advances in genome science in the last 20 years have led to the discovery of over 50 single gene causes and genetic risk loci for steroid resistant nephrotic syndrome (SRNS). Despite these advances, the genetic architecture of childhood steroid sensitive nephrotic syndrome (SSNS) remains poorly understood due in large part to the varying clinical course of SSNS over time. Recent exome and genome wide association studies from well-defined cohorts of children with SSNS identified variants in multiple MHC class II molecules such as HLA-DQA1 and HLA-DQB1 as risk factors for SSNS, thus stressing the central role of adaptive immunity in the pathogenesis of SSNS. However, evidence suggests that unknown second hit risk loci outside of the MHC locus and environmental factors also make significant contributions to disease. In this review, we examine what is currently known about the genetics of SSNS, the implications of recent findings on our understanding of pathogenesis of SSNS, and how we can utilize these results and findings from future studies to improve the management of children with nephrotic syndrome.
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Affiliation(s)
- Brandon M Lane
- Division of Nephrology, Departments of Pediatrics, Duke University Medical Center, Durham, NC, United States.,Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC, United States
| | - Rachel Cason
- Division of Nephrology, Departments of Pediatrics, Duke University Medical Center, Durham, NC, United States
| | | | - Rasheed A Gbadegesin
- Division of Nephrology, Departments of Pediatrics, Duke University Medical Center, Durham, NC, United States.,Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC, United States
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Cañadas-Garre M, Anderson K, McGoldrick J, Maxwell AP, McKnight AJ. Genomic approaches in the search for molecular biomarkers in chronic kidney disease. J Transl Med 2018; 16:292. [PMID: 30359254 PMCID: PMC6203198 DOI: 10.1186/s12967-018-1664-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 10/14/2018] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Chronic kidney disease (CKD) is recognised as a global public health problem, more prevalent in older persons and associated with multiple co-morbidities. Diabetes mellitus and hypertension are common aetiologies for CKD, but IgA glomerulonephritis, membranous glomerulonephritis, lupus nephritis and autosomal dominant polycystic kidney disease are also common causes of CKD. MAIN BODY Conventional biomarkers for CKD involving the use of estimated glomerular filtration rate (eGFR) derived from four variables (serum creatinine, age, gender and ethnicity) are recommended by clinical guidelines for the evaluation, classification, and stratification of CKD. However, these clinical biomarkers present some limitations, especially for early stages of CKD, elderly individuals, extreme body mass index values (serum creatinine), or are influenced by inflammation, steroid treatment and thyroid dysfunction (serum cystatin C). There is therefore a need to identify additional non-invasive biomarkers that are useful in clinical practice to help improve CKD diagnosis, inform prognosis and guide therapeutic management. CONCLUSION CKD is a multifactorial disease with associated genetic and environmental risk factors. Hence, many studies have employed genetic, epigenetic and transcriptomic approaches to identify biomarkers for kidney disease. In this review, we have summarised the most important studies in humans investigating genomic biomarkers for CKD in the last decade. Several genes, including UMOD, SHROOM3 and ELMO1 have been strongly associated with renal diseases, and some of their traits, such as eGFR and serum creatinine. The role of epigenetic and transcriptomic biomarkers in CKD and related diseases is still unclear. The combination of multiple biomarkers into classifiers, including genomic, and/or epigenomic, may give a more complete picture of kidney diseases.
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Affiliation(s)
- M. Cañadas-Garre
- Epidemiology and Public Health Research Group, Centre for Public Health, Belfast City Hospital, Queen’s University of Belfast, c/o University Floor, Level A, Tower Block, Lisburn Road, Belfast, BT9 7AB Northern Ireland UK
| | - K. Anderson
- Epidemiology and Public Health Research Group, Centre for Public Health, Belfast City Hospital, Queen’s University of Belfast, c/o University Floor, Level A, Tower Block, Lisburn Road, Belfast, BT9 7AB Northern Ireland UK
| | - J. McGoldrick
- Epidemiology and Public Health Research Group, Centre for Public Health, Belfast City Hospital, Queen’s University of Belfast, c/o University Floor, Level A, Tower Block, Lisburn Road, Belfast, BT9 7AB Northern Ireland UK
| | - A. P. Maxwell
- Epidemiology and Public Health Research Group, Centre for Public Health, Belfast City Hospital, Queen’s University of Belfast, c/o University Floor, Level A, Tower Block, Lisburn Road, Belfast, BT9 7AB Northern Ireland UK
- Regional Nephrology Unit, Belfast City Hospital, Belfast, UK
| | - A. J. McKnight
- Epidemiology and Public Health Research Group, Centre for Public Health, Belfast City Hospital, Queen’s University of Belfast, c/o University Floor, Level A, Tower Block, Lisburn Road, Belfast, BT9 7AB Northern Ireland UK
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Latt KZ, Honda K, Thiri M, Hitomi Y, Omae Y, Sawai H, Kawai Y, Teraguchi S, Ueno K, Nagasaki M, Mabuchi A, Kaga H, Komatsuda A, Tokunaga K, Noiri E. Identification of a two-SNP PLA2R1 Haplotype and HLA-DRB1 Alleles as Primary Risk Associations in Idiopathic Membranous Nephropathy. Sci Rep 2018; 8:15576. [PMID: 30349113 PMCID: PMC6197221 DOI: 10.1038/s41598-018-33612-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 10/03/2018] [Indexed: 01/12/2023] Open
Abstract
The associations of single nucleotide polymorphisms (SNPs) in PLA2R1 and HLA-DQA1, as well as HLA-DRB1*15:01-DQB1*06:02 haplotype with idiopathic membranous nephropathy (IMN) is well known. However, the primary associations of these loci still need to be determined. We used Japanese-specific SNP genotyping array and imputation using 2,048 sequenced Japanese samples to fine-map PLA2R1 region in 98 patients and 413 controls. The most significant SNPs were replicated in a separate sample set of 130 patients and 288 controls. A two-SNP haplotype of intronic and missense SNPs showed the strongest association. The intronic SNP is strongly associated with PLA2R1 expression in the Genotype-Tissue Expression (GTEx) database, and the missense SNP is predicted to alter peptide binding with HLA-DRB1*15:01 by the Immune Epitope Database (IEDB). In HLA region, we performed relative predispositional effect (RPE) tests and identified additional risk alleles in both HLA-DRB1 and HLA-DQB1. We collapsed the risk alleles in each of HLA-DRB1 and HLA-DQB1 into single risk alleles. Reciprocal conditioning of these collapsed risk alleles showed more residual significance for HLA-DRB1 collapsed risk than HLA-DQB1 collapsed risk. These results indicate that changes in the expression levels of structurally different PLA2R protein confer risk for IMN in the presence of risk HLA-DRB1 alleles.
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Affiliation(s)
- Khun Zaw Latt
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kenjiro Honda
- Department of Nephrology and Endocrinology, The University of Tokyo Hospital, Tokyo, Japan
| | - Myo Thiri
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yuki Hitomi
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yosuke Omae
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiromi Sawai
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yosuke Kawai
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Shunsuke Teraguchi
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Kazuko Ueno
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Masao Nagasaki
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Akihiko Mabuchi
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hajime Kaga
- Department of Hematology, Nephrology, and Rheumatology, Graduate School of Medicine, Akita University, Akita, Japan
| | - Atsushi Komatsuda
- Department of Hematology, Nephrology, and Rheumatology, Graduate School of Medicine, Akita University, Akita, Japan
| | - Katsushi Tokunaga
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
| | - Eisei Noiri
- Department of Nephrology and Endocrinology, The University of Tokyo Hospital, Tokyo, Japan. .,Department of Hemodialysis and Apheresis, The University of Tokyo Hospital, Tokyo, Japan.
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Robson KJ, Ooi JD, Holdsworth SR, Rossjohn J, Kitching AR. HLA and kidney disease: from associations to mechanisms. Nat Rev Nephrol 2018; 14:636-655. [DOI: 10.1038/s41581-018-0057-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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40
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Gupta S, Köttgen A, Hoxha E, Brenchley P, Bockenhauer D, Stanescu HC, Kleta R. Genetics of membranous nephropathy. Nephrol Dial Transplant 2018; 33:1493-1502. [PMID: 29126273 PMCID: PMC6113634 DOI: 10.1093/ndt/gfx296] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 09/12/2017] [Indexed: 12/22/2022] Open
Abstract
An HLA-DR3 association with membranous nephropathy (MN) was described in 1979 and additional evidence for a genetic component to MN was suggested in 1984 in reports of familial MN. In 2009, a pathogenic autoantibody was identified against the phospholipase A2 receptor 1 (PLA2R1). Here we discuss the genetic studies that have proven the association of human leucocyte antigen class II and PLA2R1 variants and disease in MN. The common variants in PLA2R1 form a haplotype that is associated with disease incidence. The combination of the variants in both genes significantly increases the risk of disease by 78.5-fold. There are important genetic ethnic differences in MN. Disease outcome is difficult to predict and attempts to correlate the genetic association to outcome have so far not been helpful in a reproducible manner. The role of genetic variants may not only extend beyond the risk of disease development, but can also help us understand the underlying molecular biology of the PLA2R1 and its resultant pathogenicity. The genetic variants identified thus far have an association with disease and could therefore become useful biomarkers to stratify disease risk, as well as possibly identifying novel drug targets in the near future.
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Affiliation(s)
- Sanjana Gupta
- University College London–Centre for Nephrology, London, UK
| | - Anna Köttgen
- Institute of Genetic Epidemiology, Medical Center and Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Elion Hoxha
- Medizinische Klinik und Poliklinik III, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Paul Brenchley
- Institute of Cardiovascular Sciences, University of Manchester, Manchester, UK
| | | | | | - Robert Kleta
- University College London–Centre for Nephrology, London, UK
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HLA class II alleles differing by a single amino acid associate with clinical phenotype and outcome in patients with primary membranous nephropathy. Kidney Int 2018; 94:974-982. [PMID: 30173899 DOI: 10.1016/j.kint.2018.06.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 05/19/2018] [Accepted: 06/01/2018] [Indexed: 11/23/2022]
Abstract
Genome-wide associations and HLA genotyping have revealed associations between HLA alleles and susceptibility to primary membranous nephropathy. However, associations with clinical phenotypes and kidney outcome are poorly defined. We previously identified DRB1*1501 and DRB1*0301 as independent risk alleles for primary membranous nephropathy. Here, we investigated HLA associations with demographic characteristics, anti-phospholipase A2 receptor (PLA2R) antibody, treatment response and kidney outcome after a median follow-up of 52 months in 258 patients. DRB1*0301, but not DRB1*1501, was associated with a significantly higher level of PLA2R antibody (odds ratio 1.58, 95% confidence interval 1.13-2.22). Although DRB1*1502, which differs from DRB1*1501 by a single amino acid, was not a risk allele for primary membranous nephropathy (odds ratio 1.01), it was associated with significantly lower estimated glomerular filtration rates both at baseline (1.79, 1.18-2.72) and at last follow-up (1.72, 1.17-2.53), a significantly worse renal outcome by Kaplan-Meier analysis and a significantly higher risk of end-stage renal disease by Cox regression analysis (hazard ratio 4.52, 1.22-16.74). Nevertheless, the absence of remission remained the only independent risk factor for end-stage renal disease by multivariate analysis. DRB1*1502 was also associated with a significantly higher median PLA2R antibody level [161.4 vs. 36.3 U/mL] and showed interaction with DRB1*0301 for this variable. Thus, HLA genes control PLA2R antibody production and primary membranous nephropathy severity and outcome. Additionally, DRB1*1502 behaves like a modifier gene with a strong predictor value when associated with HLA risk alleles. Other modifier genes need further investigations in larger cohorts.
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Venous thromboembolism, factor VIII and chronic kidney disease. Thromb Res 2018; 170:10-19. [PMID: 30081388 DOI: 10.1016/j.thromres.2018.07.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 07/30/2018] [Indexed: 12/12/2022]
Abstract
Chronic kidney disease (CKD) affects 30 million Americans and is associated with approximately a two-fold increased risk of venous thromboembolism (VTE). There is a graded increased risk of VTE across declining kidney function, as measured by estimated glomerular filtration rate (eGFR) and albuminuria. When patients with end-stage kidney disease (ESKD) experience VTE they are more likely than the general population to be hospitalized and they have a higher mortality. The incidence and consequences of VTE may also differ depending on the cause of kidney disease. In addition, kidney transplant patients with VTE are at a greater risk for death and graft loss than transplant patients without VTE. The reasons that patients with CKD are at increased risk of VTE are not well understood, but recent data suggest that factor VIII is a mediator. Factor VIII is an essential cofactor in the coagulation cascade and a strong risk factor for VTE in general. It is inversely correlated with eGFR and prospective studies demonstrate that factor VIII activity predicts incident CKD and rapid eGFR decline. The etiology of CKD may also influence factor VIII levels. This review summarizes the epidemiology VTE in CKD and reviews the biochemistry of factor VIII and determinants of its levels, including von Willebrand factor and ABO blood group. We explore mechanisms by which the complications of CKD might give rise to higher factor VIII and suggests future research directions to understand how factor VIII and CKD are linked.
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Limou S, Vince N, Parsa A. Lessons from CKD-Related Genetic Association Studies-Moving Forward. Clin J Am Soc Nephrol 2018; 13:140-152. [PMID: 29242368 PMCID: PMC5753320 DOI: 10.2215/cjn.09030817] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Over the past decade, genetic association studies have uncovered numerous determinants of kidney function in the general, diabetic, hypertensive, CKD, ESRD, and GN-based study populations (e.g., IgA nephropathy, membranous nephropathy, FSGS). These studies have led to numerous novel and unanticipated findings, which are helping improve our understanding of factors and pathways affecting both normal and pathologic kidney function. In this review, we report on major discoveries and advances resulting from this rapidly progressing research domain. We also predict some of the next steps the nephrology community should embrace to accelerate the identification of genetic and molecular processes leading to kidney dysfunction, pathophysiologically based disease subgroups, and specific therapeutic targets, as we attempt to transition toward a more precision-based medicine approach.
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Affiliation(s)
- Sophie Limou
- Centre de Recherche en Transplantation et Immunologie Unité Mixte de Recherche 1064, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Nantes, Nantes, France
- Institut de Transplantation Urologie et Néphrologie, Centre Hospitalier Universitaire Nantes, Nantes, France
- Ecole Centrale de Nantes, Nantes, France
- Basic Science Program, Basic Research Laboratory, National Cancer Institute/National Institutes of Health, Leidos Biomedical Research Inc., Frederick National Laboratory, Frederick, Maryland
| | - Nicolas Vince
- Centre de Recherche en Transplantation et Immunologie Unité Mixte de Recherche 1064, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Nantes, Nantes, France
- Institut de Transplantation Urologie et Néphrologie, Centre Hospitalier Universitaire Nantes, Nantes, France
| | - Afshin Parsa
- Division of Nephrology, University of Maryland School of Medicine, Baltimore, Maryland; and
- Department of Medicine, Baltimore VA Medical Center, Baltimore, Maryland
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Adeyemo A, Esezobor C, Solarin A, Abeyagunawardena A, Kari JA, El Desoky S, Greenbaum LA, Kamel M, Kallash M, Silva C, Young A, Hunley TE, de Jesus-Gonzalez N, Srivastava T, Gbadegesin R. HLA-DQA1 and APOL1 as Risk Loci for Childhood-Onset Steroid-Sensitive and Steroid-Resistant Nephrotic Syndrome. Am J Kidney Dis 2017; 71:399-406. [PMID: 29277510 DOI: 10.1053/j.ajkd.2017.10.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 10/05/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND Few data exist for the genetic variants underlying the risk for steroid-sensitive nephrotic syndrome (SSNS) in children. The objectives of this study were to evaluate HLA-DQA1 and APOL1 variants as risk factors for SSNS in African American children and use classic HLA antigen types and amino acid inference to refine the HLA-DQA1 association. STUDY DESIGN Case-control study. SETTING & PARTICIPANTS African American children with SSNS or steroid-resistant nephrotic syndrome (SRNS) were enrolled from Duke University and centers participating in the Midwest Pediatric Nephrology Consortium. FACTOR Genetic variants in HLA-DQA1 (C34Y [rs1129740]; F41S [rs1071630]) and APOL1 high-risk alleles. OUTCOMES SSNS and SRNS. MEASUREMENTS Direct sequencing for the HLA-DQA1 and APOL1 variants in 115 African American children (65 with SSNS and 50 with SRNS). Imputation of classic HLA alleles and amino acids was done in 363 South Asian children. RESULTS The 2 HLA-DQA1 variants were significantly associated with SSNS in African American children (C34Y: P=5.7 × 10-11; OR, 3.53; 95% CI, 2.33-5.42; F41S: P=1.2 × 10-13; OR, 4.08; 95% CI, 2.70-6.28), but not with SRNS (C34Y: P=0.6; F41S: P=0.2). APOL1 high-risk variants were not associated with SSNS (P=0.5) but showed significant associations with SRNS (P=1.04 × 10-7; OR, 4.17; 95% CI, 2.23-7.64). HLA-DQA1*0201, HLA-DQB1*0201, and HLA-DRB1*0701 were the classic HLA alleles with the most significant associations with SSNS risk. The most significantly associated amino acid positions were HLA-DQα1 56 and 76 (both P=2.8 × 10-7). Conditional analysis revealed that these variants most likely account for the observed association. LIMITATIONS Modest sample size and limited statistical power to detect small to moderate effect sizes. Children studied may not be representative of all African American children in the United States. CONCLUSIONS HLA-DQA1 is a risk locus for SSNS, but not SRNS, in African American children, consistent with its role in SSNS risk in children of European, Asian, and African ancestries. There is little evidence of a significant role for the APOL1 high-risk alleles in childhood SSNS in African American children. Refinement of the HLA-DQA1 association identified the critical classic HLA antigen types and amino acids of the HLA-DQ α1 molecule.
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Affiliation(s)
- Adebowale Adeyemo
- Center for Research on Genomics and Global Health, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD.
| | - Christopher Esezobor
- Department of Pediatrics, Lagos University Teaching Hospital (LUTH), Lagos, Nigeria
| | - Adaobi Solarin
- Department of Pediatrics, Lagos State University Teaching Hospital (LASUTH), Lagos, Nigeria
| | | | - Jameela A Kari
- Pediatric Nephrology Center of Excellence, Department of Pediatrics, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sherif El Desoky
- Pediatric Nephrology Center of Excellence, Department of Pediatrics, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Larry A Greenbaum
- Division of Pediatric Nephrology, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA
| | - Margret Kamel
- Division of Pediatric Nephrology, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA
| | - Mahmoud Kallash
- Department of Pediatrics, State University of New York, Buffalo, NY
| | - Cynthia Silva
- Division of Nephrology, Connecticut Children's Hospital, Hartford, CT
| | - Alex Young
- Division of Nephrology, Department of Pediatrics, and Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC
| | - Tracey E Hunley
- Division of Nephrology, Department of Pediatrics, Vanderbilt University, Nashville, TN
| | - Nilka de Jesus-Gonzalez
- Department of Pediatrics, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
| | - Tarak Srivastava
- Department of Nephrology, Children Mercy Hospital, Kansas City, MO
| | - Rasheed Gbadegesin
- Division of Nephrology, Department of Pediatrics, and Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC.
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Wunnenburger S, Schultheiss UT, Walz G, Hausknecht B, Ekici AB, Kronenberg F, Eckardt KU, Köttgen A, Wuttke M. Associations between genetic risk variants for kidney diseases and kidney disease etiology. Sci Rep 2017; 7:13944. [PMID: 29066732 PMCID: PMC5655008 DOI: 10.1038/s41598-017-13356-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 09/21/2017] [Indexed: 01/10/2023] Open
Abstract
Chronic kidney disease (CKD) is a global health problem with a genetic component. Genome-wide association studies have identified variants associated with specific CKD etiologies, but their genetic overlap has not been well studied. This study examined SNP associations across different CKD etiologies and CKD stages using data from 5,034 CKD patients of the German Chronic Kidney Disease study. In addition to confirming known associations, a systemic lupus erythematosus-associated risk variant at TNXB was also associated with CKD attributed to type 1 diabetes (p = 2.5 × 10-7), a membranous nephropathy-associated variant at HLA-DQA1 was also associated with CKD attributed to systemic lupus erythematosus (p = 5.9 × 10-6), and an IgA risk variant at HLA-DRB1 was associated with both CKD attributed to granulomatosis with polyangiitis (p = 2.0 × 10-4) and to type 1 diabetes (p = 4.6 × 10-11). Associations were independent of additional risk variants in the respective genetic regions. Evaluation of CKD stage showed a significant association of the UMOD risk variant, previously identified in population-based studies for association with kidney function, for advanced (stage ≥G3b) compared to early-stage CKD (≤stage G2). Shared genetic associations across CKD etiologies and stages highlight the role of the immune response in CKD. Association studies with detailed information on CKD etiology can reveal shared genetic risk variants.
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Affiliation(s)
- Sebastian Wunnenburger
- Institute of Genetic Epidemiology, Medical Center - University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Ulla T Schultheiss
- Institute of Genetic Epidemiology, Medical Center - University of Freiburg, Faculty of Medicine, Freiburg, Germany
- Division of Nephrology, University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Gerd Walz
- Division of Nephrology, University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Birgit Hausknecht
- Department of Nephrology and Hypertension, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Arif B Ekici
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Florian Kronenberg
- Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | - Kai-Uwe Eckardt
- Department of Nephrology and Hypertension, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Anna Köttgen
- Institute of Genetic Epidemiology, Medical Center - University of Freiburg, Faculty of Medicine, Freiburg, Germany.
| | - Matthias Wuttke
- Institute of Genetic Epidemiology, Medical Center - University of Freiburg, Faculty of Medicine, Freiburg, Germany
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Obrador GT, Schultheiss UT, Kretzler M, Langham RG, Nangaku M, Pecoits-Filho R, Pollock C, Rossert J, Correa-Rotter R, Stenvinkel P, Walker R, Yang CW, Fox CS, Köttgen A. Genetic and environmental risk factors for chronic kidney disease. Kidney Int Suppl (2011) 2017; 7:88-106. [PMID: 30675423 DOI: 10.1016/j.kisu.2017.07.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In order to change the current state of chronic kidney disease knowledge and therapeutics, a fundamental improvement in the understanding of genetic and environmental causes of chronic kidney disease is essential. This article first provides an overview of the existing knowledge gaps in our understanding of the genetic and environmental causes of chronic kidney disease, as well as their interactions. The second part of the article formulates goals that should be achieved in order to close these gaps, along with suggested timelines and stakeholders that are to be involved. A better understanding of genetic and environmental factors and their interactions that influence kidney function in healthy and diseased conditions can provide novel insights into renal physiology and pathophysiology and result in the identification of novel therapeutic or preventive targets to tackle the global public health care problem of chronic kidney disease.
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Affiliation(s)
- Gregorio T Obrador
- Department of Epidemiology, Biostatistics and Public Health, Universidad Panamericana School of Medicine, Mexico City, Mexico
| | - Ulla T Schultheiss
- Institute of Genetic Epidemiology, Medical Center and Faculty of Medicine-University of Freiburg, Freiburg, Germany.,Renal Division, Department of Medicine IV, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Matthias Kretzler
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA.,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Robyn G Langham
- Monash Rural Health, Monash University, Clayton VIC, Australia
| | - Masaomi Nangaku
- Department of Hemodialysis and Apheresis, Division of Nephrology and Endocrinology, University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Roberto Pecoits-Filho
- Department of Internal Medicine, School of Medicine, Pontificia Universidade Catolica do Paraná, Curitiba, Brazil
| | - Carol Pollock
- Kolling Institute of Medical Research, University of Sydney, Sydney, NSW, Australia
| | | | - Ricardo Correa-Rotter
- Department of Nephrology and Mineral Metabolism, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zuibrán, Mexico City, Mexico
| | - Peter Stenvinkel
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
| | - Robert Walker
- Department of Medicine, University of Otago, Dunedin, New Zealand
| | - Chih-Wei Yang
- Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan
| | - Caroline S Fox
- Genetics and Pharmacogenomics, Merck Research Laboratories, Boston, Massachusetts, USA
| | - Anna Köttgen
- Institute of Genetic Epidemiology, Medical Center and Faculty of Medicine-University of Freiburg, Freiburg, Germany
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Karp AM, Gbadegesin RA. Genetics of childhood steroid-sensitive nephrotic syndrome. Pediatr Nephrol 2017; 32:1481-1488. [PMID: 27470160 PMCID: PMC5276801 DOI: 10.1007/s00467-016-3456-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 06/27/2016] [Accepted: 06/29/2016] [Indexed: 02/07/2023]
Abstract
The pathogenesis of childhood-onset nephrotic syndrome (NS), disparity in incidence of NS among races, and variable responses to therapies in children with NS have defied explanation to date. In the last 20 years over 50 genetic causes of steroid-resistant nephrotic syndrome (SRNS) have been identified, and at least two disease loci for two pathologic variants of SRNS (focal segmental glomerulosclerosis and membranous nephropathy) have been defined. However, the genetic causes and risk loci for steroid-sensitive nephrotic syndrome (SSNS) remain elusive, partly because SSNS is relatively rare and also because cases of SSNS vary widely in phenotypic expression over time. A recent study of a well-defined modest cohort of children with SSNS identified variants in HLA-DQA1 as a risk factor for SSNS. Here we review what is currently known about the genetics of SSNS and also discuss how recent careful phenotypic and genomic studies reinforce the role of adaptive immunity in the molecular mechanisms of SSNS.
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Affiliation(s)
- Alana M. Karp
- Department of Pediatrics, Division of Nephrology, Emory University, Atlanta, GA, USA
| | - Rasheed A. Gbadegesin
- Department of Pediatrics, Division of Nephrology, Duke University Medical Center, Durham, NC,Duke Molecular Physiology Institute, Duke University, Durham, NC,To whom correspondence should be addressed:
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Kronbichler A, Oh J, Meijers B, Mayer G, Shin JI. Recent Progress in Deciphering the Etiopathogenesis of Primary Membranous Nephropathy. BIOMED RESEARCH INTERNATIONAL 2017; 2017:1936372. [PMID: 28904948 PMCID: PMC5585565 DOI: 10.1155/2017/1936372] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 07/18/2017] [Indexed: 12/24/2022]
Abstract
Primary membranous nephropathy (MN) is the leading cause of nephrotic syndrome in adults. Discovery of several antibodies has contributed to an increased understanding of MN. Antibodies against the M-type phospholipase A2 receptor (PLA2R) are present in 50-100% with primary MN and are associated with a lower frequency of spontaneous remission. High levels are linked with a higher probability of treatment resistance, higher proteinuria, and impaired renal function, as well as a more rapid decline of kidney function during follow-up. Immunologic remission precedes reduction of proteinuria by months. Pretransplant evaluation of PLA2R antibodies is warranted to predict recurrence of disease following renal transplantation. Several risk alleles related to the PLA2R1 gene and within the HLA loci have been identified, whereas epitope spreading of PLA2R may predict treatment response. More recently, thrombospondin type 1 domain-containing 7A (THSD7A) antibodies have been discovered in primary MN. Several other rare antigens have been described, including antibodies against neutral endopeptidase as a cause of antenatal MN and circulating cationic bovine serum albumin as an antigen with implications in childhood MN. This review focuses on the progress with a special focus on diagnostic accuracy, predictive value, and treatment implications of the established and proposed antigens.
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Affiliation(s)
- Andreas Kronbichler
- Department of Internal Medicine IV (Nephrology and Hypertension), Medical University Innsbruck, Anichstraße 35, 6020 Innsbruck, Austria
| | - Jun Oh
- Pediatric Nephrology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246 Hamburg, Germany
| | - Björn Meijers
- Department of Nephrology, UZ Leuven, Leuven, Belgium
- Department of Immunology and Microbiology, KU Leuven, Leuven, Belgium
| | - Gert Mayer
- Department of Internal Medicine IV (Nephrology and Hypertension), Medical University Innsbruck, Anichstraße 35, 6020 Innsbruck, Austria
| | - Jae Il Shin
- Department of Pediatrics, Yonsei University College of Medicine, Severance Children's Hospital, Seoul, Republic of Korea
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Abstract
The phospholipase A2 receptor (PLA2R) and thrombospondin type-1 domain-containing 7A (THSD7A) are the two major autoantigens in primary membranous nephropathy (MN), and define two molecular subclasses of this disease. Both proteins are large transmembrane glycoproteins expressed by the podocyte, and both induce IgG4-predominant humoral immune responses that produce circulating autoantibodies that can be used clinically for diagnostic and monitoring purposes. The biologic roles of these proteins remain speculative, although several features of THSD7A suggest a role in adhesion. PLA2R-associated MN was initially found to associate with risk alleles within HLA-DQA1, but subsequent studies have shifted the focus to the HLA-DRB locus. Three distinct humoral epitope-containing regions have been defined within the extracellular portion of PLA2R, and it appears that the number of targeted epitopes may determine disease severity. Although similar information is not yet available for THSD7A-associated MN, this form of MN may have a unique association with malignancy. Finally, it appears likely that other autoantigens in primary MN exist. Although protocols similar to those that identified PLA2R and THSD7A may be successful in the identification of novel antigenic targets in MN, newer techniques such as laser-capture mass spectrometry or protein arrays may be helpful as well.
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Affiliation(s)
- Laurence H Beck
- Renal Section, Boston Medical Center, Boston University School of Medicine, Boston, Massachusetts
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Mladkova N, Kiryluk K. Genetic Complexities of the HLA Region and Idiopathic Membranous Nephropathy. J Am Soc Nephrol 2017; 28:1331-1334. [PMID: 28396523 DOI: 10.1681/asn.2017030283] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Affiliation(s)
- Nikol Mladkova
- Division of Nephrology, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Krzysztof Kiryluk
- Division of Nephrology, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York
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