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Abstract
C4d is a byproduct of the activation of the classic and lectin complement pathways. Being routinely used as a marker for antibody-mediated rejection, the significance of C4d in native kidney disease is currently being widely studied. We evaluated glomerular and extraglomerular C4d staining in 82 biopsies of proliferative and nonproliferative glomerulonephritis diagnosed in our institution. The staining pattern of C4d was tabulated in various glomerular diseases. All biopsies of membranous nephropathy including membranous lupus nephritis (Class V) and immune complex-mediated membranoproliferative glomerulonephritis (MPGN) consistently showed C4d deposits along glomerular basement membrane mirroring the location of immunoglobulin and complement in these conditions. Conversely, other glomerular diseases like IgA nephropathy, postinfectious glomerulonephritis, focal segmental glomerulosclerosis, minimal change disease, and diabetic nephropathy showed variable mesangial and capillary wall C4d deposits. To summarize, the consistent pattern of C4d staining in membranous nephropathy (primary and secondary)and immune complex-mediated MPGN can be used as a valuable adjunct tool in establishing the diagnosis, especially when immunofluorescence findings are limited by inadequate sampling.C4d reactivity in other glomerular diseases are variable and may not aid as a diagnostic tool in renal biopsy evaluation.
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Affiliation(s)
- Immanuel Pradeep
- Department of Pathology and Laboratory Medicine, All India Institute of Medical Sciences, Bibinagar, Hyderabad, India
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Caravaca-Fontán F, Gutiérrez E, Sevillano ÁM, Praga M. Targeting complement in IgA nephropathy. Clin Kidney J 2023; 16:ii28-ii39. [PMID: 38053977 PMCID: PMC10695513 DOI: 10.1093/ckj/sfad198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Indexed: 12/07/2023] Open
Abstract
Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. Recent years have witnessed significant improvements in the understanding of the pathogenesis of IgAN and particularly, the pathogenic role of complement activation. The alternative complement pathway is the major complement cascade activator in IgAN, and glomerular C3 deposition has been shown to correlate with disease progression. In addition, several studies have provided insight into the pathogenic role of factor H-related proteins -1 and -5 in IgAN, as independent players in complement dysregulation. The lectin pathway has also been shown to be associated with the severity of IgAN. Glomerular deposition of C4d has been associated with increased histologic disease activity, faster decline in estimated glomerular filtration rate and higher risk of kidney failure. On the other hand, although overlooked in the Oxford classification, numerous studies have shown that the coexistence of thrombotic microangiopathy in IgAN is a significant indicator of a poorer prognosis. All the breakthroughs in the understanding of the contributing role of complement in IgAN have paved the way for the development of new complement-targeted therapies in this disease. Several ongoing trials are evaluating the efficacy of new agents against factor B (iptacopan, Ionis-FB-LRX), C3 (pegcetacoplan), factor D (vemircopan, pelecopan), C5 (ravulizumab, cemdisiran) and C5a receptor 1 (avacopan). In this study, we provide a comprehensive review of the role of complement in IgAN, including the emerging mechanisms of complement activation and the promising potential of complement inhibitors as a viable treatment option for IgAN.
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Affiliation(s)
- Fernando Caravaca-Fontán
- Department of Nephrology, Instituto de Investigación Hospital 12 de Octubre (imas12), Madrid, Spain
| | - Eduardo Gutiérrez
- Department of Nephrology, Hospital Universitario 12 de Octubre (imas12), Madrid, Spain
| | - Ángel M Sevillano
- Department of Nephrology, Hospital Universitario 12 de Octubre (imas12), Madrid, Spain
| | - Manuel Praga
- Department of Nephrology, Instituto de Investigación Hospital 12 de Octubre (imas12), Madrid, Spain
- Department of Medicine, Complutense University, Madrid, Spain
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3
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Cattran DC, Floege J, Coppo R. Evaluating Progression Risk in Patients With Immunoglobulin A Nephropathy. Kidney Int Rep 2023; 8:2515-2528. [PMID: 38106572 PMCID: PMC10719597 DOI: 10.1016/j.ekir.2023.09.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 09/05/2023] [Accepted: 09/08/2023] [Indexed: 12/19/2023] Open
Abstract
The highly variable rate of decline in kidney function in patients with immunoglobulin A nephropathy (IgAN) provides a major clinical challenge. Predicting which patients will progress to kidney failure, and how quickly, is difficult. Multiple novel therapies are likely to be approved in the short-term, but clinicians lack the tools to identify patients most likely to benefit from specific treatments at the right time. Noninvasive and validated markers for selecting at-risk patients and longitudinal monitoring are urgently needed. This review summarizes what is known about demographic, clinical, and histopathologic prognostic markers in the clinician's toolkit, including the International IgAN Prediction Tool. We also briefly review what is known on these topics in children and adolescents with IgAN. Although helpful, currently used markers leave clinicians heavily reliant on histologic features from the diagnostic kidney biopsy and standard clinical data to guide treatment choice, and very few noninvasive markers reflect treatment efficacy over time. Novel prognostic and predictive markers are under clinical investigation, with considerable progress being made in markers of complement activation. Other areas of research are the interplay between gut microbiota and galactose-deficient IgA1 expression; microRNAs; imaging; artificial intelligence; and markers of fibrosis. Given the rate of therapeutic advancement, the remaining gaps in biomarker research need to be addressed. We finish by describing our route to clinical utility of predictive and prognostic markers in IgAN. This route will provide us with the chance to improve IgAN prognosis by using robust, clinically practical markers to inform patient care.
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Affiliation(s)
| | - Jürgen Floege
- Division of Nephrology and Clinical Immunology, RWTH Aachen University, Aachen, Germany
| | - Rosanna Coppo
- Fondazione Ricerca Molinette, Regina Margherita Hospital, Turin, Italy
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4
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Abstract
IgA nephropathy (IgAN), the most prevalent primary glomerulonephritis worldwide, carries a considerable lifetime risk of kidney failure. Clinical manifestations of IgAN vary from asymptomatic with microscopic or intermittent macroscopic haematuria and stable kidney function to rapidly progressive glomerulonephritis. IgAN has been proposed to develop through a 'four-hit' process, commencing with overproduction and increased systemic presence of poorly O-glycosylated galactose-deficient IgA1 (Gd-IgA1), followed by recognition of Gd-IgA1 by antiglycan autoantibodies, aggregation of Gd-IgA1 and formation of polymeric IgA1 immune complexes and, lastly, deposition of these immune complexes in the glomerular mesangium, leading to kidney inflammation and scarring. IgAN can only be diagnosed by kidney biopsy. Extensive, optimized supportive care is the mainstay of therapy for patients with IgAN. For those at high risk of disease progression, the 2021 KDIGO Clinical Practice Guideline suggests considering a 6-month course of systemic corticosteroid therapy; however, the efficacy of systemic steroid treatment is under debate and serious adverse effects are common. Advances in understanding the pathophysiology of IgAN have led to clinical trials of novel targeted therapies with acceptable safety profiles, including SGLT2 inhibitors, endothelin receptor blockers, targeted-release budesonide, B cell proliferation and differentiation inhibitors, as well as blockade of complement components.
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Affiliation(s)
- Eleni Stamellou
- Department of Nephrology, School of Medicine, University of Ioannina, Ioannina, Greece
- Department of Nephrology and Clinical Immunology, RWTH Aachen University Hospital, Aachen, Germany
| | - Claudia Seikrit
- Department of Nephrology and Clinical Immunology, RWTH Aachen University Hospital, Aachen, Germany
| | - Sydney C W Tang
- Division of Nephrology, Department of Medicine, University of Hong Kong, Hong Kong, China
| | - Peter Boor
- Department of Nephrology and Clinical Immunology, RWTH Aachen University Hospital, Aachen, Germany
- Department of Pathology, RWTH Aachen University, Aachen, Germany
| | - Vladimir Tesař
- Department of Nephrology, 1st Faculty of Medicine and General University Hospital, Charles University, Prague, Czech Republic
| | - Jürgen Floege
- Department of Nephrology and Clinical Immunology, RWTH Aachen University Hospital, Aachen, Germany
| | - Jonathan Barratt
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Rafael Kramann
- Department of Nephrology and Clinical Immunology, RWTH Aachen University Hospital, Aachen, Germany.
- Department of Internal Medicine, Nephrology and Transplantation, Erasmus Medical Center, Rotterdam, Netherlands.
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Ștefan G, Jullien P, Masson I, Alamartine E, Mariat C, Maillard N. Circulating alternative pathway complement cleavage factor Bb is associated with vascular lesions and outcomes in IgA nephropathy. Nephrol Dial Transplant 2023; 38:ii11-ii18. [PMID: 37816675 DOI: 10.1093/ndt/gfad163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Indexed: 10/12/2023] Open
Abstract
BACKGROUND Complement alternative pathway (AP) activation is linked to immunoglobulin A nephropathy (IgAN) prognosis severity, but Bb fragment's role is unclear. We examined the relationship between serum Bb fragment concentration at IgAN diagnosis and disease activity and outcomes. METHODS This retrospective study included 125 biopsy-proven IgAN patients [age 39.9 years, 75% male, estimated glomerular filtration rate (eGFR) 82 ml/min, proteinuria 0.5 g/day] enrolled from 1984 to 2010 and followed for a minimum of 18 months. Monitoring continued until the last follow-up, end-stage kidney disease (ESKD) or death. Serum Bb fragment was measured using an enzyme-linked immunosorbent assay at diagnosis. Oxford classification and global optical score (GOS) were utilized for pathology assessment. RESULTS Patients were followed for a median of 16 years; 42% developed chronic kidney disease stage ≥3, 19% reached ESKD and 9% died. Serum Bb fragment concentration negatively correlated with eGFR values at the last follow-up and positively with vascular and tubular histopathological indices. In univariate Cox regression analyses, higher Bb fragment concentration was associated with ESKD alongside older age, increased body mass index, arterial hypertension, lower eGFR, higher proteinuria, E1, S1, T1-2, GOS and corticotherapy. Patients with Bb levels ≥14.3 μg/ml had shorter mean kidney survival time (19.5 versus 22.7 years, P = .07); after adjusting for progression risk factors, the association persisted [hazard ratio 4.76 (95% confidence interval 1.56-14.43)]. CONCLUSIONS Serum Bb fragment concentration at diagnosis may predict long-term IgAN outcomes, potentially due to AP activation at the endothelial surface. Further research is needed to confirm these results and evaluate Bb fragment's role in IgAN management.
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Affiliation(s)
- Gabriel Ștefan
- Service de Néphrologie, Hôpital Nord CHU Saint Etienne, Saint Etienne, France
- University of Medicine and Pharmacy "Carol Davila", Nephrology Department, Bucharest, Romania
| | - Perrine Jullien
- Service de Néphrologie, Hôpital Nord CHU Saint Etienne, Saint Etienne, France
- Groupe Immunité muqueuse et agents pathogènes (GIMAP, team 15 CIRI INSERM U1111/UMR5108), Saint Etienne, France
| | - Ingrid Masson
- Service de Néphrologie, Hôpital Nord CHU Saint Etienne, Saint Etienne, France
- Groupe Immunité muqueuse et agents pathogènes (GIMAP, team 15 CIRI INSERM U1111/UMR5108), Saint Etienne, France
| | - Eric Alamartine
- Service de Néphrologie, Hôpital Nord CHU Saint Etienne, Saint Etienne, France
- Groupe Immunité muqueuse et agents pathogènes (GIMAP, team 15 CIRI INSERM U1111/UMR5108), Saint Etienne, France
| | - Christophe Mariat
- Service de Néphrologie, Hôpital Nord CHU Saint Etienne, Saint Etienne, France
- Groupe Immunité muqueuse et agents pathogènes (GIMAP, team 15 CIRI INSERM U1111/UMR5108), Saint Etienne, France
| | - Nicolas Maillard
- Service de Néphrologie, Hôpital Nord CHU Saint Etienne, Saint Etienne, France
- Groupe Immunité muqueuse et agents pathogènes (GIMAP, team 15 CIRI INSERM U1111/UMR5108), Saint Etienne, France
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Ruan Y, Hong F, Lin M, Wang C, Lian F, Cao F, Yang G, Huang L, Huang Q. Clinicopathological characteristics, risk factors and prognostic value of intrarenal vascular lesions in IgA nephropathy. Eur J Intern Med 2023; 117:91-97. [PMID: 37451907 DOI: 10.1016/j.ejim.2023.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/23/2023] [Accepted: 07/07/2023] [Indexed: 07/18/2023]
Abstract
BACKGROUND The aim was to study clinicopathological characteristics, risk factors and renal outcome in IgA nephropathy (IgAN) patients with vascular lesions. METHODS We enrolled a Chinese cohort with 458 biopsy-confirmed primary IgAN patients for a retrospective analysis. They were divided into three groups according to vascular lesions: no vascular lesions (n = 239), arterio-/arteriolosclerosis (n = 181) and microangiopathic lesions (n = 38). The clinicopathological features and renal outcome were recorded. In univariate and multivariate models, association between vascular lesions and renal outcome and vascular lesions associated clinical factors were analyzed. RESULTS Patients with vascular lesions presented worse clinical characteristics with regard to blood pressure and kidney function, and segmental glomerulosclerosis (S1), tubular atrophy/interstitial fibrosis (T1/2) and lymphocytes and monocytes infiltration were more common. Furthermore, older age, hyperuricemia, proteinuria, global glomerulosclerosis and endocapillary hypercellularity (E1) were more severe in patients with simple arterio-/arteriolosclerosis. By multivariate logistic regression, age, MAP and eGFR were significantly associated with vascular lesions. Vascular lesions, especially arterio-/arteriolosclerosis, were significantly associated with poorer renal survival in IgAN patients, and renal survival was similar whether patients with arterio-/arteriolosclerosis received immunosuppressive therapy. In addition to eGFR, arterio-/arteriolosclerosis, along with arterial intimal fibrosis, was an independent predictor for renal survival in multivariate Cox analyses. CONCLUSION IgAN patients with vascular lesions, especially with arterio-/arteriolosclerosis, presented more severe clinicopathological features. Renal function, blood pressure and age contributed to distinguishing patients with vascular lesions. Arterio-/arteriolosclerosis lesions were associated with poorer renal survival.
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Affiliation(s)
- Yiping Ruan
- Department of Nephrology, Fujian Provincial Clinical College, Fujian Provincial Hospital, Fujian Medical University, Fuzhou 350001, China.
| | - Fuyuan Hong
- Department of Nephrology, Fujian Provincial Clinical College, Fujian Provincial Hospital, Fujian Medical University, Fuzhou 350001, China
| | - Miao Lin
- Department of Nephrology, Fujian Provincial Clinical College, Fujian Provincial Hospital, Fujian Medical University, Fuzhou 350001, China
| | - Chen Wang
- Department of Pathology, Fujian Provincial Hospital, Fuzhou, China
| | - Fayang Lian
- Epidemiology and Clinical Research Unit, Fujian Provincial Hospital, Fuzhou, China
| | - Fang Cao
- Department of Nephrology, Fujian Provincial Clinical College, Fujian Provincial Hospital, Fujian Medical University, Fuzhou 350001, China
| | - Guokai Yang
- Department of Nephrology, Fujian Provincial Clinical College, Fujian Provincial Hospital, Fujian Medical University, Fuzhou 350001, China
| | - Lanting Huang
- Department of Nephrology, Fujian Provincial Clinical College, Fujian Provincial Hospital, Fujian Medical University, Fuzhou 350001, China
| | - Qiaoyun Huang
- Department of Computer Engineering, Fuzhou University Zhicheng College, Fuzhou, China
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Bednarova K, Mjøen G, Hruba P, Modos I, Voska L, Kollar M, Viklicky O. A novel prognostic nomogram predicts premature failure of kidney allografts with IgA nephropathy recurrence. Nephrol Dial Transplant 2023; 38:2627-2636. [PMID: 37202220 PMCID: PMC10660147 DOI: 10.1093/ndt/gfad097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Indexed: 05/20/2023] Open
Abstract
BACKGROUND Recurrence of immunoglobulin A nephropathy (IgAN) limits graft survival in kidney transplantation. However, predictors of a worse outcome are poorly understood. METHODS Among 442 kidney transplant recipients (KTRs) with IgAN, 83 (18.8%) KTRs exhibited biopsy-proven IgAN recurrence between 1994 and 2020 and were enrolled in the derivation cohort. A multivariable Cox model predicting allograft loss based on clinical data at the biopsy and a web-based nomogram were developed. The nomogram was externally validated using an independent cohort (n = 67). RESULTS Patient age <43 years {hazard ratio [HR] 2.20 [95% confidence interval (CI) 1.41-3.43], P < .001}, female gender [HR 1.72 (95% CI 1.07-2.76), P = .026] and retransplantation status [HR 1.98 (95% CI 1.13-3.36), P = .016] were identified as independent risk factors for IgAN recurrence. Patient age <43 years [HR 2.77 (95% CI 1.17-6.56), P = .02], proteinuria >1 g/24 hours [HR 3.12 (95% CI 1.40-6.91), P = .005] and C4d positivity [HR 2.93 (95% CI 1.26-6.83), P = .013] were found to be associated with graft loss in patients with IgAN recurrence. A nomogram predicting graft loss was constructed based on clinical and histological variables, with a C statistic of 0.736 for the derivation cohort and 0.807 for the external validation cohort. CONCLUSIONS The established nomogram identified patients with recurrent IgAN at risk for premature graft loss with good predictive performance.
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Affiliation(s)
- Kamila Bednarova
- Department of Nephrology, Transplant Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- 1st Medical Faculty, Charles University, Prague, Czech Republic
| | - Geir Mjøen
- Department of Nephrology, Oslo University Hospital, Oslo, Norway
| | - Petra Hruba
- Transplant Laboratory, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Istvan Modos
- Department of Informatics, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Ludek Voska
- Clinical and Transplant Pathology Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Marek Kollar
- Clinical and Transplant Pathology Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Ondrej Viklicky
- Department of Nephrology, Transplant Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- Transplant Laboratory, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
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8
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Vasconcelos ADS, Mazzali M, de Sousa MV. IgA nephropathy and kidney transplantation according to the Oxford classification. J Bras Nefrol 2023; 45:350-356. [PMID: 36626310 PMCID: PMC10697166 DOI: 10.1590/2175-8239-jbn-2022-0051en] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 11/09/2022] [Indexed: 01/11/2023] Open
Abstract
INTRODUCTION IgA nephropathy (IgAN) is the most common glomerular disease globally, and its susceptibility and the risk for the development of end-stage kidney disease are related to genetic and environmental factors. IgAN recurrence after kidney transplantation is relatively common, impacting graft function and survival. This study evaluated the risk factors and the clinical, laboratory, and histological characteristics of post-transplant IgAN recurrence based on the Oxford classification. MATERIAL AND METHODS Retrospective single-center cohort study including kidney transplant recipients with biopsy-proven pre-transplantation IgAN, with analysis of risk factors and clinical, laboratory, and histological characteristics of the IgAN recurrence cases. RESULTS 53 patients fulfilled the inclusion criteria and were included in the study. The majority was male, white, eutrophic, with a mean age of 27 ± 9 years at IgAN diagnosis. Systemic arterial hypertension and proteinuria were frequent in the pretransplant period. Four recipients (7.5%) presented IgAN recurrence in a period of 6 to 122 months post-transplant. According to the Oxford classification, they had high scores of mesangial hypercellularity and segmental glomerulosclerosis in the native kidney biopsies and there was mesangial hypercellularity in all analyzed graft biopsies. None of these patients had received induction immunosuppression and all of them presented graft failure in the follow-up. CONCLUSIONS In this series, there was a high prevalence of mesangial hypercellularity and segmental glomerulosclerosis on native kidney biopsies, and mesangial hypercellularity occurred in all IgAN recurrence graft biopsies. Despite the lower incidence of recurrence of IgAN post-transplant compared to previous reports, progression to graft loss was of 100%.
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Affiliation(s)
- André de Sá Vasconcelos
- Universidade Estadual de Campinas, Faculdade de Ciências Médicas,
Departamento de Clínica Médica, Divisão de Nefrologia, Unidade de Transplante Renal,
Laboratório de Investigação em Transplante, Campinas, SP, Brasil
| | - Marilda Mazzali
- Universidade Estadual de Campinas, Faculdade de Ciências Médicas,
Departamento de Clínica Médica, Divisão de Nefrologia, Unidade de Transplante Renal,
Laboratório de Investigação em Transplante, Campinas, SP, Brasil
| | - Marcos Vinicius de Sousa
- Universidade Estadual de Campinas, Faculdade de Ciências Médicas,
Departamento de Clínica Médica, Divisão de Nefrologia, Unidade de Transplante Renal,
Laboratório de Investigação em Transplante, Campinas, SP, Brasil
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9
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Barratt J, Lafayette RA, Zhang H, Tesar V, Rovin BH, Tumlin JA, Reich HN, Floege J. IgA Nephropathy: the Lectin Pathway and Implications for Targeted Therapy. Kidney Int 2023:S0085-2538(23)00395-2. [PMID: 37263354 DOI: 10.1016/j.kint.2023.04.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 03/30/2023] [Accepted: 04/14/2023] [Indexed: 06/03/2023]
Abstract
Many patients with IgA nephropathy (IgAN) progress to end-stage kidney disease even with optimal supportive care. An improved understanding of the pathophysiology of IgAN in recent years has led to the investigation of targeted therapies with acceptable tolerability that may address the underlying causes of IgAN or the pathogenesis of kidney injury. The complement system - particularly the lectin and alternative pathways of complement - have emerged as key mediators of kidney injury in IgAN and possible targets for investigational therapy. This review will focus on the lectin pathway. Examination of kidney biopsies has consistently shown glomerular deposition of mannan-binding lectin (one of six pattern-recognition molecules that activate the lectin pathway) together with IgA1 in up to 50% of patients with IgAN. Glomerular deposition of pattern-recognition molecules for the lectin pathway is associated with more severe glomerular damage and more severe proteinuria and hematuria. Emerging research suggests that the lectin pathway may also contribute to tubulointerstitial fibrosis in IgAN, and that collectin-11 is a key mediator of this association. This review summarizes the growing scientific and clinical evidence supporting the role of the lectin pathway in IgAN and examines the possible therapeutic role of lectin pathway inhibition for these patients.
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Affiliation(s)
| | | | - Hong Zhang
- Peking University Institute of Nephrology, Beijing, China
| | - Vladimir Tesar
- Charles University and General University Hospital, Prague, Czech Republic
| | - Brad H Rovin
- The Ohio State University Wexner Medical Center, Columbus OH, USA
| | | | - Heather N Reich
- University of Toronto and University Health Network, Toronto ON, Canada
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10
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Wang D, Wu C, Chen S, Li Y, Wang L, Zhang Y, Li G. Urinary complement profile in IgA nephropathy and its correlation with the clinical and pathological characteristics. Front Immunol 2023; 14:1117995. [PMID: 37020564 PMCID: PMC10068869 DOI: 10.3389/fimmu.2023.1117995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 03/03/2023] [Indexed: 03/22/2023] Open
Abstract
Background and objectivesThe activated complement profile in IgA nephropathy (IgAN) is still unclear. Our study investigated the profile of urinary complements in IgAN patients and its correlations with clinical and pathological characteristics.MethodsUrinary protein abundance was detected by liquid chromatography-tandem mass spectrometry (LC–MS/MS) in 50 IgAN, 50 membranous nephropathy (MN), and 68 healthy controls (HC). Then, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to identify differentially expressed proteins in IgAN patients. The differentially expressed complement proteins were screened in IgAN patients, and their correlations with laboratory or pathological parameters were analyzed. Thereafter, 7 complement components were validated by enzyme-linked immunosorbent assay (ELISA) in the urine samples of 45 IgAN patients.ResultsThere were 786 differentially expressed proteins between IgAN and HC. KEGG analysis showed that differentially expressed urinary proteins in IgAN were enriched with complement. Of these, 67% of urinary complement protein abundance was associated with the estimated glomerular filtration rate. The urinary complement-related protein collectin12 (colec12), complement H factor (CFH), complement H factor-related protein 2 (CFHR2), and complement B factor (CFB) were positively correlated with serum creatinine; colec12, CFHR2, CFB, and C8g were positively correlated with glomerulosclerosis; CFH, CFHR2, C8g, and C9 were positively correlated with tubular atrophy/interstitial fibrosis.ConclusionAbnormally increased components of complement pathways significantly correlate with reduced renal function, proteinuria, and renal histological damage in IgAN. It could provide a potential biomarker panel for monitoring IgAN and provide clues for therapeutic choice targeting complement system of IgAN patients.
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Affiliation(s)
- Dongqing Wang
- Renal Department and Nephrology Institute, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Changwei Wu
- Renal Department and Nephrology Institute, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Sipei Chen
- Renal Department and Nephrology Institute, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Yi Li
- Renal Department and Nephrology Institute, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Li Wang
- Renal Department and Nephrology Institute, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Yong Zhang
- Institutes for Systems Genetics, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Guisen Li, ; Yong Zhang,
| | - Guisen Li
- Renal Department and Nephrology Institute, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
- *Correspondence: Guisen Li, ; Yong Zhang,
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11
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Vasconcelos ADS, Mazzali M, de Sousa MV. Nefropatia por IgA e transplante renal segundo a classificação de Oxford. J Bras Nefrol 2023. [DOI: 10.1590/2175-8239-jbn-2022-0051pt] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Resumo Introdução: Nefropatia por IgA (NIgA) é a doença glomerular mais comum mundialmente. Sua suscetibilidade e risco para desenvolvimento de doença renal em fase terminal estão relacionados a fatores genéticos e ambientais. A recidiva de NIgA pós-transplante é relativamente comum, impactando na função e sobrevida do enxerto. Este estudo avaliou fatores de risco e características clínicas, laboratoriais e histológicas da recidiva de NIgA pós-transplante, com base na classificação de Oxford. Material e métodos: Estudo de coorte retrospectivo de centro único, incluindo receptores de transplante renal com NIgA pré-transplante comprovada por biópsia, com análise dos fatores de risco e características clínicas, laboratoriais e histológicas dos casos de recidiva de NIgA. Resultados: 53 pacientes preencheram critérios de inclusão e foram incluídos no estudo. A maioria era homem, branco, eutrófico, com idade média de 27 ± 9 anos no diagnóstico de NIgA. Hipertensão arterial sistêmica e proteinúria foram frequentes no período pré-transplante. Quatro receptores (7,5%) apresentaram recidiva de NIgA entre 6-122 meses pós-transplante. Segundo a classificação de Oxford, eles apresentaram altos escores de hipercelularidade mesangial e glomeruloesclerose segmentar nas biópsias de rins nativos. Houve hipercelularidade mesangial em todas as biópsias de enxerto analisadas. Nenhum destes pacientes recebeu imunossupressão de indução. Todos apresentaram falência do enxerto no acompanhamento. Conclusões: Nesta série, houve alta prevalência de hipercelularidade mesangial e glomeruloesclerose segmentar em biópsias de rins nativos, e hipercelularidade mesangial ocorreu em todas as biópsias do enxerto de recidiva da NIgA. Apesar da menor incidência de recidiva de NIgA pós-transplante comparada a relatos anteriores, a progressão para perda do enxerto foi de 100%.
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Guo WY, An XP, Sun LJ, Dong HR, Cheng WR, Ye N, Wang GQ, Xu XY, Zhao ZR, Cheng H. Overactivation of the complement system may be involved in intrarenal arteriolar lesions in IgA nephropathy. Front Med (Lausanne) 2022; 9:945913. [PMID: 35991640 PMCID: PMC9381866 DOI: 10.3389/fmed.2022.945913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 07/18/2022] [Indexed: 11/13/2022] Open
Abstract
Introduction IgA nephropathy (IgAN) encompasses a wide range of clinical and histology features. Some patients present without hematuria, with or without hypertension, still rapidly progress in renal function. Renal pathology of this part of patients were predominant intrarenal arteriolar lesions, rarely presented glomerular proliferative lesions. We aim to investigate the clinical and pathological characteristics and prognosis of these IgAN patients and initially explore whether the abnormal activation of complement is involved in the intrarenal arteriolar lesions of IgAN. Methods A total of 866 patients with renal biopsy-proven IgAN diagnosed at Beijing Anzhen Hospital were recruited. IgAN patients without intrarenal arteriolar lesions and proliferative lesions were excluded (n = 115), the rest were divided into arteriolar lesions group (n = 202) and proliferative lesions group (n = 549). Among them, 255 patients were regularly followed up for at least 1 year. Renal biopsy tissues of 104 IgAN patients were stained for complement components by immunohistochemistry and immunofluorescence. Results Compared with proliferative lesions group, the arteriolar lesions group experienced high percentage of hypertension (p = 0.004), low percentage of gross hematuria (p = 0.001), microscopic hematuria (p < 0.001) and less initial proteinuria (p = 0.033). Renal survival between the two groups was not significantly different (p = 0.133). MBL, C4d, FH and FHR5, C3c, and MAC deposited on intrarenal arteriole in arteriolar lesions group. Compare with the proliferative lesion group, the arteriolar lesions group exhibited a higher intensity of C3c deposition on the intrarenal arterioles (p = 0.048). C3c and CD31 co-deposited on intrarenal arterioles area in patients with intrarenal arteriolar lesions. Conclusion Renal survival of the IgAN patients in arteriolar lesions group was not better than those in proliferative lesions group. Abnormal activation of complement may be involved in the pathogenesis of arteriolar damage through the injury of endothelial cells in this clinical phenotype of IgAN.
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Abstract
Thrombotic microangiopathy (TMA) refers to a condition caused by microvascular injury that includes thrombosis, hemolytic anemia, and thrombocytopenia. There are two classic TMAs, hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura, as well as an atypical HUS (aHUS). aHUS includes a broad spectrum of disorders with diverse etiologies and shares clinical manifestations with classic TMA; however, it frequently lacks typical clinical and laboratory findings. These traits can confuse clinicians and pathologists in terms of renal pathologic diagnosis, especially in cases where TMA is associated with other glomerulopathies or hypertensive renal disease. In this review, new paradigms for classifying TMA and the diversity of histopathologic changes including associated renal diseases are discussed. Renal biopsy is an important and useful diagnostic tool for diagnosing TMA and identifying TMA changes in other renal diseases, including hypertension. Adopting the term “TMA features” for TMA-like changes in glomerulus or artery/arteriole in addition to the pathological diagnosis of glomerulopathy would be informative to clinicians for a prompt diagnosis and treatment of aHUS.
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Affiliation(s)
- Yong-Jin Kim
- Department of Pathology, Kyungpook National University Hospital, Daegu, Republic of Korea
- Correspondence: Yong-Jin Kim Department of Pathology, Kyungpook National University Hospital, 130 Dongdeok-ro, Jung-gu, Daegu 41944, Republic of Korea. E-mail:
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Li J, Guo L, Shi S, Zhou X, Zhu L, Liu L, Lv J, Zhang H. The Role of Complement in Microangiopathic Lesions of IgA Nephropathy. Kidney Int Rep 2022; 7:1219-1228. [PMID: 35685318 PMCID: PMC9171706 DOI: 10.1016/j.ekir.2022.03.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 03/08/2022] [Accepted: 03/28/2022] [Indexed: 11/26/2022] Open
Abstract
Introduction Methods Results Conclusion
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Wang Z, Jiang Y, Chen P, Wang J, Zhang X, Huang B, Zhou X, Shi S, Liu L, Lv J, Zhang H. OUP accepted manuscript. Nephrol Dial Transplant 2022; 37:2119-2127. [PMID: 35104893 DOI: 10.1093/ndt/gfac024] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Zi Wang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Yuanyuan Jiang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Pei Chen
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Jinwei Wang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Xue Zhang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Bo Huang
- Department of Nephrology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xujie Zhou
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Sufang Shi
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Lijun Liu
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Jicheng Lv
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Hong Zhang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
- Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China
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Jiang Y, Zan J, Shi S, Hou W, Zhao W, Zhong X, Zhou X, Lv J, Zhang H. Glomerular C4d Deposition and Kidney Disease Progression in IgA Nephropathy: A Systematic Review and Meta-analysis. Kidney Med 2021; 3:1014-1021. [PMID: 34939010 PMCID: PMC8664744 DOI: 10.1016/j.xkme.2021.06.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Background Glomerular deposition of C4d is a widely used biomarker for activation of the lectin pathway in the complement system and is reported to be associated with kidney progression in immunoglobulin A nephropathy (IgAN). The aim of this study was to evaluate whether glomerular C4d deposition, as a new biomarker, improves the prediction of kidney prognosis in IgAN. Study Design Systematic review and meta-analysis. Setting & Population Patients with biopsy-proven primary IgAN without age limitations. Selection Criteria for Studies: Cross-sectional or cohort studies reporting the prevalence of glomerular C4d deposition or evaluating its association with IgAN progression. Predictor Glomerular C4d deposition. Outcome Composite progression event of a >30% decline in estimated glomerular filtration rate or end-stage kidney disease. Results 12 studies with 1,251 patients were included. The prevalence of glomerular C4d deposition was 34% (95% CI, 27%-41%), with large heterogeneity (I2 = 86%; P < 0.001). Patients with C4d deposition had lower estimated glomerular filtration rates (mean difference [MD], −11.48; 95% CI, −18.27 to −4.70; P < 0.001) as well as higher urinary protein-creatinine ratios (MD, 0.87; 95% CI, 0.53-1.21; P < 0.001) or 24-hour urinary protein excretion (MD, 0.99; 95% CI, 0.50-1.47; P < 0.001) and higher risk for hypertension (relative risk [RR], 1.45; 95% CI, 1.06-1.99; P = 0.02) than patients without C4d deposition. Glomerular C4d deposition was associated with a high Oxford classification score, including M1, E1, S1, and T1/2 lesions (all P ≤ 0.006). Patients with C4d deposition had higher rates of use of renin-angiotensin system blockers and immunosuppressants. Glomerular C4d was found to be a risk factor for the composite kidney event (RR, 3.17; 95% CI, 2.29-4.40; P < 0.001; adjusted HR, 2.05; 95% CI, 1.53-2.76; P < 0.001) and end-stage kidney disease (RR, 4.37; 95% CI, 3.15-6.07; P < 0.001) without evidence of heterogeneity. Limitations The definition of positive C4d was not uniform and not all studies provided data about kidney outcomes. Conclusions Glomerular C4d deposition is associated with an adverse prognosis and may be a useful biomarker of disease prediction in IgAN.
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Affiliation(s)
- Yuanyuan Jiang
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China.,Institute of Nephrology, Peking University, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China.,Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Jincan Zan
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China.,Institute of Nephrology, Peking University, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
| | - Sufang Shi
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China.,Institute of Nephrology, Peking University, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
| | - Wanyin Hou
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China.,Institute of Nephrology, Peking University, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
| | - Wenjing Zhao
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Xuhui Zhong
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China.,Institute of Nephrology, Peking University, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
| | - Xujie Zhou
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China.,Institute of Nephrology, Peking University, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
| | - Jicheng Lv
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China.,Institute of Nephrology, Peking University, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
| | - Hong Zhang
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China.,Institute of Nephrology, Peking University, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
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Poppelaars F, Faria B, Schwaeble W, Daha MR. The Contribution of Complement to the Pathogenesis of IgA Nephropathy: Are Complement-Targeted Therapies Moving from Rare Disorders to More Common Diseases? J Clin Med 2021; 10:4715. [PMID: 34682837 PMCID: PMC8539100 DOI: 10.3390/jcm10204715] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/05/2021] [Accepted: 10/06/2021] [Indexed: 12/29/2022] Open
Abstract
Primary IgA nephropathy (IgAN) is a leading cause of chronic kidney disease and kidney failure for which there is no disease-specific treatment. However, this could change, since novel therapeutic approaches are currently being assessed in clinical trials, including complement-targeting therapies. An improved understanding of the role of the lectin and the alternative pathway of complement in the pathophysiology of IgAN has led to the development of these treatment strategies. Recently, in a phase 2 trial, treatment with a blocking antibody against mannose-binding protein-associated serine protease 2 (MASP-2, a crucial enzyme of the lectin pathway) was suggested to have a potential benefit for IgAN. Now in a phase 3 study, this MASP-2 inhibitor for the treatment of IgAN could mark the start of a new era of complement therapeutics where common diseases can be treated with these drugs. The clinical development of complement inhibitors requires a better understanding by physicians of the biology of complement, the pathogenic role of complement in IgAN, and complement-targeted therapies. The purpose of this review is to provide an overview of the role of complement in IgAN, including the recent discovery of new mechanisms of complement activation and opportunities for complement inhibitors as the treatment of IgAN.
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Affiliation(s)
- Felix Poppelaars
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, 9700 AD Groningen, The Netherlands; (B.F.); (M.R.D.)
| | - Bernardo Faria
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, 9700 AD Groningen, The Netherlands; (B.F.); (M.R.D.)
- Nephrology and Infectious Disease R&D Group, INEB, Institute of Investigation and Innovation in Health (i3S), University of Porto, 4200-135 Porto, Portugal
| | - Wilhelm Schwaeble
- Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK;
| | - Mohamed R. Daha
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, 9700 AD Groningen, The Netherlands; (B.F.); (M.R.D.)
- Department of Nephrology, Leiden University Medical Center, University of Leiden, 2300 RC Leiden, The Netherlands
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Wu J, Hu Z, Wang Y, Hu D, Yang Q, Li Y, Dai W, Zhu F, Yang J, Wang M, Zhu H, Liu L, He X, Han M, Yao Y, Pei G, Zeng R, Xu G. Severe glomerular C3 deposition indicates severe renal lesions and a poor prognosis in patients with immunoglobulin A nephropathy. Histopathology 2021; 78:882-895. [PMID: 33336446 DOI: 10.1111/his.14318] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 11/23/2020] [Accepted: 12/16/2020] [Indexed: 01/04/2023]
Abstract
AIMS Glomerular complement 3 (C3) deposition is often observed in renal biopsies of patients with IgA nephropathy (IgAN); however, the relationship between the intensity of C3 deposition and the long-term prognosis of IgAN has rarely been reported. In this retrospective study, we aimed to evaluate the prognostic value of glomerular C3 deposition for IgAN progression. METHODS AND RESULTS From June 2009 to June 2010, a total of 136 adult patients with IgAN were enrolled in the study. According to the intensity of glomerular C3 deposition, patients were divided into a glomerular C3high group (34 patients) and a glomerular C3low group (102 patients). The levels of clinical parameters, glomerular immune complexes, histopathological features, and serum cytokines of the two groups were compared. On the basis of an average of 105 months of follow-up, the predictive value of glomerular C3 deposition for IgAN progression was also investigated. Patients in the C3high group had more severe glomerular IgA, IgG, IgM, and complement factor H deposition, a higher percentage of mesangial hypercellularity (M1), and higher levels of segmental glomerulosclerosis (S1), tubular atrophy/interstitial fibrosis (T2), and crescents (C2) than those in the C3low group. Renal biopsies in the C3high group showed higher densities of interstitial inflammatory cells and higher levels of serum interferon-γ than those in the C3low group. Multivariate Cox regression analysis revealed that a higher intensity of glomerular C3 deposition remained as an independent predictor of serum creatinine doubling and end-stage renal disease. CONCLUSIONS A high intensity of glomerular C3 deposition is associated with the severity of renal lesions, and predicts long-term poor renal survival for IgAN patients.
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Affiliation(s)
- Jianliang Wu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Zhizhi Hu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yuxi Wang
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Danni Hu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Qian Yang
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yueqiang Li
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Wei Dai
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Fengming Zhu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Juan Yang
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Meng Wang
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Han Zhu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Liu Liu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaofeng He
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Min Han
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Ying Yao
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Guangchang Pei
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Rui Zeng
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Gang Xu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
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Eder M, Kozakowski N, Omic H, Aigner C, Kläger J, Perschl B, Reindl-Schwaighofer R, Bond G, Böhmig GA, Kikić Ž. Glomerular C4d in Post-Transplant IgA Nephropathy is associated with decreased allograft survival. J Nephrol 2021; 34:839-49. [PMID: 33306182 DOI: 10.1007/s40620-020-00914-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 11/11/2020] [Indexed: 11/23/2022]
Abstract
Background Glomerulonephritis (GN), including post-transplant IgAN (post-Tx IgAN) is an important contributor to decreased long-term allograft survival. The immunopathological detection of the complement degradation product C4d in glomeruli (C4dG) has been recently described as a risk factor in native kidney IgAN, however little is known about C4dG deposition in post-Tx IgAN. We hypothesized that glomerular C4d may indicate a more aggressive disease course and worse allograft survival in patients with post-Tx IgAN. Methods In this retrospective study we assessed the presence and clinical relevance of C4dG in patients with post-transplant IgAN. We analyzed 885 renal allograft recipients, including 84 patients with post-transplant GN. All patients were transplanted between January 1999 and April 2006 and underwent at least one biopsy for differnt causes. The primary endpoint was death-censored graft survival, with a median follow-up of 9.6 (IQR 3.8–13.2) years. Results The prevalence of post-Tx GN was 9.5%. Twenty-seven patients with post-Tx IgAN were included. C4dG positive patients (N = 18, 66.7%) had significantly worse allograft survival compared to C4dG negative post-Tx IgAN patients and patients without post-Tx IgAN [C4dG positive: 27.8% vs. 55.6% and 66.0%; log-rank: p = 0.01]. C4dG remained a significant risk factor (HR 2.22, 95% CI 1.27–3.87) for allograft loss even after adjustment for T cell mediated rejection (TCMR) and antibody mediated rejection. Conclusion Glomerular C4d deposition is an independent risk factor for worse graft-survival in patients with post-Tx IgAN, even after adjusting for other risk factors such as antibody mediated rejection. Assessment of glomerular C4d deposition may provide a valuable prognostic risk assessment tool to identify high risk patients in post-Tx IgAN. Graphic abstract ![]()
Electronic supplementary material The online version of this article (10.1007/s40620-020-00914-x) contains supplementary material, which is available to authorized users.
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Poppelaars F, Thurman JM. Complement-mediated kidney diseases. Mol Immunol 2020; 128:175-87. [DOI: 10.1016/j.molimm.2020.10.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 09/16/2020] [Accepted: 10/19/2020] [Indexed: 12/19/2022]
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