1
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Vivarelli M, Barratt J, Beck LH, Fakhouri F, Gale DP, Goicoechea de Jorge E, Mosca M, Noris M, Pickering MC, Susztak K, Thurman JM, Cheung M, King JM, Jadoul M, Winkelmayer WC, Smith RJH. The role of complement in kidney disease: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference. Kidney Int 2024:S0085-2538(24)00389-2. [PMID: 38844295 DOI: 10.1016/j.kint.2024.05.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 04/25/2024] [Accepted: 05/22/2024] [Indexed: 06/22/2024]
Abstract
Uncontrolled complement activation can cause or contribute to glomerular injury in multiple kidney diseases. Although complement activation plays a causal role in atypical hemolytic uremic syndrome and C3 glomerulopathy, over the past decade, a rapidly accumulating body of evidence has shown a role for complement activation in multiple other kidney diseases, including diabetic nephropathy and several glomerulonephritides. The number of available complement inhibitor therapies has also increased during the same period. In 2022, Kidney Diseases: Improving Global Outcomes (KDIGO) convened a Controversies Conference, "The Role of Complement in Kidney Disease," to address the expanding role of complement dysregulation in the pathophysiology, diagnosis, and management of various glomerular diseases, diabetic nephropathy, and other forms of hemolytic uremic syndrome. Conference participants reviewed the evidence for complement playing a primary causal or secondary role in progression for several disease states and considered how evidence of complement involvement might inform management. Participating patients with various complement-mediated diseases and caregivers described concerns related to life planning, implications surrounding genetic testing, and the need for inclusive implementation of effective novel therapies into clinical practice. The value of biomarkers in monitoring disease course and the role of the glomerular microenvironment in complement response were examined, and key gaps in knowledge and research priorities were identified.
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Affiliation(s)
- Marina Vivarelli
- Laboratory of Nephrology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.
| | - Jonathan Barratt
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Laurence H Beck
- Section of Nephrology, Department of Medicine, Boston Medical Center Boston, Massachusetts, USA; Boston University Chobanian and Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Fadi Fakhouri
- Department of Nephrology, Centre Hospitalier Universitaire, Nantes, France; INSERM UMR S1064, Nantes, France
| | - Daniel P Gale
- Department of Renal Medicine, University College London, UK
| | - Elena Goicoechea de Jorge
- Department of Immunology, Ophthalmology and ORL, Complutense University, Madrid, Spain; Research Institute Hospital 12 de Octubre (imas12), Madrid, Spain
| | - Marta Mosca
- Department of Clinical and Experimental Medicine-Rheumatology Unit, University of Pisa, Pisa, Italy
| | - Marina Noris
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Ranica, Italy
| | - Matthew C Pickering
- Centre for Inflammatory Disease, Department of Immunology and Inflammation, Imperial College, Hammersmith Campus, London, UK
| | - Katalin Susztak
- Department of Medicine and Nephrology, Albert Einstein College Medicine, Bronx, New York, USA
| | - Joshua M Thurman
- Division of Nephrology and Hypertension, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | | | | | - Michel Jadoul
- Cliniques Universitaires Saint Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Wolfgang C Winkelmayer
- Selzman Institute for Kidney Health, Section of Nephrology, Department of Medicine, Baylor College of Medicine, Houston, Texas, USA
| | - Richard J H Smith
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA; Department of Internal Medicine, Division of Nephrology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA; Department of Pediatrics Division of Nephrology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.
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2
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Del Vecchio L, Allinovi M, Comolli S, Peiti S, Rimoldi C, Locatelli F. Drugs in Development to Treat IgA Nephropathy. Drugs 2024; 84:503-525. [PMID: 38777962 DOI: 10.1007/s40265-024-02036-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/22/2024] [Indexed: 05/25/2024]
Abstract
IgA nephropathy is a common glomerulonephritis consequent to the autoimmune response to aberrant glycosylated immunoglobulin (Ig) A antibodies. Although it has historically been considered a benign disease, it has since become clear that a substantial percentage of patients reach end-stage kidney failure over the years. Several therapeutic attempts have been proposed, with systemic steroids being the most prevalent, albeit burdened by possible serious adverse events. Thanks to the more in-depth knowledge of the pathogenesis of IgA nephropathy, new treatment targets have been identified and new drugs developed. In this narrative review, we summarise the molecules under clinical development for the treatment of IgA nephropathy. As a search strategy, we used PubMed, Google, ClinicalTrials.gov and abstracts from recent international congresses. TRF budesonide and sparsentan are the two molecules at a more advanced stage, just entering the market. Other promising agents are undergoing phase III clinical development. These include anti-APRIL and anti-BLyS/BAFF antibodies and some complement inhibitors. Other new possible strategies include spleen tyrosine kinase inhibitors, anti-CD40 ligands and anti-CD38 antibodies. In an era increasingly characterised by 'personalised medicine' and 'precision therapy' approaches and considering that the potential therapeutic armamentarium for IgA nephropathy will be very broad in the near future, the identification of biomarkers capable of helping the nephrologist to select the right drug for the right patient should be the focus of future studies.
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Affiliation(s)
| | - Marco Allinovi
- Nephrology, Dialysis and Transplantation Unit, Careggi University Hospital, Florence, Italy
| | - Stefania Comolli
- Department of Nephrology and Dialysis, ASST Sette Laghi, Varese, Italy
| | - Silvia Peiti
- Department of Nephrology and Dialysis, ASST Lariana, Como, Italy
| | | | - Francesco Locatelli
- Past Director of the Department of Nephrology and Dialysis, ASST Lecco, Lecco, Italy
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3
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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] [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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4
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Rajasekaran A, Green TJ, Renfrow MB, Julian BA, Novak J, Rizk DV. Current Understanding of Complement Proteins as Therapeutic Targets for the Treatment of Immunoglobulin A Nephropathy. Drugs 2023; 83:1475-1499. [PMID: 37747686 PMCID: PMC10807511 DOI: 10.1007/s40265-023-01940-2] [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] [Accepted: 09/04/2023] [Indexed: 09/26/2023]
Abstract
Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide and a frequent cause of kidney failure. Currently, the diagnosis necessitates a kidney biopsy, with routine immunofluorescence microscopy revealing IgA as the dominant or co-dominant immunoglobulin in the glomerular immuno-deposits, often with IgG and sometimes IgM or both. Complement protein C3 is observed in most cases. IgAN leads to kidney failure in 20-40% of patients within 20 years of diagnosis and reduces average life expectancy by about 10 years. There is increasing clinical, biochemical, and genetic evidence that the complement system plays a paramount role in the pathogenesis of IgAN. The presence of C3 in the kidney immuno-deposits differentiates the diagnosis of IgAN from subclinical glomerular mesangial IgA deposition. Markers of complement activation via the lectin and alternative pathways in kidney-biopsy specimens are associated with disease activity and are predictive of poor outcome. Levels of select complement proteins in the circulation have also been assessed in patients with IgAN and found to be of prognostic value. Ongoing genetic studies have identified at least 30 loci associated with IgAN. Genes within some of these loci encode complement-system regulating proteins that can interact with immune complexes. The growing appreciation for the central role of complement components in IgAN pathogenesis highlighted these pathways as potential treatment targets and sparked great interest in pharmacological agents targeting the complement cascade for the treatment of IgAN, as evidenced by the plethora of ongoing clinical trials.
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Affiliation(s)
- Arun Rajasekaran
- Division of Nephrology, Department of Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Todd J Green
- Department of Microbiology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Matthew B Renfrow
- Department of Biochemistry and Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Bruce A Julian
- Division of Nephrology, Department of Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jan Novak
- Department of Microbiology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Dana V Rizk
- Division of Nephrology, Department of Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
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Duval A, Olagne J, Obrecht A, Vargas GG, Perrin P, Moulin B, Frémeaux-Bacchi V, Caillard S. Eculizumab as a therapeutic approach for severe crescentic recurrence of immunoglobulin A nephropathy after kidney transplantation. Am J Transplant 2023; 23:1626-1630. [PMID: 37268295 DOI: 10.1016/j.ajt.2023.05.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 05/22/2023] [Accepted: 05/26/2023] [Indexed: 06/04/2023]
Abstract
Crescentic forms of immunoglobulin A nephropathy (IgAN) are rare but can be associated with rapid kidney failure and a high rate of end-stage renal disease despite immunosuppression therapy. Complement activation has emerged as a key driver of glomerular injury in IgAN. Therefore, complement inhibitors may be a rational treatment option in patients unresponsive to first-line immunosuppressive therapy. Here, we describe the case of a 24-year-old woman presenting with crescentic IgAN recurrence a few months after living kidney transplantation. Considering the dramatic graft failure accompanied by malignant hypertension and thrombotic microangiopathy features worsening after a first-line of high-dose steroids and 3 sessions of plasma exchanges, eculizumab was started as a rescue therapy. For the first time, the clinical response to eculizumab was highly successful, with a complete graft recovery without any relapse after 1 year of treatment. Further clinical studies are strongly needed to specify which patients might benefit from terminal complement blockade.
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Affiliation(s)
- Anna Duval
- Department of nephrology, dialysis and transplantation, University Hospital of Strasbourg, Strasbourg, Bas Rhin, France; Inserm UMRS 1109 Molecular Immuno Rheumatology, University of Strasbourg, Strasbourg, Bas Rhin, France; Inserm UMRS 1138, Complement and diseases, Cordeliers' research center, Paris, France.
| | - Jérôme Olagne
- Department of nephrology, dialysis and transplantation, University Hospital of Strasbourg, Strasbourg, Bas Rhin, France; Department of pathology, University Hospital of Strasbourg, Strasbourg, Bas Rhin, France
| | - Augustin Obrecht
- Department of nephrology, dialysis and transplantation, University Hospital of Strasbourg, Strasbourg, Bas Rhin, France
| | - Gabriela Gautier Vargas
- Department of nephrology, dialysis and transplantation, University Hospital of Strasbourg, Strasbourg, Bas Rhin, France
| | - Peggy Perrin
- Department of nephrology, dialysis and transplantation, University Hospital of Strasbourg, Strasbourg, Bas Rhin, France
| | - Bruno Moulin
- Department of nephrology, dialysis and transplantation, University Hospital of Strasbourg, Strasbourg, Bas Rhin, France; Inserm UMRS 1109 Molecular Immuno Rheumatology, University of Strasbourg, Strasbourg, Bas Rhin, France
| | - Véronique Frémeaux-Bacchi
- Inserm UMRS 1138, Complement and diseases, Cordeliers' research center, Paris, France; Service d'immunologie Biologique, Hôpital Européen Georges Pompidou, Assistance publique des Hôpitaux de Paris, Paris, France
| | - Sophie Caillard
- Department of nephrology, dialysis and transplantation, University Hospital of Strasbourg, Strasbourg, Bas Rhin, France; Inserm UMRS 1109 Molecular Immuno Rheumatology, University of Strasbourg, Strasbourg, Bas Rhin, France
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6
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Tesař V, Radhakrishnan J, Charu V, Barratt J. Challenges in IgA Nephropathy Management: An Era of Complement Inhibition. Kidney Int Rep 2023; 8:1730-1740. [PMID: 37705895 PMCID: PMC10496078 DOI: 10.1016/j.ekir.2023.06.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/01/2023] [Accepted: 06/12/2023] [Indexed: 09/15/2023] Open
Abstract
IgA nephropathy (IgAN) is the most common glomerular disease worldwide, with an estimated annual incidence of 25 per million adults. Despite optimized supportive care, some patients fail to achieve disease control and suffer progressive deterioration of kidney function. In this subpopulation of patients, the Kidney Disease: Improving Global Outcomes 2021 guidelines recommend consideration of corticosteroids; however, their use is associated with significant side effects. Ongoing clinical trials are expected to identify corticosteroid-sparing therapies to help improve treatment and prognosis for patients with IgAN. It has been well-documented that the complement system plays a significant role in IgAN pathogenesis, and several complement inhibitors are now entering late-stage clinical development. This review evaluates what we know about the role of complement in the pathophysiology of IgAN and considers how the availability of targeted complement inhibitors may impact future clinical practice. Key knowledge gaps are evaluated, and research opportunities are recommended to help guide clinical decision-making and optimize patient outcomes. Such gaps include evaluating the relative contribution of the alternative and lectin pathways to disease pathogenesis, and the importance of determining the dominant pathway driving IgAN progression. Continued research into the staining of complement proteins in kidney biopsies and identifying targeted biomarkers to assess disease progression and treatment responses will also be needed to support the implementation of newer therapies in clinical practice. Considering the future horizons for enhancing the care of patients with IgAN, tackling the outstanding challenges now will help prepare for the best possible future outcomes.
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Affiliation(s)
- Vladimir Tesař
- Department of Nephrology, Charles University, Prague, Czech Republic
| | | | - Vivek Charu
- Department of Pathology, Stanford University, Palo Alto, California, USA
| | - Jonathan Barratt
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
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7
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Cheung CK, Dormer JP, Barratt J. The role of complement in glomerulonephritis-are novel therapies ready for prime time? Nephrol Dial Transplant 2023; 38:1789-1797. [PMID: 36307926 DOI: 10.1093/ndt/gfac296] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Indexed: 08/01/2023] Open
Abstract
The complement system plays a key pathogenic role in glomerular diseases with a diverse range of aetiologies, including C3 glomerulopathy, immunoglobulin A nephropathy, membranous nephropathy, ANCA-associated vasculitis and lupus nephritis. Several novel therapies targeting complement activity have recently been developed, which have now been approved or are in the late stages of clinical development. In this review, potential benefits and challenges of targeting the complement system in glomerular disease are discussed. We summarize current understanding of the role of complement, and the novel targeted therapies that are being developed for the treatment of glomerular disease.
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Affiliation(s)
- Chee Kay Cheung
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- John Walls Renal Unit, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - John P Dormer
- Department of Histopathology, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Jonathan Barratt
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- John Walls Renal Unit, University Hospitals of Leicester NHS Trust, Leicester, UK
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8
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Guo Y, Zhang H, Yu X. A bibliometric analysis of complement in IgA nephropathy from 1991 to 2022. Front Pharmacol 2023; 14:1200193. [PMID: 37576817 PMCID: PMC10414182 DOI: 10.3389/fphar.2023.1200193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 07/17/2023] [Indexed: 08/15/2023] Open
Abstract
Introduction: IgA nephropathy is a common glomerular disease on a global scale, which has resulted in significant economic burdens. The complement system plays a vital role in enhancing the efficacy of antibodies and phagocytic cells in eliminating microbes and damaged cells, and promoting inflammation. Complement activation has been found to contribute to the progression of various renal diseases, including IgA nephropathy. Methods: In this study, a thorough analysis was conducted on publications related to complement in IgAN from 1991 to 2022, retrieved from the Web of Science Core Collection and Scopus database. The analysis focused on various aspects such as annual publications, country, institution, author, journal, keywords, and co-cited references, utilizing Citespace and Vosviewer. Results: A total of 819 publications were obtained, and while there were slight fluctuations in annual publications, an overall upward trend was observed. China, Japan and the United States were the leading countries in terms of publications, with China having the highest number of publications (201). Collaborative network analysis revealed that England, University of Alabama Birmingham, and Robert J Wyatt were the most influential country, institution, and author, respectively, in this field of research. Furthermore, the analysis of references and keywords indicated that complement activation contributes to IgAN, and immunosuppression in IgAN are a hot topic of research. Discussion: This study identifies current research hotspots and advanced tendencies in the study of complement in IgAN, providing scholars with crucial directions in this research area.
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Affiliation(s)
- Yun Guo
- The First Clinical Medical College, Guangdong Medical University, Zhanjiang, China
- Department of Nephrology, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
| | | | - Xueqing Yu
- The First Clinical Medical College, Guangdong Medical University, Zhanjiang, China
- Department of Nephrology, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
- Guangdong-Hong Kong Joint Laboratory on Immunological and Genetic Kidney Diseases, Guangzhou, China
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9
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Gentile M, Sanchez-Russo L, Riella LV, Verlato A, Manrique J, Granata S, Fiaccadori E, Pesce F, Zaza G, Cravedi P. Immune abnormalities in IgA nephropathy. Clin Kidney J 2023; 16:1059-1070. [PMID: 37398689 PMCID: PMC10310525 DOI: 10.1093/ckj/sfad025] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Indexed: 09/10/2023] Open
Abstract
Immunoglobulin A (IgA) nephropathy (IgAN) is the most common primary glomerulonephritis worldwide and it is characterized by mesangial IgA deposition. Asymptomatic hematuria with various degrees of proteinuria is the most common clinical presentation and up to 20%-40% of patients develop end-stage kidney disease within 20 years after disease onset. The pathogenesis of IgAN involves four sequential processes known as the "four-hit hypothesis" which starts with the production of a galactose-deficient IgA1 (gd-IgA1), followed by the formation of anti-gd-IgA1 IgG or IgA1 autoantibodies and immune complexes that ultimately deposit in the glomerular mesangium, leading to inflammation and injury. Although several key questions about the production of gd-IgA1 and the formation of anti-gd-IgA1 antibodies remain unanswered, a growing body of evidence is shedding light on the innate and adaptive immune mechanisms involved in this complex pathogenic process. Herein, we will focus on these mechanisms that, along with genetic and environmental factors, are thought to play a key role in disease pathogenesis.
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Affiliation(s)
- Micaela Gentile
- Translational Transplant Research Center and Department of Medicine, Icahn School of Medicine at Mount Sinai, NY, USA
- UO Nefrologia, Dipartimento di Medicina e Chirurgia, Università di Parma, Parma, Italy
| | - Luis Sanchez-Russo
- Translational Transplant Research Center and Department of Medicine, Icahn School of Medicine at Mount Sinai, NY, USA
| | - Leonardo V Riella
- Division of Nephrology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Alberto Verlato
- Translational Transplant Research Center and Department of Medicine, Icahn School of Medicine at Mount Sinai, NY, USA
| | - Joaquin Manrique
- Nephrology Service, Complejo Hospitalario de Navarra, Pamplona, Spain
| | - Simona Granata
- Nephrology, Dialysis and Transplantation Unit, University of Foggia, Foggia, Italy
| | - Enrico Fiaccadori
- UO Nefrologia, Dipartimento di Medicina e Chirurgia, Università di Parma, Parma, Italy
| | - Francesco Pesce
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari “A. Moro”, Bari, Italy
| | - Gianluigi Zaza
- Nephrology, Dialysis and Transplantation Unit, University of Foggia, Foggia, Italy
| | - Paolo Cravedi
- Translational Transplant Research Center and Department of Medicine, Icahn School of Medicine at Mount Sinai, NY, USA
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Nguyen B, Acharya C, Tangpanithandee S, Miao J, Krisanapan P, Thongprayoon C, Amir O, Mao MA, Cheungpasitporn W, Acharya PC. Efficacy and Safety of Plasma Exchange as an Adjunctive Therapy for Rapidly Progressive IgA Nephropathy and Henoch-Schönlein Purpura Nephritis: A Systematic Review. Int J Mol Sci 2023; 24:ijms24043977. [PMID: 36835388 PMCID: PMC9958587 DOI: 10.3390/ijms24043977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/09/2023] [Accepted: 02/13/2023] [Indexed: 02/18/2023] Open
Abstract
Patients with IgA nephropathy (IgAN), including Henoch-Schönlein purpura nephritis (HSP), who present with rapidly progressive glomerulonephritis (RPGN) have a poor prognosis despite aggressive immunosuppressive therapy. The utility of plasmapheresis/plasma exchange (PLEX) for IgAN/HSP is not well established. This systematic review aims to assess the efficacy of PLEX for IgAN and HSP patients with RPGN. A literature search was conducted using MEDLINE, EMBASE, and through Cochrane Database from inception through September 2022. Studies that reported outcomes of PLEX in IgAN or HSP patients with RPGN were enrolled. The protocol for this systematic review is registered with PROSPERO (no. CRD42022356411). The researchers systematically reviewed 38 articles (29 case reports and 9 case series articles) with a total of 102 RPGN patients (64 (62.8%) had IgAN and 38 (37.2%) had HSP). The mean age was 25 years and 69% were males. There was no specific PLEX regimen utilized in these studies, but most patients received at least 3 PLEX sessions that were titrated based on the patient's response/kidney recovery. The number of PLEX sessions ranged from 3 to 18, and patients additionally received steroids and immunosuppressive treatment (61.6% of patients received cyclophosphamide). Follow-up time ranged from 1 to 120 months, with the majority being followed for at least 2 months after PLEX. Among IgAN patients treated with PLEX, 42.1% (n = 27/64) achieved remission; 20.3% (n = 13/64) achieved complete remission (CR) and 18.7% (n = 12/64) partial remission (PR). 60.9% (n = 39/64) progressed to end-stage kidney disease (ESKD). Among HSP patients treated with PLEX, 76.3% (n = 29/38) achieved remission; of these, 68.4% (n = 26/38) achieved CR and 7.8% achieved (n = 3/38) PR. 23.6% (n = 9/38) progressed to ESKD. Among kidney transplant patients, 20% (n = 1/5) achieved remission and 80% (n = 4/5) progressed to ESKD. Adjunctive plasmapheresis/plasma exchange with immunosuppressive therapy showed benefits in some HSP patients with RPGN and possible benefits in IgAN patients with RPGN. Future prospective, multi-center, randomized clinical studies are needed to corroborate this systematic review's findings.
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Affiliation(s)
- Bryan Nguyen
- Division of Nephrology, Texas Tech Health Sciences Center El Paso, El Paso, TX 79905, USA
| | - Chirag Acharya
- Division of Nephrology, Texas Tech Health Sciences Center El Paso, El Paso, TX 79905, USA
| | - Supawit Tangpanithandee
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Jing Miao
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Pajaree Krisanapan
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Division of Nephrology, Department of Internal Medicine, Thammasat University, Pathum Thani 12120, Thailand
| | - Charat Thongprayoon
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Omar Amir
- Division of Nephrology, Texas Tech Health Sciences Center El Paso, El Paso, TX 79905, USA
| | - Michael A. Mao
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Wisit Cheungpasitporn
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Correspondence:
| | - Prakrati C. Acharya
- Division of Nephrology, Texas Tech Health Sciences Center El Paso, El Paso, TX 79905, USA
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11
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Lausecker F, Koehler S, Fresquet M, Naylor RW, Tian P, Wanner N, Braun F, Butt L, Huber TB, Lennon R. Integrating basic science with translational research: the 13th International Podocyte Conference 2021. Kidney Int 2022; 102:708-719. [PMID: 35964799 PMCID: PMC9386279 DOI: 10.1016/j.kint.2022.07.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 07/20/2022] [Accepted: 07/26/2022] [Indexed: 11/30/2022]
Abstract
The 13th International Podocyte Conference was held in Manchester, UK, and online from July 28 to 30, 2021. Originally planned for 2020, this biannual meeting was postponed by a year because of the coronavirus disease 2019 (COVID-19) pandemic and proceeded as an innovative hybrid meeting. In addition to in-person attendance, online registration was offered, and this attracted 490 conference registrations in total. As a Podocyte Conference first, a day for early-career researchers was introduced. This premeeting included talks from graduate students and postdoctoral researchers. It gave early career researchers the opportunity to ask a panel, comprising academic leaders and journal editors, about career pathways and the future for podocyte research. The main meeting over 3 days included a keynote talk and 4 focused sessions each day incorporating invited talks, followed by selected abstract presentations, and an open panel discussion. The conference concluded with a Patient Day, which brought together patients, clinicians, researchers, and industry representatives. The Patient Day was an interactive and diverse day. As well as updates on improving diagnosis and potential new therapies, the Patient Day included a PodoArt competition, exercise and cooking classes with practical nutrition advice, and inspirational stories from patients and family members. This review summarizes the exciting science presented during the 13th International Podocyte Conference and demonstrates the resilience of researchers during a global pandemic.
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Affiliation(s)
- Franziska Lausecker
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Sybille Koehler
- Biomedical Sciences, University of Edinburgh, Edinburgh, UK; III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Maryline Fresquet
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Richard W Naylor
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Pinyuan Tian
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Nicola Wanner
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fabian Braun
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Linus Butt
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Tobias B Huber
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Rachel Lennon
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK; Department of Paediatric Nephrology, Royal Manchester Children's Hospital, Manchester University Hospitals National Health Service (NHS) Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK.
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12
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Freiwald T, Afzali B. Renal diseases and the role of complement: Linking complement to immune effector pathways and therapeutics. Adv Immunol 2021; 152:1-81. [PMID: 34844708 PMCID: PMC8905641 DOI: 10.1016/bs.ai.2021.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The complement system is an ancient and phylogenetically conserved key danger sensing system that is critical for host defense against pathogens. Activation of the complement system is a vital component of innate immunity required for the detection and removal of pathogens. It is also a central orchestrator of adaptive immune responses and a constituent of normal tissue homeostasis. Once complement activation occurs, this system deposits indiscriminately on any cell surface in the vicinity and has the potential to cause unwanted and excessive tissue injury. Deposition of complement components is recognized as a hallmark of a variety of kidney diseases, where it is indeed associated with damage to the self. The provenance and the pathophysiological role(s) played by complement in each kidney disease is not fully understood. However, in recent years there has been a renaissance in the study of complement, with greater appreciation of its intracellular roles as a cell-intrinsic system and its interplay with immune effector pathways. This has been paired with a profusion of novel therapeutic agents antagonizing complement components, including approved inhibitors against complement components (C)1, C3, C5 and C5aR1. A number of clinical trials have investigated the use of these more targeted approaches for the management of kidney diseases. In this review we present and summarize the evidence for the roles of complement in kidney diseases and discuss the available clinical evidence for complement inhibition.
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Affiliation(s)
- Tilo Freiwald
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Bethesda, MD, United States; Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany
| | - Behdad Afzali
- Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany.
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13
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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] [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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14
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Is complement the main accomplice in IgA nephropathy? From initial observations to potential complement-targeted therapies. Mol Immunol 2021; 140:1-11. [PMID: 34601376 DOI: 10.1016/j.molimm.2021.09.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 09/01/2021] [Accepted: 09/17/2021] [Indexed: 12/22/2022]
Abstract
IgA Nephropathy (IgAN) is the main cause of primary glomerulonephritis, globally. This disease is associated with a wide range of clinical presentations, variable prognosis and a spectrum of histological findings. More than fifty years after its first description, this heterogeneity continues to complicate efforts to understand the pathogenesis. Nevertheless, involvement of the complement system in IgAN was identified early on. Dysfunction of the immunoglobulin A (IgA) system, the principal offender in this disease, including modification of isoforms and glycoforms of IgA1, the nature of immune complexes and autoantibodies to galactose deficient IgA1 might all be responsible for complement activation in IgAN. However, the specific mechanisms engaging complement are still under examination. Research in this domain should allow for identification of patients that may benefit from complement-targeted therapy, in the foreseeable future.
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15
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Medjeral-Thomas NR, Cook HT, Pickering MC. Complement activation in IgA nephropathy. Semin Immunopathol 2021; 43:679-690. [PMID: 34379175 PMCID: PMC8551128 DOI: 10.1007/s00281-021-00882-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 07/23/2021] [Indexed: 11/25/2022]
Abstract
IgA nephropathy pathogenesis is incompletely understood, and this limits the development of disease-specific biomarkers and effective therapies. Evidence of complement activity in IgA nephropathy is well established. However, a growing body of research indicates complement activity is an important contributor to IgA nephropathy pathology. In particular, multiple associations have been identified between complement alternative, lectin and terminal pathway proteins and IgA nephropathy severity. Recently, we have also gained insight into possible mechanisms that could link glomerular IgA deposition, complement activity, glomerular inflammation and disease severity. Ongoing clinical trials of therapeutic complement inhibitors will provide insight into the importance of complement activity to IgA nephropathy pathogenesis. Further research into mechanisms of complement activity is essential to improving our understanding and management of patients with IgA nephropathy.
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Affiliation(s)
- Nicholas R Medjeral-Thomas
- Centre for Inflammatory Disease, Department of Immunology and Inflammation, Imperial College London, London, W12 0NN, UK.
| | - H Terence Cook
- Centre for Inflammatory Disease, Department of Immunology and Inflammation, Imperial College London, London, W12 0NN, UK
| | - Matthew C Pickering
- Centre for Inflammatory Disease, Department of Immunology and Inflammation, Imperial College London, London, W12 0NN, UK
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16
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An Update on the Current State of Management and Clinical Trials for IgA Nephropathy. J Clin Med 2021; 10:jcm10112493. [PMID: 34200024 PMCID: PMC8200196 DOI: 10.3390/jcm10112493] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 12/31/2022] Open
Abstract
IgA nephropathy remains the most common primary glomerular disease worldwide. It affects children and adults of all ages, and is a leading cause of end-stage kidney disease, making it a considerable public health issue in many countries. Despite being initially described over 50 years ago, there are still no disease specific treatments, with current management for most patients being focused on lifestyle measures and renin-angiotensin-aldosterone system blockade. However, significant advances in the understanding of its pathogenesis have been made particularly over the past decade, leading to great interest in developing new therapeutic strategies, and a significant rise in the number of interventional clinical trials being performed. In this review, we will summarise the current state of management of IgAN, and then describe major areas of interest where new therapies are at their most advanced stages of development, that include the gut mucosal immune system, B cell signalling, the complement system and non-immune modulators. Finally, we describe clinical trials that are taking place in each area and explore future directions for translational research.
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17
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Wu D, Li X, Yao X, Zhang N, Lei L, Zhang H, Tang M, Ni J, Ling C, Chen Z, Chen X, Liu X. Mesangial C3 deposition and serum C3 levels predict renal outcome in IgA nephropathy. Clin Exp Nephrol 2021; 25:641-651. [PMID: 33620604 DOI: 10.1007/s10157-021-02034-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 02/12/2021] [Indexed: 12/26/2022]
Abstract
BACKGROUND Complement activation plays an important role in the pathogenesis of IgA nephropathy (IgAN). We aimed to evaluate the relationship between mesangial C3 deposition and histologic lesions and to investigate the role of mesangial C3 deposition and serum C3 reduction in predicting renal outcome in IgAN children. METHODS We performed a retrospective cohort study in children with biopsy-proven IgAN. Mesangial C3 deposition (< 2+ vs. ≥ 2+) was detected by the immunofluorescence. Histopathologic kidney grades were determined by the Oxford classification. A decreased serum C3 concentration (hypoC3) was defined when C3 < 90 mg/dl. The endpoint was composite kidney outcome with either a 30% decline in glomerular filtration rates from baseline or kidney failure during the follow-up period. RESULTS A total of 98 children were analyzed. Mesangial hypercellularity (M) was an independent factor associated with mesangial C3 deposition (HR 3.267; 95% CI 1.028-10.389; P = 0.045). After a median follow-up period of 25 months (interquartile range 18-36 months), 6 (6.1%) children reached the endpoint. Compared with other children, a significantly higher proportion of children with composite kidney outcomes had mesangial C3 deposition ≥ 2+ and hypoC3 (3.4% versus 27.3%, P = 0.002). After adjustment for clinicopathologic risk factors, mesangial C3 deposition ≥ 2+ and hypoC3 were associated with renal outcome (HR 9.772; 95% CI 1.264-75.518; P = 0.029). CONCLUSION Mesangial C3 deposition was associated with M in IgAN. Mesangial C3 deposition and hypoC3 were risk factors for renal outcome in children with IgAN.
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Affiliation(s)
- Dan Wu
- Department of Nephrology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Xueqian Li
- Department of Nephrology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Xingfeng Yao
- Department of Pathology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Nan Zhang
- Department of Pathology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Lei Lei
- Department of Nephrology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Hejia Zhang
- Department of Nephrology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Mengmeng Tang
- Department of Nephrology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Jie Ni
- Department of Nephrology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Chen Ling
- Department of Nephrology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Zhi Chen
- Department of Nephrology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China
| | - Xiangmei Chen
- Department of Nephrology, State Key Laboratory of Kidney Diseases, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, National Clinical Research Center for Kidney Diseases, 28th Fuxing Road, Beijing, 100853, China
| | - Xiaorong Liu
- Department of Nephrology, Beijing Children's Hospital, Capital Medical University, Beijing, 100045, China.
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18
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Dumont C, Mérouani A, Ducruet T, Benoit G, Clermont MJ, Lapeyraque AL, Phan V, Patey N. Clinical relevance of membrane attack complex deposition in children with IgA nephropathy and Henoch-Schönlein purpura. Pediatr Nephrol 2020; 35:843-850. [PMID: 31932958 DOI: 10.1007/s00467-019-04445-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 11/26/2019] [Accepted: 12/03/2019] [Indexed: 11/26/2022]
Abstract
BACKGROUND IgA nephropathy (IgAN) and Henoch-Schönlein purpura are common glomerular disorders in children sharing the same histopathologic pattern of IgA deposits within the mesangium, even if their physiopathology may be different. Repeated exposure to pathogens induces the production of abnormal IgA1. The immune complex deposition in the renal mesangium in IgAN or potentially in small vessels in Henoch-Schönlein purpura induces complement activation via the alternative and lectin pathways. Recent studies suggest that levels of membrane attack complex (MAC) in the urine might be a useful indicator of renal injury. Because of the emerging availability of therapies that selectively block complement activation, the aim of the present study is to investigate whether MAC immunostaining might be a useful marker of IgA-mediated renal injury. METHODS We conducted immunohistochemistry analysis of the MAC on renal biopsies from 67 pediatric patients with IgAN and Henoch-Schönlein purpura. We classified their renal biopsies according to the Oxford classification, retrieved symptoms, biological parameters, treatment, and follow-up. RESULTS We found MAC expression was significantly related to impaired renal function and patients whose clinical course required therapy. MAC deposits tend to be more abundant in patients with decreased glomerular filtration rate (p = 0.02), patients with proteinuria > 0.750 g/day/1.73 m2, and with nephrotic syndrome. No correlation with histological alterations was observed. CONCLUSIONS We conclude that MAC deposition could be a useful additional indicator of renal injury in patients with IgAN and Henoch-Schönlein purpura, independent of other indicators.
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Affiliation(s)
- Camille Dumont
- Department of Pathology, CHU Sainte Justine, 3175 Chemin Côte Sainte Catherine, Montréal, Québec, H3T 1C5, Canada
| | - Aicha Mérouani
- Department of Nephrology, CHU Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
| | - Thierry Ducruet
- Applied Clinical Research Unit, CHU Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
| | - Geneviève Benoit
- Department of Nephrology, CHU Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
| | - Marie-Josée Clermont
- Department of Nephrology, CHU Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
| | - Anne Laure Lapeyraque
- Department of Nephrology, CHU Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
| | - Véronique Phan
- Department of Nephrology, CHU Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
| | - Natalie Patey
- Department of Pathology, CHU Sainte Justine, 3175 Chemin Côte Sainte Catherine, Montréal, Québec, H3T 1C5, Canada.
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Complement activation is associated with crescent formation in IgA nephropathy. Virchows Arch 2020; 477:565-572. [PMID: 32300880 DOI: 10.1007/s00428-020-02800-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 03/11/2020] [Accepted: 03/18/2020] [Indexed: 12/21/2022]
Abstract
IgA nephropathy (IgAN) is common chronic glomerulonephritis with variable prognosis, ranging from minor urinary abnormalities to end-stage renal disease. The revised Oxford classification of IgAN explains that cellular/fibrocellular crescents are associated with poor renal prognosis, proposing an extension to the MEST-C score. C3 immunofluorescent staining follows a distribution similar to IgA staining. Therefore, complement activation was reported to play a pivotal role in IgAN pathogenesis. This study included 132 IgAN patients diagnosed by renal biopsies. The clinical parameters at the time of the biopsies were obtained from patient data records. We classified the patients into C ≥ 1 and C0 groups, and compared clinical, light microscopic, and immunofluorescent features. In the C ≥ 1 group, 2 (1.5%) and 31 (23.5%) patients were assigned to C2 and C1, respectively. The remaining 99 patients (75%) were classified as C0. The C ≥ 1 group had lower average age and rate of hypertension, and higher score of urinary occult blood and E score. The C ≥ 1 group had significantly higher average immunofluorescence scores for IgA, C5b-9, mannose-associated serine protease (MASP) 1/3, MASP2, properdin, factor B, and kappa. The steroid use rate was significantly higher in the C ≥ 1 group. During the follow-up period of 2.90 years on average, the rate of renal dysfunction was not significantly different between groups. Crescent formation in IgAN was associated with activation of the lectin and alternative pathways. The C ≥ 1 group had significantly increased use of steroids, which probably caused comparable renal function during the follow-up period.
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20
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Medjeral-Thomas NR, O'Shaughnessy MM. Complement in IgA Nephropathy: The Role of Complement in the Pathogenesis, Diagnosis, and Future Management of IgA Nephropathy. Adv Chronic Kidney Dis 2020; 27:111-119. [PMID: 32553243 DOI: 10.1053/j.ackd.2019.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 12/12/2022]
Abstract
Immunoglobulin A (IgA) nephropathy (IgAN) is an important cause of chronic and end-stage kidney disease. IgAN pathogenesis is incompletely understood. In particular, we cannot adequately explain the heterogeneity in clinical and histologic features and severities that characterizes IgAN. This limits patient stratification to appropriate and effective treatments and the development of disease-targeted therapies. Studies of the role of the alternative, lectin, and terminal complement pathways in IgAN have enhanced our understanding of disease pathogenesis and inform the development of novel diagnostic and therapeutic strategies. For example, recent genetic, serologic, and immunohistologic evidence suggests that imbalances between the main alternative complement pathway regulator protein (factor H) and competitor proteins that deregulate complement activity (factor H-related proteins 1 and 5, FHR1, and FHR5) associate with IgAN severity: a relative abundance of FHR1 and FHR5 amplifies complement-dependent inflammation and exacerbates kidney injury. Ongoing characterization of the mechanisms by which complement activity contributes to IgAN pathogenesis will facilitate the development of complement-based diagnostic techniques, biomarkers of disease activity and severity, and novel targeted therapies.
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21
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Tortajada A, Gutierrez E, Pickering MC, Praga Terente M, Medjeral-Thomas N. The role of complement in IgA nephropathy. Mol Immunol 2019; 114:123-132. [PMID: 31351413 DOI: 10.1016/j.molimm.2019.07.017] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 07/16/2019] [Accepted: 07/16/2019] [Indexed: 12/22/2022]
Abstract
IgA nephropathy (IgAN) is common and often progresses to end stage renal disease. IgAN encompasses a wide range of histology and clinical features. IgAN pathogenesis is incompletely understood; the current multi-hit hypothesis of IgAN pathogenesis does not explain the range of glomerular inflammation and renal injury associated with mesangial IgA deposition. Although associations between IgAN and glomerular and circulating markers of complement activation are established, the mechanism of complement activation and contribution to glomerular inflammation and injury are not defined. Recent identification of specific complement pathways and proteins in severe IgAN cases had advanced our understanding of complement in IgAN pathogenesis. In particular, a growing body of evidence implicates the complement factor H related proteins 1 and 5 and lectin pathway as pathogenic in a subset of patients with severe disease. These data suggest complement deregulation and activity may be dominant drivers of renal injury in IgAN. Thereby, markers of complement activation may identify IgAN patients likely to progress to significant renal impairment and complement inhibition may emerge as an effective method of preventing and reducing glomerular injury in IgAN.
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Affiliation(s)
- Agustin Tortajada
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Eduardo Gutierrez
- Department of Nephrology, Research Institute Universitary Hospital 12 de Octubre (imas12), Madrid, Spain
| | | | - Manuel Praga Terente
- Department of Nephrology, Research Institute Universitary Hospital 12 de Octubre (imas12), Madrid, Spain
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Complement-mediated microangiopathy in IgA nephropathy and IgA vasculitis with nephritis. Mod Pathol 2019; 32:1147-1157. [PMID: 30936425 DOI: 10.1038/s41379-019-0259-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 02/18/2019] [Accepted: 02/18/2019] [Indexed: 12/20/2022]
Abstract
Complement factor C4d was recently observed in renal biopsies from patients who had IgA nephropathy and a poor prognosis. We previously reported that C4d is a common denominator in microangiopathies. In this retrospective cohort study, we investigated whether C4d is a marker of microangiopathy in both IgA nephropathy and IgA vasculitis with nephritis, and whether patients with C4d and microangiopathy have poor renal outcome. We examined 128 renal biopsies from adult and pediatric patients, including normotensive and hypertensive patients, who presented with IgA nephropathy or IgA vasculitis with nephritis. Biopsies were re-evaluated in accordance with the Oxford classification, scored for additional lesions, and stained for complement proteins using immunohistochemistry, including C4d and C5b-9. Clinical data were collected with a mean (±SD) follow-up period of 51 ± 39 months. Changes in estimated glomerular filtration rate over time were compared using linear mixed-effects models. Renal survival was analyzed using multivariable Cox regression. Microangiopathic lesions were present in 20% of all biopsies (23% and 9% of patients with IgA nephropathy and IgA vasculitis with nephritis, respectively). Microangiopathy was associated with C4d and C5b-9 deposits, a higher number of chronic lesions, and hypertension (all p < 0.05). Patients with C4d and microangiopathic lesions had significantly poorer renal survival than patients without these findings, corrected for hypertension (p < 0.01). In conclusion, patients with IgA nephropathy or IgA vasculitis with nephritis with a combination of C4d positivity and microangiopathy comprise a clinical subgroup with an increased number of chronic lesions, lower estimated glomerular filtration rate, and poorer renal survival, even when corrected for hypertension. These data suggest that complement activation is involved in the development of microangiopathy in patients with IgA nephropathy and IgA vasculitis with nephritis, and that complement-mediated microangiopathy contributes to disease progression.
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Rizk DV, Maillard N, Julian BA, Knoppova B, Green TJ, Novak J, Wyatt RJ. The Emerging Role of Complement Proteins as a Target for Therapy of IgA Nephropathy. Front Immunol 2019; 10:504. [PMID: 30941137 PMCID: PMC6433978 DOI: 10.3389/fimmu.2019.00504] [Citation(s) in RCA: 100] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 02/25/2019] [Indexed: 12/28/2022] Open
Abstract
IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis worldwide and a common cause of end-stage renal disease. Evaluation of a kidney biopsy is necessary for diagnosis, with routine immunofluorescence microscopy revealing dominant or co-dominant IgA immunodeposits usually with complement C3 and sometimes IgG and/or IgM. IgA nephropathy reduces life expectancy by more than 10 years and leads to kidney failure in 20–40% of patients within 20 years of diagnosis. There is accumulating clinical, genetic, and biochemical evidence that complement plays an important role in the pathogenesis of IgA nephropathy. The presence of C3 differentiates the diagnosis of IgA nephropathy from the subclinical deposition of glomerular IgA. Markers for the activation of the alternative and mannan-binding lectin (MBL) pathways in renal-biopsy specimens are associated with disease activity and portend a worse renal outcome. Complement proteins in the circulation have also been evaluated in IgA nephropathy and found to be of prognostic value. Recently, genetic studies have identified IgA nephropathy-associated loci. Within these loci are genes encoding products involved in complement regulation and interaction with immune complexes. Put together, these data identify the complement cascade as a rational treatment target for this chronic kidney disease. Recent case reports on the successful use of humanized anti-C5 monoclonal antibody eculizumab are consistent with this hypothesis, but a better understanding of the role of complement in IgA nephropathy is needed to guide future therapeutic interventions.
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Affiliation(s)
- Dana V Rizk
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Nicolas Maillard
- Department of Nephrology, Dialysis, Transplantation, CHU de Saint-Etienne, GIMAP, EA3064, Université Jean Monnet, COMUE Université de Lyon, Rhône-Alpes, France
| | - Bruce A Julian
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Barbora Knoppova
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States.,Department of Immunology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czechia
| | - Todd J Green
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Robert J Wyatt
- Department of Pediatrics, University of Tennessee Health Sciences Center, Memphis, TN, United States
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Harris CL, Pouw RB, Kavanagh D, Sun R, Ricklin D. Developments in anti-complement therapy; from disease to clinical trial. Mol Immunol 2018; 102:89-119. [PMID: 30121124 DOI: 10.1016/j.molimm.2018.06.008] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/04/2018] [Accepted: 06/06/2018] [Indexed: 02/06/2023]
Abstract
The complement system is well known for its role in innate immunity and in maintenance of tissue homeostasis, providing a first line of defence against infection and playing a key role in flagging apoptotic cells and debris for disposal. Unfortunately complement also contributes to pathogenesis of a number of diseases; in some cases driving pathology, and in others amplifying or exacerbating the inflammatory and damaging impact of non-complement disease triggers. The role of complement in pathogenesis of an expanding number of diseases has driven industry and academia alike to develop an impressive arsenal of anti-complement drugs which target different proteins and functions of the complement cascade. Evidence from genetic and biochemical analyses, combined with improved identification of complement biomarkers and supportive data from sophisticated animal models of disease, has driven a drug development landscape in which the indications selected for clinical trial cluster in three 'target' tissues: the kidney, eye and vasculature. While the disease triggers may differ, complement activation and amplification is a common feature in many diseases which affect these three tissues. An abundance of drugs are in clinical development, some show favourable progression whereas others experience significant challenges. However, these hurdles in themselves drive an ever-evolving portfolio of 'next-generation' drugs with improved pharmacokinetic and pharmacodynamics properties. In this review we discuss the indications which are in the drug development 'spotlight' and review the relevant indication validation criteria. We present current progress in clinical trials, highlighting successes and difficulties, and look forward to approval of a wide selection of drugs for use in man which give clinicians choice in mechanistic target, modality and route of delivery.
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Affiliation(s)
- Claire L Harris
- Complement Therapeutics Research Group, Institute of Cellular Medicine, Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK; National Renal Complement Therapeutics Centre, Building 26, Royal Victoria Infirmary, Queen Victoria Road, Newcastle upon Tyne, NE1 4LP, UK.
| | - Richard B Pouw
- Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, CH-4056, Basel, Switzerland
| | - David Kavanagh
- Complement Therapeutics Research Group, Institute of Cellular Medicine, Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK; National Renal Complement Therapeutics Centre, Building 26, Royal Victoria Infirmary, Queen Victoria Road, Newcastle upon Tyne, NE1 4LP, UK
| | - Ruyue Sun
- Complement Therapeutics Research Group, Institute of Cellular Medicine, Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Daniel Ricklin
- Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, CH-4056, Basel, Switzerland.
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25
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Zagkotsis G, Vourlakou C, Paraskevopoulos A, Apostolou T. Recurrence of crescentic IgA nephropathy after renal transplantation. CEN Case Rep 2018; 7:268-273. [PMID: 29802527 DOI: 10.1007/s13730-018-0341-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 05/19/2018] [Indexed: 12/01/2022] Open
Abstract
IgA nephropathy (IgAN) is one of the most common recurrent glomerulonephritis after renal transplantation. Rarely, it is accompanied with the presence of crescents that leads to rapid deterioration of renal function and graft loss. We present a 54-year-old patient with IgAN that received a cadaveric kidney allograft, but developed biopsy proven recurrent IgAN 7 months after renal transplantation. He was treated with intravenous steroids and angiotensin-converting enzyme inhibitor and remission was achieved. 4 years later, he presented again with heavy proteinuria, hematuria and deterioration of renal function. Allograft biopsy revealed recurrent IgAN with crescents, which was successfully treated with pulse intravenous steroids and six monthly doses of intravenous cyclophosphamide. This regime resulted in long-term sustained remission with a stable functioning graft 3 years later. Although it is not an established treatment as in native kidneys, intravenous cyclophosphamide should probably be considered in kidney transplants with potentially reversible recurrent crescentic IgAN.
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Affiliation(s)
- Georgios Zagkotsis
- Department of Nephrology, General Hospital of Livadeia, Ag. Vlassiou Str, 32100, Livadeia, Greece.
- Department of Nephrology, "Evaggelismos" General Hospital of Athens, Athens, Greece.
| | - Christina Vourlakou
- Department of Histopathology, "Evaggelismos" General Hospital of Athens, Athens, Greece
| | | | - Theofanis Apostolou
- Department of Nephrology, "Evaggelismos" General Hospital of Athens, Athens, Greece
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26
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Penfold RS, Prendecki M, McAdoo S, Tam FWK. Primary IgA nephropathy: current challenges and future prospects. Int J Nephrol Renovasc Dis 2018; 11:137-148. [PMID: 29695925 PMCID: PMC5905843 DOI: 10.2147/ijnrd.s129227] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis worldwide, exhibiting a variable clinical and pathological course and significantly contributing to the global burden of chronic kidney disease and end-stage renal disease. Current standards of care focus on optimization of antihypertensive and antiproteinuric therapies (typically renin- angiotensin system blockade) to reduce disease progression. Much recent attention has focused on whether additional immunosuppression confers better outcomes than supportive management alone, and indeed, several trials have demonstrated renoprotective effects following the use of oral corticosteroids. However, results have been inconsistent, and perceived benefits must be balanced against risks and adverse effects associated with generalized immunosuppression, as highlighted by the high-profile STOP-IgAN and TESTING clinical trials. Recent translational research in vitro and animal models of IgAN have generated greater insight into potential therapeutic targets for this complex autoimmune disease. Deeper understanding of the roles of the mucosal immune barrier, complement activation and deposition, T-cell dependent and independent mechanisms of B cell activation, and of the deposition and downstream inflammatory signaling pathways of nephritogenic polymeric IgA1 complexes (e.g., signaling of immune receptors via spleen tyrosine kinase) has formed the rationale for the development of novel agents and clinical trials of more targeted therapies. However, translating findings into clinical practice is challenging, with many immunopathological features of IgAN specific to humans. Recent comprehensive reviews outline current understanding of mechanisms of IgAN as well as ongoing and future clinical trials; it is not our aim to replicate this here. Instead, we take a mechanistic approach to current treatment strategies, outlining advantages and limitations of each before exploring ongoing research with potential translation into future targeted therapies for this complex disease.
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Affiliation(s)
- Rose S Penfold
- Renal and Vascular Inflammation Section, Department of Medicine, Imperial College London, London, UK
| | - Maria Prendecki
- Renal and Vascular Inflammation Section, Department of Medicine, Imperial College London, London, UK
| | - Stephen McAdoo
- Renal and Vascular Inflammation Section, Department of Medicine, Imperial College London, London, UK
| | - Frederick WK Tam
- Renal and Vascular Inflammation Section, Department of Medicine, Imperial College London, London, UK
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27
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Nakamura H, Anayama M, Makino M, Makino Y, Tamura K, Nagasawa M. Atypical Hemolytic Uremic Syndrome Associated with Complement Factor H Mutation and IgA Nephropathy: A Case Report Successfully Treated with Eculizumab. Nephron Clin Pract 2017; 138:324-327. [DOI: 10.1159/000485194] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 11/09/2017] [Indexed: 01/27/2023] Open
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28
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Medjeral-Thomas NR, Troldborg A, Constantinou N, Lomax-Browne HJ, Hansen AG, Willicombe M, Pusey CD, Cook HT, Thiel S, Pickering MC. Progressive IgA Nephropathy Is Associated With Low Circulating Mannan-Binding Lectin-Associated Serine Protease-3 (MASP-3) and Increased Glomerular Factor H-Related Protein-5 (FHR5) Deposition. Kidney Int Rep 2017; 3:426-438. [PMID: 29725647 PMCID: PMC5932138 DOI: 10.1016/j.ekir.2017.11.015] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 11/16/2017] [Accepted: 11/21/2017] [Indexed: 12/16/2022] Open
Abstract
Introduction IgA nephropathy (IgAN) is characterized by glomerular deposition of galactose-deficient IgA1 and complement proteins and leads to renal impairment. Complement deposition through the alternative and lectin activation pathways is associated with renal injury. Methods To elucidate the contribution of the lectin pathway to IgAN, we measured the 11 plasma lectin pathway components in a well-characterized cohort of patients with IgAN. Results M-ficolin, L-ficolin, mannan-binding lectin (MBL)-associated serine protease (MASP)-1 and MBL-associated protein (MAp) 19 were increased, whereas plasma MASP-3 levels were decreased in patients with IgAN compared with healthy controls. Progressive disease was associated with low plasma MASP-3 levels and increased glomerular staining for C3b/iC3b/C3c, C3d, C4d, C5b-9, and factor H-related protein 5 (FHR5). Glomerular FHR5 deposition positively correlated with glomerular C3b/iC3b/C3c, C3d, and C5b-9 deposition, but not with glomerular C4d. These observations, together with the finding that glomerular factor H (fH) deposition was reduced in progressive disease, are consistent with a role for fH deregulation by FHR5 in renal injury in IgAN. Conclusion Our data indicate that circulating MASP-3 levels could be used as a biomarker of disease severity in IgAN and that glomerular staining for FHR5 could both indicate alternative complement pathway activation and be a tissue marker of disease severity.
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Affiliation(s)
| | - Anne Troldborg
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.,Department of Rheumatology, Aarhus University Hospital, Aarhus, Denmark
| | - Nicholas Constantinou
- Centre for Complement and Inflammation Research, Imperial College London, London, UK
| | - Hannah J Lomax-Browne
- Centre for Complement and Inflammation Research, Imperial College London, London, UK
| | | | - Michelle Willicombe
- Renal and Transplant Centre, Imperial College Healthcare NHS Trust, London, UK
| | - Charles D Pusey
- Renal and Vascular Inflammation Section, Imperial College London, London, UK
| | - H Terence Cook
- Centre for Complement and Inflammation Research, Imperial College London, London, UK
| | - Steffen Thiel
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Matthew C Pickering
- Centre for Complement and Inflammation Research, Imperial College London, London, UK
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