1
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Vonbrunn E, Daniel C. [The complement cascade in renal pathology]. PATHOLOGIE (HEIDELBERG, GERMANY) 2024; 45:246-253. [PMID: 38578365 DOI: 10.1007/s00292-024-01320-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/28/2024] [Indexed: 04/06/2024]
Abstract
The complement cascade comprises a variety of soluble and cell surface proteins and is an important component of the innate immune system. When the cascade is triggered by any of the three activation pathways, the complement system rapidly produces large amounts of protein fragments that are potent mediators of inflammatory, vasoactive, and metabolic responses. All activation pathways lead to the terminal complement cascade with the formation of the membrane attack complex, which lyses cells by forming membrane pores. Although the complement system is essential for pathogen defense and homeostasis, excessive or uncontrolled activation can lead to tissue damage. Recent research shows that the complement system is activated in almost all kidney diseases, even those not traditionally considered immune-mediated. In directly complement-mediated kidney diseases, complement factors or regulators are defective, afunctional or inactivated by antibodies. In many other renal diseases, the complement system is activated secondarily as a result of renal damage and is therefore involved in the pathogenesis of the disease, but is not the trigger. The detection of complement deposits is also used to diagnose kidney disease. This review describes the structure of the complement system and the effects of its dysregulation as a cause and modulator of renal disease.
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Affiliation(s)
- E Vonbrunn
- Abteilung Nephropathologie, Pathologisches Institut, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Krankenhausstr. 8-10, 91054, Erlangen, Deutschland
| | - C Daniel
- Abteilung Nephropathologie, Pathologisches Institut, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Krankenhausstr. 8-10, 91054, Erlangen, Deutschland.
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2
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Obata S, Hullekes F, Riella LV, Cravedi P. Recurrent complement-mediated Hemolytic uremic syndrome after kidney transplantation. Transplant Rev (Orlando) 2024; 38:100857. [PMID: 38749097 DOI: 10.1016/j.trre.2024.100857] [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: 03/13/2024] [Revised: 04/25/2024] [Accepted: 04/26/2024] [Indexed: 06/16/2024]
Abstract
Hereditary forms of hemolytic uremic syndrome (HUS), formerly known as atypical HUS, typically involve mutations in genes encoding for components of the alternative pathway of complement, therefore they are often referred to as complement-mediated HUS (cHUS). This condition has a high risk of recurrence in the transplanted kidney, leading to accelerated graft loss. The availability of anti-complement component C5 antibody eculizumab has enabled successful transplantation with a notably reduced recurrence rate and improved prognosis. Open questions are related to the potential for complement inhibitor discontinuation, ideal timing of treatment withdrawal, and patient selection based on genetic abnormalities. Our review delves into the pathophysiology, classification, genetic predispositions, and management strategies for cHUS in the native and transplant kidneys.
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Affiliation(s)
- Shota Obata
- Precision Immunology Institute, Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, United States of America
| | - Frank Hullekes
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States of America
| | - Leonardo V Riella
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States of America; Department of Medicine, Nephrology Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States of America
| | - Paolo Cravedi
- Precision Immunology Institute, Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, United States of America.
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3
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Nester C, Decker DA, Meier M, Aslam S, Bomback AS, Caravaca-Fontán F, Cook TH, Feldman DL, Fremeaux-Bacchi V, Gale DP, Gooch A, Johnson S, Licht C, Mathur M, Pickering MC, Praga M, Remuzzi G, Selvarajah V, Smith RJ, Tabriziani H, van de Kar N, Wang Y, Wong E, Mistry K, Lim M, Portillo C, Balogun S, Trachtman H, Thompson A. Developing Therapies for C3 Glomerulopathy: Report of the Kidney Health Initiative C3 Glomerulopathy Trial Endpoints Work Group. Clin J Am Soc Nephrol 2024; 19:01277230-990000000-00395. [PMID: 38829708 PMCID: PMC11390019 DOI: 10.2215/cjn.0000000000000505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 05/28/2024] [Indexed: 06/05/2024]
Abstract
Randomized clinical trials are underway to evaluate the efficacy of novel agents targeting the alternative complement pathway in patients with C3 glomerulopathy (C3G), a rare glomerular disease. The Kidney Health Initiative convened a panel of experts in C3G to ( 1 ) assess the data supporting the use of the prespecified trial end points as measures of clinical benefit and ( 2 ) opine on efficacy findings they would consider compelling as treatment(s) of C3G in native kidneys. Two subpanels of the C3G Trial Endpoints Work Group reviewed the available evidence and uncertainties for the association between the three prespecified end points-( 1 ) proteinuria, ( 2 ) eGFR, and ( 3 ) histopathology-and anticipated outcomes. The full work group provided feedback on the summaries provided by the subpanels and on what potential treatment effects on the proposed end points they would consider compelling to support evidence of an investigational product's effectiveness for treating C3G. Members of the full work group agreed with the characterization of the data, evidence, and uncertainties, supporting the end points. Given the limitations of the available data, the work group was unable to define a minimum threshold for change in any of the end points that might be considered clinically meaningful. The work group concluded that a favorable treatment effect on all three end points would provide convincing evidence of efficacy in the setting of a therapy that targeted the complement pathway. A therapy might be considered effective in the absence of complete alignment in all three end points if there was meaningful lowering of proteinuria and stabilization or improvement in eGFR. The panel unanimously supported efforts to foster data sharing between academic and industry partners to address the gaps in the current knowledge identified by the review of the end points in the aforementioned trials.
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Affiliation(s)
- Carla Nester
- Department of Pediatrics, Division of Nephrology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Dima A Decker
- Apellis Pharmaceuticals Inc., Waltham, Massachusetts
| | | | - Shakil Aslam
- BioCryst Pharmaceuticals Inc., Durham, North Carolina
| | | | | | - Terence H Cook
- Department of Immunology and Inflammation, Imperial College London, London, United Kingdom
| | | | | | - Daniel P Gale
- Department of Renal Medicine, University College of London, London, United Kingdom
- Rare Kidney Disease Registry (RaDaR), Bristol, United Kingdom
| | - Ann Gooch
- BioCryst Pharmaceuticals Inc., Durham, North Carolina
| | - Sally Johnson
- Great North Children's Hospital, Newcastle upon Tyne, United Kingdom
| | | | | | - Matthew C Pickering
- Department of Immunology and Inflammation, Imperial College London, London, United Kingdom
| | - Manuel Praga
- Department of Medicine, Nephrology Department, Complutense University, Madrid, Spain
| | - Giuseppe Remuzzi
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Viknesh Selvarajah
- Research and Early Development, Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom
| | - Richard J Smith
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | | | - Nicole van de Kar
- Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University, Nijmegen, The Netherlands
| | | | - Edwin Wong
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Kirtida Mistry
- Center for the Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland
| | - Mark Lim
- Kidney Health Initiative, American Society of Nephrology, Washington, DC
| | - Cesia Portillo
- Kidney Health Initiative, American Society of Nephrology, Washington, DC
| | - Seyi Balogun
- Kidney Health Initiative, American Society of Nephrology, Washington, DC
| | - Howard Trachtman
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan
| | - Aliza Thompson
- Center for the Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland
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4
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Wooden B, Nester CM, Bomback AS. Update on C3 Glomerulopathy. ADVANCES IN KIDNEY DISEASE AND HEALTH 2024; 31:223-233. [PMID: 39004462 DOI: 10.1053/j.akdh.2024.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 05/13/2024] [Accepted: 05/20/2024] [Indexed: 07/16/2024]
Abstract
C3 glomerulopathy (C3G) is a rare disorder marked by deposition of C3 in the glomerulus, resulting in damage to the glomerular filtration unit and presenting with features of the nephritic and nephrotic syndromes. Fundamentally, C3G is caused by dysregulation of the alternative pathway of the complement cascade, either due to genetic variants or acquired humoral factors. Despite significant advances in recent years in the understanding of the underlying mechanisms and culprit lesions that result in the development of C3G, treatment options remain severely limited, and the prognosis is often poor. Fortunately, a number of anticomplement therapies are emerging from the drug development pipeline, with several in late-stage testing in patients with C3G, and there is hope that we will soon have more targeted options for managing patients with this devastating disease. In this review, we provide an overview of C3G, as well as summarizing the evidence for current treatments and detailing the clinical trials that are currently underway.
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Affiliation(s)
- Benjamin Wooden
- Division of Nephrology, Department of Medicine, Columbia University, New York, NY.
| | - Carla M Nester
- Division of Nephrology, Department of Medicine, University of Iowa, Iowa City, IA
| | - Andrew S Bomback
- Division of Nephrology, Department of Medicine, Columbia University, New York, NY
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5
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Liu F, Ryan ST, Fahnoe KC, Morgan JG, Cheung AE, Storek MJ, Best A, Chen HA, Locatelli M, Xu S, Schmidt E, Schmidt-Jiménez LF, Bieber K, Henderson JM, Lian CG, Verschoor A, Ludwig RJ, Benigni A, Remuzzi G, Salant DJ, Kalled SL, Thurman JM, Holers VM, Violette SM, Wawersik S. C3d-Targeted factor H inhibits tissue complement in disease models and reduces glomerular injury without affecting circulating complement. Mol Ther 2024; 32:1061-1079. [PMID: 38382529 PMCID: PMC11163200 DOI: 10.1016/j.ymthe.2024.02.001] [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: 06/30/2023] [Revised: 01/02/2024] [Accepted: 02/01/2024] [Indexed: 02/23/2024] Open
Abstract
Complement-mediated diseases can be treated using systemic inhibitors. However, complement components are abundant in circulation, affecting systemic inhibitors' exposure and efficacy. Furthermore, because of complement's essential role in immunity, systemic treatments raise infection risk in patients. To address these challenges, we developed antibody fusion proteins combining the alternative-pathway complement inhibitor factor H (fH1-5) with an anti-C3d monoclonal antibody (C3d-mAb-2fH). Because C3d is deposited at sites of complement activity, this molecule localizes to tissue complement while minimizing circulating complement engagement. These fusion proteins bind to deposited complement in diseased human skin sections and localize to activated complement in a primate skin injury model. We further explored the pharmacology of C3d-mAb-2fH proteins in rodent models with robust tissue complement activation. Doses of C3d-mAb-2fH >1 mg/kg achieved >75% tissue complement inhibition in mouse and rat injury models while avoiding circulating complement blockade. Glomerular-specific complement inhibition reduced proteinuria and preserved podocyte foot-process architecture in rat membranous nephropathy, indicating disease-modifying efficacy. These data indicate that targeting local tissue complement results in durable and efficacious complement blockade in skin and kidney while avoiding systemic inhibition, suggesting broad applicability of this approach in treating a range of complement-mediated diseases.
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Affiliation(s)
- Fei Liu
- Q32 Bio, Waltham, MA 02451, USA
| | | | | | | | | | | | | | - Hui A Chen
- Department of Pathology and Laboratory Medicine, Chobanian and Avedisian School of Medicine at Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Monica Locatelli
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, 24126 Bergamo, Italy
| | - Shuyun Xu
- Department of Pathology, Brigham & Women's Hospital/Harvard Medical School, Boston, MA 02115, USA
| | - Enno Schmidt
- Lübeck Institute of Experimental Dermatology, University of Lübeck, 23562 Lübeck, Germany
| | - Leon F Schmidt-Jiménez
- Lübeck Institute of Experimental Dermatology, University of Lübeck, 23562 Lübeck, Germany
| | - Katja Bieber
- Lübeck Institute of Experimental Dermatology, University of Lübeck, 23562 Lübeck, Germany
| | - Joel M Henderson
- Department of Pathology and Laboratory Medicine, Chobanian and Avedisian School of Medicine at Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Christine G Lian
- Department of Pathology, Brigham & Women's Hospital/Harvard Medical School, Boston, MA 02115, USA
| | - Admar Verschoor
- Department of Otorhinolaryngology, Technische Universität München and Klinikum Rechts der Isar, 81675 Munich, Germany; Department of Dermatology, University Hospital Schleswig-Holstein, University of Lübeck, 23562 Lübeck, Germany
| | - Ralf J Ludwig
- Lübeck Institute of Experimental Dermatology, University of Lübeck, 23562 Lübeck, Germany
| | - Ariela Benigni
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, 24126 Bergamo, Italy
| | - Giuseppe Remuzzi
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, 24126 Bergamo, Italy
| | - David J Salant
- Department of Medicine, Chobanian and Avedisian School of Medicine at Boston University and Section of Nephrology, Boston Medical Center, Boston, MA 02118, USA
| | | | - Joshua M Thurman
- Department of Medicine, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - V Michael Holers
- Department of Medicine, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO 80045, USA
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6
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Obata S, Vaz de Castro PAS, Riella LV, Cravedi P. Recurrent C3 glomerulopathy after kidney transplantation. Transplant Rev (Orlando) 2024; 38:100839. [PMID: 38412598 DOI: 10.1016/j.trre.2024.100839] [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: 01/25/2024] [Revised: 02/17/2024] [Accepted: 02/19/2024] [Indexed: 02/29/2024]
Abstract
The complement system is part of innate immunity and is pivotal in protecting the body against pathogens and maintaining host homeostasis. Activation of the complement system is triggered through multiple pathways, including antibody deposition, a mannan-binding lectin, or activated complement deposition. C3 glomerulopathy (C3G) is a rare glomerular disease driven by complement dysregulation with high post-transplantation recurrence rates. Its treatment is mainly based on immunosuppressive therapies, specifically mycophenolate mofetil and glucocorticoids. Recent years have seen significant progress in understanding complement biology and its role in C3G pathophysiology. New complement-tergeting treatments have been developed and initial trials have shown promising results. However, challenges persist in C3G, with recurrent post-transplantation cases leading to suboptimal outcomes. This review discusses the pathophysiology and management of C3G, with a focus on its recurrence after kidney transplantation.
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Affiliation(s)
- Shota Obata
- Precision Immunology Institute, Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, United States of America
| | - Pedro A S Vaz de Castro
- Interdisciplinary Laboratory of Medical Investigation, Unit of Pediatric Nephrology, Faculty of Medicine, Federal University of Minas Gerais (UFMG), Brazil
| | - Leonardo V Riella
- Division of Nephrology and Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States of America
| | - Paolo Cravedi
- Precision Immunology Institute, Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, United States of America.
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7
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Zhang Y, Martin B, Spies MA, Roberts SM, Nott J, Goodfellow RX, Nelson AFM, Blain SJ, Redondo E, Nester CM, Smith RJH. Renin and renin blockade have no role in complement activity. Kidney Int 2024; 105:328-337. [PMID: 38008161 PMCID: PMC10872535 DOI: 10.1016/j.kint.2023.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 11/08/2023] [Accepted: 11/10/2023] [Indexed: 11/28/2023]
Abstract
Renin, an aspartate protease, regulates the renin-angiotensin system by cleaving its only known substrate angiotensinogen to angiotensin. Recent studies have suggested that renin may also cleave complement component C3 to activate complement or contribute to its dysregulation. Typically, C3 is cleaved by C3 convertase, a serine protease that uses the hydroxyl group of a serine residue as a nucleophile. Here, we provide seven lines of evidence to show that renin does not cleave C3. First, there is no association between renin plasma levels and C3 levels in patients with C3 Glomerulopathies (C3G) and atypical Hemolytic Uremic Syndrome (aHUS), implying that serum C3 consumption is not increased in the presence of high renin. Second, in vitro tests of C3 conversion to C3b do not detect differences when sera from patients with high renin levels are compared to sera from patients with normal/low renin levels. Third, aliskiren, a renin inhibitor, does not block abnormal complement activity introduced by nephritic factors in the fluid phase. Fourth, aliskiren does not block dysregulated complement activity on cell surfaces. Fifth, recombinant renin from different sources does not cleave C3 even after 24 hours of incubation at 37 °C. Sixth, direct spiking of recombinant renin into sera samples of patients with C3G and aHUS does not enhance complement activity in either the fluid phase or on cell surfaces. And seventh, molecular modeling and docking place C3 in the active site of renin in a position that is not consistent with a productive ground state complex for catalytic hydrolysis. Thus, our study does not support a role for renin in the activation of complement.
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Affiliation(s)
- Yuzhou Zhang
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Bertha Martin
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - M Ashley Spies
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA; Departments of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa, USA
| | - Sarah M Roberts
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Joel Nott
- Protein Facility, Office of Biotechnology, Iowa State University, Ames, Iowa, USA
| | - Renee X Goodfellow
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Angela F M Nelson
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Samantha J Blain
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Elena Redondo
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Carla M Nester
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Richard J H Smith
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.
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8
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Miwa T, Sato S, Golla M, Song WC. Expansion of Anticomplement Therapy Indications from Rare Genetic Disorders to Common Kidney Diseases. Annu Rev Med 2024; 75:189-204. [PMID: 37669567 DOI: 10.1146/annurev-med-042921-102405] [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] [Indexed: 09/07/2023]
Abstract
Complement constitutes a major part of the innate immune system. The study of complement in human health has historically focused on infection risks associated with complement protein deficiencies; however, recent interest in the field has focused on overactivation of complement as a cause of immune injury and the development of anticomplement therapies to treat human diseases. The kidneys are particularly sensitive to complement injury, and anticomplement therapies for several kidney diseases have been investigated. Overactivation of complement can result from loss-of-function mutations in complement regulators; gain-of-function mutations in key complement proteins such as C3 and factor B; or autoantibody production, infection, or tissue stresses, such as ischemia and reperfusion, that perturb the balance of complement activation and regulation. Here, we provide a high-level review of the status of anticomplement therapies, with an emphasis on the transition from rare diseases to more common kidney diseases.
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Affiliation(s)
- Takashi Miwa
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; , , ,
| | - Sayaka Sato
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; , , ,
| | - Madhu Golla
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; , , ,
| | - Wen-Chao Song
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; , , ,
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9
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Wei J, Huang Y, Yuan S, Chen X, Fu X, Li Z, Li Y, Sun L, Liu H, Zhu X. Clinical and pathological features of 52 patients with glomerulonephritis with dominant C3. ZHONG NAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF CENTRAL SOUTH UNIVERSITY. MEDICAL SCIENCES 2024; 49:75-83. [PMID: 38615169 PMCID: PMC11017022 DOI: 10.11817/j.issn.1672-7347.2024.230328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Indexed: 04/15/2024]
Abstract
OBJECTIVES With the in-depth study of complement dysregulation, glomerulonephritis with dominant C3 has received increasing attention, with a variety of pathologic types and large differences in symptoms and prognosis between pathologic types. This study analyzes the clinical, pathological, and prognostic characteristics of different pathological types of glomerulonephritis with dominant C3, aiming to avoid misdiagnosis and missed diagnoses. METHODS The clinical, pathological, and follow-up data of 52 patients diagnosed as glomerulonephritis with dominant C3 by renal biopsy from June 2013 to October 2022 were retrospectively analyzed. According to the clinical feature and results of pathology, 15 patients with post-infectious glomerulonephritis (PIGN) and 37 patients with of non-infectious glomerulonephritis (N-PIGN) were classified. N-PIGN subgroup analysis was performed, and 16 patients were assigned into a C3-alone-deposition group and 21 in a C3-dominant-deposition group, or 27 in a C3 glomerulopathy (C3G) group and 10 in a non-C3 nephropathy (N-C3G) group. RESULTS The PIGN group had lower creatinine values (84.60 μmol/L vs179.62 μmol/L, P=0.001), lower complement C3 values (0.36 g/L vs0.74 g/L, P<0.001) at biopsy, and less severe pathological chronic lesions compared with the N-PIGN group. In the N-PIGN subgroup analysis, the C3-dominant-deposition group had higher creatinine values (235.30 μmol/L vs106.70 μmol/L, P=0.004) and higher 24-hour urine protein values (4 025.62 mg vs1 981.11 mg, P=0.037) than the C3-alone-deposition group. The prognosis of kidney in the PIGN group (P=0.049), the C3-alone-deposition group (P=0.017), and the C3G group (P=0.018) was better than that in the N-PIGN group, the C3-dominant-deposition group, and the N-C3G group, respectively. CONCLUSIONS Glomerulonephritis with dominant C3 covers a variety of pathological types, and PIGN needs to be excluded before diagnosing C3G because of considerable overlap with atypical PIGN and C3G; in addition, the deposition of C1q complement under fluorescence microscope may indicate poor renal prognosis, and relevant diagnosis, treatment, and follow-up should be strengthened.
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Affiliation(s)
- Jinying Wei
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011.
- Institute of Nephrology, Central South University, Changsha 410011.
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China.
| | - Yao Huang
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Nephrology, Central South University, Changsha 410011
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China
| | - Shuguang Yuan
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Nephrology, Central South University, Changsha 410011
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China
| | - Xiaojun Chen
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Nephrology, Central South University, Changsha 410011
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China
| | - Xiao Fu
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Nephrology, Central South University, Changsha 410011
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China
| | - Zheng Li
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Nephrology, Central South University, Changsha 410011
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China
| | - Ying Li
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Nephrology, Central South University, Changsha 410011
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China
| | - Lin Sun
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Nephrology, Central South University, Changsha 410011
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China
| | - Hong Liu
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Nephrology, Central South University, Changsha 410011
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China
| | - Xuejing Zhu
- Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha 410011.
- Institute of Nephrology, Central South University, Changsha 410011.
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China.
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10
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Wong E, Nester C, Cavero T, Karras A, Le Quintrec M, Lightstone L, Eisenberger U, Soler MJ, Kavanagh D, Daina E, Praga M, Medjeral-Thomas NR, Gäckler A, Garcia-Carro C, Biondani A, Chaperon F, Kulmatycki K, Milojevic J, Webb NJ, Nidamarthy PK, Junge G, Remuzzi G. Efficacy and Safety of Iptacopan in Patients With C3 Glomerulopathy. Kidney Int Rep 2023; 8:2754-2764. [PMID: 38106570 PMCID: PMC10719607 DOI: 10.1016/j.ekir.2023.09.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/21/2023] [Accepted: 09/11/2023] [Indexed: 12/19/2023] Open
Abstract
Introduction Complement 3 glomerulopathy (C3G) is a rare inflammatory kidney disease mediated by dysregulation of the alternative complement pathway. No targeted therapy exists for this aggressive glomerulonephritis. Efficacy, safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) (measured by complement biomarkers) of iptacopan were assessed in patients with C3G. Methods In this phase 2, multicenter, open-label, single-arm, nonrandomized study, adults with biopsy-proven, native kidney C3G (native cohort) and kidney transplant recipients with C3G recurrence (recurrent kidney transplant [KT] cohort) received iptacopan twice daily (bid) for 84 days (days 1-21: 10-100 mg; days 22-84: 200 mg). The primary end point was the urine protein-to-creatinine ratio (UPCR; native cohort) and the change in the C3 deposit score of kidney biopsy (recurrent KT cohort). The complement pathway measures included Wieslab assay, soluble C5b9, and serum C3 levels. Results A total of 27 patients (16 native cohort and 11 recurrent KT cohort) were enrolled and all completed the study. In the native cohort, UPCR levels decreased by 45% from baseline to week 12 (P = 0.0003). In the recurrent KT cohort, the median C3 deposit score decreased by 2.50 (scale: 0-12) on day 84 versus baseline (P = 0.03). Serum C3 levels were normalized in most patients; complement hyperactivity observed pretreatment was reduced. Severe adverse events (AEs) included post-biopsy hematuria and hyperkalemia. No deaths occurred during the study. Conclusion Iptacopan resulted in statistically significant and clinically important reductions in UPCR and normalization of serum C3 levels in the native cohort and reduced C3 deposit scores in the recurrent KT cohort with favorable safety and tolerability. (ClinicalTrials.gov identifier: NCT03832114).
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Affiliation(s)
- Edwin Wong
- National Renal Complement Therapeutics Centre, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle Upon Tyne, UK
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Carla Nester
- The University of Iowa Stead Family Children’s Hospital, Iowa City, Iowa, USA
| | - Teresa Cavero
- Nephrology Department, University Hospital Doce de Octubre, Madrid, Spain
| | - Alexandre Karras
- Department of Nephrology, Hôpital Européen Georges-Pompidou, APHP, Paris, France
| | - Moglie Le Quintrec
- Service de Néphrologie et Transplantation Rénale, Centre Hospitalier Universitaire de Montpellier, Montpellier, France
| | - Liz Lightstone
- Centre for Inflammatory Disease, Department of Immunology and Inflammation, Imperial College London, London, UK
| | - Ute Eisenberger
- Department of Nephrology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Maria Jose Soler
- Nephrology Department, Vall d’Hebron University Hospital, Vall d’Hebron Institute of Research, CSUR National Unit of Expertise for Complex Glomerular Diseases of Spain, Barcelona, Spain
| | - David Kavanagh
- National Renal Complement Therapeutics Centre, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle Upon Tyne, UK
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Erica Daina
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy
| | - Manuel Praga
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain
| | - Nicholas R. Medjeral-Thomas
- Centre for Inflammatory Disease, Department of Immunology and Inflammation, Imperial College London, London, UK
| | - Anja Gäckler
- Department of Nephrology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Clara Garcia-Carro
- Nephrology Department, Vall d’Hebron University Hospital, Vall d’Hebron Institute of Research, CSUR National Unit of Expertise for Complex Glomerular Diseases of Spain, Barcelona, Spain
| | - Andrea Biondani
- Novartis Institutes for BioMedical Research, Translational Medicine, Novartis AG, Basel, Switzerland
| | - Frederique Chaperon
- Novartis Institutes for BioMedical Research, Translational Medicine, Novartis AG, Basel, Switzerland
| | - Kenneth Kulmatycki
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, USA
| | - Julie Milojevic
- Novartis Institutes for BioMedical Research, Translational Medicine, Novartis AG, Basel, Switzerland
| | - Nicholas J.A. Webb
- Novartis Institutes for BioMedical Research, Translational Medicine, Novartis AG, Basel, Switzerland
| | | | - Guido Junge
- Novartis Institutes for BioMedical Research, Translational Medicine, Novartis AG, Basel, Switzerland
| | - Giuseppe Remuzzi
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy
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11
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Esposito P, Picciotto D, Costigliolo F, Russo E, Macciò L, Cenacchi G, Cagnetta A, Cea M, Lemoli RM, Viazzi F. Daratumumab in the treatment of C3 glomerulopathy with monoclonal gammopathy: a case report and literature review. Front Med (Lausanne) 2023; 10:1266172. [PMID: 37724175 PMCID: PMC10505429 DOI: 10.3389/fmed.2023.1266172] [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: 07/24/2023] [Accepted: 08/21/2023] [Indexed: 09/20/2023] Open
Abstract
Although rare, C3 glomerulopathy (C3G) is increasingly recognized thanks to the currently available diagnostic skills. C3G is not a single disease but a group of disorders with distinct pathogenesis and progression. Thus, an essential step for its management remains an in-depth characterization of the specific form and the identification of underlying conditions, which may also impact treatment choices as well. Among these entities, an emerging condition is the association of C3G with monoclonal gammopathy, which confers poor outcomes. Overall, diagnosis of C3G remains challenging, and determining the appropriate treatment remains unclear. Conventional immunosuppressive therapy has proven ineffective in such cases, while clone-directed therapies have shown promising results in small interventional studies and case series. Here, we report a case of a patient affected by C3G with monoclonal gammopathy of renal significance who experienced rapid deterioration of kidney function requiring replacement therapy. After the failure of first-line treatment, a switch to the anti-CD38 therapy with daratumumab resulted in the progressive improvement of the patient's kidney function, leading to the discontinuation of hemodialysis after approximately 10 months. Serial renal biopsies were also performed to study the disease's evolution in response to the treatment. Based on the description of this single case, we have comprehensively reviewed available studies on daratumumab use in patients with C3G associated with monoclonal gammopathy to provide insights for the design of prospective studies which aim to enhance the management of such poor prognosis disease.
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Affiliation(s)
- Pasquale Esposito
- Unit of Nephrology, Dialysis, and Transplantation, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
- Department of Internal Medicine and Medical Specialties (DiMI), University of Genoa, Genoa, Italy
| | - Daniela Picciotto
- Unit of Nephrology, Dialysis, and Transplantation, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Francesca Costigliolo
- Unit of Nephrology, Dialysis, and Transplantation, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Elisa Russo
- Unit of Nephrology, Dialysis, and Transplantation, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
- Department of Internal Medicine and Medical Specialties (DiMI), University of Genoa, Genoa, Italy
| | - Lucia Macciò
- Department of Internal Medicine and Medical Specialties (DiMI), University of Genoa, Genoa, Italy
| | - Giovanna Cenacchi
- Biotechnology and Methods in Laboratory Medicine, Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy
| | - Antonia Cagnetta
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
- Clinic of Hematology, Department of Internal Medicine and Medical Specialties (DiMI), University of Genoa, Genoa, Italy
| | - Michele Cea
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
- Clinic of Hematology, Department of Internal Medicine and Medical Specialties (DiMI), University of Genoa, Genoa, Italy
| | - Roberto M. Lemoli
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
- Clinic of Hematology, Department of Internal Medicine and Medical Specialties (DiMI), University of Genoa, Genoa, Italy
| | - Francesca Viazzi
- Unit of Nephrology, Dialysis, and Transplantation, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
- Department of Internal Medicine and Medical Specialties (DiMI), University of Genoa, Genoa, Italy
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12
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Anders HJ, Kitching AR, Leung N, Romagnani P. Glomerulonephritis: immunopathogenesis and immunotherapy. Nat Rev Immunol 2023; 23:453-471. [PMID: 36635359 PMCID: PMC9838307 DOI: 10.1038/s41577-022-00816-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2022] [Indexed: 01/14/2023]
Abstract
'Glomerulonephritis' (GN) is a term used to describe a group of heterogeneous immune-mediated disorders characterized by inflammation of the filtration units of the kidney (the glomeruli). These disorders are currently classified largely on the basis of histopathological lesion patterns, but these patterns do not align well with their diverse pathological mechanisms and hence do not inform optimal therapy. Instead, we propose grouping GN disorders into five categories according to their immunopathogenesis: infection-related GN, autoimmune GN, alloimmune GN, autoinflammatory GN and monoclonal gammopathy-related GN. This categorization can inform the appropriate treatment; for example, infection control for infection-related GN, suppression of adaptive immunity for autoimmune GN and alloimmune GN, inhibition of single cytokines or complement factors for autoinflammatory GN arising from inborn errors in innate immunity, and plasma cell clone-directed or B cell clone-directed therapy for monoclonal gammopathies. Here we present the immunopathogenesis of GN and immunotherapies in use and in development and discuss how an immunopathogenesis-based GN classification can focus research, and improve patient management and teaching.
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Affiliation(s)
- Hans-Joachim Anders
- Division of Nephrology, Department of Medicine IV, University Hospital, Ludwig Maximilian University Munich, Munich, Germany.
| | - A Richard Kitching
- Centre for Inflammatory Diseases, Monash University Department of Medicine, Monash Medical Centre, Clayton, VIC, Australia
- Department of Nephrology, Monash Health, Clayton, VIC, Australia
- Department of Paediatric Nephrology, Monash Health, Clayton, VIC, Australia
| | - Nelson Leung
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - Paola Romagnani
- Department of Experimental and Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy
- Nephrology and Dialysis Unit, Meyer Children's Hospital IRCCS, Florence, Italy
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13
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Lean M, Chacko B. The C3 conundrum. Intern Med J 2023; 53:1065-1069. [PMID: 37278101 DOI: 10.1111/imj.16111] [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: 01/02/2023] [Accepted: 03/01/2023] [Indexed: 06/07/2023]
Abstract
A 62-year-old man with nephritic syndrome underwent a kidney biopsy which revealed a C3 dominant pattern on immunofluorescence. A diagnosis of C3 glomerulopathy (C3G) was suspected. However, a recent skin infection and high levels of anti-streptococcal antibodies were indicative of post-infectious glomerulonephritis (PIGN). This paper compares PIGN and C3G and describes an atypical form of PIGN with alternative complement pathway dysregulation.
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Affiliation(s)
- Maria Lean
- Nephrology and Transplantation Unit, John Hunter Hospital, Newcastle, New South Wales, Australia
| | - Bobby Chacko
- Nephrology and Transplantation Unit, John Hunter Hospital, Newcastle, New South Wales, Australia
- School of Medicine and Public Health, University of Newcastle, Newcastle, New South Wales, Australia
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14
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Wada Y, Kamata M, Miyasaka R, Abe T, Kawamura S, Takeuchi K, Aoyama T, Oda T, Takeuchi Y. Clinico-Pathogenic Similarities and Differences between Infection-Related Glomerulonephritis and C3 Glomerulopathy. Int J Mol Sci 2023; 24:ijms24098432. [PMID: 37176142 PMCID: PMC10179079 DOI: 10.3390/ijms24098432] [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: 04/05/2023] [Revised: 04/26/2023] [Accepted: 05/01/2023] [Indexed: 05/15/2023] Open
Abstract
Recently, the comprehensive concept of "infection-related glomerulonephritis (IRGN)" has replaced that of postinfectious glomerulonephritis (PIGN) because of the diverse infection patterns, epidemiology, clinical features, and pathogenesis. In addition to evidence of infection, hypocomplementemia particularly depresses serum complement 3 (C3), with endocapillary proliferative and exudative GN developing into membranoproliferative glomerulonephritis (MPGN); also, C3-dominant or co-dominant glomerular immunofluorescence staining is central for diagnosing IRGN. Moreover, nephritis-associated plasmin receptor (NAPlr), originally isolated from the cytoplasmic fraction of group A Streptococci, is vital as an essential inducer of C3-dominant glomerular injury and is a key diagnostic biomarker for IRGN. Meanwhile, "C3 glomerulopathy (C3G)", also showing a histological pattern of MPGN due to acquired or genetic dysregulation of the complement alternative pathway (AP), mimics C3-dominant IRGN. Initially, C3G was characterized by intensive "isolated C3" deposition on glomeruli. However, updated definitions allow for glomerular deposition of other complement factors or immunoglobulins if C3 positivity is dominant and at least two orders of magnitude greater than any other immunoreactant, which makes it challenging to quickly distinguish pathomorphological findings between IRGN and C3G. As for NAPlr, it was demonstrated to induce complement AP activation directly in vitro, and it aggravates glomerular injury in the development of IRGN. A recent report identified anti-factor B autoantibodies as a contributing factor for complement AP activation in pediatric patients with PIGN. Moreover, C3G with glomerular NAPlr deposition without evidence of infection was reported. Taken together, the clinico-pathogenic features of IRGN overlap considerably with those of C3G. In this review, similarities and differences between the two diseases are highlighted.
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Affiliation(s)
- Yukihiro Wada
- Department of Nephrology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0374, Kanagawa, Japan
| | - Mariko Kamata
- Department of Nephrology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0374, Kanagawa, Japan
| | - Ryoma Miyasaka
- Department of Nephrology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0374, Kanagawa, Japan
| | - Tetsuya Abe
- Department of Nephrology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0374, Kanagawa, Japan
| | - Sayumi Kawamura
- Department of Nephrology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0374, Kanagawa, Japan
| | - Kazuhiro Takeuchi
- Department of Nephrology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0374, Kanagawa, Japan
| | - Togo Aoyama
- Department of Nephrology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0374, Kanagawa, Japan
| | - Takashi Oda
- Department of Nephrology and Blood Purification, Kidney Disease Center, Tokyo Medical University Hachioji Medical Center, Hachioji 193-0998, Tokyo, Japan
| | - Yasuo Takeuchi
- Department of Nephrology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0374, Kanagawa, Japan
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15
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Pisarenka S, Meyer NC, Xiao X, Goodfellow R, Nester CM, Zhang Y, Smith RJH. Modeling C3 glomerulopathies: C3 convertase regulation on an extracellular matrix surface. Front Immunol 2023; 13:1073802. [PMID: 36846022 PMCID: PMC9947773 DOI: 10.3389/fimmu.2022.1073802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 12/28/2022] [Indexed: 01/19/2023] Open
Abstract
Introduction C3 glomerulopathies (C3G) are ultra-rare complement-mediated diseases that lead to end-stage renal disease (ESRD) within 10 years of diagnosis in ~50% of patients. Overactivation of the alternative pathway (AP) of complement in the fluid phase and on the surface of the glomerular endothelial glycomatrix is the underlying cause of C3G. Although there are animal models for C3G that focus on genetic drivers of disease, in vivo studies of the impact of acquired drivers are not yet possible. Methods Here we present an in vitro model of AP activation and regulation on a glycomatrix surface. We use an extracellular matrix substitute (MaxGel) as a base upon which we reconstitute AP C3 convertase. We validated this method using properdin and Factor H (FH) and then assessed the effects of genetic and acquired drivers of C3G on C3 convertase. Results We show that C3 convertase readily forms on MaxGel and that this formation was positively regulated by properdin and negatively regulated by FH. Additionally, Factor B (FB) and FH mutants impaired complement regulation when compared to wild type counterparts. We also show the effects of C3 nephritic factors (C3Nefs) on convertase stability over time and provide evidence for a novel mechanism of C3Nef-mediated C3G pathogenesis. Discussion We conclude that this ECM-based model of C3G offers a replicable method by which to evaluate the variable activity of the complement system in C3G, thereby offering an improved understanding of the different factors driving this disease process.
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Affiliation(s)
- Sofiya Pisarenka
- Molecular Otolaryngology and Renal Research Laboratories, Caver College of Medicine, University of Iowa, Iowa City, IA, United States
- Molecular Medicine Graduate Program, Caver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Nicole C. Meyer
- Molecular Otolaryngology and Renal Research Laboratories, Caver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Xue Xiao
- Molecular Otolaryngology and Renal Research Laboratories, Caver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Renee Goodfellow
- Molecular Otolaryngology and Renal Research Laboratories, Caver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Carla M. Nester
- Molecular Otolaryngology and Renal Research Laboratories, Caver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Yuzhou Zhang
- Molecular Otolaryngology and Renal Research Laboratories, Caver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Richard J. H. Smith
- Molecular Otolaryngology and Renal Research Laboratories, Caver College of Medicine, University of Iowa, Iowa City, IA, United States
- Molecular Medicine Graduate Program, Caver College of Medicine, University of Iowa, Iowa City, IA, United States
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16
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Schubart A, Flohr S, Junt T, Eder J. Low-molecular weight inhibitors of the alternative complement pathway. Immunol Rev 2023; 313:339-357. [PMID: 36217774 PMCID: PMC10092480 DOI: 10.1111/imr.13143] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Dysregulation of the alternative complement pathway predisposes individuals to a number of diseases. It can either be evoked by genetic alterations in or by stabilizing antibodies to important pathway components and typically leads to severe diseases such as paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome, C3 glomerulopathy, and age-related macular degeneration. In addition, the alternative pathway may also be involved in many other diseases where its amplifying function for all complement pathways might play a role. To identify specific alternative pathway inhibitors that qualify as therapeutics for these diseases, drug discovery efforts have focused on the two central proteases of the pathway, factor B and factor D. Although drug discovery has been challenging for a number of reasons, potent and selective low-molecular weight (LMW) oral inhibitors have now been discovered for both proteases and several molecules are in clinical development for multiple complement-mediated diseases. While the clinical development of these inhibitors initially focuses on diseases with systemic and/or peripheral tissue complement activation, the availability of LMW inhibitors may also open up the prospect of inhibiting complement in the central nervous system where its activation may also play an important role in several neurodegenerative diseases.
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Affiliation(s)
- Anna Schubart
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Stefanie Flohr
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Tobias Junt
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Jörg Eder
- Novartis Institutes for BioMedical Research, Basel, Switzerland
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