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Mignano SE, Pascal V, Odioemene NE, Forehand W, Javaugue V, Said SM, Sethi S, Sirac C, Nasr SH. Monoclonal Immunoglobulin Crystalline Membranous Nephropathy. Am J Kidney Dis 2024; 84:120-125. [PMID: 38266972 DOI: 10.1053/j.ajkd.2023.11.011] [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: 07/17/2023] [Revised: 10/10/2023] [Accepted: 11/15/2023] [Indexed: 01/26/2024]
Abstract
Monoclonal immunoglobulin (MIg) crystalline nephropathies are rare lesions resulting from precipitation of MIgs in the kidney as intracellular or extracellular crystals. We describe a patient with multiple myeloma (IgGλ) and diabetes who presented with nephrotic range proteinuria. Kidney biopsy revealed membranous nephropathy superimposed on diabetic glomerulosclerosis. Glomeruli were negative for PLA2R, THSD7A, and NELL-1. Ultrastructurally, the subepithelial deposits were composed of crystals (ranging from rhomboid to rod to needle shaped), which failed to stain for immunoglobulins by routine immunofluorescence but stained for IgG+λ by paraffin immunofluorescence after pronase digestion. RNA-based immunoglobulin repertoire sequencing performed on bone marrow aspirate identified an IgGλ (γ1) clone, which was highly atypical, combining an extensively mutated (23.6%) Ig heavy chain derived from the IGHV1-24 with low pI and unusual mutations and a light chain derived from an extremely rare germline gene (IGLV10-54). This report expands the pathologic spectrum of MIg crystalline nephropathies by describing a unique case of crystalline nephropathy with IgGλ deposits manifesting as membranous nephropathy.
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Affiliation(s)
- Salvatore E Mignano
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Virginie Pascal
- Department of Immunology and Immunogenetics, Centre Hospitalier Universitaire de Limoges, Limoges, France; Control of the immune response B and lymphoproliferation, CNRS UMR 7276, INSERM UMR 1262, University of Limoges, Centre de référence de l'amylose AL et autres maladies par dépôts d'immunoglobuline monoclonale, Limoges, France
| | | | | | - Vincent Javaugue
- Control of the immune response B and lymphoproliferation, CNRS UMR 7276, INSERM UMR 1262, University of Limoges, Centre de référence de l'amylose AL et autres maladies par dépôts d'immunoglobuline monoclonale, Limoges, France; Service de néphrologie et Centre National de référence amylose AL et autres maladies à dépôts d'immunoglobulines monoclonales, Centre Hospitalier Universitaire, Université de Poitiers, Poitiers, France
| | - Samar M Said
- Department of Pathology, Olmsted County Medical Center, Rochester, Minnesota
| | - Sanjeev Sethi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Christophe Sirac
- Control of the immune response B and lymphoproliferation, CNRS UMR 7276, INSERM UMR 1262, University of Limoges, Centre de référence de l'amylose AL et autres maladies par dépôts d'immunoglobuline monoclonale, Limoges, France.
| | - Samih H Nasr
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota.
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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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Liang Y, Li Q, Zou Z, Huang B, Zhong N, Li C, Wang A, Chen Y, Tu S, Wan J. A Dynamic Prediction Model for Renal Progression in Primary Membranous Nephropathy. Int J Med Sci 2024; 21:1292-1301. [PMID: 38818472 PMCID: PMC11134588 DOI: 10.7150/ijms.95321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 04/30/2024] [Indexed: 06/01/2024] Open
Abstract
Objective: This study aimed to build and validate a practical web-based dynamic prediction model for predicting renal progression in patients with primary membranous nephropathy (PMN). Method: A total of 359 PMN patients from The First Affiliated Hospital of Fujian Medical University and 102 patients with PMN from The Second Hospital of Longyan between January 2018 to December 2023 were included in the derivation and validation cohorts, respectively. Renal progression was delineated as a decrease in eGFR of 30% or more from the baseline measurement at biopsy or the onset of End-Stage Renal Disease (ESRD). Multivariable Cox regression analysis was employed to identify independent prognostic factors. A web-based dynamic prediction model for renal progression was built and validated, and the performance was assessed using. An analysis of the receiver operating characteristic and the decision curve analysis. Results: In the derivation cohort, 66 (18.3%) patients experienced renal progression during the follow-up period (37.60 ± 7.95 months). The final prediction rule for renal progression included hyperuricemia (HR=2.20, 95%CI 1.26 to 3.86), proteinuria (HR=2.16, 95%CI 1.47 to 3.18), significantly lower serum albumin (HR=2.34, 95%CI 1.51 to 3.68) and eGFR (HR=1.96, 95%CI 1.47 to 2.61), older age (HR=1.85, 95%CI 1.28 to 2.61), and higher sPLA2R-ab levels (HR=2.08, 95%CI 1.43 to 3.18). Scores for each variable were calculated using the regression coefficients in the Cox model. The developed web-based dynamic prediction model, available online at http://imnpredictmodel1.shinyapps.io/dynnomapp, showed good discrimination (C-statistic = 0.72) and calibration (Brier score, P = 0.155) in the validation cohort. Conclusion: We developed a web-based dynamic prediction model that can predict renal progression in patients with PMN. It may serve as a helpful tool for clinicians to identify high-risk PMN patients and tailor appropriate treatment and surveillance strategies.
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Affiliation(s)
- Yufeng Liang
- Department of Nephrology, Blood Purification Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China
- Department of Nephrology, The Second Hospital of Longyan, Fujian 364000, China
| | - Qiu Li
- Department of Nephrology, The Second Hospital of Longyan, Fujian 364000, China
| | - Zhenhuan Zou
- Department of Nephrology, Blood Purification Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China
- Fujian Clinical Research Center for Metabolic Chronic Kidney Disease, The First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China
- Department of Nephrology, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China
| | - Binsan Huang
- Department of Nephrology, The Second Hospital of Longyan, Fujian 364000, China
| | - Nan Zhong
- Department of Orthopedics, The Second Hospital of Longyan, Fujian 364000, China
| | - Chenlun Li
- Department of Nephrology, The Second Hospital of Longyan, Fujian 364000, China
| | - Azhen Wang
- Department of Nephrology, The Second Hospital of Longyan, Fujian 364000, China
| | - Yongping Chen
- Department of Nephrology, The Second Hospital of Longyan, Fujian 364000, China
| | - Shuzhen Tu
- School of Mathematics and Information Engineering, Longyan University, Fujian, 364000, China
| | - Jianxin Wan
- Department of Nephrology, Blood Purification Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China
- Fujian Clinical Research Center for Metabolic Chronic Kidney Disease, The First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China
- Department of Nephrology, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China
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Sethi S, Fervenza FC. Membranous nephropathy-diagnosis and identification of target antigens. Nephrol Dial Transplant 2024; 39:600-606. [PMID: 37863839 DOI: 10.1093/ndt/gfad227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Indexed: 10/22/2023] Open
Abstract
Membranous nephropathy (MN) is a common cause of nephrotic syndrome in adults. MN is characterized by subepithelial accumulation of immune complexes along the glomerular basement membrane. The immune complexes are composed of immunoglobulin G and a target antigen. PLA2R is the target antigen in approximately 60% of MN cases, and MN is traditionally classified as PLA2R-positive or PLA2R-negative MN. Over the last 7 years, additional target antigens have been identified, which have specific disease associations, distinctive clinical and pathologic findings, and therapeutic implications. The newly discovered target antigens include NELL1, EXT1/EXT2, NCAM1, SEMA3B, PCDH7, FAT1, CNTN1, NTNG1, PCSK6 and NDNF. To group all these antigens into a generic 'PLA2R-negative' MN group is imprecise and un-informative. We propose a logical approach for detection of the target antigen which includes (i) currently available serology-based testing to detect anti-PLA2R and anti-THSD7A antibodies; and (ii) kidney biopsy testing to detect the target antigens. Determination of the antigen on kidney biopsy can be done by immunohistochemistry or immunofluorescence studies. Alternatively, laser capture microdissection (LCM) of glomeruli followed by mass spectrometry (MS) can be used to identify a target antigen. LCM/MS has the advantage of being a one-stop test and is particularly useful for detection of rare target antigens. At the current time, while it is possible to detect the newer antigens by immunohistochemistry/immunofluorescence/LCM/MS, serology-based tests to detect serum antibodies to the new antigens are not yet available. It is critical that serology-based tests should be developed not just for accurate diagnosis, but as a guide for treatment. We review the current methodology and propose an algorithm for diagnosis and detection of target antigens in MN that may shape the current practice in the future. Membranous nephropathy (MN) results from accumulation of subepithelial immune complexes along the glomerular basement membrane.PLA2R is the most common target antigen, but newly discovered target antigens have filled the void of PLA2R-negative MN.MN associated with the newly discovered target antigens have distinctive clinical and pathologic findings, treatment and prognostic implications. These include NELL1, EXT1/EXT2, NCAM1, PCDH7, SEMA3B, CNTN1, FAT1, NDNF and PCSK6.Immunohistochemistry/immunofluorescence methodology is currently in use for detecting target antigens in kidney biopsy tissue, although we anticipate laser capture microdissection of glomeruli followed by mass spectrometry will become available soon.Serologic testing is currently available for only detecting antibodies to PLA2R and THSD7A. It is critical that serologic tests become available for detecting antibodies to the newly discovered antigens.
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Affiliation(s)
- Sanjeev Sethi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
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Radhakrishnan Y, Zand L, Sethi S, Fervenza FC. Membranous nephropathy treatment standard. Nephrol Dial Transplant 2024; 39:403-413. [PMID: 37934599 DOI: 10.1093/ndt/gfad225] [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: 08/09/2023] [Indexed: 11/09/2023] Open
Abstract
Membranous nephropathy (MN) is characterized by deposition of immune complexes leading to thickening of glomerular basement membranes. Over time, the understanding of MN has evolved, with the identification of specific autoantibodies against novel podocyte antigens and the unraveling of intricate pathogenic pathways. Although the anti-CD20 monoclonal antibody rituximab is favored as part of the initial therapy in MN, a subgroup of MN patients may be resistant to rituximab necessitating the use of alternative agents such as cytotoxic therapies. In addition, newer agents such as novel anti-CD20 monoclonal antibodies, therapies targeting the CD38-positive plasma cells and anti-complement therapy are being studied in patients who are resistant to traditional treatment strategies. This manuscript furnishes a review of the novel developments in the pathophysiology of MN including the identification of target antigens and current treatment standards for MN, concentrating on evidenced-based interventions designed to attain remission and to prevent disease progression.
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Affiliation(s)
- Yeshwanter Radhakrishnan
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - Ladan Zand
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - Sanjeev Sethi
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Fernando C Fervenza
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
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Sethi S, Theis JD, Palma LM, Madden B. From Patterns to Proteins: Mass Spectrometry Comes of Age in Glomerular Disease. J Am Soc Nephrol 2024; 35:117-128. [PMID: 37749770 PMCID: PMC10786612 DOI: 10.1681/asn.0000000000000221] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 08/17/2023] [Indexed: 09/27/2023] Open
Abstract
Laser capture microdissection and mass spectrometry (LCM/MS) is a technique that involves dissection of glomeruli from paraffin-embedded biopsy tissue, followed by digestion of the dissected glomerular proteins by trypsin, and subsequently mass spectrometry to identify and semiquantitate the glomerular proteins. LCM/MS has played a crucial role in the identification of novel types of amyloidosis, biomarker discovery in fibrillary GN, and more recently discovery of novel target antigens in membranous nephropathy (MN). In addition, LCM/MS has also confirmed the role for complement proteins in glomerular diseases, including C3 glomerulopathy. LCM/MS is now widely used as a clinical test and considered the gold standard for diagnosis and typing amyloidosis. For the remaining glomerular diseases, LCM/MS has remained a research tool. In this review, we discuss the usefulness of LCM/MS in other glomerular diseases, particularly MN, deposition diseases, and diseases of complement pathways, and advocate more routine use of LCM/MS at the present time in at least certain diseases, such as MN, for target antigen detection. We also discuss the limitations of LCM/MS, particularly the difficulties faced from moving from a research-based technique to a clinical test. Nonetheless, the role of LCM/MS in glomerular diseases is expanding. Currently, LCM/MS may be used to identify the etiology in certain glomerular diseases, but in the future, LCM/MS can play a valuable role in determining pathways of complement activation, inflammation, and fibrosis.
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Affiliation(s)
- Sanjeev Sethi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Jason D. Theis
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Lilian M.P. Palma
- Pediatric Nephrology, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Benjamin Madden
- Mayo Clinic Proteomics Core, Mayo Clinic, Rochester, Minnesota
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Liu X, Zhao Y, Niu Y, Xie Q, Nie H, Jin Y, Zhang Y, Lu Y, Zhu S, Zuo W, Yu C. Urinary single-cell sequence analysis of the urinary macrophage in different outcomes of membranous nephropathy. Clin Kidney J 2023; 16:2405-2416. [PMID: 38046013 PMCID: PMC10689170 DOI: 10.1093/ckj/sfad132] [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: 09/15/2022] [Indexed: 12/05/2023] Open
Abstract
Background Great progress has been made in the diagnosis and treatment of membranous nephropathy (MN). However, a significant number of patients do not respond to immunosuppressive therapy and eventually progress to end-stage kidney disease. To investigate the mechanism of different outcome of MN, we performed single-cell sequencing to analyze the urine cells of patients with and without complete remission of MN. Methods Urine single-cell RNA sequencing was performed on 12 healthy controls (HC) and 15 patients with MN. The patients were divided into a complete remission group (CR, n = 9) and a no remission group (NR, n = 6). Results (i) Macrophages were the largest group in urine cells, comprising 48.02%, 68.96% and 20.95% in the HC, CR and NR groups, respectively. (ii) Urinary macrophages expressing FIColin-1 and S100 calcium-binding protein A8 were mainly found in the HC and CR groups, indicating that they were derived from bone marrow and peripheral blood, while the urinary macrophages expressing the regulator of G-protein signaling 1 (RGS1) and HLA-DPA1, mainly found in the NR group, were derived from renal resident macrophages. (iii) In healthy adults, urine macrophages expressed the metallothionein family, indicating that they can regulate anti-inflammatory and proinflammatory functions bidirectionally. In the CR group, the urine macrophages showed strong proinflammatory properties. In the NR group, the urinary macrophages mainly associated with the level of proteinuria and the impaired renal function. Conclusions Our study firstly delineated the differences in urinary cell maps between healthy individuals and MN patients with CR or NR outcomes. Not only the origin but also the function of urine macrophages were different in the HC, CR and NR groups.
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Affiliation(s)
- Xi Liu
- Department of Nephrology, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yu Zhao
- Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yangyang Niu
- Department of Nephrology, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Qionghong Xie
- Division of Nephrology, Huashan Hospital, and Nephrology Research Institute, Fudan University, Shanghai, China
| | - Hao Nie
- Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yun Jin
- Department of Nephrology, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yingying Zhang
- Department of Nephrology, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yuqiu Lu
- Department of Nephrology, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Saiya Zhu
- Department of Nephrology, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Wei Zuo
- Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Chen Yu
- Department of Nephrology, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
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Kawagoe M, Odajima K, Asakawa S, Nagura M, Arai S, Yamazaki O, Tamura Y, Ohashi R, Iwakura T, Yasuda H, Shibata S, Fujigaki Y. A Diagnostic and Therapeutic Dilemma Concerning Exostosin 1/Exostosin 2-associated Lupus-like Membranous Nephropathy with Positive Antinuclear Antibody in an Elderly Man with Various Immune Abnormalities. Intern Med 2023; 62:3187-3194. [PMID: 36948625 PMCID: PMC10686739 DOI: 10.2169/internalmedicine.1251-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 02/12/2023] [Indexed: 03/24/2023] Open
Abstract
Exostosin 1 (EXT1) and exostosin 2 (EXT2)-associated membranous nephropathy (MN) may be associated with active autoimmune disease. We encountered an elderly man who presented with EXT1/EXT2-associated lupus-like MN with full house immune deposits, monoclonal gammopathy of uncertain significance and Sjögren's syndrome. The patient exhibited various other immune abnormalities. Although he did not fulfill the criteria of clinical systemic lupus erythematosus (SLE), he met a stand-alone renal criterion of the Systemic Lupus International Collaborating Clinics (SLICC) 2012. Whether or not a stand-alone renal criterion with EXT1/EXT2 positivity, as in the present patient, can efficiently guide decisions regarding the diagnosis and treatment of SLE remains a clinical dilemma.
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Affiliation(s)
- Mika Kawagoe
- Department of Internal Medicine, Teikyo University School of Medicine, Japan
| | - Kohei Odajima
- Department of Internal Medicine, Teikyo University School of Medicine, Japan
| | - Shinichiro Asakawa
- Department of Internal Medicine, Teikyo University School of Medicine, Japan
| | - Michito Nagura
- Department of Internal Medicine, Teikyo University School of Medicine, Japan
| | - Shigeyuki Arai
- Department of Internal Medicine, Teikyo University School of Medicine, Japan
| | - Osamu Yamazaki
- Department of Internal Medicine, Teikyo University School of Medicine, Japan
| | - Yoshifuru Tamura
- Department of Internal Medicine, Teikyo University School of Medicine, Japan
| | - Ryuji Ohashi
- Department of Integrated Diagnostic Pathology, Nippon Medical School, Japan
| | - Takamasa Iwakura
- Department of Internal Medicine, Hamamatsu University School of Medicine, Japan
| | - Hideo Yasuda
- Department of Internal Medicine, Hamamatsu University School of Medicine, Japan
| | - Shigeru Shibata
- Department of Internal Medicine, Teikyo University School of Medicine, Japan
| | - Yoshihide Fujigaki
- Department of Internal Medicine, Teikyo University School of Medicine, Japan
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Deepthi RV, George S, Mathew G, Roy S, Bindra M, Rebekah G, Agarwal I. The Clinical Profile and Long-Term Outcome of Children with Membranous Nephropathy, and the Evaluation of Anti-Phospholipase A2 Receptor Antibody Immunohistochemistry in Kidney Biopsy. Indian J Nephrol 2023; 33:432-439. [PMID: 38174298 PMCID: PMC10752404 DOI: 10.4103/ijn.ijn_228_22] [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: 07/02/2022] [Revised: 10/11/2022] [Accepted: 11/02/2022] [Indexed: 01/05/2024] Open
Abstract
Introduction Idiopathic membranous nephropathy (iMN) is a rare cause of nephrotic syndrome in children (1%-7%). Anti-phospholipase A2 receptor (PLA2R) antibody positivity in kidney biopsy is observed in 52%-78% of adults and 45% of children with iMN. The objectives of the study are to analyze the clinical profile and outcome of membranous nephropathy in children, to assess the prevalence of anti-PLA2R immunohistochemistry (IHC) in kidney biopsy, and to correlate their presence with disease characteristics. Methods We are reporting a single-center retrospective study conducted in pediatric nephrology division. Clinical data and outcome parameters of children with membranous nephropathy were analyzed. PLA2R IHC was performed in kidney biopsy specimens retrospectively. Results We analyzed 43 children with membranous nephropathy (MN) from a single center. 18 (42%) had idiopathic MN (iMN). PLA2R IHC was performed in kidney biopsy specimens in 14/18 (78%) patients with iMN and 7/9 (78%) non-lupus secondary membranous nephropathy (SMN) patients. The most common cause of SMN was lupus nephritis in 16 patients (64%). The mean estimated glomerular filtration rate (eGFR) at onset was 156 ± 81 ml/min/1.73m2. The sensitivity and specificity of PLA2R IHC in diagnosing pediatric MN was 50% and 57%, respectively; positive and negative predictive values were 70% and 36%, respectively. At the final follow-up, chronic kidney disease stage 5 (CKD 5) developed in 2/14 (14.3%) iMN patients. Conclusions IHC PLA2R staining of glomerular tissue is a useful diagnostic marker of IMN. Though PLA2R prevalence is lower in children, its role in guiding treatment needs further exploration.
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Affiliation(s)
- RV Deepthi
- Departments of Child Health, Division of Pediatric Nephrology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Sachin George
- Departments of Child Health, Division of Pediatric Nephrology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Georgie Mathew
- Departments of Child Health, Division of Pediatric Nephrology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Sanjeet Roy
- Department of General Pathology, Division of Renal Pathology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Mandeep Bindra
- Consultant in Pathology, Naruvi Hospital, Vellore, Tamil Nadu, India
| | - Grace Rebekah
- Department of Biostatistics, Christian Medical College, Vellore, Tamil Nadu, India
| | - Indira Agarwal
- Departments of Child Health, Division of Pediatric Nephrology, Christian Medical College, Vellore, Tamil Nadu, India
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Nath KA, Erickson LA, Garovic VD. Primary and Secondary Diagnoses in Medicine: Insights From Mayo Clinic Consensus Report on Membranous Nephropathy--Executive Summary. Mayo Clin Proc 2023; 98:1599-1601. [PMID: 37804269 DOI: 10.1016/j.mayocp.2023.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 08/14/2023] [Indexed: 10/09/2023]
Affiliation(s)
- Karl A Nath
- Division of Nephrology & Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN.
| | - Lori A Erickson
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN
| | - Vesna D Garovic
- Division of Nephrology & Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN
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Caravaca-Fontán F, Yandian F, Fervenza FC. Future landscape for the management of membranous nephropathy. Clin Kidney J 2023; 16:1228-1238. [PMID: 37529655 PMCID: PMC10387398 DOI: 10.1093/ckj/sfad041] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Indexed: 08/03/2023] Open
Abstract
Among all glomerular diseases, membranous nephropathy (MN) is perhaps the one in which major progress has been made in recent decades, in both the understanding of the pathogenesis and treatment. Despite the overall significant response rates to these therapies-particularly rituximab and cyclical regimen based on corticosteroids and cyclophosphamide-cumulative experience over the years has shown, however, that 20%-30% of cases may confront resistant disease. Thus, these unmet challenges in the treatment of resistant forms of MN require newer approaches. Several emerging new agents-developed primarily for the treatment of hematological malignancies or rheumatoid diseases-are currently being evaluated in MN. Herein we conducted a narrative review on future therapeutic strategies in the disease. Among the different novel therapies, newer anti-CD20 agents (e.g. obinutuzumab), anti-CD38 (e.g. daratumumab, felzartamab), immunoadsorption or anti-complement therapies (e.g. iptacopan) have gained special attention. In addition, several technologies and innovations developed primarily for cancer (e.g. chimeric antigen receptor T-cell therapy, sweeping antibodies) seem particularly promising. In summary, the future therapeutic landscape in MN seems encouraging and will definitely move the management of this disease towards a more precision-based approach.
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Affiliation(s)
| | - Federico Yandian
- Department of Nephrology, Hospital de Clínicas “Dr Manuel Quintela”, Montevideo, Uruguay
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12
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Sethi S, Madden B, Casal Moura M, Singh RD, Nasr SH, Hou J, Sharma A, Nath KA, Specks U, Fervenza FC, Haas M. Membranous Nephropathy in Syphilis is Associated with Neuron-Derived Neurotrophic Factor. J Am Soc Nephrol 2023; 34:374-384. [PMID: 36857498 PMCID: PMC10103242 DOI: 10.1681/asn.0000000000000061] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 11/17/2022] [Indexed: 01/22/2023] Open
Abstract
SIGNIFICANCE STATEMENT Syphilis is a common worldwide sexually transmitted infection. Proteinuria may occur in patients with syphilis. Membranous nephropathy (MN) is the most common cause of proteinuria in syphilis. The target antigen of MN in syphilis is unknown. This study shows that MN in syphilis is associated with a novel target antigen called neuron-derived neurotrophic factor (NDNF). NDNF-associated MN has distinctive clinical and pathologic manifestations and NDNF appears to be the target antigen in syphilis-associated MN. BACKGROUND Syphilis is a common sexually transmitted infection. Membranous nephropathy (MN) is a common cause of proteinuria in syphilis. The target antigen is not known in most cases of syphilis-associated MN. METHODS We performed laser microdissection of glomeruli and mass spectrometry (MS/MS) in 250 cases (discovery cohort) of phospholipase A2 receptor-negative MN to identify novel target antigens. This was followed by immunohistochemistry/confocal microscopy to localize the target antigen along the glomerular basement membrane (GBM). Western blot analyses using IgG eluted from frozen biopsy tissue were performed to detect binding to target antigen. RESULTS MS/MS studies of the discovery cohort revealed high total spectral counts of a novel protein, neuron-derived neurotrophic factor (NDNF), in three patients: one each with syphilis and hepatitis B, HIV (syphilis status not known), and lung tumor. Next, MS/MS studies of five cases of syphilis-MN (validation cohort) confirmed high total spectral counts of NDNF (average 45±20.4) in all (100%) cases. MS/MS of 14 cases of hepatitis B were negative for NDNF. All eight cases of NDNF-associated MN were negative for known MN antigens. Electron microscopy showed stage I MN in all cases, with superficial and hump-like deposits without GBM reaction. IgG1 was the dominant IgG subtype on MS/MS and immunofluorescence microscopy. Immunohistochemistry/confocal microscopy showed granular staining and colocalization of NDNF and IgG along GBM. Western blot analyses using eluate IgG of NDNF-MN showed binding to both nonreduced and reduced NDNF, while IgG eluate from phospholipase A2 receptor-MN showed no binding. CONCLUSION NDNF is a novel antigenic target in syphilis-associated MN.
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Affiliation(s)
- Sanjeev Sethi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Benjamin Madden
- Mayo Clinic Proteomics Core, Mayo Clinic, Rochester, Minnesota
| | - Marta Casal Moura
- Division of Pulmonary and Critical Care, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Raman Deep Singh
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota
| | - Samih H. Nasr
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Jean Hou
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, California
| | - Alok Sharma
- Department of Renal Pathology & Electron Microscopy, Dr Lal Path Labs, New Delhi, India
| | - Karl A. Nath
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota
| | - Ulrich Specks
- Division of Pulmonary and Critical Care, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Fernando C. Fervenza
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota
| | - Mark Haas
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, California
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13
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Salvadori M, Tsalouchos A. Update on New Antigens in the Pathogenesis of Membranous Nephropathy. EUROPEAN MEDICAL JOURNAL 2022. [DOI: 10.33590/emj/22-00130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Previously, membranous nephropathies were divided into primary and secondary categories when the exact mechanism or pathogenetic factor were unknown.
Approximately 70% accounted for primary membranous nephropathies. The
remaining 30% were called secondary because they developed due to well-known
diseases such as autoimmune diseases, tumours, infections, or drug assumptions.
The discoveries of the M-type phospholipase A2 receptor and of thrombospondin
type 1 domain containing 7A as causative antigens in a part of the so-called primary
membranous nephropathies opened new knowledge on the effective causes of
a large part of these diseases. The availability of novel techniques such as laser
micro-dissection and tandem mass spectrometry, as well as immunochemistry with
antibodies directed against novel proteins, allowed the confirmation of new antigens
involved. The use of confocal microscopy and Western blot allowed detection of the
new antigen on glomerular membrane, and the same antigen and relative antibodies
have been detected in serum samples.
Through these techniques, four new antigens were first detected, including neural
epidermal growth factor 1 and semaphorin 3B in the so-called primary membranous
nephropathy, and exostosin 1 and 2 and neural cell adhesion molecule 1 in lupus
membranous nephropathy.
The aim of this study is to describe the characteristics of the new antigens
discovered and their association with other diseases. In addition, new antigens
are on the horizon, and the story of primary membranous nephropathy is still to be
completely written and understood.
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Affiliation(s)
| | - Aris Tsalouchos
- Division of Nephrology, Santa Maria Annunziata Hospital, Florence, Italy
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14
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Lin L, Tian E, Ren J, Wu Z, Deng J, Yang J. Traditional Chinese Medicine in Treating Primary Podocytosis: From Fundamental Science to Clinical Research. Front Pharmacol 2022; 13:932739. [PMID: 36003509 PMCID: PMC9393213 DOI: 10.3389/fphar.2022.932739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 06/23/2022] [Indexed: 11/30/2022] Open
Abstract
Podocytes form a key component of the glomerular filtration barrier. Damage to podocytes is referred to as “podocyte disease.” There are many causes of podocyte injury, including primary injury, secondary injury, and gene mutations. Primary podocytosis mostly manifests as nephrotic syndrome. At present, first-line treatment is based on glucocorticoid administration combined with immunosuppressive therapy, but some patients still progress to end-stage renal disease. In Asia, especially in China, traditional Chinese medicine (TCM) still plays an important role in the treatment of kidney diseases. This study summarizes the potential mechanism of TCM and its active components in protecting podocytes, such as repairing podocyte injury, inhibiting podocyte proliferation, reducing podocyte apoptosis and excretion, maintaining podocyte skeleton structure, and upregulating podocyte-related protein expression. At the same time, the clinical efficacy of TCM in the treatment of primary podocytosis (including idiopathic membranous nephropathy, minimal change disease, and focal segmental glomerulosclerosis) is summarized to support the development of new treatment strategies for primary podocytosis.
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Affiliation(s)
- Lirong Lin
- Department of Nephrology, The Third Affiliated Hospital of Chongqing Medical University (General Hospital), Chongqing, China
| | - En Tian
- Department of Nephrology, The Third Affiliated Hospital of Chongqing Medical University (General Hospital), Chongqing, China
| | - Jiangwen Ren
- Department of Nephrology, Rheumatism and Immunology, Jiulongpo District People’s Hospital of Chongqing, Chongqing, China
| | - Zhifeng Wu
- Department of Nephrology, The Third Affiliated Hospital of Chongqing Medical University (General Hospital), Chongqing, China
| | | | - Jurong Yang
- Department of Nephrology, The Third Affiliated Hospital of Chongqing Medical University (General Hospital), Chongqing, China
- *Correspondence: Jurong Yang,
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15
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Salvadori M, Tsalouchos A. New antigens involved in membranous nephropathy beyond phospholipase A2 receptor. World J Nephrol 2022; 11:115-126. [PMID: 36161266 PMCID: PMC9353762 DOI: 10.5527/wjn.v11.i4.115] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/24/2022] [Accepted: 07/11/2022] [Indexed: 02/06/2023] Open
Abstract
When the physiopathology of membranous nephropathy was first described, almost 30% of cases were recognized to be secondary to well-known diseases such as autoimmune diseases, tumors or infections. The remaining 70% cases were called primary membranous nephropathy as the exact mechanism or pathogenic factor involved was unknown. The discovery of the M type phospholipase A2 receptor and thrombospondin type 1 domain containing 7A as causative antigens in these “so called” primary membranous nephropathies provided new insights into the effective causes of a large proportion of these cases. Novel techniques such as laser microdissection and tandem mass spectrometry as well as immunochemistry with antibodies directed against novel proteins allowed the confirmation of new involved antigens. Finally, using confocal microscopy to localize these new antigens and immunoglobulin G and Western blot analysis of serum samples, these new antigens were detected on the glomerular membrane, and the related antibodies were detected in serum samples. The same antigens have been recognized in some cases of secondary membranous disease due to autoimmune diseases, tumors and infections. This has allowed examination of the relationship between antigens in primary membranous nephropathy and their presence in some secondary nephropathies. The aim of this study is to describe the characteristics of the new antigens discovered and their association with other diseases.
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Affiliation(s)
- Maurizio Salvadori
- Department of Renal Transplantation, Careggi University Hospital, Florence 50139, Tuscany, Italy
| | - Aris Tsalouchos
- Division of Nephrology, Santa Maria Annunziata, Florence 50012, Tuscany, Italy
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16
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Sethi S, Madden B, Casal Moura M, Nasr SH, Klomjit N, Gross L, Negron V, Charlesworth MC, Alexander MP, Leung N, Specks U, Fervenza FC, Haas M. Hematopoietic Stem Cell Transplant-Membranous Nephropathy Is Associated with Protocadherin FAT1. J Am Soc Nephrol 2022; 33:1033-1044. [PMID: 35321939 PMCID: PMC9063902 DOI: 10.1681/asn.2021111488] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/25/2022] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Membranous nephropathy (MN) is a common cause of proteinuria in patients receiving a hematopoietic stem cell transplant (HSCT). The target antigen in HSCT-associated MN is unknown. METHODS We performed laser microdissection and tandem mass spectrometry (MS/MS) of glomeruli from 250 patients with PLA2R-negative MN to detect novel antigens in MN. This was followed by immunohistochemical (IHC)/immunofluorescence (IF) microscopy studies to localize the novel antigen. Western blot analyses using serum and IgG eluted from frozen biopsy specimen to detect binding of IgG to new 'antigen'. RESULTS MS/MS detected a novel protein, protocadherin FAT1 (FAT1), in nine patients with PLA2R-negative MN. In all nine patients, MN developed after allogeneic HSCT (Mayo Clinic discovery cohort). Next, we performed MS/MS in five patients known to have allogeneic HSCT-associated MN (Cedar Sinai validation cohort). FAT1 was detected in all five patients by MS/MS. The total spectral counts for FAT1 ranged from 8 to 39 (mean±SD, 20.9±10.1). All 14 patients were negative for known antigens of MN, including PLA2R, THSD7A, NELL1, PCDH7, NCAM1, SEMA3B, and HTRA1. Kidney biopsy specimens showed IgG (2 to 3+) with mild C3 (0 to 1+) along the GBM; IgG4 was the dominant IgG subclass. IHC after protease digestion and confocal IF confirmed granular FAT1 deposits along the GBM. Lastly, Western blot analyses detected anti-FAT1 IgG and IgG4 in the eluate obtained from pooled frozen kidney biopsy tissue and in the serum of those with FAT1-asssociated MN, but not from those with PLA2R-associated MN. CONCLUSIONS FAT1-associated MN appears to be a unique type of MN associated with HSCT. FAT1-associated MN represents a majority of MN associated with HSCT.
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Affiliation(s)
- Sanjeev Sethi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Benjamin Madden
- Medical Genome Facility, Proteomics Core, Mayo Clinic, Rochester, Minnesota
| | - Marta Casal Moura
- Division of Pulmonary and Critical Care, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Samih H. Nasr
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Nattawat Klomjit
- Division of Nephrology and Hypertension, Department of Medicine, University of Minnesota, Minneapolis, Minnesota
| | - LouAnn Gross
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Vivian Negron
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | | | - Mariam P. Alexander
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Nelson Leung
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota
| | - Ulrich Specks
- Division of Pulmonary and Critical Care, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | | | - Mark Haas
- Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, California
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17
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Definition of IgG Subclass-Specific Glycopatterns in Idiopathic Membranous Nephropathy: Aberrant IgG Glycoforms in Blood. Int J Mol Sci 2022; 23:ijms23094664. [PMID: 35563055 PMCID: PMC9101794 DOI: 10.3390/ijms23094664] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/15/2022] [Accepted: 04/20/2022] [Indexed: 11/18/2022] Open
Abstract
The podocyte injury, and consequent proteinuria, that characterize the pathology of idiopathic membranous nephropathy (IMN) is mediated by an autoimmune reaction against podocyte antigens. In particular, the activation of pathways leading to abundant renal deposits of complement is likely to involve the binding of mannose-binding lectin (MBL) to aberrant glycans on immunoglobulins. To obtain a landscape of circulatory IgG Fc glycosylation characterizing this disease, we conducted a systematic N-glycan profiling study of IgG1, 2, and 4 by mass spectrometry. The cohort included 57 IMN patients, a pathological control group with nephrotic syndrome (PN) (n = 20), and 88 healthy control subjects. The effect of sex and age was assessed in all groups and controlled by rigorous matching. Several IgG Fc glycan traits were found to be associated with IMN. Interestingly, among them, only IgG4-related results were specific for IMN and not for PN. Hypo-galactosylation of IgG4, already shown for IMN, was observed to occur in the absence of core fucose, in line with a probable increase of pro-inflammatory IgG. In addition, elevated levels of fucosylated IgG4, along with low levels of hybrid-type glycans, were detected. Some of these IgG4 alterations are likely to be more pronounced in high PLA2R (phospholipase A2 receptor) patients. IgG Fc glycosylation patterns associated with IMN warrant further studies of their role in disease mechanisms and may eventually enrich the diagnostic spectrum regarding patient stratification.
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18
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Glassock RJ. Precision medicine for the treatment of glomerulonephritis: A bold goal but not yet a transformative achievement. Clin Kidney J 2021; 15:657-662. [PMID: 35371458 PMCID: PMC8967540 DOI: 10.1093/ckj/sfab270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Indexed: 11/13/2022] Open
Abstract
Abstract
The revolution in our ability to recognize the alterations in fundamental biology brought about by disease has fostered a renewed interest in precision or personalized medicine (“the right treatment, or diagnostic test, for the right patient at the right time”). This nascent field has been led by oncology, immune-hematology and infectious disease, but nephrology is catching up, and quickly. Specific forms of glomerulonephritis thought to represent specific “diseases” have been “downgraded” to “patterns of injury”. New entities have emerged through application of sophisticated molecular technologies; often embraced by the term “multi-omics”. Kidney biopsies are now interpreted by next generation imaging and machine learning. Many opportunities are manifest that will translate these remarkable developments into novel safe and effective treatment regimens for specific pathogenic pathways evoking glomerulonephritis and its progression to kidney failure. A few successes emboldens a positive look to the future. A sustained and highly collaborative engagement with this new paradigm will be required for this field, full of hope and high expectations, to realize its goal of transforming glomerular therapeutics from “one size fits all (or many)” to a true individualized management principle.
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Affiliation(s)
- Richard J Glassock
- Emeritus Professor, Department of Medicine, Geffen School of Medicine. Los Angeles, CA, USA
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19
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Sabiu G, Podestà MA. Membranous Nephropathy: It Is Time to Go Back to the Future. Nephron Clin Pract 2021; 145:721-727. [PMID: 34225270 DOI: 10.1159/000516984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 05/01/2021] [Indexed: 11/19/2022] Open
Abstract
CONTEXT Membranous nephropathy (MN) is an immune-mediated glomerular disease that can lead to nephrotic syndrome and progressive kidney function loss. The cyclic steroid-cyclophosphamide regimen (the modified Ponticelli protocol) and the monoclonal anti-CD20 antibody rituximab have been advocated as effective therapies to improve renal outcomes, but a direct comparison of these treatments had never been carried out in a prospective study. Subject of Review: Scolari et al. [J Am Soc Nephrol. 2021;32:972-82] recently reported the results of a pilot randomized controlled trial (RI-CYCLO) designed to provide direct estimates of the effect of rituximab (1 g × 2) compared to the cyclic steroid-cyclophosphamide regimen in 74 patients with MN. The proportion of patients with complete remission at 12 months was higher in the cyclic regimen arm than that of rituximab (32 and 16%, respectively), but the difference was not statistically significant in intention-to-treat analyses. Interestingly, differences in the cumulative incidence of complete and partial remissions between treatment arms progressively reduced over the follow-up and became virtually nonexistent from 24 months (>80% in both groups). The frequency of serious and nonserious adverse events was similar between the 2 treatment arms. Infusion reactions and drug discontinuation were more common with rituximab, while infections and leukopenia were more frequently observed with the cyclic regimen. The risk of cancer was similar in the 2 allocation groups, but the limited follow-up length did not allow to draw definitive conclusions. Independent of treatment allocation, 18% of patients experienced at least 1 relapse after achieving complete or partial remission. Second Opinion: Notwithstanding the intrinsic limitations of a pilot study, the RI-CYCLO trial represents an important milestone in the treatment of MN. Findings from this study support the hypothesis that the cyclic regimen and rituximab may have comparable efficacy in inducing disease remission over the long term. Considering its potentially better-albeit not yet formally proven-long-term safety profile, rituximab could be considered as a first-line therapy for most patients with MN. Several questions remain to be addressed, including rituximab ideal dose and its efficacy in patients with a significant reduction in glomerular filtration rate. In light of RI-CYCLO results, a large-scale trial to assess rituximab noninferiority to the cyclic regimen would require the enrollment of thousands of patients, and it would be probably unfeasible within a reasonable time frame. In our opinion, resources should be allocated to provide an answer to the pressing matter of treatment nonresponse and intolerance, which may be addressed in the near future with novel therapeutic strategies.
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Affiliation(s)
- Gianmarco Sabiu
- Nephrology Unit, ASST Fatebenefratelli Sacco, Department of Biomedical and Clinical Sciences "Luigi Sacco," University of Milan, Milan, Italy
| | - Manuel Alfredo Podestà
- Renal Division, ASST Santi Paolo e Carlo, Department of Health Sciences, University of Milan, Milan, Italy
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