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Wang Y, Shang S, Jiang S, Zou G, Gao H, Li W. Complement C3a/C3aR and C5a/C5aR deposits accelerate the progression of advanced IgA nephropathy to end-stage renal disease. Clin Exp Med 2024; 24:139. [PMID: 38951265 PMCID: PMC11217045 DOI: 10.1007/s10238-024-01410-3] [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: 05/05/2024] [Accepted: 06/19/2024] [Indexed: 07/03/2024]
Abstract
IgA nephropathy (IgAN) is still one of the leading causes of end-stage kidney disease (ESRD), and complement system activation is a key to the pathogenesis of IgAN. The role of complement C3a/C3aR and C5a/C5aR in late stage of IgAN remains unknown. Renal specimens of 75 IgAN patients at the stage 4 CKD were stained using immunofluorescence and immunohistochemistry. The primary outcome was a composite of end-stage renal disease (ESRD) and death. Associations of complement components with baseline clinicopathological characteristics and outcomes were assessed using multivariable Cox regression and Spearman analyses. During a median follow-up of 15.0 months, 27 patients progressed to ESRD and none died. Lower eGFR [hazards ratio (HR), 0.827, 95% confidence interval (CI), 0.732-0.935; P = 0.002] and glomerular C3 deposition (HR, 3.179, 95% CI, 1.079-9.363; P = 0.036) were predictive of time to ESRD in stage 4 CKD IgAN. Higher expression of C3a (P = 0.010), C3aR (P = 0.005), C5a (P = 0.015), and C5aR (P < 0.001) was identified in ESRD group than in non-ESRD group. Glomerular C3a/C3aR and C5a/C5aR deposits were both correlated with a lower baseline eGFR, higher baseline 24 h-urinary protein (24 h-UP) and faster decline of eGFR. Besides, C3a and C5a deposits were found in patients with high S (S1) and T (T1/2) scores, respectively. Complement C3a/C3aR and C5a/C5aR in IgAN patients with stage 4 CKD may portend a faster deterioration of kidney function.
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Affiliation(s)
- Ying Wang
- Department of Nephrology, China-Japan Friendship Hospital, No. 2 East Yinghuayuan Street, Chaoyang District, Beijing, 100029, China
| | - Shunlai Shang
- Department of Nephrology, China-Japan Friendship Hospital, No. 2 East Yinghuayuan Street, Chaoyang District, Beijing, 100029, China.
| | - Shimin Jiang
- Department of Nephrology, China-Japan Friendship Hospital, No. 2 East Yinghuayuan Street, Chaoyang District, Beijing, 100029, China
| | - Guming Zou
- Department of Nephrology, China-Japan Friendship Hospital, No. 2 East Yinghuayuan Street, Chaoyang District, Beijing, 100029, China
| | - Hongmei Gao
- Department of Nephrology, China-Japan Friendship Hospital, No. 2 East Yinghuayuan Street, Chaoyang District, Beijing, 100029, China
| | - Wenge Li
- Department of Nephrology, China-Japan Friendship Hospital, No. 2 East Yinghuayuan Street, Chaoyang District, Beijing, 100029, China.
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Reily C, Moldoveanu Z, Pramparo T, Hall S, Huang ZQ, Rice T, Novak L, Komers R, Jenkinson CP, Novak J. Sparsentan ameliorates glomerular hypercellularity and inflammatory-gene networks induced by IgA1-IgG immune complexes in a mouse model of IgA nephropathy. Am J Physiol Renal Physiol 2024; 326:F862-F875. [PMID: 38511222 DOI: 10.1152/ajprenal.00253.2023] [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: 08/22/2023] [Revised: 02/07/2024] [Accepted: 03/02/2024] [Indexed: 03/22/2024] Open
Abstract
IgA nephropathy (IgAN) is characterized by glomerular deposition of immune complexes (ICs) consisting of IgA1 with O-glycans deficient in galactose (Gd-IgA1) and Gd-IgA1-specific IgG autoantibodies. These ICs induce kidney injury, and in the absence of disease-specific therapy, up to 40% of patients with IgAN progress to kidney failure. IgA1 with its clustered O-glycans is unique to humans, which hampered development of small-animal models of IgAN. Here, we used a model wherein engineered ICs (EICs) formed from human Gd-IgA1 and recombinant human IgG autoantibody are injected into nude mice to induce glomerular injury mimicking human IgAN. In this model, we assessed the protective effects of sparsentan, a single-molecule dual endothelin angiotensin receptor antagonist (DEARA) versus vehicle on EIC-induced glomerular proliferation and dysregulation of gene expression in the kidney. Oral administration of sparsentan (60 or 120 mg/kg daily) to mice intravenously injected with EIC attenuated the EIC-induced glomerular hypercellularity. Furthermore, analysis of changes in the whole kidney transcriptome revealed that key inflammatory and proliferative biological genes and pathways that are upregulated in this EIC model of IgAN were markedly reduced by sparsentan, including complement genes, integrin components, members of the mitogen-activated protein kinase family, and Fc receptor elements. Partial overlap between mouse and human differentially expressed genes in IgAN further supported the translational aspect of the immune and inflammatory components from our transcriptional findings. In conclusion, our data indicate that in the mouse model of IgAN, sparsentan targets immune and inflammatory processes leading to protection from mesangial hypercellularity.NEW & NOTEWORTHY The mechanisms by which deposited IgA1 immune complexes cause kidney injury during early phases of IgA nephropathy are poorly understood. We used an animal model we recently developed that involves IgA1-IgG immune complex injections and determined pathways related to the induced mesangioproliferative changes. Treatment with sparsentan, a dual inhibitor of endothelin type A and angiotensin II type 1 receptors, ameliorated the induced mesangioproliferative changes and the associated alterations in the expression of inflammatory genes and networks.
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Affiliation(s)
- Colin Reily
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Zina Moldoveanu
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Tiziano Pramparo
- Travere Therapeutics Incorporated, San Diego, California, United States
| | - Stacy Hall
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Zhi-Qiang Huang
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Terri Rice
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Lea Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Radko Komers
- Travere Therapeutics Incorporated, San Diego, California, United States
| | - Celia P Jenkinson
- Travere Therapeutics Incorporated, San Diego, California, United States
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States
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Kang Y, Xu B, Shi S, Zhou X, Chen P, Liu L, Li Y, Leng Y, Lv J, Zhu L, Zhang H. Mesangial C3 Deposition, Complement-Associated Variant, and Disease Progression in IgA Nephropathy. Clin J Am Soc Nephrol 2023; 18:1583-1591. [PMID: 37651123 PMCID: PMC10723908 DOI: 10.2215/cjn.0000000000000290] [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: 04/17/2023] [Accepted: 08/25/2023] [Indexed: 09/01/2023]
Abstract
BACKGROUND IgA nephropathy is the most common primary GN worldwide, with dominant deposition of IgA and co-deposits of complement component 3 (C3). Phenotypes and progression of IgA nephropathy varies among different ethnic populations, while patients with IgA nephropathy from Asia showed more severe clinical phenotypes, active kidney lesions, and rapid progression. Our previous genome-wide association study identified complement factor H ( CFH ) variant rs6677604, tightly linked with the deletion of CFH -related protein 3 and CFH -related protein 1 genes ( ΔCFHR3-1 ), as IgA nephropathy susceptible variant, and additionally revealed its effect on complement regulation in IgA nephropathy. METHODS To further explore the effect of rs6677604 on IgA nephropathy progression, here we enrolled a Chinese IgA nephropathy cohort of 1781 patients with regular follow-up for analysis. The rs6677604 genotype was measured, and the genotype-phenotype correlation was analyzed using the t test, the chi-squared test, or the nonparametric test, and the association between rs6677604 genotype or mesangial C3 deposition and IgA nephropathy prognosis was analyzed using Kaplan-Meier analysis and Cox regression. RESULTS We found that patients with rs6677604-GG genotype had a stronger intensity of mesangial C3 deposition than those with the rs6677604-AA/AG genotype. Patients with IgA nephropathy who had stronger intensity of C3 deposition manifested with more severe clinical and pathological manifestations, including lower eGFR and higher Oxford-M/S/T/C (mesangial hypercellularity, endocapillary cellularity, segmental sclerosis, interstitial fibrosis/tubular atrophy, and crescent) scores. In the survival analysis, stronger intensity of mesangial C3 deposition, but not rs6677604-GG genotypes, was associated with poor long-term kidney outcome in IgA nephropathy. CONCLUSIONS We found that in Chinese patients with IgA nephropathy, variant rs6677604 was associated with mesangial C3 deposition, and mesangial C3 deposition, but not rs6677604, was associated with IgA nephropathy severity and progression.
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Affiliation(s)
- Yuqi Kang
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China; Peking University Institute of Nephrology, Beijing, China; Key Laboratory of Renal Disease (Peking University), Beijing, China; National Health Commission, Key Laboratory of Chronic Kidney Disease Prevention and Treatment, Ministry of Education, Beijing, China; and State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing, China
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Cetinkaya H, Gursu M, Yazici H, Cebeci E, Eren N, Altiparmak MR, Akcay OF, Sahin G, Dheir H, Basturk T, Atilgan KG, Aydemir N, Turgutalp K, Yilmaz M, Sirali SK, Tatar E, Boz EG, Mirioglu S, Kazan S, Aydin E, Aydin Z, Turkmen K, Kutlay S, Karagoz F, Ogutmen MB, Ozturk S, Ozkan O, Yildiz N, Dincer T, Yasar E, Gok M, Turkmen A, Dede F, Derici U. Could mesangial C3 deposition be an independent prognostic marker in immunoglobulin A nephropathy? J Nephrol 2023:10.1007/s40620-023-01770-1. [PMID: 37947938 DOI: 10.1007/s40620-023-01770-1] [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: 04/11/2023] [Accepted: 08/18/2023] [Indexed: 11/12/2023]
Abstract
BACKGROUND Immunoglobulin A nephropathy (IgAN) is a common primary glomerulonephropathy. There is evidence that mesangial C3 deposition plays a role in the development of the disease. The aim of this study was to examine the effect of C3 deposition on the prognosis of IgAN patients. METHOD The study included 1135 patients with biopsy-confirmed IgAN from the database of the Turkish Nephrology Association Glomerular Diseases Working Group (TSN-GOLD). Patients were excluded from the study if they were aged < 18 or > 75 years or if C3 staining had not been performed in the immunofluorescent analysis. C3 deposition was defined as an immunofluorescence intensity of C3 ≥ 2 + within the mesangium. The primary endpoints were the development of end-stage renal disease, a 30% decrease in glomerular filtration rate compared to the basal value or an elevation in proteinuria to a nephrotic level (3.5 gr/day). RESULTS Mesangial C3 deposition was observed in 603 (53.1%) patients. No statistically significant difference was found at baseline between the groups with and without mesangial C3 deposition, as for age, sex, BMI, proteinuria level, or the presence of hypertension. In the follow-up period with a mean duration of 78 months, no significant difference was found between the two groups regarding the primary endpoints (p = 0.43). A significant correlation between C3 deposition and segmental glomerulosclerosis (S1) according to the Oxford MEST-C classification was found (p = 0.001). CONCLUSION Although a correlation was observed between mesangial C3 deposition and the S1 MEST-C classification, mesangial C3 deposition was not a prognostic factor in IgAN.
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Affiliation(s)
- Hakki Cetinkaya
- Department of Nephrology, Sultan Abdulhamid Han Training and Research Hospital, University of Health Sciences, Istanbul, Turkey.
| | - Meltem Gursu
- Medical Faculty, Nephrology, Bezmialem Vakif University, Istanbul, Turkey
| | - Halil Yazici
- Istanbul Medical Faculty, Nephrology, Istanbul University, Istanbul, Turkey
| | - Egemen Cebeci
- Department of Nephrology, Haseki Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Necmi Eren
- Medical Faculty, Nephrology, Kocaeli University, Izmit, Kocaeli, Turkey
| | | | | | - Gulizar Sahin
- Department of Nephrology, Sultan Abdulhamid Han Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Hamad Dheir
- Medical Faculty, Nephrology, Sakarya University, Adapazari, Sakarya, Turkey
| | - Taner Basturk
- Department of Nephrology, Sisli Hamidiye Etfal Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Kadir Gokhan Atilgan
- Department of Nephrology, Diskapi Training and Research Hospital, University of Health Sciences, Ankara, Turkey
| | - Nihal Aydemir
- Department of Nephrology, Ankara Bilkent City Hospital, University of Health Sciences, Ankara, Turkey
| | - Kenan Turgutalp
- Division of Nephrology, Department of Internal Medicine, Mersin University School of Medicine, Mersin, Turkey
| | - Murvet Yilmaz
- Department of Nephrology, Bakirkoy Dr. Sadi Konuk Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Semahat Karahisar Sirali
- Department of Nephrology, Ankara Training and Research Hospital, University of Health Sciences, Ankara, Turkey
| | - Erhan Tatar
- Department of Nephrology, Bozyaka Training and Research Hospital, University of Health Sciences, Izmir, Turkey
| | - Elif Gullulu Boz
- Division of Nephrology, Department of Internal Medicine, Uludag University School of Medicine, Bursa, Turkey
| | - Safak Mirioglu
- Medical Faculty, Nephrology, Bezmialem Vakif University, Istanbul, Turkey
| | - Sinan Kazan
- Department of Nephrology, Afyonkarahisar School of Medicine, University of Health Sciences, Afyonkarahisar, Turkey
| | - Emre Aydin
- Medical Faculty, Nephrology, Dicle University, Diyarbakir, Turkey
| | - Zeki Aydin
- Department of Nephrology, Darica Farabi Training and Research Hospital, University of Health Sciences, Darica, Kocaeli, Turkey
| | - Kultigin Turkmen
- Meram Medical Faculty, Nephrology, Necmettin Erbakan University, Konya, Turkey
| | - Sim Kutlay
- Medical Faculty, Nephrology, Ankara University, Ankara, Turkey
| | - Ferdi Karagoz
- Medical Faculty, Nephrology, Trakya University, Edirne, Turkey
| | - Melike Betul Ogutmen
- Department of Nephrology, Haydarpasa Numune Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Savas Ozturk
- Istanbul Medical Faculty, Nephrology, Istanbul University, Istanbul, Turkey
| | - Oktay Ozkan
- Department of Nephrology, Haseki Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Nuriye Yildiz
- Medical Faculty, Nephrology, Kocaeli University, Izmit, Kocaeli, Turkey
| | - Tamer Dincer
- Cerrahpasa Medical Faculty, Nephrology, Istanbul University, Istanbul, Turkey
| | - Emre Yasar
- Medical Faculty, Nephrology, Gazi University, Ankara, Turkey
| | - Mahmut Gok
- Department of Nephrology, Sultan Abdulhamid Han Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Aydın Turkmen
- Istanbul Medical Faculty, Nephrology, Istanbul University, Istanbul, Turkey
| | - Fatih Dede
- Department of Nephrology, Ankara Bilkent City Hospital, University of Health Sciences, Ankara, Turkey
| | - Ulver Derici
- Medical Faculty, Nephrology, Gazi University, Ankara, Turkey
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Xiong L, Liu L, Tao Y, Guo H. Clinical significance of IgM and C3 deposition in children with primary immunoglobulin A nephropathy. J Nephrol 2023; 36:2213-2222. [PMID: 37542609 DOI: 10.1007/s40620-023-01724-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 06/30/2023] [Indexed: 08/07/2023]
Abstract
BACKGROUND Mesangial IgM and C3 deposition is commonly observed in patients with primary immunoglobulin A nephropathy (IgAN), but its characteristics and prognosis have rarely been reported. The aim of this study was to investigate the relationship between combined mesangial IgM and C3 deposition and disease progression in children with IgAN. METHODS One hundred sixteen children diagnosed with IgAN between 2016 and 2020 were selected. Renal biopsies were scored by Oxford classification including the presence of mesangial hypercellularity, endocapillary hypercellularity, segmental glomerulosclerosis, tubular atrophy/interstitial fibrosis and crescents. The primary renal outcome was an event of either ≥ 50% reduction of eGFR from the baseline value or the onset of end-stage renal disease within the follow-up period. Cox regression analysis was performed to examine the effect of the combined mesangial IgM and C3 deposition on renal outcomes. RESULTS Forty-seven (40.52%) patients presented combined mesangial IgM and C3 deposition. Compared with children without combined IgM and C3 deposition, children with combined IgM and C3 deposition presented higher mesangial hypercellularity, endocapillary hypercellularity and cresentic lesions in kidney biopsies, and higher prevalence of renal dysfunction (19.15% versus 2.90%; P = 0.007). Renal outcome was also significantly worse as revealed by Kaplan-Meier curves (P = 0.0034). Multivariable Cox analysis identified tubular atrophy/interstitial fibrosis lesions [hazard ratio (HR) 14.843, 95% CI, 3.497-62.997, P < 0.001] and intensity of IgM deposition (HR 2.838, 95% CI, 1.321-6.094, P = 0.007) as independent risk factors for poor renal function. CONCLUSIONS Combined mesangial IgM and C3 deposition was associated with unfavorable histopathological features. Mesangial IgM deposition was an independent risk factor for poor renal outcomes in children with primary IgAN.
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Affiliation(s)
- Limei Xiong
- Division of Nephrology, Department of Pediatrics, West China Second University Hospital, Sichuan University, NO. 20, Section 3, Renmin Nan Lu, Chengdu, 610041, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China
| | - Lili Liu
- Division of Nephrology, Department of Pediatrics, West China Second University Hospital, Sichuan University, NO. 20, Section 3, Renmin Nan Lu, Chengdu, 610041, China
| | - Yuhong Tao
- Division of Nephrology, Department of Pediatrics, West China Second University Hospital, Sichuan University, NO. 20, Section 3, Renmin Nan Lu, Chengdu, 610041, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China
| | - Hui Guo
- Division of Nephrology, Department of Pediatrics, West China Second University Hospital, Sichuan University, NO. 20, Section 3, Renmin Nan Lu, Chengdu, 610041, China.
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China.
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Hayashi A, Kawabe M, Yamamoto I, Ohki Y, Kobayashi A, Ueda H, Tanno Y, Urabe F, Miki J, Yamada H, Kimura T, Okido I, Tsuboi N, Yamamoto H, Yokoo T. Clinical and Pathological Significance of Mesangial C1q Deposition in Kidney Transplant Recipients with Recurrent IgA Nephropathy and Patients with Native IgA Nephropathy. Nephron Clin Pract 2023; 147 Suppl 1:80-88. [PMID: 37339606 DOI: 10.1159/000530916] [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: 12/14/2022] [Accepted: 03/22/2023] [Indexed: 06/22/2023] Open
Abstract
INTRODUCTION In kidney transplant recipients (KTRs) whose primary disease is IgA nephropathy (IgAN), IgAN recurrence occurs in approximately half of patients by 5 years postoperatively and is associated with graft survival. Although the alternative and lectin pathways are important in the primary pathogenesis of IgAN, the significance of mesangial C1q deposition, which triggers the classical pathway, is unknown. We investigated the clinicopathological significance of mesangial C1q deposition in both recurrent IgAN in KTRs and native IgAN. METHODS Between 2000 and 2021, we conducted a 1:2 matched case-control study of 18 KTRs diagnosed with recurrent IgAN, with a group of native IgAN patients as the control. We evaluated the rate and presence/absence of mesangial C1q deposition in terms of pathological findings and kidney outcomes in each group. RESULTS The rate of mesangial C1q deposition was significantly higher in the recurrent IgAN patients in KTRs than in native IgAN patients (11/18 [61.1%] vs. 5/36 [13.9%], p = 0.001). In the former group, the incidence of glomerular crescents was relatively higher in C1q-positive patients. There was no significant difference in the annual rate of estimated glomerular filtration rate decline between C1q-positive and C1q-negative patients in either group. CONCLUSION Mesangial C1q deposition was more frequent in KTRs with recurrent IgAN than in patients with native IgAN, but we found no difference in kidney outcomes with respect to mesangial C1q deposition. Further large-scale investigations of the importance of mesangial C1q deposition are needed in both KTRs with recurrent IgAN and patients with native IgAN.
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Affiliation(s)
- Ayaka Hayashi
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Mayuko Kawabe
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Izumi Yamamoto
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan,
| | - Yutaro Ohki
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Akimitsu Kobayashi
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroyuki Ueda
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Yudo Tanno
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Fumihiko Urabe
- Department of Urology, The Jikei University School of Medicine, Tokyo, Japan
| | - Jun Miki
- Department of Urology, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroki Yamada
- Department of Urology, The Jikei University School of Medicine, Tokyo, Japan
| | - Takahiro Kimura
- Department of Urology, The Jikei University School of Medicine, Tokyo, Japan
| | - Ichiro Okido
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Nobuo Tsuboi
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroyasu Yamamoto
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Takashi Yokoo
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
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Ohki Y, Kawabe M, Yamamoto I, Kobayashi A, Kanzaki G, Koike K, Ueda H, Tanno Y, Urabe F, Miki J, Yamada H, Kimura T, Ohkido I, Tsuboi N, Yamamoto H, Yokoo T. Early Recurrence of Immunoglobulin A Nephropathy after Kidney Transplantation in a Patient with Down Syndrome. Nephron Clin Pract 2023; 147 Suppl 1:35-40. [PMID: 37290422 DOI: 10.1159/000530915] [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: 12/09/2022] [Accepted: 04/04/2023] [Indexed: 06/10/2023] Open
Abstract
A 39-year-old male kidney transplant recipient with Down syndrome (DS) was admitted to our hospital for biopsy. He had proteinuria at age 9, was diagnosed with immunoglobulin A nephropathy (IgAN) at age 22, had a tonsillectomy at age 35, and underwent ABO-compatible kidney transplantation (from his mother) at age 36. His serum creatinine was stable at 2.21 mg/dL 3 months after the kidney transplant, and his urine protein was 0.11 g/day. A protocol biopsy was performed 7 months after the kidney transplant, and there was suspicion of early recurrence of IgAN. One year after the transplant, urine erythrocytes were elevated and proteinuria was 0.41 g/day; at 3 years and 5 months after the kidney transplant, hematuria was evident along with proteinuria (0.74 g/day). Therefore, an episode biopsy was performed. A total of 23 glomeruli were obtained, four of which exhibited global sclerosis; three others showed intra- and extracapillary proliferative glomerulonephritis compatible with IgAN recurrence. Here, we report a rare case of early recurrence of IgAN with disease progression despite tonsillectomy in a patient with DS.
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Affiliation(s)
- Yutaro Ohki
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Mayuko Kawabe
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Izumi Yamamoto
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Akimitsu Kobayashi
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Go Kanzaki
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Kentaro Koike
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroyuki Ueda
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Yudo Tanno
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Fumihiko Urabe
- Department of Urology, The Jikei University School of Medicine, Tokyo, Japan
| | - Jun Miki
- Department of Urology, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroki Yamada
- Department of Urology, The Jikei University School of Medicine, Tokyo, Japan
| | - Takahiro Kimura
- Department of Urology, The Jikei University School of Medicine, Tokyo, Japan
| | - Ichiro Ohkido
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Nobuo Tsuboi
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroyasu Yamamoto
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Takashi Yokoo
- Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
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Wang S, Dong L, Qin A, Tan J, Zhou X, Qin W. Roles of mesangial C3 and C1q deposition in the clinical manifestations and prognosis of IgAN. Int Immunopharmacol 2023; 120:110354. [PMID: 37235963 DOI: 10.1016/j.intimp.2023.110354] [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: 02/08/2023] [Revised: 05/06/2023] [Accepted: 05/14/2023] [Indexed: 05/28/2023]
Abstract
BACKGROUND AND AIM Immunoglobulin A nephropathy (IgAN) is regarded as the most common type of glomerulonephritis around the world and has the potential to result in renal failure. Complement activation has been addressed by a great body of evidence in the pathogenesis of IgAN. We aimed to evaluate the predictive value of C3 and C1q deposition for disease progression in IgAN patients in this retrospective study. METHODS We recruited 1191 biopsy-diagnosed IgAN patients, and they were divided into different groups according to their glomerular immunofluorescence examination of renal biopsy tissues: 1) C3 deposits ≥ 2 + group (N = 518) and C3 deposits < 2 + group (N = 673). 2) C1q deposit-positive group (N = 109) and C1q deposit-negative group (N = 1082). The renal outcomes were end-stage renal disease (ESRD) and/or an estimated glomerular filtration rate (eGFR) decrease greater than 50% from the baseline value. Kaplan-Meier analyses were performed to evaluate renal survival. Univariate and multivariate Cox proportional hazard regression models were used to evaluate the effect of C3 and C1q deposition on renal outcome in IgAN patients. In addition, we compared the predictive value of mesangial C3 and C1q deposition in IgAN patients. RESULTS The median follow-up period was 53 months (interquartile range 36-75 months). During follow-up, 7% (84) of patients progressed to ESRD, and 9% (111) of patients had an eGFR decline ≥ 50%. IgAN patients complicated with C3 deposits ≥ 2 + were associated with more severe renal dysfunction and pathologic lesions at the time of renal biopsy. The crude incidence rates for the endpoint were 12.5% (84 out of 673) and 17.2% (89 out of 518) in the C3 < 2 + and C3 ≥ 2 + groups, respectively (P = 0.022). Of C1q deposit-positive and C1q deposit-negative patients, 22.9% (25 out of 109) and 13.7% (148 out of 1082) reached the composite endpoint, respectively (P = 0.009). Adding C3 deposition to clinical and pathologic models had better predictability of renal disease progression than C1q. CONCLUSION Glomerular C3 and C1q deposits affected the clinicopathologic features of IgAN patients and emerged as independent predictors and risk factors for renal outcomes. In particular, the predictive ability of C3 was slightly better than that of C1q.
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Affiliation(s)
- Siqing Wang
- West China School of Medicine, Sichuan University, Chengdu, Sichuan, China; Division of Nephrology, Department of Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Lingqiu Dong
- West China School of Medicine, Sichuan University, Chengdu, Sichuan, China; Division of Nephrology, Department of Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Aiya Qin
- West China School of Medicine, Sichuan University, Chengdu, Sichuan, China; Division of Nephrology, Department of Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Jiaxing Tan
- West China School of Medicine, Sichuan University, Chengdu, Sichuan, China; Division of Nephrology, Department of Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Xiaoyuan Zhou
- West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Wei Qin
- West China School of Medicine, Sichuan University, Chengdu, Sichuan, China; Division of Nephrology, Department of Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
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9
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Kaga H, Matsumura H, Saito A, Saito M, Abe F, Suzuki T, Dohmae N, Odaka M, Komatsuda A, Wakui H, Takahashi N. Comparative proteomic analysis of glomerular proteins in IgA nephropathy and IgA vasculitis with nephritis. Clin Proteomics 2023; 20:21. [PMID: 37179321 PMCID: PMC10182656 DOI: 10.1186/s12014-023-09409-w] [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: 10/25/2022] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
BACKGROUND IgA nephropathy (IgAN) and IgA vasculitis with nephritis (IgAVN) are related glomerular diseases characterized by marked similarities in immunological and histological findings. We herein performed a comparative proteomic analysis of glomerular proteins in IgAN and IgAVN. METHODS We used renal biopsy specimens from 6 IgAN patients without nephrotic syndrome (NS) (IgAN-I subgroup), 6 IgAN patients with NS (IgAN-II subgroup), 6 IgAVN patients with 0-8.0% of glomeruli with crescent formation (IgAVN-I subgroup), 6 IgAVN patients with 21.2-44.8% of glomeruli with crescent formation (IgAVN-II subgroup), 9 IgAVN patients without NS (IgAVN-III subgroup), 3 IgAVN patients with NS (IgAN-IV subgroup), and 5 control cases. Proteins were extracted from laser microdissected glomeruli and analyzed using mass spectrometry. The relative abundance of proteins was compared between groups. An immunohistochemical validation study was also performed. RESULTS More than 850 proteins with high confidence were identified. A principal component analysis revealed a clear separation between IgAN and IgAVN patients and control cases. In further analyses, 546 proteins that were matched with ≥ 2 peptides were selected. The levels of immunoglobulins (IgA, IgG, and IgM), complements (C3, C4A, C5, and C9), complement factor H-related proteins (CFHR) 1 and 5, vitronectin, fibrinogen chains, and transforming growth factor-β inducible gene-h3 were higher (> 2.6 fold) in the IgAN and IgAVN subgroups than in the control group, whereas hornerin levels were lower (< 0.3 fold). Furthermore, C9 and CFHR1 levels were significantly higher in the IgAN group than in the IgAVN group. The abundance of some podocyte-associated proteins and glomerular basement membrane (GBM) proteins was significantly less in the IgAN-II subgroup than in the IgAN-I subgroup as well as in the IgAVN-IV subgroup than in the IgAVN-III subgroup. Among the IgAN and IgAVN subgroups, talin 1 was not detected in the IgAN-II subgroup. This result was supported by immunohistochemical findings. CONCLUSIONS The present results suggest shared molecular mechanisms for glomerular injury in IgAN and IgAVN, except for enhanced glomerular complement activation in IgAN. Differences in the protein abundance of podocyte-associated and GBM proteins between IgAN and IgAVN patients with and without NS may be associated with the severity of proteinuria.
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Affiliation(s)
- Hajime Kaga
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan
| | - Hirotoshi Matsumura
- Department of Life Science, Graduate School of Engineering Science, Akita University, Akita, Japan.
| | - Ayano Saito
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan
| | - Masaya Saito
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan
| | - Fumito Abe
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan
| | - Takehiro Suzuki
- Biomolecular Characterization Unit, RIKEN Center for Sustainable Resource Science, Wako, Japan
| | - Naoshi Dohmae
- Biomolecular Characterization Unit, RIKEN Center for Sustainable Resource Science, Wako, Japan
| | - Masafumi Odaka
- Department of Life Science, Graduate School of Engineering Science, Akita University, Akita, Japan
| | - Atsushi Komatsuda
- Department of Internal Medicine, Ogachi Central Hospital, Yuzawa, Japan
| | - Hideki Wakui
- Emeritus Professor, Akita University, Akita, Japan
| | - Naoto Takahashi
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan
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Demir S, Yet I, Sardan Ekiz M, Sag E, Bilginer Y, Celikbicak O, Lay I, Ozen S. Plasma Proteomic Analysis Reveals the Potential Role of Lectin and Alternative Complement Pathways in IgA Vasculitis Pathogenesis. Diagnostics (Basel) 2023; 13:diagnostics13101729. [PMID: 37238213 DOI: 10.3390/diagnostics13101729] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/08/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023] Open
Abstract
BACKGROUND IgA vasculitis (IgAV) is the most common form of childhood vasculitis. A better understanding of its pathophysiology is required to identify new potential biomarkers and treatment targets. OBJECTIVE to assess the underlying molecular mechanisms in the pathogenesis of IgAV using an untargeted proteomics approach. METHODS Thirty-seven IgAV patients and five healthy controls were enrolled. Plasma samples were collected on the day of diagnosis before any treatment was initiated. We used nano-liquid chromatography-tandem mass spectrometry (nLC-MS/MS) to investigate the alterations in plasma proteomic profiles. For the bioinformatics analyses, databases including Uniprot, PANTHER, KEGG, Reactome, Cytoscape, and IntAct were used. RESULTS Among the 418 proteins identified in the nLC-MS/MS analysis, 20 had significantly different expressions in IgAV patients. Among them, 15 were upregulated and 5 were downregulated. According to the KEGG pathway and function classification analysis, complement and coagulation cascades were the most enriched pathways. GO analyses showed that the differentially expressed proteins were mainly involved in defense/immunity proteins and the metabolite interconversion enzyme family. We also investigated molecular interactions in the identified 20 proteins of IgAV patients. We extracted 493 interactions from the IntAct database for the 20 proteins and used Cytoscape for the network analyses. CONCLUSION Our results clearly suggest the role of the lectin and alternate complement pathways in IgAV. The proteins defined in the pathways of cell adhesion may serve as biomarkers. Further functional studies may lead the way to better understanding of the disease and new therapeutic options for IgAV treatment.
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Affiliation(s)
- Selcan Demir
- Department of Pediatric Rheumatology, Hacettepe University Medical Faculty, 06230 Ankara, Turkey
| | - Idil Yet
- Department of Bioinformatics, Graduate School of Health Sciences, Hacettepe University, 06230 Ankara, Turkey
| | - Melis Sardan Ekiz
- Advanced Technologies Application and Research Center (HUNITEK), Hacettepe University, 06230 Ankara, Turkey
| | - Erdal Sag
- Department of Pediatric Rheumatology, Hacettepe University Medical Faculty, 06230 Ankara, Turkey
| | - Yelda Bilginer
- Department of Pediatric Rheumatology, Hacettepe University Medical Faculty, 06230 Ankara, Turkey
| | - Omur Celikbicak
- Department of Chemistry, Hacettepe University, 06230 Ankara, Turkey
| | - Incilay Lay
- Department of Biochemistry, Hacettepe University Medical Faculty, 06230 Ankara, Turkey
| | - Seza Ozen
- Department of Pediatric Rheumatology, Hacettepe University Medical Faculty, 06230 Ankara, Turkey
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11
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Xie M, Zhu Y, Wang X, Ren J, Guo H, Huang B, Wang S, Wang P, Liu Y, Liu Y, Zhang J. Predictive prognostic value of glomerular C3 deposition in IgA nephropathy. J Nephrol 2023; 36:495-505. [PMID: 35781866 DOI: 10.1007/s40620-022-01363-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 05/23/2022] [Indexed: 10/17/2022]
Abstract
BACKGROUND IgAN is the most common primary glomerulonephritis worldwide. However, the pathogenesis of IgAN remains unknown. Currently, there is evidence that C3 deposition plays a role in disease development. This study aimed to investigate clinical, pathological features, and prognosis of adult IgAN patients with C3 deposition, as well as explore the role of complement activation in disease progression. METHODS A total of 821 patients with biopsy-proven IgAN were included in this study. Patients were divided into three different groups according to their C3 deposition intensity. Clinical and pathological characteristics were compared between groups. Logistic analysis was used to estimate the relationship between C3 deposition and the Oxford scoring system. Univariate and multivariate Cox proportional hazard regression models were used to analyze the effect of the presence of C3 deposits on the prognosis of patients with IgA nephropathy. Kaplan-Meier survival analysis was used to evaluate the cumulative incidence of renal progression between groups. RESULTS Patients with C3 deposition exhibited more severe clinical and pathological features and had a higher score according to the Oxford scoring system. With the increasing intensity of C3 deposition, patients present more hematuria, crescents, heavier interstitial inflammatory cell infiltration and a higher score on segmental sclerosis lesions. Logistic regression identified a positive relationship between C3 deposition and histopathology. Univariate and multivariate Cox regression indicated that C3 deposition was an independent risk factor for IgAN severity. The Kaplan-Meier survival curves indicated that patients with positive C3 deposition had a worse prognosis compared to those without C3 deposition. CONCLUSIONS Patients with positive glomerular C3 deposition presented with more severe clinical and histopathological characteristics and a higher score on the Oxford scoring system. With the increasing intensity of C3 deposition, IgAN patients were more likely to present with high level of microscopic hematuria, fibrous crescents, interstitial inflammatory cell infiltration, and a higher score on segmental sclerosis lesions. C3 deposition at the time of renal biopsy is likely an independent risk factor for IgA nephropathy severity and progression.
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Affiliation(s)
- Minhua Xie
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Yuze Zhu
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Xutong Wang
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Jingjing Ren
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Haonan Guo
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Bo Huang
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Shulei Wang
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Peiheng Wang
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Yiming Liu
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Yingchun Liu
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China
| | - Junjun Zhang
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, Henan, China.
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12
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Podocytopathy Associated with IgA Nephropathy in Pregnancy: A Challenging Association. J Clin Med 2023; 12:jcm12051888. [PMID: 36902674 PMCID: PMC10004185 DOI: 10.3390/jcm12051888] [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: 01/17/2023] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 03/08/2023] Open
Abstract
IgA nephropathy is the most common form of primary glomerulonephritis. While associations of IgA and other glomerular diseases have been described, the association of IgA nephropathy with "primary" podocytopathy is rare and has not been reported in pregnancy, due in part to the infrequent use of kidney biopsy during pregnancy, and a frequent overlap with preeclampsia. We report the case of a 33-year-old woman with normal kidney function, referred in the 14th gestational week of her second pregnancy, due to nephrotic proteinuria and macroscopic hematuria. The baby's growth was normal. The patient reported episodes of macrohematuria one year previously. A kidney biopsy performed at 18 gestational weeks confirmed IgA nephropathy, associated with extensive podocyte damage. Treatment with steroids and tacrolimus led to remission of proteinuria and a healthy baby, adequate for gestational age, was delivered at 34 gestational weeks and 6 days (premature rupture of membranes). Six months after delivery, proteinuria was about 500 mg per day, with normal blood pressure and kidney function. This case highlights the importance of timely diagnosis in pregnancy and underlines that good maternal and fetal outcomes can be achieved with appropriate treatment, even in complex or severe cases.
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13
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Yang WG, Zhu R, Zheng JN, Zhang JX, Liu N, Yao L, Liu LL. Glomerular deposition of fibrinogen predicts good prognosis of IgA nephropathy: a single-center cohort study. Int Urol Nephrol 2023:10.1007/s11255-023-03501-8. [PMID: 36787086 DOI: 10.1007/s11255-023-03501-8] [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: 10/08/2021] [Accepted: 01/10/2023] [Indexed: 02/15/2023]
Abstract
PURPOSE It has been proven that fibrinogen deposition exists in IgA nephropathy (IgAN), but its clinical significance has not been identified. We aim to investigate the clinical implication of fibrinogen deposition in evaluating the activity and prognosis of IgA nephropathy. METHODS In this cohort, 935 adult IgAN patients were divided into 3 groups according to the intensity of glomerular fibrinogen deposition. Primary outcome refers to a composite event of either a ≥ 50% reduction in eGFR or ESRD (eGFR < 15 ml/min/1.73m2, dialysis, or renal transplantation). Factors associated with fibrinogen deposition and prognosis were identified. RESULTS The results showed that the intensity of fibrinogen deposition was positively correlated with eGFR (P < 0.001), serum albumin (P = 0.041), and hemoglobin levels (P < 0.05), but negatively correlated with age (P = 0.04), serum fibrinogen levels (P < 0.001), serum C4 (P = 0.023), the proportion of patients with hypertension (P = 0.003), and the percentage of glomeruli sclerosis (P < 0.001). The prognostic analyses identified that fibrinogen deposition was an independent predictor for the progression of IgAN (P = 0.033). CONCLUSION Our study indicated that the deposition of renal fibrinogen can predict the prognosis of IgAN with high reliability.
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Affiliation(s)
- Wei-Guang Yang
- Department of Nephrology, The First Affiliated Hospital of China Medical University, 155 Nan Jing North Street, He Ping District, Shen Yang, 110001, Liao Ning, China
| | - Rong Zhu
- Department of Nephrology, The First Affiliated Hospital of China Medical University, 155 Nan Jing North Street, He Ping District, Shen Yang, 110001, Liao Ning, China
| | - Jian-Nan Zheng
- Department of Nephrology, The First Affiliated Hospital of China Medical University, 155 Nan Jing North Street, He Ping District, Shen Yang, 110001, Liao Ning, China
| | - Jun-Xiao Zhang
- Department of Nephrology, The First Affiliated Hospital of China Medical University, 155 Nan Jing North Street, He Ping District, Shen Yang, 110001, Liao Ning, China
| | - Nan Liu
- Department of Nephrology, The First Affiliated Hospital of China Medical University, 155 Nan Jing North Street, He Ping District, Shen Yang, 110001, Liao Ning, China
| | - Li Yao
- Department of Nephrology, The First Affiliated Hospital of China Medical University, 155 Nan Jing North Street, He Ping District, Shen Yang, 110001, Liao Ning, China
| | - Lin-Lin Liu
- Department of Nephrology, The First Affiliated Hospital of China Medical University, 155 Nan Jing North Street, He Ping District, Shen Yang, 110001, Liao Ning, China.
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14
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Chen Y, Yang A, Hou Y, Liu L, Lin J, Huang X, Li J, Liu X, Lu F, Lin Q, Yang H, Yue S, Jiang S, Wang L, Zou C. Comparison between outcomes of IgA nephropathy with nephrotic-range proteinuria and nephrotic syndrome: do podocytes play a role? Ren Fail 2022; 44:1443-1453. [PMID: 36017686 PMCID: PMC9423834 DOI: 10.1080/0886022x.2022.2113796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Background Nephrotic syndrome (NS) and nephrotic-range proteinuria (NRP) are uncommon in IgA nephropathy (IgAN), and their clinicopathology and prognosis have not been discussed. Podocytes may play an important role in both clinical phenotypes. Methods We investigated 119 biopsy-proven IgAN patients with proteinuria over 2 g/d. The patients were divided into three groups according to proteinuria level: the overt proteinuria (OP) group, NS group, and NRP group. In addition, according to the severity of foot process effacement (FPE), the patients were divided into three groups: the segmental FPE (SFPE) group, moderate FPE (MFPE) group, and diffuse FPE (DFPE) group. The outcome was survival from a combined event defined by a doubling of the baseline serum creatinine and a 50% reduction in eGFR or ESRD. Results Compared with the NRP group, patients in the NS group had more severe microscopic hematuria, presented with more severe endocapillary hypercellularity and had a higher percentage of DFPE. The Kaplan–Meier curve showed that MFPE patients had a better outcome in the NRP group <50% of tubular atrophy/interstitial fibrosis. In the multivariate model, the NRP group (HR = 17.098, 95% CI = 3.835–76.224) was associated with an increased risk of the combined event, while MFPE (HR = 0.260, 95% CI = 0.078–0.864; p = 0.028) was associated with a reduced risk of the combined event. After the addition of renin-angiotensin system inhibitors (RASi), the incidence of the combined event in the MFPE group (HR = 0.179, 95% CI = 0.047–0.689; p = 0.012) was further reduced. Conclusions NS presented more active lesions and more severe FPE in IgAN. NRP was an independent risk factor for progression to the renal endpoint, while MFPE indicated a better prognosis in NRP without obvious chronic renal lesions, which may benefit from RASi.
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Affiliation(s)
- Yizhen Chen
- Second Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Aicheng Yang
- Department of Nephrology, The Affiliated Jiangmen TCM Hospital of Jinan University, Jiangmen, China
| | - Yuansheng Hou
- Second Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Longhui Liu
- Department of Nephrology, The Affiliated Jiangmen TCM Hospital of Jinan University, Jiangmen, China
| | - Jiehua Lin
- Department of Nephrology, The Affiliated Jiangmen TCM Hospital of Jinan University, Jiangmen, China
| | - Xiaodan Huang
- Second Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jundu Li
- Second Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xusheng Liu
- Department of Nephrology, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.,State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Fuhua Lu
- Department of Nephrology, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.,Guangdong-Hong Kong-Macau Joint Lab on Chinese Medicine and Immune Disease Research, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qizhan Lin
- Department of Hemodialysis, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Haifeng Yang
- Department of Pathology, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Shuling Yue
- Guangzhou Kingmed Diagnostic Laboratory Ltd, Guangzhou, China
| | - Shujun Jiang
- Department of Hemodialysis, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Lixin Wang
- Department of Nephrology, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Chuan Zou
- Department of Nephrology, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
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Matsumoto Y, Aryal RP, Heimburg-Molinaro J, Park SS, Wever WJ, Lehoux S, Stavenhagen K, van Wijk JAE, Van Die I, Chapman AB, Chaikof EL, Cummings RD. Identification and characterization of circulating immune complexes in IgA nephropathy. SCIENCE ADVANCES 2022; 8:eabm8783. [PMID: 36306365 PMCID: PMC9616497 DOI: 10.1126/sciadv.abm8783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 09/12/2022] [Indexed: 05/14/2023]
Abstract
The underlying pathology of immunoglobulin A (IgA) nephropathy (IgAN), the most common glomerulonephritis worldwide, is driven by the deposition of immune complexes containing galactose-deficient IgA1 [Tn(+)IgA1] in the glomerular mesangium. Here, we report that novel anti-Tn circulating immune complexes (anti-Tn CICs) contain predominantly IgM, representing large macromolecular complexes of ~1.2 megadaltons to several megadalton sizes together with Tn(+)IgA1 and some IgG. These complexes are significantly elevated in sera of patients with IgAN, which contains higher levels of complement C3, compared to healthy individuals. Anti-Tn CICs are bioactive and induce specific proliferation of human renal mesangial cells. We found that these anti-Tn CICs can be dissociated with small glycomimetic compounds, which mimic the Tn antigen of Tn(+)IgA1, releasing IgA1 from anti-Tn CICs. This glycomimetic compound can also significantly inhibit the proliferative activity of anti-Tn CICs of patients with IgAN. These findings could enhance both the diagnosis of IgAN and its treatment, as specific drug treatments are now unavailable.
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Affiliation(s)
- Yasuyuki Matsumoto
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Rajindra P. Aryal
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Jamie Heimburg-Molinaro
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Simon S. Park
- Department of Surgery, Center for Drug Discovery and Translational Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Wyss Institute of Biologically Inspired Engineering, Harvard University, Boston, MA, USA
| | - Walter J. Wever
- Department of Surgery, Center for Drug Discovery and Translational Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Wyss Institute of Biologically Inspired Engineering, Harvard University, Boston, MA, USA
| | - Sylvain Lehoux
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Kathrin Stavenhagen
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Joanna A. E. van Wijk
- Department of Pediatric Nephrology, Amsterdam University Medical Centre, location VUmc, Amsterdam, Netherlands
| | - Irma Van Die
- Department of Molecular Cell Biology and Immunology, Amsterdam University Medical Centre, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Arlene B. Chapman
- Department of Medicine, Section of Nephrology, University of Chicago School of Medicine, Chicago, IL, USA
| | - Elliot L. Chaikof
- Department of Surgery, Center for Drug Discovery and Translational Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Wyss Institute of Biologically Inspired Engineering, Harvard University, Boston, MA, USA
| | - Richard D. Cummings
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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Mitarai Y, Nakashima K, Fukunaga S, Ishikawa N, Ito T, Tsubata Y, Isobe T. IgA Nephropathy that Developed as an Immune-related Adverse Event of Pembrolizumab Complicated with Interstitial Nephritis. Intern Med 2022; 61:2013-2017. [PMID: 34840226 PMCID: PMC9334229 DOI: 10.2169/internalmedicine.7115-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
A 70-year-old man received pembrolizumab as a second-line treatment for squamous cell lung cancer of the lower right lobe. After three courses, proteinuria and hematuria were observed, which worsened after seven courses. He was diagnosed with a combination of IgA nephropathy and active interstitial nephritis. Steroid pulse therapy was started, and the dose of prednisolone was gradually reduced from 60 mg/day. Renal dysfunction as an immune-related adverse event of pembrolizumab monotherapy for non-small cell lung cancer has been reported previously. Therefore, establishing a system for the early detection and treatment that distinguishes immune-related glomerular diseases is essential.
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Affiliation(s)
- Yuki Mitarai
- Department of Respiratory Medicine, National Hospital Organization Hamada Medical Center, Japan
- Department of Internal Medicine, Division of Medical Oncology & Respiratory Medicine, Shimane University Faculty of Medicine, Japan
| | - Kazuhisa Nakashima
- Department of Internal Medicine, Division of Medical Oncology & Respiratory Medicine, Shimane University Faculty of Medicine, Japan
| | - Shohei Fukunaga
- Division of Nephrology, Shimane University Faculty of Medicine, Japan
| | | | - Takafumi Ito
- Division of Nephrology, Shimane University Faculty of Medicine, Japan
| | - Yukari Tsubata
- Department of Internal Medicine, Division of Medical Oncology & Respiratory Medicine, Shimane University Faculty of Medicine, Japan
| | - Takeshi Isobe
- Department of Internal Medicine, Division of Medical Oncology & Respiratory Medicine, Shimane University Faculty of Medicine, Japan
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Tsushima H, Samejima KI, Eriguchi M, Uemura T, Tasaki H, Fukata F, Nishimoto M, Kosugi T, Tanabe K, Okamoto K, Matsui M, Tsuruya K. The association of 5-year therapeutic responsiveness with long-term renal outcome in IgA nephropathy. Clin Exp Nephrol 2022; 26:797-807. [DOI: 10.1007/s10157-022-02221-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 03/29/2022] [Indexed: 11/30/2022]
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Clr-f expression regulates kidney immune and metabolic homeostasis. Sci Rep 2022; 12:4834. [PMID: 35318366 PMCID: PMC8940912 DOI: 10.1038/s41598-022-08547-9] [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: 11/19/2021] [Accepted: 03/09/2022] [Indexed: 11/25/2022] Open
Abstract
The C-type lectin-related protein, Clr-f, encoded by Clec2h in the mouse NK gene complex (NKC), is a member of a family of immune regulatory lectins that guide immune responses at distinct tissues of the body. Clr-f is highly expressed in the kidney; however, its activity in this organ is unknown. To assess the requirement for Clr-f in kidney health and function, we generated a Clr-f-deficient mouse (Clr-f−/−) by targeted deletions in the Clec2h gene. Mice lacking Clr-f exhibited glomerular and tubular lesions, immunoglobulin and C3 complement protein renal deposits, and significant abdominal and ectopic lipid accumulation. Whole kidney transcriptional profile analysis of Clr-f−/− mice at 7, 13, and 24 weeks of age revealed a dynamic dysregulation in lipid metabolic processes, stress responses, and inflammatory mediators. Examination of the immune contribution to the pathologies of Clr-f−/− mouse kidneys identified elevated IL-12 and IFNγ in cells of the tubulointerstitium, and an infiltrating population of neutrophils and T and B lymphocytes. The presence of these insults in a Rag1−/−Clr-f−/− background reveals that Clr-f−/− mice are susceptible to a T and B lymphocyte-independent renal pathogenesis. Our data reveal a role for Clr-f in the maintenance of kidney immune and metabolic homeostasis.
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Freiwald T, Afzali B. Renal diseases and the role of complement: Linking complement to immune effector pathways and therapeutics. Adv Immunol 2021; 152:1-81. [PMID: 34844708 PMCID: PMC8905641 DOI: 10.1016/bs.ai.2021.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The complement system is an ancient and phylogenetically conserved key danger sensing system that is critical for host defense against pathogens. Activation of the complement system is a vital component of innate immunity required for the detection and removal of pathogens. It is also a central orchestrator of adaptive immune responses and a constituent of normal tissue homeostasis. Once complement activation occurs, this system deposits indiscriminately on any cell surface in the vicinity and has the potential to cause unwanted and excessive tissue injury. Deposition of complement components is recognized as a hallmark of a variety of kidney diseases, where it is indeed associated with damage to the self. The provenance and the pathophysiological role(s) played by complement in each kidney disease is not fully understood. However, in recent years there has been a renaissance in the study of complement, with greater appreciation of its intracellular roles as a cell-intrinsic system and its interplay with immune effector pathways. This has been paired with a profusion of novel therapeutic agents antagonizing complement components, including approved inhibitors against complement components (C)1, C3, C5 and C5aR1. A number of clinical trials have investigated the use of these more targeted approaches for the management of kidney diseases. In this review we present and summarize the evidence for the roles of complement in kidney diseases and discuss the available clinical evidence for complement inhibition.
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Affiliation(s)
- Tilo Freiwald
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Bethesda, MD, United States; Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany
| | - Behdad Afzali
- Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany.
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Zhang Z, Zhang Y, Zhang H. IgA Nephropathy: A Chinese Perspective. GLOMERULAR DISEASES 2021; 2:30-41. [PMID: 36751266 PMCID: PMC9677733 DOI: 10.1159/000520039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 10/01/2021] [Indexed: 11/19/2022]
Abstract
Background IgA nephropathy (IgAN) is the most common primary glomerular disease worldwide and remains a leading cause of chronic kidney disease and end-stage renal disease. The disease prevalence, clinical and pathological phenotypes, the underlying pathogenic molecular mechanisms, and the response to treatments are highly heterogeneous in different ethnic populations, which raise the concern that IgAN may differ across different parts of the world. Summary From a Chinese perspective, we stated the disease burden of IgAN, summarized genome-wide association studies and research into pathological molecules, and compared them with findings based on other populations. The emerging biomarkers, indigenous clinical trials, and major challenges for Chinese researchers and nephrologists in studying IgAN are also discussed. Key Messages In this review, we described a higher risk of major susceptible loci in mucosal immunity, IgA production, and complement activation pathways in Chinese patients with IgAN. With our understanding of the pathogenesis of IgAN, novel biomarkers are emerging. Although there are challenges for conducting high-quality clinical trials in China, it is still feasible to conduct innovative and well-designed studies of IgAN. In the future, international collaborations on research infrastructure would be helpful to advance clinical and basic research in China.
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Affiliation(s)
- Zhao Zhang
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China,Institute of Nephrology, Peking University, Beijing, China,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China,Key Laboratory of Chronic Kidney Disease Prevention and Treatment, Peking University, Ministry of Education, Beijing, China
| | - Yuemiao Zhang
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China,Institute of Nephrology, Peking University, Beijing, China,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China,Key Laboratory of Chronic Kidney Disease Prevention and Treatment, Peking University, Ministry of Education, Beijing, China
| | - Hong Zhang
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China,Institute of Nephrology, Peking University, Beijing, China,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China,Key Laboratory of Chronic Kidney Disease Prevention and Treatment, Peking University, Ministry of Education, Beijing, China,*Hong Zhang,
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21
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Mesangial IgM deposition predicts renal outcome in patients with IgA nephropathy: a multicenter, observational study. Clin Exp Med 2021; 21:599-610. [PMID: 33837881 DOI: 10.1007/s10238-021-00703-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 03/12/2021] [Indexed: 02/05/2023]
Abstract
Mesangial IgM deposition is found in patients with immunoglobulin A nephropathy (IgAN). This study aims to investigate the relationships between mesangial IgM deposition and disease progression in IgAN patients. A total of 1239 patients with biopsy-proven primary IgAN were enrolled in this multicenter, observational study between January 2013 and August 2017. According to the degree of IgM deposition, 1239 patients were divided into three groups: Grade 0 (no or trace; n = 713, 57.55%), Grade 1 (mild; n = 414, 33.41%), Grades 2 + 3 (moderate and marked; n = 112, 9.04%). Using a 1:1 propensity score matching (PSM) method identifying age, gender and treatment modality to minimize confounding factors, 1042 matched patients (out of 1239) with different degrees of IgM deposition were enrolled to evaluate the severity of baseline clinicopathological features and renal outcome: Grade 0 (n = 521, 50.00%), Grade 1 (n = 409, 39.25%), Grades 2 + 3 (n = 112, 10.75%). Kaplan-Meier and Cox proportional hazards analyses were performed to determine whether different degrees of mesangial IgM deposition are associated with varying renal outcomes in IgAN. During a mean follow-up of 48.90 ± 23.86 and 49.01 ± 23.73 months, before and after adjusting for propensity scores, respectively, the rate of complete remission (CR) was progressively lower with increased IgM deposition in both unmatched (63.39%, 46.14%, 45.54%) and matched cohort (61.80%, 46.45%, 45.54%), whereas the proportion of patients progressing to end-stage renal disease (ESRD) showed reverse correlation (P < 0.001). Kaplan-Meier analysis indicated negative correlation between the intensity of mesangial IgM deposits and cumulative renal survival (all P < 0.05). Moreover, Cox regression analysis revealed that the degree of mesangial IgM deposition predicted renal outcome independent of MESTC score and clinical variables in the unmatched (Grade 1, HR, 1.59; 95% CI, 1.11-2.29; P = 0.01; Grades 2 + 3, HR, 1.69; 95% CI, 1.02-2.08; P = 0.04) and matched cohort (Grade 1, HR, 1.84; 95% CI, 1.19-2.85; P = 0.01; Grades 2 + 3, HR, 1.91; 95% CI, 1.01-3.24; P = 0.04). Mesangial IgM deposition is associated with histological activity, clinical severity and renal outcome and is an independent risk factor for poor renal prognosis in IgAN. TRIAL REGISTRATION: TCTR, TCTR20140515001. Registered May 15, 2014, http://www.clinicaltrials.in.th/index.php?tp=regtrials&menu=trialsearch&smenu=fulltext&task=search&task2=view1&id=1074 .
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22
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Shima Y, Nakanishi K, Mukaiyama H, Tanaka Y, Wada T, Tanaka R, Kaito H, Nozu K, Sako M, Iijima K, Yoshikawa N. Clinicopathological significance of glomerular capillary IgA deposition in childhood IgA nephropathy. Pediatr Nephrol 2021; 36:899-908. [PMID: 33011820 DOI: 10.1007/s00467-020-04772-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/26/2020] [Accepted: 09/09/2020] [Indexed: 12/29/2022]
Abstract
BACKGROUND IgA nephropathy (IgAN) is characterized by predominant mesangial IgA deposition. Some patients with IgAN demonstrate IgA deposition in glomerular peripheral capillaries (cap-IgA). The clinicopathological significance of cap-IgA remains incompletely investigated in children. METHODS We retrospectively analyzed 503 consecutive cases of biopsy-proven childhood IgAN between July 1976 and June 2013 to compare clinical and pathological features between IgAN patients with and without cap-IgA. RESULTS Among the 503 patients, 30 (6.0%) had cap-IgA. We found significant differences in proteinuria (2.0 vs. 0.5 g/day/m2, p < 0.0001), time from onset to kidney biopsy (2.2 vs. 8.3 months, p < 0.0001), and rate of proteinuria remission after treatment (23.3% vs. 48.0%, p = 0.007) between both groups. Pathological analysis revealed significant differences in M1 (83.3% vs. 56.0%, p = 0.002), ratio of subendothelial electron dense deposits (EDDs, 58.6% vs. 16.5%, p < 0.0001) and subepithelial EDDs (48.3% vs. 16.5%, p = 0.0001), and glomerular basement membrane (GBM) lysis (58.6% vs. 27.1%, p = 0.0006) between both groups. More than half of cap-IgA patients (17/30, 56.7%), whereas only 26.2% of non-cap-IgA patients (124/473), were treated with immunosuppressive treatments. Six of 30 cases (20%) with cap-IgA reached glomerular filtration rate (GFR) categories G3a-G5 (estimated GFR < 60 ml/min/1.73 m2) at most recent observation (mean observation period: 7.0 ± 4.0 years). According to Kaplan-Meier analysis, patients with cap-IgA had significantly lower kidney survival curves than non-cap-IgA patients (72.8% vs. 97.2% at 10 years, p < 0.0001). CONCLUSIONS Cap-IgA is associated with acute inflammation with GBM changes, resulting in refractory heavier proteinuria. Cap-IgA may represent a poor prognostic factor.
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Affiliation(s)
- Yuko Shima
- Department of Pediatrics, Wakayama Medical University, Wakayama City, Wakayama, Japan
| | - Koichi Nakanishi
- Department of Pediatrics, Child Health and Welfare (Pediatrics), Graduate School of Medicine, University of the Ryukyus, 207 Uehara Nishihara-cho, Nakagami-gun, Okinawa, 903-0125, Japan.
| | - Hironobu Mukaiyama
- Department of Pediatrics, Wakayama Medical University, Wakayama City, Wakayama, Japan
| | - Yu Tanaka
- Department of Pediatrics, Wakayama Medical University, Wakayama City, Wakayama, Japan
| | - Takuzo Wada
- Department of Pediatrics, Wakayama Medical University, Wakayama City, Wakayama, Japan
| | - Ryojiro Tanaka
- Department of Nephrology, Hyogo Prefectural Kobe Children's Hospital, Kobe, Hyogo, Japan
| | - Hiroshi Kaito
- Department of Nephrology, Hyogo Prefectural Kobe Children's Hospital, Kobe, Hyogo, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Mayumi Sako
- Division for Clinical Trials, Clinical Research Center, National Center for Child Health and Development, Tokyo, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Norishige Yoshikawa
- Clinical Research Center, Takatsuki General Hospital, Takatsuki City, Osaka, Japan
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Wu J, Hu Z, Wang Y, Hu D, Yang Q, Li Y, Dai W, Zhu F, Yang J, Wang M, Zhu H, Liu L, He X, Han M, Yao Y, Pei G, Zeng R, Xu G. Severe glomerular C3 deposition indicates severe renal lesions and a poor prognosis in patients with immunoglobulin A nephropathy. Histopathology 2021; 78:882-895. [PMID: 33336446 DOI: 10.1111/his.14318] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 11/23/2020] [Accepted: 12/16/2020] [Indexed: 01/04/2023]
Abstract
AIMS Glomerular complement 3 (C3) deposition is often observed in renal biopsies of patients with IgA nephropathy (IgAN); however, the relationship between the intensity of C3 deposition and the long-term prognosis of IgAN has rarely been reported. In this retrospective study, we aimed to evaluate the prognostic value of glomerular C3 deposition for IgAN progression. METHODS AND RESULTS From June 2009 to June 2010, a total of 136 adult patients with IgAN were enrolled in the study. According to the intensity of glomerular C3 deposition, patients were divided into a glomerular C3high group (34 patients) and a glomerular C3low group (102 patients). The levels of clinical parameters, glomerular immune complexes, histopathological features, and serum cytokines of the two groups were compared. On the basis of an average of 105 months of follow-up, the predictive value of glomerular C3 deposition for IgAN progression was also investigated. Patients in the C3high group had more severe glomerular IgA, IgG, IgM, and complement factor H deposition, a higher percentage of mesangial hypercellularity (M1), and higher levels of segmental glomerulosclerosis (S1), tubular atrophy/interstitial fibrosis (T2), and crescents (C2) than those in the C3low group. Renal biopsies in the C3high group showed higher densities of interstitial inflammatory cells and higher levels of serum interferon-γ than those in the C3low group. Multivariate Cox regression analysis revealed that a higher intensity of glomerular C3 deposition remained as an independent predictor of serum creatinine doubling and end-stage renal disease. CONCLUSIONS A high intensity of glomerular C3 deposition is associated with the severity of renal lesions, and predicts long-term poor renal survival for IgAN patients.
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Affiliation(s)
- Jianliang Wu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Zhizhi Hu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yuxi Wang
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Danni Hu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Qian Yang
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yueqiang Li
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Wei Dai
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Fengming Zhu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Juan Yang
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Meng Wang
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Han Zhu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Liu Liu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaofeng He
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Min Han
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Ying Yao
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Guangchang Pei
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Rui Zeng
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Gang Xu
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
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Wu L, Liu D, Xia M, Chen G, Liu Y, Zhu X, Liu H. Immunofluorescence deposits in the mesangial area and glomerular capillary loops did not affect the prognosis of immunoglobulin a nephropathy except C1q:a single-center retrospective study. BMC Nephrol 2021; 22:43. [PMID: 33514328 PMCID: PMC7845044 DOI: 10.1186/s12882-021-02237-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 01/11/2021] [Indexed: 02/08/2023] Open
Abstract
Background Immunoglobulin A nephropathy (IgAN) is identified as mesangial IgA deposition and is usually accompanied by other immunofluorescence deposits. The impact of immunofluorescent features in IgAN patients, however, remains unclear. Methods Baseline clinicopathologic parameters and renal outcomes of 337 patients diagnosed with IgAN between January 2009 and December 2015 were analyzed. We then categorized these patients into four groups: without immunofluorescence deposits, mesangial-only, mesangial and glomerular capillary loops (GCLs), and GCLs-only. The study endpoint was end-stage kidney disease (ESKD) or a ≥ 50% decline in the estimated glomerular filtration rate (eGFR). Kaplan–Meier and Cox regression analyses were performed to calculate renal survival. Results Of the 337 IgAN patients, women comprised 57.0%. Compared to patients with IgA deposition in the mesangial-only group, patients with IgA deposition in the mesangial +GCLs group were much heavier, and exhibited higher systolic blood pressure, lower serum IgG levels, and heavier proteinuria (all P < 0.05). Patients with IgG deposition in the mesangial +GCLs group presented with higher levels of cholesterol, heavier proteinuria than IgG deposition in the mesangial-only group (both P < 0.05). Compared with the mesangial-only group exhibiting C3 deposits, patients in the mesangial +GCLs group with C3 deposition had a higher systolic blood pressure (P = 0.028). A total of 38 patients (11.3%) continued to the study endpoint after a median follow-up time of 63.5 months (range,49.8–81.4). Kaplan–Meier analysis and Cox regression analysis showed that C1q deposition in the mesangial +GCLs group predicted a poor renal prognosis. Conclusions IgA and IgG deposits in the mesangial region and GCLs were associated with more unfavorable clinical and histopathologic findings in IgAN patients. C1q deposition in the mesangial region and GCLs predicted a poor renal prognosis. However, the impact of the pattern of immunofluorescence deposits on renal outcomes remains to be proven by further investigation.
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Affiliation(s)
- Lingzhi Wu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan, China.,Hunan Key Laboratory of Kidney Disease and Blood Purification, 139 Renmin Road, Changsha, 410011, Hunan, China
| | - Di Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan, China.,Hunan Key Laboratory of Kidney Disease and Blood Purification, 139 Renmin Road, Changsha, 410011, Hunan, China
| | - Ming Xia
- Department of Nephrology, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan, China.,Hunan Key Laboratory of Kidney Disease and Blood Purification, 139 Renmin Road, Changsha, 410011, Hunan, China
| | - Guochun Chen
- Department of Nephrology, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan, China.,Hunan Key Laboratory of Kidney Disease and Blood Purification, 139 Renmin Road, Changsha, 410011, Hunan, China
| | - Yu Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan, China.,Hunan Key Laboratory of Kidney Disease and Blood Purification, 139 Renmin Road, Changsha, 410011, Hunan, China
| | - Xuejing Zhu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan, China.,Hunan Key Laboratory of Kidney Disease and Blood Purification, 139 Renmin Road, Changsha, 410011, Hunan, China
| | - Hong Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan, China. .,Hunan Key Laboratory of Kidney Disease and Blood Purification, 139 Renmin Road, Changsha, 410011, Hunan, China.
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25
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Complement activation is associated with crescent formation in IgA nephropathy. Virchows Arch 2020; 477:565-572. [PMID: 32300880 DOI: 10.1007/s00428-020-02800-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 03/11/2020] [Accepted: 03/18/2020] [Indexed: 12/21/2022]
Abstract
IgA nephropathy (IgAN) is common chronic glomerulonephritis with variable prognosis, ranging from minor urinary abnormalities to end-stage renal disease. The revised Oxford classification of IgAN explains that cellular/fibrocellular crescents are associated with poor renal prognosis, proposing an extension to the MEST-C score. C3 immunofluorescent staining follows a distribution similar to IgA staining. Therefore, complement activation was reported to play a pivotal role in IgAN pathogenesis. This study included 132 IgAN patients diagnosed by renal biopsies. The clinical parameters at the time of the biopsies were obtained from patient data records. We classified the patients into C ≥ 1 and C0 groups, and compared clinical, light microscopic, and immunofluorescent features. In the C ≥ 1 group, 2 (1.5%) and 31 (23.5%) patients were assigned to C2 and C1, respectively. The remaining 99 patients (75%) were classified as C0. The C ≥ 1 group had lower average age and rate of hypertension, and higher score of urinary occult blood and E score. The C ≥ 1 group had significantly higher average immunofluorescence scores for IgA, C5b-9, mannose-associated serine protease (MASP) 1/3, MASP2, properdin, factor B, and kappa. The steroid use rate was significantly higher in the C ≥ 1 group. During the follow-up period of 2.90 years on average, the rate of renal dysfunction was not significantly different between groups. Crescent formation in IgAN was associated with activation of the lectin and alternative pathways. The C ≥ 1 group had significantly increased use of steroids, which probably caused comparable renal function during the follow-up period.
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Chang S, Li XK. The Role of Immune Modulation in Pathogenesis of IgA Nephropathy. Front Med (Lausanne) 2020; 7:92. [PMID: 32266276 PMCID: PMC7105732 DOI: 10.3389/fmed.2020.00092] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 03/03/2020] [Indexed: 01/10/2023] Open
Abstract
IgA nephropathy (IgAN) is the most prevalent primary glomerulonephritis worldwide, with diverse clinical manifestations characterized by recurrent gross hematuria or microscopic hematuria, and pathological changes featuring poorly O-galactosylated IgA1 deposition in the glomerular mesangium. Pathogenesis has always been the focus of IgAN studies. After 50 years of research, most scholars agree that IgAN is a group of clinicopathological syndromes with certain common immunopathological characteristics, and multiple mechanisms are involved in its pathogenesis, including immunology, genetics, and environmental or nutritional factors. However, the precise pathogenetic mechanisms have not been fully determined. One hypothesis about the pathogenesis of IgAN suggests that immunological factors are engaged in all aspects of IgAN development and play a critical role. A variety of immune cells (e.g., dendritic cells, NK cells, macrophages, T-lymphocyte subsets, and B-lymphocytes, etc.) and molecules (e.g., IgA receptors, Toll-like receptors, complements, etc.) in innate and adaptive immunity are involved in the pathogenesis of IgAN. Moreover, the abnormality of mucosal immune regulation is the core of IgAN immunopathogenesis. The roles of tonsil immunity or intestinal mucosal immunity, which have received more attention in recent years, are supported by mounting evidence. In this review, we will explore the latest research insights on the role of immune modulation in the pathogenesis of IgAN. With a better understanding of immunopathogenesis of IgAN, emerging therapies will soon become realized.
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Affiliation(s)
- Sheng Chang
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Key Laboratory of Organ Transplantation, Ministry of Education NHC Key Laboratory of Organ Transplantation Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, China.,Division of Transplantation Immunology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Xiao-Kang Li
- Division of Transplantation Immunology, National Research Institute for Child Health and Development, Tokyo, Japan.,Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Neufeld M, Molyneux K, Pappelbaum KI, Mayer-Hain S, von Hodenberg C, Ehrchen J, Barratt J, Suzuki Y, Sunderkötter C. Galactose-deficient IgA1 in skin and serum from patients with skin-limited and systemic IgA vasculitis. J Am Acad Dermatol 2019; 81:1078-1085. [PMID: 30902725 DOI: 10.1016/j.jaad.2019.03.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 03/02/2019] [Accepted: 03/10/2019] [Indexed: 11/25/2022]
Abstract
BACKGROUND IgA vasculitis (IgAV) encompasses a systemic form involving kidneys, gut, skin, or joints, and a skin-limited form. One characteristic feature of systemic IgAV is deposition of galactose-deficient IgA1 (GD-IgA1) in kidneys (as in IgA nephropathy). The relevance of GD-IgA1 for cutaneous vasculitis is unknown. OBJECTIVE We investigated whether GD-IgA1 is deposited perivascularly in systemic and also skin-limited IgAV and whether its serum levels differ between both forms. METHODS In a case-control study, deposition of GD-IgA1 was analyzed immunohistochemically by KM55 antibody in skin biopsy specimens from 12 patients with skin-limited IgAV and 4 with systemic IgAV. GD-IgA1 levels were compared by enzyme-linked immunosorbent assay in sera from 15 patients each with skin-limited and systemic IgAV and from 11 healthy individuals. RESULTS All biopsy samples from systemic IgAV, and also from skin-limited IgAV, revealed perivascular GD-IgA1 deposition. The average GD-IgA1 concentration in serum was significantly higher in systemic IgAV than in skin-limited IgAV, despite overlap between the groups. LIMITATIONS Although high GD-IgA1 levels may be predictive of systemic IgAV, patient numbers were too low to determine cutoff values for systemic versus skin-limited IgAV. CONCLUSION Perivascular GD-IgA1 deposition is a prerequisite for systemic and skin-limited IgAV; however, high GD-IgA1 levels in some patients with systemic IgAV suggest a dose-dependent effect of GD-IgA1 in IgAV.
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Affiliation(s)
- Matthias Neufeld
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany; Department of Dermatology, University of Münster, Münster, Germany
| | - Karen Molyneux
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Karin I Pappelbaum
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany
| | - Sarah Mayer-Hain
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany
| | - Christina von Hodenberg
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany; Department of Dermatology, University of Münster, Münster, Germany
| | - Jan Ehrchen
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany; Department of Dermatology, University of Münster, Münster, Germany
| | - Jonathan Barratt
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Yusuke Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Cord Sunderkötter
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany; Department of Dermatology and Venereology, University Hospital of Halle, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany.
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Rizk DV, Maillard N, Julian BA, Knoppova B, Green TJ, Novak J, Wyatt RJ. The Emerging Role of Complement Proteins as a Target for Therapy of IgA Nephropathy. Front Immunol 2019; 10:504. [PMID: 30941137 PMCID: PMC6433978 DOI: 10.3389/fimmu.2019.00504] [Citation(s) in RCA: 100] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 02/25/2019] [Indexed: 12/28/2022] Open
Abstract
IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis worldwide and a common cause of end-stage renal disease. Evaluation of a kidney biopsy is necessary for diagnosis, with routine immunofluorescence microscopy revealing dominant or co-dominant IgA immunodeposits usually with complement C3 and sometimes IgG and/or IgM. IgA nephropathy reduces life expectancy by more than 10 years and leads to kidney failure in 20–40% of patients within 20 years of diagnosis. There is accumulating clinical, genetic, and biochemical evidence that complement plays an important role in the pathogenesis of IgA nephropathy. The presence of C3 differentiates the diagnosis of IgA nephropathy from the subclinical deposition of glomerular IgA. Markers for the activation of the alternative and mannan-binding lectin (MBL) pathways in renal-biopsy specimens are associated with disease activity and portend a worse renal outcome. Complement proteins in the circulation have also been evaluated in IgA nephropathy and found to be of prognostic value. Recently, genetic studies have identified IgA nephropathy-associated loci. Within these loci are genes encoding products involved in complement regulation and interaction with immune complexes. Put together, these data identify the complement cascade as a rational treatment target for this chronic kidney disease. Recent case reports on the successful use of humanized anti-C5 monoclonal antibody eculizumab are consistent with this hypothesis, but a better understanding of the role of complement in IgA nephropathy is needed to guide future therapeutic interventions.
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Affiliation(s)
- Dana V Rizk
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Nicolas Maillard
- Department of Nephrology, Dialysis, Transplantation, CHU de Saint-Etienne, GIMAP, EA3064, Université Jean Monnet, COMUE Université de Lyon, Rhône-Alpes, France
| | - Bruce A Julian
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Barbora Knoppova
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States.,Department of Immunology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czechia
| | - Todd J Green
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Robert J Wyatt
- Department of Pediatrics, University of Tennessee Health Sciences Center, Memphis, TN, United States
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