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Komatsu H, Fujimoto S, Sato Y, Yasuda T, Yasuda Y, Matsuzaki K, Hirano K, Kawamura T, Yokoo T, Suzuki Y, Maruyama S. Effect of tonsillectomy combined with steroid pulse therapy upon IgA nephropathy depending on proteinuria status at diagnosis: a nationwide multicenter cohort study in Japan. Clin Exp Nephrol 2024:10.1007/s10157-024-02530-6. [PMID: 38954311 DOI: 10.1007/s10157-024-02530-6] [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: 02/13/2024] [Accepted: 06/16/2024] [Indexed: 07/04/2024]
Abstract
BACKGROUND The effects of tonsillectomy combined with steroid pulse (TSP) therapy for IgA nephropathy (IgAN) are little known. Therefore, we examined the effects of TSP therapy on the kidney outcomes of IgAN in a large, nationwide cohort study in Japan. METHODS Between 2002 and 2004, 632 IgAN patients with ≥ 0.5 g/day proteinuria at diagnosis were divided into three groups with mild (0.50-0.99 g/day; n = 264), moderate (1.00-1.99 g/day, n = 216), or severe (≥ 2.00 g/day; n = 153). Decline in kidney function and urinary remission were compared among the three groups after TSP therapy, corticosteroid (ST) therapy, or conservative therapy during a mean follow-up of 6.2 ± 3.3 years. 10.6% and 5.9% of patients in the ST and conservative therapy group underwent tonsillectomy. RESULTS The rate of urinary remission at the final observation was significantly higher in the TSP therapy group than in the ST or conservative therapy groups (mild proteinuria: 64%, 43%, and 41%; moderate proteinuria: 51%, 45%, and 28%; severe proteinuria: 48%, 30%, and 22%, respectively). In contrast, the rate of a 50% increase in serum creatinine was lower in groups TSP therapy, than ST or conservative therapy (mild proteinuria: 2.1%, 10.1% and 16.7%; moderate proteinuria: 4.8%, 8.8% and 27.7%; severe proteinuria: 12.0%, 28.9% and 43.1%, respectively). In multivariate analysis, TSP therapy significantly prevented a 50% increase in serum creatinine levels compared with conservative therapy in groups with moderate and severe proteinuria (hazard ratio, 0.12 and 0.22, respectively). CONCLUSION TSP significantly increased the rate of proteinuria disappearance and urinary remission in IgAN patients with mild-to-moderate urinary protein levels. It may also reduce the decline in kidney function in patients with moderate-to-severe urinary protein levels.
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Affiliation(s)
- Hiroyuki Komatsu
- Center for Medical Education and Career Development, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan.
| | - Shouichi Fujimoto
- Department of Medical Environment Innovation, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Yuji Sato
- Department of Internal Medicine, Division of Nephrology, National Health Insurance Takachiho Town Hospital, Takachiho, Miyazaki, Japan
| | - Takashi Yasuda
- Department of Internal Medicine, Kichijoji Asahi Hospital, Tokyo, Japan
| | - Yoshinari Yasuda
- Department of Nephrology/CKD Initiatives, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Keiichi Matsuzaki
- Department of Public Health, Kitasato University School of Medicine, Kanagawa, Japan
| | - Keita Hirano
- Division of Nephrology, Department of Internal Medicine, Japanese Red Cross Ashikaga Hospital, Ashikaga, Japan
| | - Tetsuya Kawamura
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Takashi Yokoo
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Yusuke Suzuki
- Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, Juntendo University, Tokyo, Japan
| | - Shoichi Maruyama
- Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, University of Nagoya, Nagoya, Japan
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Tunnicliffe DJ, Reid S, Craig JC, Samuels JA, Molony DA, Strippoli GF. Non-immunosuppressive treatment for IgA nephropathy. Cochrane Database Syst Rev 2024; 2:CD003962. [PMID: 38299639 PMCID: PMC10832348 DOI: 10.1002/14651858.cd003962.pub3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
BACKGROUND IgA nephropathy (IgAN) is the most common primary glomerular disease, with approximately 20% to 40% of patients progressing to kidney failure within 25 years. Non-immunosuppressive treatment has become a mainstay in the management of IgAN by improving blood pressure (BP) management, decreasing proteinuria, and avoiding the risks of long-term immunosuppressive management. Due to the slowly progressive nature of the disease, clinical trials are often underpowered, and conflicting information about management with non-immunosuppressive treatment is common. This is an update of a Cochrane review, first published in 2011. OBJECTIVES To assess the benefits and harms of non-immunosuppressive treatment for treating IgAN in adults and children. We aimed to examine all non-immunosuppressive therapies (e.g. anticoagulants, antihypertensives, dietary restriction and supplementation, tonsillectomy, and herbal medicines) in the management of IgAN. SEARCH METHODS We searched the Cochrane Kidney and Transplant Register of Studies up to December 2023 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal and ClinicalTrials.gov. SELECTION CRITERIA Randomised controlled trials (RCTs) and quasi-RCTs of non-immunosuppressive agents in adults and children with biopsy-proven IgAN were included. DATA COLLECTION AND ANALYSIS Two authors independently reviewed search results, extracted data and assessed study quality. Results were expressed as mean differences (MD) for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CI) using random-effects meta-analysis. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS This review includes 80 studies (4856 participants), of which 24 new studies (2018 participants) were included in this review update. The risk of bias within the included studies was mostly high or unclear for many of the assessed methodological domains, with poor reporting of important key clinical trial methods in most studies. Antihypertensive therapies were the most examined non-immunosuppressive therapy (37 studies, 1799 participants). Compared to placebo or no treatment, renin-angiotensin system (RAS) inhibition probably decreases proteinuria (3 studies, 199 participants: MD - 0.71 g/24 h, 95% CI -1.04 to -0.39; moderate certainty evidence) but may result in little or no difference to kidney failure or doubling of serum creatinine (SCr), or complete remission of proteinuria (low certainty evidence). Death, remission of haematuria, relapse of proteinuria or > 50% increase in SCr were not reported. Compared to symptomatic treatment, RAS inhibition (3 studies, 168 participants) probably decreases proteinuria (MD -1.16 g/24 h, 95% CI -1.52 to -0.81) and SCr (MD -9.37 µmol/L, 95% CI -71.95 to -6.80) and probably increases creatinine clearance (2 studies, 127 participants: MD 23.26 mL/min, 95% CI 10.40 to 36.12) (all moderate certainty evidence); however, the risk of kidney failure is uncertain (1 study, 34 participants: RR 0.20, 95% CI 0.01 to 3.88; very low certainty evidence). Death, remission of proteinuria or haematuria, or relapse of proteinuria were not reported. The risk of adverse events may be no different with RAS inhibition compared to either placebo or symptomatic treatment (low certainty evidence). In low certainty evidence, tonsillectomy in people with IgAN in addition to standard care may increase remission of proteinuria compared to standard care alone (2 studies, 143 participants: RR 1.90, 95% CI 1.45 to 2.47) and remission of microscopic haematuria (2 studies, 143 participants: RR 1.93, 95% CI 1.47 to 2.53) and may decrease relapse of proteinuria (1 study, 73 participants: RR 0.70, 95% CI 0.57 to 0.85) and relapse of haematuria (1 study, 72 participants: RR 0.70, 95% CI 0.51 to 0.98). Death, kidney failure and a > 50% increase in SCr were not reported. These trials have only been conducted in Japanese people with IgAN, and the findings' generalisability is unclear. Anticoagulant therapy, fish oil, and traditional Chinese medicines exhibited small benefits to kidney function in patients with IgAN when compared to placebo or no treatment. However, compared to standard care, the kidney function benefits are no longer evident. Antimalarial therapy compared to placebo in one study reported an increase in a > 50% reduction of proteinuria (53 participants: RR 3.13 g/24 h, 95% CI 1.17 to 8.36; low certainty evidence). Although, there was uncertainty regarding adverse events from this study due to very few events. AUTHORS' CONCLUSIONS Available RCTs focused on a diverse range of interventions. They were few, small, and of insufficient duration to determine potential long-term benefits on important kidney and cardiovascular outcomes and harms of treatment. Antihypertensive agents appear to be the most beneficial non-immunosuppressive intervention for IgAN. The antihypertensives examined were predominantly angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. The benefits of RAS inhibition appear to outweigh the harms in patients with IgAN. The certainty of the evidence of RCTs demonstrating a benefit of tonsillectomy to patients with Japanese patients with IgAN was low. In addition, these findings are inconsistent across observational studies in people with IgAN of other ethnicities; hence, tonsillectomy is not widely recommended, given the potential harm of therapy. The RCT evidence is insufficiently robust to demonstrate efficacy for the other non-immunosuppressive treatments evaluated here.
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Affiliation(s)
| | - Sharon Reid
- Central Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | - Jonathan C Craig
- Cochrane Kidney and Transplant, Centre for Kidney Research, The Children's Hospital at Westmead, Westmead, Australia
- College of Medicine and Public Health, Flinders University, Adelaide, Australia
| | - Joshua A Samuels
- Division of Pediatric Nephrology and Hypertension, UT-Houston Health Science Center, Houston, TX, USA
| | - Donald A Molony
- Internal Medicine, UT-Houston Health Science Center, Houston, TX, USA
| | - Giovanni Fm Strippoli
- Cochrane Kidney and Transplant, Centre for Kidney Research, The Children's Hospital at Westmead, Westmead, Australia
- Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
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Yamada K, Huang ZQ, Reily C, Green TJ, Suzuki H, Novak J, Suzuki Y. LIF/JAK2/STAT1 Signaling Enhances Production of Galactose-Deficient IgA1 by IgA1-Producing Cell Lines Derived From Tonsils of Patients With IgA Nephropathy. Kidney Int Rep 2024; 9:423-435. [PMID: 38344714 PMCID: PMC10851019 DOI: 10.1016/j.ekir.2023.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 10/13/2023] [Accepted: 11/06/2023] [Indexed: 02/28/2024] Open
Abstract
Introduction Galactose-deficient IgA1 (Gd-IgA1) plays a key role in the pathogenesis of IgA nephropathy (IgAN). Tonsillectomy has been beneficial to some patients with IgAN, possibly due to the removal of tonsillar cytokine-activated cells producing Gd-IgA1. To test this hypothesis, we used immortalized IgA1-producing cell lines derived from tonsils of patients with IgAN or obstructive sleep apnea (OSA) and assessed the effect of leukemia inhibitory factor (LIF) or oncostatin M (OSM) on Gd-IgA1 production. Methods Gd-IgA1 production was measured by lectin enzyme-linked immunosorbent assay; JAK-STAT signaling in cultured cells was assessed by immunoblotting of cell lysates; and validated by using small interfering RNA (siRNA) knock-down and small-molecule inhibitors. Results IgAN-derived cells produced more Gd-IgA1 than the cells from patients with OSA, and exhibited elevated Gd-IgA1 production in response to LIF, but not OSM. This effect was associated with dysregulated STAT1 phosphorylation, as confirmed by STAT1 siRNA knock-down. JAK2 inhibitor, AZD1480 exhibited a dose-dependent inhibition of the LIF-induced Gd-IgA1 overproduction. Unexpectedly, high concentrations of AZD1480, but only in the presence of LIF, reduced Gd-IgA1 production in the cells derived from patients with IgAN to that of the control cells from patients with OSA. Based on modeling LIF-LIFR-gp130-JAK2 receptor complex, we postulate that LIF binding to LIFR may sequester gp130 and/or JAK2 from other pathways; and when combined with JAK2 inhibition, enables full blockade of the aberrant O-glycosylation pathways in IgAN. Conclusion In summary, IgAN cells exhibit LIF-mediated overproduction of Gd-IgA1 due to abnormal signaling. JAK2 inhibitors can counter these LIF-induced effects and block Gd-IgA1 synthesis in IgAN.
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Affiliation(s)
- Koshi Yamada
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Zhi-Qiang Huang
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Colin Reily
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Todd J. Green
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Hitoshi Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Yusuke Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
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Lee M, Suzuki H, Ogiwara K, Aoki R, Kato R, Nakayama M, Fukao Y, Nihei Y, Kano T, Makita Y, Muto M, Yamada K, Suzuki Y. The nucleotide-sensing Toll-Like Receptor 9/Toll-Like Receptor 7 system is a potential therapeutic target for IgA nephropathy. Kidney Int 2023; 104:943-955. [PMID: 37648155 DOI: 10.1016/j.kint.2023.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 07/26/2023] [Accepted: 08/07/2023] [Indexed: 09/01/2023]
Abstract
The progression determinants of IgA nephropathy (IgAN) are still not fully elucidated. We have previously demonstrated that the mucosal activation of toll-like receptor (TLR) 9, which senses microbial unmethylated CpG DNA, influences progression by producing aberrantly glycosylated IgA. However, numerous recent reports of patients with IgAN presenting with gross hematuria after the mRNA vaccination for coronavirus disease 2019 suggest that the RNA-sensing system also exacerbates IgAN. Here, we investigated whether TLR7, which recognizes microbial RNA, is also involved in IgAN progression using a murine model and tonsil tissue from 53 patients with IgAN compared to samples from 40 patients with chronic tonsillitis and 12 patients with sleep apnea syndrome as controls. We nasally administered imiquimod, the ligand of TLR7, to IgAN-prone ddY mice and found that TLR7 stimulation elevated the serum levels of aberrantly glycosylated IgA and induced glomerular IgA depositions and proteinuria. Co-administered hydroxychloroquine, which inhibits TLRs, canceled the kidney injuries. In vitro, stimulating splenocytes from ddY mice with imiquimod increased interleukin-6 and aberrantly glycosylated IgA levels. The expression of TLR7 in the tonsils was elevated in patients with IgAN and positively correlated with that of a proliferation-inducing ligand (APRIL) involved in the production of aberrantly glycosylated IgA. Mechanistically, TLR7 stimulation enhanced the synthesis of aberrantly glycosylated IgA through the modulation of enzymes involved in the glycosylation of IgA. Thus, our findings suggest that nucleotide-sensing TLR9 and TLR7 play a crucial role in the pathogenesis of IgAN. Hence, nucleotide-sensing TLRs could be reasonably strong candidates for disease-specific therapeutic targets in IgAN.
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Affiliation(s)
- Mingfeng Lee
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Hitoshi Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan; Department of Nephrology, Juntendo University Urayasu Hospital, Chiba, Japan.
| | - Kei Ogiwara
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Ryosuke Aoki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Rina Kato
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Maiko Nakayama
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yusuke Fukao
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yoshihito Nihei
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Toshiki Kano
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yuko Makita
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Masahiro Muto
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Koshi Yamada
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yusuke Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan.
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Kawabe M, Yamamoto I. Current Status and Perspectives on Recurrent IgA Nephropathy after Kidney Transplantation. Nephron Clin Pract 2023; 147 Suppl 1:9-13. [PMID: 36966530 DOI: 10.1159/000530341] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 02/21/2023] [Indexed: 06/18/2023] Open
Abstract
IgA nephropathy (IgAN) is the most common form of glomerulonephritis worldwide. IgAN progresses to end-stage kidney disease in 20-40% of patients within 20 years of diagnosis. Kidney transplantation is the most effective option for patients with end-stage kidney disease caused by IgAN, but recurrence can occur in the transplanted kidney. The IgAN recurrence rate varies from 1% to 10% per year and varies according to the follow-up period, diagnostic modality, and biopsy criteria. Of note, studies based on protocol biopsies have reported a higher incidence of recurrence, which also occurred earlier after transplantation. In addition, recent data show that recurrence of IgAN is a more significant cause of allograft failure than previously believed. Little is known about the pathophysiology of IgAN recurrence, but several potential biomarkers have been investigated. Among them, galactose-deficient IgA1 (Gd-IgA1), IgG anti-Gd-IgA1 antibodies, and soluble CD89 could play a pivotal role in disease activity. This review aims to describe the current status of recurrent IgAN, including the incidence, clinical characteristics, risk factors, and future perspectives, with a focus on the available therapeutic approaches.
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Affiliation(s)
- 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
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Du Y, Cheng T, Liu C, Zhu T, Guo C, Li S, Rao X, Li J. IgA Nephropathy: Current Understanding and Perspectives on Pathogenesis and Targeted Treatment. Diagnostics (Basel) 2023; 13:diagnostics13020303. [PMID: 36673113 PMCID: PMC9857562 DOI: 10.3390/diagnostics13020303] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/06/2023] [Accepted: 01/09/2023] [Indexed: 01/19/2023] Open
Abstract
Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide, with varied clinical and histopathological features between individuals, particularly across races. As an autoimmune disease, IgAN arises from consequences of increased circulating levels of galactose-deficient IgA1 and mesangial deposition of IgA-containing immune complexes, which are recognized as key events in the widely accepted "multi-hit" pathogenesis of IgAN. The emerging evidence further provides insights into the role of genes, environment, mucosal immunity and complement system. These developments are paralleled by the increasing availability of diagnostic tools, potential biomarkers and therapeutic agents. In this review, we summarize current evidence and outline novel findings in the prognosis, clinical trials and translational research from the updated perspectives of IgAN pathogenesis.
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Mucosal Immune System Dysregulation in the Pathogenesis of IgA Nephropathy. Biomedicines 2022; 10:biomedicines10123027. [PMID: 36551783 PMCID: PMC9775168 DOI: 10.3390/biomedicines10123027] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/20/2022] [Accepted: 11/22/2022] [Indexed: 11/25/2022] Open
Abstract
The mucosal immune system, via a dynamic immune network, serves as the first line of defense against exogenous antigens. Mucosal immune system dysregulation is closely associated with the pathogenesis of immunoglobulin A nephropathy (IgAN), as illustrated by IgAN having the clinical feature of gross hematuria, often concurrent with mucosal infections. Notably, previous studies have demonstrated the efficacy of tonsillectomy and found that a targeted-release formulation of budesonide reduced proteinuria in patients with IgAN. However, it remains unclear how exogenous antigens interact with the mucosal immune system to induce or exacerbate IgAN. Thus, in this review, we focus on the dysregulation of mucosal immune response in the pathogenesis of IgAN.
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Maixnerova D, El Mehdi D, Rizk DV, Zhang H, Tesar V. New Treatment Strategies for IgA Nephropathy: Targeting Plasma Cells as the Main Source of Pathogenic Antibodies. J Clin Med 2022; 11:jcm11102810. [PMID: 35628935 PMCID: PMC9147021 DOI: 10.3390/jcm11102810] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/29/2022] [Accepted: 05/09/2022] [Indexed: 12/23/2022] Open
Abstract
Immunoglobulin A nephropathy (IgAN) is a rare autoimmune disorder and the leading cause of biopsy-reported glomerulonephritis (GN) worldwide. Disease progression is driven by the formation and deposition of immune complexes composed of galactose-deficient IgA1 (Gd-IgA1) and Gd-IgA1 autoantibodies (anti-Gd-IgA1 antibodies) in the glomeruli, where they trigger complement-mediated inflammation that can result in loss of kidney function and end-stage kidney disease (ESKD). With the risk of progression and limited treatment options, there is an unmet need for therapies that address the formation of pathogenic Gd-IgA1 antibody and anti-Gd-IgA1 antibody-containing immune complexes. New therapeutic approaches target immunological aspects of IgAN, including complement-mediated inflammation and pathogenic antibody production by inhibiting activation or promoting depletion of B cells and CD38-positive plasma cells. This article will review therapies, both approved and in development, that support the depletion of Gd-IgA1-producing cells in IgAN and have the potential to modify the course of this disease. Ultimately, we propose here a novel therapeutic approach by depleting CD38-positive plasma cells, as the source of the autoimmunity, to treat patients with IgAN.
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Affiliation(s)
- Dita Maixnerova
- Department of Nephrology, First Faculty of Medicine, General University Hospital, Charles University, 128 08 Prague, Czech Republic;
- Correspondence:
| | | | - Dana V. Rizk
- Division of Nephrology, University of Alabama at Birmingham, Birmingham, AL 35294, USA;
| | - Hong Zhang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing 100034, China;
| | - Vladimir Tesar
- Department of Nephrology, First Faculty of Medicine, General University Hospital, Charles University, 128 08 Prague, Czech Republic;
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Currie EG, Coburn B, Porfilio EA, Lam P, Rojas OL, Novak J, Yang S, Chowdhury RB, Ward LA, Wang PW, Khaleghi K, An J, Crome SQ, Hladunewich MA, Barbour SJ, Cattran DC, Parekh RS, Licht C, John R, Kaul R, Croitoru K, Gray-Owen SD, Guttman DS, Gommerman JL, Reich HN. Immunoglobulin A nephropathy is characterized by anti-commensal humoral immune responses. JCI Insight 2022; 7:141289. [PMID: 35133979 PMCID: PMC8983137 DOI: 10.1172/jci.insight.141289] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 02/02/2022] [Indexed: 11/17/2022] Open
Abstract
IgA nephropathy (IgAN) is a leading cause of kidney failure, yet little is known about the immunopathogenesis of this disease. IgAN is characterized by deposition of IgA in the kidney glomeruli, but the source and stimulus for IgA production are not known. Clinical and experimental data suggest a role for aberrant immune responses to mucosal microbiota in IgAN, and in some countries with high disease prevalence, tonsillectomy is regarded as standard-of-care therapy. To evaluate the relationship between microbiota and mucosal immune responses, we characterized the tonsil microbiota in patients with IgAN versus nonrelated household-matched control group participants and identified increased carriage of the genus Neisseria and elevated Neisseria-targeted serum IgA in IgAN patients. We reverse-translated these findings in experimental IgAN driven by BAFF overexpression in BAFF-transgenic mice rendered susceptible to Neisseria infection by introduction of a humanized CEACAM-1 transgene (B × hC-Tg). Colonization of B × hC-Tg mice with Neisseria yielded augmented levels of systemic Neisseria-specific IgA. Using a custom ELISPOT assay, we discovered anti-Neisseria–specific IgA-secreting cells within the kidneys of these mice. These findings suggest a role for cytokine-driven aberrant mucosal immune responses to oropharyngeal pathobionts, such as Neisseria, in the immunopathogenesis of IgAN. Furthermore, in the presence of excess BAFF, pathobiont-specific IgA can be produced in situ within the kidney.
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Affiliation(s)
- Elissa G Currie
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Bryan Coburn
- Department of Medicine, University of Toronto, Toronto, Canada
| | - Elisa A Porfilio
- Department of Immunology, University of Toronto, Toronto, Canada
| | - Ping Lam
- Division of Nephrology, Toronto General Research Institute, Toronto, Canada
| | - Olga L Rojas
- Department of Immunology, University of Toronto, Toronto, Canada
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, United States of America
| | - Stuart Yang
- Division of Nephrology, Toronto General Research Institute, Toronto, Canada
| | - Raad B Chowdhury
- Division of Nephrology, Toronto General Research Institute, Toronto, Canada
| | - Lesley A Ward
- Department of Immunology, University of Toronto, Toronto, Canada
| | - Pauline W Wang
- Department of Cell & Systems Biology, University of Toronto, Toronto, Canada
| | | | - James An
- Division of Nephrology, Toronto General Research Institute, Toronto, Canada
| | - Sarah Q Crome
- Division of Nephrology, Toronto General Research Institute, Toronto, Canada
| | | | - Sean J Barbour
- Department of Medicine, University of British Columbia, Vancouver, Canada
| | - Daniel C Cattran
- Division of Nephrology, University Health Network, Toronto, Canada
| | - Rulan S Parekh
- Department of Medicine, The Hospital for Sick Children, Toronto, Canada
| | - Christoph Licht
- Department of Medicine, The Hospital for Sick Children, Toronto, Canada
| | - Rohan John
- Department of Laboratory Medicine and Pathology, University of Toronto, Toronto, Canada
| | - Rupert Kaul
- Department of Medicine, University of Toronto, Toronto, Canada
| | - Kenneth Croitoru
- Division of Gastroenterology, Mount Sinai Hospital, Toronto, Canada
| | - Scott D Gray-Owen
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - David S Guttman
- Department of Cell & Systems Biology, University of Toronto, Toronto, Canada
| | | | - Heather N Reich
- Division of Nephrology, University Health Network, Toronto, Canada
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Nagasawa Y, Misaki T, Ito S, Naka S, Wato K, Nomura R, Matsumoto-Nakano M, Nakano K. Title IgA Nephropathy and Oral Bacterial Species Related to Dental Caries and Periodontitis. Int J Mol Sci 2022; 23:725. [PMID: 35054910 PMCID: PMC8775524 DOI: 10.3390/ijms23020725] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/04/2022] [Accepted: 01/07/2022] [Indexed: 12/23/2022] Open
Abstract
A relationship between IgA nephropathy (IgAN) and bacterial infection has been suspected. As IgAN is a chronic disease, bacteria that could cause chronic infection in oral areas might be pathogenetic bacteria candidates. Oral bacterial species related to dental caries and periodontitis should be candidates because these bacteria are well known to be pathogenic in chronic dental disease. Recently, several reports have indicated that collagen-binding protein (cnm)-(+) Streptococcs mutans is relate to the incidence of IgAN and the progression of IgAN. Among periodontal bacteria, Treponema denticola, Porphyromonas gingivalis and Campylobacte rectus were found to be related to the incidence of IgAN. These bacteria can cause IgAN-like histological findings in animal models. While the connection between oral bacterial infection, such as infection with S. mutans and periodontal bacteria, and the incidence of IgAN remains unclear, these bacterial infections might cause aberrantly glycosylated IgA1 in nasopharynx-associated lymphoid tissue, which has been reported to cause IgA deposition in mesangial areas in glomeruli, probably through the alteration of microRNAs related to the expression of glycosylation enzymes. The roles of other factors related to the incidence and progression of IgA, such as genes and cigarette smoking, can also be explained from the perspective of the relationship between these factors and oral bacteria. This review summarizes the relationship between IgAN and oral bacteria, such as cnm-(+) S. mutans and periodontal bacteria.
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Affiliation(s)
- Yasuyuki Nagasawa
- Department of General Internal Medicine, Hyogo College of Medicine, Nishinomiya 663-8501, Hyogo, Japan
| | - Taro Misaki
- Division of Nephrology, Seirei Hamamatsu General Hospital, Hamamatsu 430-8558, Shizuoka, Japan;
- Department of Nursing, Faculty of Nursing, Seirei Christopher University, Hamamatsu 433-8558, Shizuoka, Japan
| | - Seigo Ito
- Department of Internal Medicine, Japan Self-Defense Gifu Hospital, Kakamigahara 502-0817, Gifu, Japan;
| | - Shuhei Naka
- Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8525, Okayama, Japan; (S.N.); (M.M.-N.)
| | - Kaoruko Wato
- Department of Pediatric Dentistry, Division of Oral Infection and Disease Control, Osaka University Graduate School of Dentistry, Suita 565-0871, Osaka, Japan; (K.W.); (R.N.); (K.N.)
| | - Ryota Nomura
- Department of Pediatric Dentistry, Division of Oral Infection and Disease Control, Osaka University Graduate School of Dentistry, Suita 565-0871, Osaka, Japan; (K.W.); (R.N.); (K.N.)
| | - Michiyo Matsumoto-Nakano
- Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8525, Okayama, Japan; (S.N.); (M.M.-N.)
| | - Kazuhiko Nakano
- Department of Pediatric Dentistry, Division of Oral Infection and Disease Control, Osaka University Graduate School of Dentistry, Suita 565-0871, Osaka, Japan; (K.W.); (R.N.); (K.N.)
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11
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Haniuda K, Gommerman JL, Reich HN. The microbiome and IgA nephropathy. Semin Immunopathol 2021; 43:649-656. [PMID: 34664087 DOI: 10.1007/s00281-021-00893-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 09/16/2021] [Indexed: 12/12/2022]
Abstract
The immunopathogenic mechanisms underlying immunoglobulin A nephropathy (IgAN) are poorly understood, yet it is one of the most common causes of kidney failure globally. The commonly referenced syndrome of synpharyngitic gross hematuria as a presenting feature of IgAN has led to a logical association between infections and development of IgAN, however no pathogenic organism has been clearly linked to IgAN. Advances in sequencing technology have enabled more detailed characterization of host microbial communities, and highlighted the interrelationship between microbiota and immune responses in health and disease. This review will summarize current thinking on the relationship between microbiota and development of IgAN with a focus on recent studies relating aberrant mucosal IgA-biased immune responses to microbiota and how this may be related to the immunopathogenesis of IgAN.
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Affiliation(s)
- Kei Haniuda
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| | | | - Heather N Reich
- Division of Nephrology, Department of Medicine, University of Toronto and University Health Network, Toronto, ON, Canada.
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12
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Pathogenesis of IgA Nephropathy: Current Understanding and Implications for Development of Disease-Specific Treatment. J Clin Med 2021; 10:jcm10194501. [PMID: 34640530 PMCID: PMC8509647 DOI: 10.3390/jcm10194501] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 09/22/2021] [Indexed: 12/20/2022] Open
Abstract
IgA nephropathy, initially described in 1968 as a kidney disease with glomerular “intercapillary deposits of IgA-IgG”, has no disease-specific treatment and is a common cause of kidney failure. Clinical observations and laboratory analyses suggest that IgA nephropathy is an autoimmune disease wherein the kidneys are damaged as innocent bystanders due to deposition of IgA1-IgG immune complexes from the circulation. A multi-hit hypothesis for the pathogenesis of IgA nephropathy describes four sequential steps in disease development. Specifically, patients with IgA nephropathy have elevated circulating levels of IgA1 with some O-glycans deficient in galactose (galactose-deficient IgA1) and these IgA1 glycoforms are recognized as autoantigens by unique IgG autoantibodies, resulting in formation of circulating immune complexes, some of which deposit in glomeruli and activate mesangial cells to induce kidney injury. This proposed mechanism is supported by observations that (i) glomerular immunodeposits in patients with IgA nephropathy are enriched for galactose-deficient IgA1 glycoforms and the corresponding IgG autoantibodies; (ii) circulatory levels of galactose-deficient IgA1 and IgG autoantibodies predict disease progression; and (iii) pathogenic potential of galactose-deficient IgA1 and IgG autoantibodies was demonstrated in vivo. Thus, a better understanding of the structure–function of these immunoglobulins as autoantibodies and autoantigens will enable development of disease-specific treatments.
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13
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Suzuki H, Novak J. IgA glycosylation and immune complex formation in IgAN. Semin Immunopathol 2021; 43:669-678. [PMID: 34570260 DOI: 10.1007/s00281-021-00883-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 07/24/2021] [Indexed: 12/17/2022]
Abstract
IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. This disease, discovered in 1968, is characterized by IgA-IgG glomerular immunodeposits with a mesangial pattern. It is thought that these immunodeposits originate from the immune complexes formed in the circulation. It is hypothesized that the pathogenesis of IgAN is driven by aberrant glycoforms of IgA1 (galactose-deficient IgA1, Gd-IgA1). Gd-IgA1, in genetically susceptible individuals, represents the initiating factor for the formation of circulating immune complexes due to its recognition by IgG autoantibodies and the subsequent formation of pathogenic IgA1-IgG immune complexes. Complement activation through alternative and/or lectin pathways is likely playing an important role in the pathogenic properties of these complexes and may further upregulate local inflammatory responses and glomerular injury.
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Affiliation(s)
- Hitoshi Suzuki
- Department of Nephrology, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Chiba, 279-0021, Japan.
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, 845 19th Street South, BBRB 761A, AL, 35294, Birmingham, USA.
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14
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Are there animal models of IgA nephropathy? Semin Immunopathol 2021; 43:639-648. [PMID: 34230994 DOI: 10.1007/s00281-021-00878-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 06/08/2021] [Indexed: 12/18/2022]
Abstract
Immunoglobulin A (IgA) nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. Up to 40% of IgAN patients develop end-stage kidney disease after 15-20 years. Despite the poor prognosis associated with this multifactorial disease, no clear treatment strategy has been identified, primarily due to the lack of understanding of its pathogenesis. Clinical observations indicate that aberrant IgAN immune systems, rather than intrinsic renal abnormalities, may be involved in its pathogenesis. Moreover, nephritogenic IgA and its related immune complexes are considered to be produced not only in the mucosa, but also in systemic immune sites, such as the bone marrow; however, there are numerous challenges to understanding this dynamic and complex immune axis in humans. Thus, several investigators have used experimental animal models. Although there are inter-strain differences in IgA molecules and immune responses between humans and rodents, animal models remain a powerful tool for investigating IgAN's pathogenesis, and the subsequent development of effective treatments. Here, we introduced some classical models of IgAN with or without genetic manipulation and recent translational approaches with some promising models. This includes humanized mouse models expressing human IgA1 and human IgA Fc receptor (CD89) that develops spontaneously the disease. Pre-clinical studies targeting IgA1 are discussed. Together, animal models are very useful tools to study pathophysiology and to validate new therapeutic approaches for IgAN.
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15
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Suzuki Y, Monteiro RC, Coppo R, Suzuki H. The Phenotypic Difference of IgA Nephropathy and its Race/Gender-dependent Molecular Mechanisms. KIDNEY360 2021; 2:1339-1348. [PMID: 35369654 PMCID: PMC8676395 DOI: 10.34067/kid.0002972021] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 05/24/2021] [Indexed: 02/08/2023]
Abstract
IgA nephropathy (IgAn), defined by the pre dominant de position of IgA in the glomerular mesangium, is the most common form of GN throughout the world. However, its incidence, sex distribution, clinical presentation, and progression and pathogenic initiating factors are largely variable and do not fit such a simple definition. To assess the heterogeneity of this disease, we recently conducted a clinical survey on the presentation and clinical management of patients with IgAn in Europe and Japan. This clinical survey highlights similarities and differences in patients from different cont inents. The survey revealed obvious differences between nations in the frequency of gastrointestinal complications, including inflammatory bowel diseases (IBD) and celiac disease, which were more frequent in European patients. Such findings are compatible with susceptibility loci related to intestinal immunity and IBD in recent genome wide association studies (GWAS) on IgAn. However, most of the molecules in these mucosal-related loci fulfill the immunologic function not only of gut-associated lymphoid tissue (GALT), but also nasopharyngeal/bronchial-associated lymphoid tissues (NALT/BALT). Indeed, a similar frequency of macrohematuria coinciding with upper respiratory infection, a hallmark manifestation of this disease, was found in the survey, emphasizing the pathogenic roles of these molecules in the NALT/BALT of patients with IgAn. Recent experimental and clinical studies including GWAS on multiple common infections and IBD indicate immune crosstalk between GALT and NALT/BALT, and some related mediators, such as TNF superfamily ligands (APRIL/BAFF). This review explains the epidemiologic heterogeneity of this disease with the clinical survey, and discusses race and sex-dependent molecular mechanisms.
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Affiliation(s)
- Yusuke Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Renato C. Monteiro
- Faculty of Medicine, University of Paris, Paris, France,Center for Research on Inflammation, Paris, France,Inflamex Laboratory of Excellence, Paris, France,Immunology Department, Bichat Hospital, Assistance Publique de Paris, Paris, France
| | | | - Hitoshi Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
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16
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Nagai M, Kobayashi N, Izumi N, Ohbayashi T, Hotta O, Hamano T. Pre-treatment hematuria and crescents predict estimated glomerular filtration rate trajectory after methylprednisolone pulse therapy with tonsillectomy for IgA nephropathy. J Nephrol 2021; 35:441-449. [PMID: 34014510 DOI: 10.1007/s40620-021-01064-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 05/09/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Glomerular hematuria and proteinuria are typical manifestations of IgA nephropathy (IgAN). However, hematuria severity is not considered a useful marker of the potential benefits of corticosteroid administration as proteinuria severity only is included in the current guidelines. METHODS In this retrospective cohort study, we enrolled 133 patients diagnosed with IgAN through biopsy. We calculated the 2-year estimated glomerular filtration rate (eGFR) slope (mL/min/1.73m2/year) and eGFR trajectory after methylprednisolone pulse therapy using mixed effects models stratified by the Oxford classification and three categories of pre-treatment hematuria: mild [urinary red blood cells (URBCs) < 10/high-power field (HPF)], moderate (URBCs 10-30/HPF), and severe (URBCs ≥ 30/HPF). RESULTS The severe pre-treatment hematuria group showed a significantly higher likelihood of having crescents (odds ratio (OR), 4.3; 95% confidence interval (CI), 1.7-10.9). In the longitudinal analysis of 103 patients, most of whom underwent tonsillectomy, the severe pre-treatment hematuria group had a significantly higher 2-year eGFR slope after methylprednisolone pulse therapy than the mild and moderate hematuria groups (mild, -0.52 ± 1.97; moderate, -0.32 ± 1.99; severe, 1.44 ± 3.20 mL/min/1.73m2/year). Patients with C2 scores showed a significantly higher 2-year eGFR slope after methylprednisolone pulse therapy than those with C0 and C1 scores (C0, -0.38 ± 1.74; C1, 0.81 ± 3.02; C2, 3.29 ± 3.68 mL/min/1.73m2/year). Analyses of eGFR trajectory after methylprednisolone pulse therapy revealed that the eGFR improved only in patients with severe pre-treatment hematuria or C2 score (Pinteraction with time < 0.001). CONCLUSIONS The eGFR is likely to improve after methylprednisolone pulse therapy with tonsillectomy in IgAN patients with severe pre-treatment hematuria or a high percentage of crescents.
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Affiliation(s)
- Masaaki Nagai
- Department of Nephrology, Nagoya City University Graduate School of Medical Sciences, 1, Azakawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8602, Japan.,Division of Nephrology, Narita Memorial Hospital, Toyohashi, Aichi, Japan
| | - Naoto Kobayashi
- Division of Nephrology, Narita Memorial Hospital, Toyohashi, Aichi, Japan
| | - Naoki Izumi
- Division of Nephrology, Narita Memorial Hospital, Toyohashi, Aichi, Japan
| | - Takaaki Ohbayashi
- Division of Nephrology, Narita Memorial Hospital, Toyohashi, Aichi, Japan
| | - Osamu Hotta
- Division of Nephrology, Narita Memorial Hospital, Toyohashi, Aichi, Japan.,Hotta Osamu Clinic, Sendai, Miyagi, Japan
| | - Takayuki Hamano
- Department of Nephrology, Nagoya City University Graduate School of Medical Sciences, 1, Azakawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8602, Japan.
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17
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Kano T, Suzuki H, Makita Y, Fukao Y, Suzuki Y. Nasal-associated lymphoid tissue is the major induction site for nephritogenic IgA in murine IgA nephropathy. Kidney Int 2021; 100:364-376. [PMID: 33961870 DOI: 10.1016/j.kint.2021.04.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 03/31/2021] [Accepted: 04/08/2021] [Indexed: 12/15/2022]
Abstract
Dysregulation of mucosal immunity may play a role in the pathogenesis of IgA nephropathy (IgAN). However, it is unclear whether the nasal-associated lymphoid tissue (NALT) or gut-associated lymphatic tissue is the major induction site of nephritogenic IgA synthesis. To examine whether exogenous mucosal antigens exacerbate the pathogenesis of IgAN, we assessed the disease phenotypes of IgAN-onset ddY mice housed germ-free. These mice were transferred to a specific pathogen-free environment and divided into three groups: challenged with the Toll-like receptor 9 (TLR9) ligand CpG-oligodeoxynucleotide, fecal transplantation, and the untreated control group. The levels of aberrantly glycosylated IgA and IgG-IgA immune complexes were measured in the serum and supernatant of cultured cells purified from the NALT, mesenteric lymph nodes, and Peyer's patch. Although the germ-free IgAN-onset ddY mice did not develop IgAN, they showed aggravation of kidney injury with mesangial IgA deposition after transfer to the specific pathogen-free state. The NALT cells produced more aberrantly glycosylated IgA than those from the mesenteric lymph node and Peyer's patch, resulting in induction of IgG-IgA immune complexes formation. Additionally, TLR9 enhanced the production of nephritogenic IgA and IgG-IgA immune complexes by nasal-associated lymphoid but not gut-associated lymphatic cells. Furthermore, the germ-free IgAN-onset ddY mice nasally immunized with CpG-oligonucleotide showed aggravation of kidney injury with mesangial IgA deposition, whereas those that received fecal transplants did not develop IgAN. Thus, NALT is the major induction site of the production of aberrantly glycosylated IgA in murine IgAN.
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Affiliation(s)
- Toshiki Kano
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Hitoshi Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan.
| | - Yuko Makita
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yusuke Fukao
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yusuke Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan.
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18
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Medrano AS, Muijsemberg A, Wimbury D, Martin M, Jatem E, González J, Colás-Campás L, García-Carrasco A, Martínez C, Barratt J. Relationship between IgA1 lectin-binding specificities, mesangial C4d deposits and clinical phenotypes in IgA nephropathy. Nephrol Dial Transplant 2020; 37:318-325. [PMID: 33315098 DOI: 10.1093/ndt/gfaa356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND AND OBJECTIVES The reason why mesangial C4d deposits are detected in only certain biopsies of IgA nephropathy remains unclear. We analyse the association between IgA glycosylation patterns, mesangial C4 deposition and clinical phenotypes in IgA nephropathy.Design, setting, participants and measurements: This cross-sectional study included 145 patients with idiopathic IgA nephropathy. We measured the serum levels of three different IgA1 lectin-binding specificities, using enzyme-linked-immunosorbent assays with and without treatment with neuraminidase, and we analysed the relationship between these glycoforms, C4d mesangial deposits and clinical phenotypes. RESULTS C4d-positive vs Cd4-negative patients had higher proteinuria (median: 3.1 g/g [0.9-4.2] vs. 1.8 g/g [1-2.2]; p = 0.000), hematuria (223 cel/µL [32-278] vs 99 cel/µL [25-186], p = 0.000), and higher levels of IgA binding to neuraminidase untreated Helix Aspersa (HA IgA1 neu-) (150.6 ± 52 U vs 96.2 ± 64.1 U, p = 0.000), neuraminidase untreated Helix Pomatia (HPA IgA1 neu-) (0.34 ± 0.15 vs 0.27 ± 0.13p = 0.04), Triticum vulgaris (TV IgA1) (85.1 ± 31.7 vs42.2 ± 26.9p = 0.000), and Canavalia ensiformis (ConA IgA1) (32.5 ± 18 U vs 16.7 ± 9.38 U, p = 0.000). The levels of HA IgA1 neu-, HPA IgA1 neu-, TV IgA1 and ConA IgA1 were all associated with the mesangial deposition of C4d, extracapillary proliferation and acute kidney injury. In ROC curves, HA IgA1 neu-, HPA IgA1 neu-, TV IgA1 and ConA IgA1 significantly discriminated between C4d positive ad C4d-negative biopsies. In logistic models, TVIgA1 and ConAIgA1 were the only independent predictors of mesangial C4d deposits. CONCLUSIONS In IgA nephropathy, the severity of the disease is associated with the level of IgA exposing N-Acetyl-D-Galactosamine, N-Acetyl-D-Glucosamine or mannose whereas C4d deposits are only associated with elevated levels of IgA1 glycoforms exhibiting glycan residues with specificity for mannose and N-Acetyl-D-Glucosamine binding lectins.
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Affiliation(s)
- Alfons Segarra Medrano
- Servicio de Nefrología. Hospital Arnau de Vilanova, Lleida, Spain.,Institut de Recerca Biomèdica, Lleida, Spain
| | - Andrea Muijsemberg
- Servicio de Nefrología. Hospital Arnau de Vilanova, Lleida, Spain.,Institut de Recerca Biomèdica, Lleida, Spain.,Universitat Autònoma de Barcelona, Spain
| | - David Wimbury
- The Mayer IgA Nephropathy Laboratories, University of Leicester, UK
| | - Marisa Martin
- Servicio de Nefrología. Hospital Arnau de Vilanova, Lleida, Spain.,Institut de Recerca Biomèdica, Lleida, Spain
| | - Elias Jatem
- Servicio de Nefrología. Hospital Arnau de Vilanova, Lleida, Spain.,Institut de Recerca Biomèdica, Lleida, Spain
| | - Jorge González
- Servicio de Nefrología. Hospital Arnau de Vilanova, Lleida, Spain.,Institut de Recerca Biomèdica, Lleida, Spain
| | - Laura Colás-Campás
- Grupo de Neurociencias Clínicas, Institut de Recerca Biomèdica de Lleida (IRBLleida). Universitat de Lleida (UdL), Lleida, Spain
| | - Alicia García-Carrasco
- Vascular and Renal Translational Research Group, Institut de Recerca Biomèdica de Lleida (IRBLleida). Universitat de Lleida (UdL), Lleida, Spain
| | - Cristina Martínez
- Servicio de Nefrología. Hospital Arnau de Vilanova, Lleida, Spain.,Institut de Recerca Biomèdica, Lleida, Spain.,Vascular and Renal Translational Research Group, Institut de Recerca Biomèdica de Lleida (IRBLleida). Universitat de Lleida (UdL), Lleida, Spain
| | - Jonathan Barratt
- The Mayer IgA Nephropathy Laboratories, University of Leicester, UK
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19
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Moriyama T, Karasawa K, Miyabe Y, Akiyama K, Iwabuchi Y, Ogura S, Takabe T, Sugiura N, Seki M, Hanafusa N, Uchida K, Nitta K. Long-Term Beneficial Effects of Tonsillectomy on Patients with Immunoglobulin A Nephropathy. KIDNEY360 2020; 1:1270-1283. [PMID: 35372877 PMCID: PMC8815505 DOI: 10.34067/kid.0003932020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 09/01/2020] [Indexed: 06/14/2023]
Abstract
BACKGROUND Tonsillectomy may treat IgA nephropathy (IgAN) by reducing the levels of galactose-deficient IgA1. Therefore, we aimed to analyze the long-term effects of tonsillectomy on patients with IgAN, as an initial treatment and as a treatment at any time in their lives. METHODS In this retrospective cohort analysis, 1147 patients with IgAN were grouped according to whether they had undergone tonsillectomy at any time, >1 year after renal biopsy (study 1), or within 1 year after renal biopsy (study 2). The patients were propensity-score matched or divided into four groups according to their proteinuria and renal function. The 20-year renal survival rates were evaluated until serum creatinine levels doubled (primary end point) and ESKD occurred (secondary end point). RESULTS Patients in both studies had similar background characteristics after propensity score matching. In study 1, the renal survival rates for the primary and secondary end points were significantly higher for patients who underwent tonsillectomy at any time or >1 year after renal biopsy compared with those who did not. In study 2, the renal survival rates for the primary and secondary end points were significantly higher for patients who underwent tonsillectomy soon after renal biopsy compared with those who did not (primary end point, 98% versus 69%, P=0.001; secondary end point, 100% versus 75%, P=0.0001). A stratified analysis showed that significant treatment efficacy was observed for patients with proteinuria >1.0 g/d. Multivariate Cox regression analyses showed that tonsillectomy was associated with disease progression (hazard ratio, 0.27; P=0.04). Complications associated with tonsillectomy occurred in 8% of patients. CONCLUSIONS Among patients with IgAN, tonsillectomy at any time of life, or soon after renal biopsy, prevents disease progression, and the procedure is relatively safe.
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Affiliation(s)
- Takahito Moriyama
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Kazunori Karasawa
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Yoei Miyabe
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Kenichi Akiyama
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Yuko Iwabuchi
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Shota Ogura
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Tomo Takabe
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Naoko Sugiura
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Momoko Seki
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Norio Hanafusa
- Department of Blood Purification, Tokyo Women’s Medical University, Tokyo, Japan
| | - Keiko Uchida
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
| | - Kosaku Nitta
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo, Japan
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20
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Nishino Y, Enya T, Miyazaki K, Morimoto Y, Marutani S, Okada M, Sugimoto K. The potentially therapeutic role of tonsillectomy in the alleviation of several renal diseases apart from IgA nephropathy. Med Hypotheses 2020; 146:110405. [PMID: 33261919 DOI: 10.1016/j.mehy.2020.110405] [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: 06/09/2020] [Revised: 11/15/2020] [Accepted: 11/17/2020] [Indexed: 11/26/2022]
Abstract
Tonsils are located mainly at the gateway of the respiratory tract, and are reportedly one of the secondary lymphatic organs of the immune system. The development of several diseases including IgA nephropathy (IgAN) is associated with inflammatory stimulation and an aberrant immune response of the tonsils. Several studies have reported an improvement in and/or an increase in the stability of the clinicopathological findings of patients with IgAN post tonsillectomy. However, the efficacy in and precise mechanism of the alleviation of symptoms of other renal diseases by tonsillectomy remain unknown. We hypothesize that tonsillectomy may play a potentially therapeutic role in renal diseases apart from IgAN, which are thought to be caused by an impaired regulation of the immune system.
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Affiliation(s)
- Yuuki Nishino
- Department of Pediatrics, Kindai University, Faculty of Medicine, Osaka, Japan
| | - Takuji Enya
- Department of Pediatrics, Kindai University, Faculty of Medicine, Osaka, Japan
| | - Kohei Miyazaki
- Department of Pediatrics, Kindai University, Faculty of Medicine, Osaka, Japan
| | - Yuichi Morimoto
- Department of Pediatrics, Kindai University, Faculty of Medicine, Osaka, Japan
| | - Satoshi Marutani
- Department of Pediatrics, Kindai University, Faculty of Medicine, Osaka, Japan
| | - Mitsuru Okada
- Department of Pediatrics, Kindai University, Faculty of Medicine, Osaka, Japan
| | - Keisuke Sugimoto
- Department of Pediatrics, Kindai University, Faculty of Medicine, Osaka, Japan.
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21
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Selvaskandan H, Shi S, Twaij S, Cheung CK, Barratt J. Monitoring Immune Responses in IgA Nephropathy: Biomarkers to Guide Management. Front Immunol 2020; 11:572754. [PMID: 33123151 PMCID: PMC7572847 DOI: 10.3389/fimmu.2020.572754] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/17/2020] [Indexed: 11/13/2022] Open
Abstract
IgA nephropathy (IgAN) is the commonest biopsy-reported primary glomerulonephritis worldwide. It has an incidence which peaks among young adults, and 30 to 40% of patients' progress to end stage kidney disease within twenty years of diagnosis. Ten-year kidney survival rates have been reported to be as low as 35% in some parts of the world. The successful management of IgAN is limited by an incomplete understanding of the pathophysiology of IgAN and a poor understanding of how pathophysiology may vary both from patient to patient and between patient groups, particularly across races. This is compounded by a lack of rigorously designed and delivered clinical trials in IgAN. This is slowly changing, with a number of Phase 2 and 3 clinical trials of novel therapies targeting a number of different putative pathogenic pathways in IgAN due to report in the next 5 years. From our current, albeit limited, understanding of the pathophysiology of IgAN it is unlikely a single therapy will be effective in all patients with IgAN. The successful management of IgAN in the future is, therefore, likely to be reliant on targeted therapies, carefully selected based on an individualized understanding of a patient's risk of progression and underlying pathophysiology. The potential role of biomarkers to facilitate personalization of prognostication and treatment of IgAN is immense. Here we review the progress made over the past decade in identifying and validating new biomarkers, with a particular focus on those that reflect immunological responses in IgAN.
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Affiliation(s)
- Haresh Selvaskandan
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Sufang Shi
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Sara Twaij
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Chee Kay Cheung
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Jonathan Barratt
- Mayer IgA Nephropathy Laboratories, Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
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22
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Umeda C, Fujinaga S, Endo A, Sakuraya K, Asanuma S, Hirano D. Preventive Effect of Tonsillectomy on Recurrence of Henoch-Schönlein Purpura Nephritis after Intravenous Methylprednisolone Pulse Therapy. TOHOKU J EXP MED 2020; 250:61-69. [PMID: 31996498 DOI: 10.1620/tjem.250.61] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Henoch-Schönlein purpura (HSP) is regarded as a benign and self-limiting vasculitis characterized by purpura, arthritis, and gastrointestinal symptoms; however, about one third of the patients develop HSP nephritis (HSPN), the most serious long-term complication. Since 2013, we have proposed that tonsillectomy in addition to intravenous methylprednisolone pulse therapy (IVMP) be performed in all patients with HSPN, similar to immunoglobulin A nephropathy (IgAN) patients because both diseases are considered to a share common pathogenesis. Herein, we retrospectively reviewed the clinical courses of 71 Japanese children with HSPN (34 boys; median age at diagnosis, 6.7 years; median follow-up period, 5.6 years) who had received initial treatment with IVMP (15-20 mg/kg; on 3 consecutive days/week for 3 weeks) followed by oral prednisolone (initially 1 mg/kg; tapered off within 12 months) and achieved clinical remission (i.e., disappearance of both proteinuria and hematuria). The patients were divided into two groups: 31 patients receiving tonsillectomy after IVMP between 2013 and 2017 (tonsillectomy group) and 40 patients receiving IVMP monotherapy between 2003 and 2012 (IVMP group). For the 2 years after IVMP therapy, the rate of HSPN recurrence (i.e., persistent proteinuria combined with hematuria requiring additional treatments) after clinical remission was significantly lower in the tonsillectomy group than the IVMP group (0% vs. 19%, P < 0.05). Despite the short follow-up period in the tonsillectomy group, this study provides the evidence that tonsillectomy may be beneficial for preventing recurrence of HSPN from clinical remission with IVMP therapy in Japanese children.
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Affiliation(s)
- Chisato Umeda
- Division of Nephrology, Saitama Children's Medical Center.,Department of Pediatrics, The Jikei University School of Medicine
| | | | - Amane Endo
- Department of Pediatrics and Adolescent Medicine, Juntendo University School of Medicine
| | - Koji Sakuraya
- Division of Nephrology, Saitama Children's Medical Center.,Department of Pediatrics and Adolescent Medicine, Juntendo University School of Medicine
| | - Satoshi Asanuma
- Division of Otorhinolaryngology, Saitama Children's Medical Center
| | - Daishi Hirano
- Department of Pediatrics, The Jikei University School of Medicine
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23
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He JW, Zhou XJ, Lv JC, Zhang H. Perspectives on how mucosal immune responses, infections and gut microbiome shape IgA nephropathy and future therapies. Am J Cancer Res 2020; 10:11462-11478. [PMID: 33052226 PMCID: PMC7545987 DOI: 10.7150/thno.49778] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 08/30/2020] [Indexed: 02/06/2023] Open
Abstract
Infections have been considered to play a critical role in the pathogenesis of IgA nephropathy (IgAN) because synpharyngitic hematuria is a common feature in IgAN. However, how infections participate in this process is still debated. More recent studies have also revealed that the alteration of the gut microbiome exerts a profound effect on host immune responses, contributing to the etiology or progression of autoimmunity. Considering IgA as the first line of defense against bacterial and viral antigens, this review evaluates the relationships among intestinal infections, gut microbiome, and IgA for a better understanding of the pathogenesis of IgAN. Moreover, as a prototype of IgA immunity, we provide detailed clarification of IgAN pathogenesis to shed light on other diseases in which IgA plays a role. Finally, we discuss potential therapies focusing on microbes and mucosal immune responses in IgAN.
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24
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Impact of the number of steroid pulses in tonsillectomy combined with steroid pulse therapy: a nationwide retrospective study in Japan. Clin Exp Nephrol 2020; 25:19-27. [PMID: 32880761 DOI: 10.1007/s10157-020-01960-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/21/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Steroid pulse therapy with tonsillectomy is known as a major treatment for IgA nephropathy (IgAN). However, its protocol was different among institutions and the effects of varying the number of steroid pulses remain unclear. METHODS From a total of 1,174 IgAN patients in a multicenter retrospective cohort analysis in Japan, 195 patients were treated by tonsillectomy combined with corticosteroid. They were divided into four groups based on the number of administered steroid pulses from 0 to three (TSP0-3), and remission of urinary abnormalities and renal survival until 1.5-fold increase in serum creatinine level from baseline were analyzed among the four groups and between TSP1 and TSP3. RESULTS Among the four groups, renal function was relatively good when the estimated glomerular filtration rate was approximately 80-90 mL/min/1.73m2 and proteinuria was relatively mild (< 1.0 g/gCre). The ratio of patients who developed renal dysfunction was < 5% in all groups, and the cumulative renal survival rate by Kaplan-Meier analysis was similar among groups (log-rank test, p = 0.37), despite varying clinical backgrounds and treatments. After adjustment of the background variables between TSP1 and TSP3, the remission rates of urinary abnormalities were similar and the renal survival rate also remained similar (66.8 vs. 85.4%, p = 0.45). CONCLUSIONS In patients with mild proteinuria and good renal function, the number of steroid pulses did not affect the renal outcome in steroid pulse therapy with tonsillectomy. The adaptation and protocols, such as the number of steroid pulses, should be determined for each IgAN patient's background.
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25
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Zheng N, Xie K, Ye H, Dong Y, Wang B, Luo N, Fan J, Tan J, Chen W, Yu X. TLR7 in B cells promotes renal inflammation and Gd-IgA1 synthesis in IgA nephropathy. JCI Insight 2020; 5:136965. [PMID: 32699192 PMCID: PMC7453916 DOI: 10.1172/jci.insight.136965] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 06/10/2020] [Indexed: 12/14/2022] Open
Abstract
TLR7 has been linked to the pathogenesis of glomerulonephritis, but its precise roles are not clear. In this study, we evaluated the roles of TLR7 in IgA nephropathy (IgAN). TLR7 proteins were abundant in CD19+ B cells infiltrated in the kidneys of patients with IgAN. The intensities of both intrarenal TLR7 and CD19 proteins were closely associated with kidney function (estimated glomerular filtration rate [eGFR] and serum creatinine concentration) and renal histopathology (tubular atrophy, leukocyte infiltration, tubulointerstitial fibrosis, and global glomerulosclerosis) in patients with IgAN. Meanwhile, TLR7 mRNA levels were significantly increased in peripheral blood B cells of patients with IgAN. TLR7+CD19+ B cells expressed inflammatory cytokines (IL-6 and IL-12) in kidneys and produced high levels of IgA1 and galactose deficient-IgA1 (Gd-IgA1) in peripheral blood of patients with IgAN. Mechanistically, TLR7 activated B cells to produce high levels of Gd-IgA1 via the TLR7-GALNT2 axis in IgAN. Protein levels of GALNT2 were increased by overexpression of TLR7, while they were reduced by TLR7 knockdown in B cells. GALNT2 overexpression augmented Gd-IgA1 production in B cells derived from patients with IgAN. Taken together, high TLR7 expression in B cells has dual roles in the development and progression of IgAN, by facilitating renal inflammation and Gd-IgA1 antibody synthesis.
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MESH Headings
- Adolescent
- Adult
- Antigens, CD19/blood
- B-Lymphocytes/immunology
- B-Lymphocytes/pathology
- Biomarkers/blood
- Female
- Galactose/blood
- Gene Expression Regulation
- Glomerular Filtration Rate/genetics
- Glomerulonephritis, IGA/blood
- Glomerulonephritis, IGA/genetics
- Glomerulonephritis, IGA/immunology
- Glomerulonephritis, IGA/pathology
- Humans
- Immunity, Innate/genetics
- Immunoglobulin A/biosynthesis
- Immunoglobulin A/blood
- Immunoglobulin A/immunology
- Inflammation/blood
- Inflammation/genetics
- Inflammation/immunology
- Inflammation/pathology
- Kidney/metabolism
- Kidney/pathology
- Male
- Middle Aged
- N-Acetylgalactosaminyltransferases/blood
- RNA, Messenger/blood
- Renal Insufficiency, Chronic/blood
- Renal Insufficiency, Chronic/genetics
- Renal Insufficiency, Chronic/immunology
- Renal Insufficiency, Chronic/pathology
- Toll-Like Receptor 7/blood
- Young Adult
- Polypeptide N-acetylgalactosaminyltransferase
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Affiliation(s)
- Nuoyan Zheng
- Translational Medical Center and
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Kaifeng Xie
- Guangdong Medical University, Zhanjiang, Guangdong Province, China
| | - Hongjian Ye
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Yu Dong
- Department of Pathology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Bing Wang
- Guangzhou International Travel Health Care Center, Guangdong Province, China
| | - Ning Luo
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jinjin Fan
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jiaqing Tan
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Wei Chen
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xueqing Yu
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Medical University, Zhanjiang, Guangdong Province, China
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26
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Lee M, Suzuki H, Kato R, Fukao Y, Nakayama M, Kano T, Makita Y, Suzuki Y. Renal pathological analysis using galactose-deficient IgA1-specific monoclonal antibody is a strong tool for differentiation of primary IgA nephropathy from secondary IgA nephropathy. CEN Case Rep 2020; 10:17-22. [PMID: 32676896 PMCID: PMC7829275 DOI: 10.1007/s13730-020-00508-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 07/02/2020] [Indexed: 12/16/2022] Open
Abstract
In several cases with IgA nephropathy (IgAN), differential diagnosis is difficult due to the complication with other systemic diseases which can induce secondary IgAN. Recently, we demonstrated that immunostaining with galactose-deficient IgA1-specific monoclonal antibody (KM55 mAb) specifically showed positive in primary IgAN cases. Here, we report four cases which we could make definitive diagnosis by immunohistological analysis using KM55 mAb. The underlying systemic diseases are rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), hepatitis C (HCV) and Crohn’s disease (CD). Renal pathological findings in the four cases revealed mesangial proliferative glomerulonephritis with IgA and C3 deposits. Immunostaining with KM55 mAb was positive for three cases complicated with RA, SLE and CD, respectively. Thus, these three cases were diagnosed as primary IgAN and treated with tonsillectomy and steroid pulse therapy. These three cases finally achieved clinical remission. On the other hand, the case with HCV showed negative for KM55. Finally, we diagnosed as HCV-related nephropathy and successfully treated by antiviral agents. These cases suggested KM55 mAb is a strong tool to differentiate primary IgAN from secondary IgAN.
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MESH Headings
- Adult
- Antibodies, Monoclonal/immunology
- Antiviral Agents/administration & dosage
- Antiviral Agents/therapeutic use
- Arthritis, Rheumatoid/complications
- Arthritis, Rheumatoid/diagnosis
- Crohn Disease/complications
- Crohn Disease/diagnosis
- Diagnosis, Differential
- Female
- Galactose/deficiency
- Galactose/immunology
- Glomerulonephritis, IGA/diagnosis
- Glomerulonephritis, IGA/pathology
- Glomerulonephritis, Membranoproliferative/etiology
- Glomerulonephritis, Membranoproliferative/immunology
- Glomerulonephritis, Membranoproliferative/pathology
- Hepatitis C/complications
- Hepatitis C/diagnosis
- Humans
- Hydrocarbons, Fluorinated/immunology
- Immunoglobulin A/immunology
- Immunohistochemistry/methods
- Kidney/metabolism
- Kidney/pathology
- Kidney/ultrastructure
- Lupus Erythematosus, Systemic/complications
- Lupus Erythematosus, Systemic/diagnosis
- Male
- Middle Aged
- Pulse Therapy, Drug/methods
- Remission Induction
- Steroids/administration & dosage
- Steroids/therapeutic use
- Tonsillectomy/methods
- Urea/analogs & derivatives
- Urea/immunology
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Affiliation(s)
- Mingfeng Lee
- Department of Nephrology, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Hitoshi Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Rina Kato
- Department of Nephrology, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Yusuke Fukao
- Department of Nephrology, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Maiko Nakayama
- Department of Nephrology, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Toshiki Kano
- Department of Nephrology, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Yuko Makita
- Department of Nephrology, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Yusuke Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
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27
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Cambier A, Boyer O, Deschenes G, Gleeson J, Couderc A, Hogan J, Robert T. Steroid therapy in children with IgA nephropathy. Pediatr Nephrol 2020; 35:359-366. [PMID: 30778826 DOI: 10.1007/s00467-018-4189-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 12/20/2018] [Accepted: 12/21/2018] [Indexed: 01/14/2023]
Abstract
IgA nephropathy (IgAN) is one the most common primary glomerulonephritis in children and adolescents worldwide, with 20% of children developing end-stage kidney disease (ESKD) within 20 years of diagnosis. There is a need for treatment guidelines, especially for steroids in children with primary IgAN, since the STOP-IgA trial casts doubts on the use of steroids in adults with intermediate risk. Pediatricians are prone to prescribe steroids in addition to renin-angiotensin system blockade (RASB) when proteinuria is > 0.5 g/l, eGFR deteriorates < 70 ml/min/1.73 m2, or when a biopsy sample shows glomerular inflammation. Lack of randomized controlled trials (RCTs) in children with IgAN has led to an absence of consensus on the use of immunosuppressive agents in the treatment of progressive IgAN. This literature review evaluates the available evidence on steroid treatment in children with IgAN.
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Affiliation(s)
- Alexandra Cambier
- Pediatric Department of Nephrology and Transplantation, Assistance Publique-Hôpitaux de Paris, Hôpital Robert-Debré, Paris, France.
| | - Olivia Boyer
- Pediatric Department of Nephrology and Transplantation, Assistance Publique-Hôpitaux de Paris, Hôpital Necker, Paris, France
| | - Georges Deschenes
- Pediatric Department of Nephrology and Transplantation, Assistance Publique-Hôpitaux de Paris, Hôpital Robert-Debré, Paris, France
| | - James Gleeson
- Université Paris Diderot, Faculté de Médecine, Site Xavier Bichat, INSERM U1149 & CNRS ERL8252, Centre de Recherche sur l'Inflammation, Paris, France
| | - Anne Couderc
- Pediatric Department of Nephrology and Transplantation, Assistance Publique-Hôpitaux de Paris, Hôpital Robert-Debré, Paris, France
| | - Julien Hogan
- Pediatric Department of Nephrology and Transplantation, Assistance Publique-Hôpitaux de Paris, Hôpital Robert-Debré, Paris, France
| | - Thomas Robert
- Department of Nephrology, Transplantation and Emergency, Assistance Publique-Hôpitaux de Marseille, Hôpital de la Conception, Marseille, France.
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28
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Zachova K, Kosztyu P, Zadrazil J, Matousovic K, Vondrak K, Hubacek P, Julian BA, Moldoveanu Z, Novak Z, Kostovcikova K, Raska M, Mestecky J. Role of Epstein-Barr Virus in Pathogenesis and Racial Distribution of IgA Nephropathy. Front Immunol 2020; 11:267. [PMID: 32184780 PMCID: PMC7058636 DOI: 10.3389/fimmu.2020.00267] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 02/03/2020] [Indexed: 02/04/2023] Open
Abstract
IgA nephropathy (IgAN) is the dominant type of primary glomerulonephritis worldwide. However, IgAN rarely affects African Blacks and is uncommon in African Americans. Polymeric IgA1 with galactose-deficient hinge-region glycans is recognized as auto-antigen by glycan-specific antibodies, leading to formation of circulating immune complexes with nephritogenic consequences. Because human B cells infected in vitro with Epstein-Barr virus (EBV) secrete galactose-deficient IgA1, we examined peripheral blood B cells from adult IgAN patients, and relevant controls, for the presence of EBV and their phenotypic markers. We found that IgAN patients had more lymphoblasts/plasmablasts that were surface-positive for IgA, infected with EBV, and displayed increased expression of homing receptors for targeting the upper respiratory tract. Upon polyclonal stimulation, these cells produced more galactose-deficient IgA1 than did cells from healthy controls. Unexpectedly, in healthy African Americans, EBV was detected preferentially in surface IgM- and IgD-positive cells. Importantly, most African Blacks and African Americans acquire EBV within 2 years of birth. At that time, the IgA system is naturally deficient, manifested as low serum IgA levels and few IgA-producing cells. Consequently, EBV infects cells secreting immunoglobulins other than IgA. Our novel data implicate Epstein-Barr virus infected IgA+ cells as the source of galactose-deficient IgA1 and basis for expression of relevant homing receptors. Moreover, the temporal sequence of racial-specific differences in Epstein-Barr virus infection as related to the naturally delayed maturation of the IgA system explains the racial disparity in the prevalence of IgAN.
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Affiliation(s)
- Katerina Zachova
- Department of Immunology, Faculty of Medicine and Dentistry, University Hospital Olomouc, Palacky University Olomouc, Olomouc, Czechia
| | - Petr Kosztyu
- Department of Immunology, Faculty of Medicine and Dentistry, University Hospital Olomouc, Palacky University Olomouc, Olomouc, Czechia
| | - Josef Zadrazil
- Department of Internal Medicine III Nephrology, Rheumatology and Endocrinology, University Hospital Olomouc, Palacky University Olomouc, Olomouc, Czechia
| | - Karel Matousovic
- Department of Medicine, Second Faculty of Medicine, University Hospital Motol, Charles University, Prague, Czechia
| | - Karel Vondrak
- Department of Pediatrics, Second Faculty of Medicine, Charles University, Prague, Czechia
| | - Petr Hubacek
- Department of Medical Microbiology, Second Faculty of Medicine, University Hospital Motol, Charles University, Prague, Czechia
| | - Bruce A Julian
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Zina Moldoveanu
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Zdenek Novak
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Klara Kostovcikova
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology, Czech Academy of Sciences, Prague, Czechia
| | - Milan Raska
- Department of Immunology, Faculty of Medicine and Dentistry, University Hospital Olomouc, Palacky University Olomouc, Olomouc, Czechia.,Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jiri Mestecky
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States.,Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States.,Laboratory of Cellular and Molecular Immunology, Institute of Microbiology, Czech Academy of Sciences, Prague, Czechia
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29
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Specific strains of Streptococcus mutans, a pathogen of dental caries, in the tonsils, are associated with IgA nephropathy. Sci Rep 2019; 9:20130. [PMID: 31882880 PMCID: PMC6934739 DOI: 10.1038/s41598-019-56679-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 12/17/2019] [Indexed: 02/06/2023] Open
Abstract
Streptococcus mutans is known to be a major causative agent of dental caries, and strains expressing the cell surface collagen-binding Cnm protein contribute to the development of several systemic diseases. A relationship between tonsillar immunity and glomerulonephritis has been recognized in IgA nephropathy (IgAN), and specific pathogens may have effects on tonsillar immunity (mucosal immunity). Here, we present findings showing a relationship between the presence of Cnm-positive S. mutans strains in the tonsils of IgAN patients and IgAN condition/pathogenesis. Analyses of tonsillar specimens obtained from patients with IgAN (n = 61) and chronic tonsillitis (controls; n = 40) showed that the Cnm protein-positive rate was significantly higher in IgAN patients. Among IgAN patients, the tonsillar Cnm-positive group (n = 15) had a significantly higher proportion of patients with high urinary protein (>1.5 g/gCr) and lower serum albumin level than the Cnm-negative group (n = 46). Additionally, Cnm protein and CD68, a common human macrophage marker, were shown to be merged in the tonsils of IgAN patients. These findings suggest that Cnm-positive S. mutans strains in the tonsils may be associated with severe IgAN.
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30
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Taherkhani A, Farrokhi Yekta R, Mohseni M, Saidijam M, Arefi Oskouie A. Chronic kidney disease: a review of proteomic and metabolomic approaches to membranous glomerulonephritis, focal segmental glomerulosclerosis, and IgA nephropathy biomarkers. Proteome Sci 2019; 17:7. [PMID: 31889913 PMCID: PMC6925425 DOI: 10.1186/s12953-019-0155-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 12/12/2019] [Indexed: 12/12/2022] Open
Abstract
Chronic Kidney Disease (CKD) is a global health problem annually affecting millions of people around the world. It is a comprehensive syndrome, and various factors may contribute to its occurrence. In this study, it was attempted to provide an accurate definition of chronic kidney disease; followed by focusing and discussing on molecular pathogenesis, novel diagnosis approaches based on biomarkers, recent effective antigens and new therapeutic procedures related to high-risk chronic kidney disease such as membranous glomerulonephritis, focal segmental glomerulosclerosis, and IgA nephropathy, which may lead to end-stage renal diseases. Additionally, a considerable number of metabolites and proteins that have previously been discovered and recommended as potential biomarkers of various CKDs using ‘-omics-’ technologies, proteomics, and metabolomics were reviewed.
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Affiliation(s)
- Amir Taherkhani
- 1Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | | | - Maede Mohseni
- 3Urology and Nephrology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Massoud Saidijam
- 1Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Afsaneh Arefi Oskouie
- 4Department of Basic Sciences, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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31
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TLR9 activation induces aberrant IgA glycosylation via APRIL- and IL-6-mediated pathways in IgA nephropathy. Kidney Int 2019; 97:340-349. [PMID: 31748116 DOI: 10.1016/j.kint.2019.08.022] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 07/30/2019] [Accepted: 08/16/2019] [Indexed: 12/13/2022]
Abstract
Galactose-deficient IgA1 (Gd-IgA1) plays a crucial role in the development of IgA nephropathy (IgAN). However, the pathogenic mechanisms driving Gd-IgA1 production have not been fully elucidated. Innate-immune activation via Toll-like receptor 9 (TLR9) is known to be involved in Gd-IgA1 production. A proliferation inducing ligand (APRIL) and IL-6 are also known to enhance Gd-IgA1 synthesis in IgAN. With this as background, we investigated how TLR9 activation in IgA secreting cells results in overproduction of nephritogenic IgA in the IgAN-prone ddY mouse and in human IgA1-secreting cells. Injection of the TLR9 ligand CpG-oligonucleotides increased production of aberrantly glycosylated IgA and IgG-IgA immune complexes in ddY mice that, in turn, exacerbated kidney injury. CpG-oligonucleotide-stimulated mice had elevated serum levels of APRIL that correlated with those of aberrantly glycosylated IgA and IgG-IgA immune complexes. In vitro, TLR9 activation enhanced production of the nephritogenic IgA as well as APRIL and IL-6 in splenocytes of ddY mice and in human IgA1-secreting cells. However, siRNA knock-down of APRIL completely suppressed overproduction of Gd-IgA1 induced by IL-6. Neutralization of IL-6 decreased CpG-oligonucleotide-induced overproduction of Gd-IgA1. Furthermore, APRIL and IL-6 pathways each independently mediated TLR9-induced overproduction of Gd-IgA1. Thus, TLR9 activation enhanced synthesis of aberrantly glycosylated IgA that, in a mouse model of IgAN, further enhanced kidney injury. Hence, APRIL and IL-6 synergistically, as well as independently, enhance synthesis of Gd-IgA1.
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Does the renal expression of Toll-like receptors play a role in patients with IgA nephropathy? J Nephrol 2019; 33:307-316. [PMID: 31489594 DOI: 10.1007/s40620-019-00640-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 08/14/2019] [Indexed: 12/26/2022]
Abstract
The onset of IgA nephropathy (IgAN), characterized by glomerular deposition of IgA-containing immune complexes, is often associated with synpharyngitic hematuria. Innate immune responses mediated by Toll-like receptors (TLR) may play a role in IgAN onset and/or progression. Here, we assessed the expression of TLR 4, 7, 8, and 9 in renal-biopsy specimens from patients with IgAN, with different degree of proteinuria and eGFR, compared with normal-kidney and disease-control tissues (ANCA-associated vasculitis). Renal-biopsy specimens from 34 patients with IgAN and 7 patients with ANCA-associated vasculitis were used. In addition, we used 15 healthy portions of renal-tissue specimens from kidneys after nephrectomy for cancer as control specimens. Expression of TLR 4, 7, 8, and 9 was assessed using immunohistochemical staining of paraffin-embedded renal-biopsy tissue specimens with specific antibodies and evaluated semiquantitatively by light microscopy. Linear discriminant analysis (LDA) was used to test whether intrarenal staining of TLR 4, 7, 8, and 9 distinguished patients with IgAN from controls or correlated with eGFR and/or proteinuria. eGFR was calculated using the creatinine-based formula. Moreover, the biopsies from patients with IgAN were scored according to the Oxford Classification. LDA showed that staining for TLR 4, 7, 8, and 9 was more intense in specimens from IgAN patients compared to normal kidney tissues. The intensity of intrarenal staining of TLRs discriminated four groups of IgAN patients with different eGFR and proteinuria and MEST scoring.
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Abstract
IgA nephropathy (IgAN) is one of the most common primary glomerulonephritides throughout the world and a major cause of end-stage renal disease among the East Asian population. It is widely considered that genetic factors play an important role in the pathogenesis of IgAN. This article summarizes the recent achievements in the genetic studies of IgAN, focusing mainly on studies performed in East Asia, from the early association studies of candidate genes and family based designs, to the recent genome-wide association studies. There have been five large genome-wide association studies performed that have identified multiple susceptibility loci for IgAN, especially some novel loci identified in the Chinese population. Genes within these loci have provided important insights into the potential biological mechanisms and pathways that influence genetic risk to IgAN. In susceptibility loci/genes, the study of genetic interaction and structural variants (such as copy number variation) was conducted to identify more variants associated with IgAN and disease progression. Genetic studies of IgAN from East Asia have made great achievements over the years. Most susceptibility loci discovered to date encode genes involved in the response to mucosal pathogens, suggesting that an intestinal-immune network for IgA production may be involved in the pathogenesis of IgAN. Although genetic studies of the complex diseases are challenging, for future genetic studies in IgAN, new genetic techniques and methods of analysis, especially next-generation sequencing, need to be applied to push the genetic studies forward.
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Affiliation(s)
- Ming Li
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.; Key Laboratory of Nephrology, National Health Commission (NHC) and Guangdong Province, Guangzhou, Guangdong, China
| | - Xue-Qing Yu
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.; Key Laboratory of Nephrology, National Health Commission (NHC) and Guangdong Province, Guangzhou, Guangdong, China.; Guangdong Medical University, Zhanjiang, Guangdong, China..
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New strategies and perspectives on managing IgA nephropathy. Clin Exp Nephrol 2019; 23:577-588. [PMID: 30756248 PMCID: PMC6469670 DOI: 10.1007/s10157-019-01700-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 01/17/2019] [Indexed: 12/23/2022]
Abstract
IgA nephropathy is an inflammatory renal disease characterised by the deposition of IgA in the glomerular mesangium and is the most commonly reported primary glomerulonephritis worldwide. Thirty to forty percent of patients with the disease develop progressive renal function decline, requiring renal replacement therapy within two decades of diagnosis. Despite this, accurate individual risk stratification at diagnosis and predicting treatment response remains a challenge. Furthermore, there are currently no disease specific treatments currently licensed to treat the condition due to long standing challenges in the nature and prevalence of the disease. Despite this, there have been exciting recent advances in the field that may represent paradigm shifts in the way IgA nephropathy is managed in the near future. In this review, we explore the evidence base informing current approaches to management and explore new strategies and future directions in the diagnosis and management of IgA nephropathy.
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Abstract
PURPOSE OF REVIEW Immunoglobulin A (IgA) nephropathy (IgAN) is a heterogeneous disease, and predicting individual patient risk of renal progression is challenging. Recent studies provide new evidence regarding the use of clinical, histologic, and biomarker predictors of renal outcome in IgAN. RECENT FINDINGS A meta-analysis of clinical trials demonstrated that early change in proteinuria is a valid surrogate outcome measure for longer term decline in renal function, which supports the use of proteinuria to dynamically re-evaluate patient prognosis over time. The MEST histologic classification has been further validated in a large European cohort. An international multiethnic observational study demonstrated that crescents are independently associated with renal outcome, and as a result a crescent score (<25% versus >25% of glomeruli) has been added to MEST. Proteinuria, estimated glomerular filtration rate (GFR), and blood pressure at the time of biopsy can be used to accurately predict prognosis when combined with MEST, instead of using 2 years of follow-up data. Currently, no available risk prediction model that combines clinical and histologic predictors has been sufficiently validated for routine use. There are multiple biomarkers that have been studied in IgAN, however none have been externally validated and shown to improve prediction beyond clinical and histologic risk factors. SUMMARY Proteinuria, estimated GFR, blood pressure, and the MEST-C score are the most readily available risk factors to predict renal prognosis in IgAN. Future research is required to develop and validate methods of integrating these risk factors together to accurately risk stratify individual patients, and provide the framework for evaluating biomarkers capable of further improving risk prediction.
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Tomino Y. How to treat patients with chronic kidney disease: With special focus on IgA nephropathy. Nephrology (Carlton) 2019; 23 Suppl 4:76-79. [PMID: 30298660 DOI: 10.1111/nep.13471] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/01/2018] [Indexed: 01/06/2023]
Abstract
Chronic kidney disease has become a worldwide problem. Among chronic kidney disease patients, IgA nephropathy is common in the world. Serum levels of galactose deficient (Gd)-IgA1 and Gd-IgA1-specific antibodies are elevated in most IgA nephropathy patients. Glomerular Gd-IgA1 deposition has been observed by immunofluorescence. There are many reports that the anti-proteinuric effect is significantly greater in groups who receive tonsillectomy with steroid pulse therapy in IgA nephropathy patients. Furthermore, patients with tonsillectomy with steroid pulse therapy have shown a strong down-regulation of delta serum IgA/C3 per year and have conserved their renal function. New treatments, that is, Atacicept and glucocorticoid budesonide, have been developed for this disease.
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Affiliation(s)
- Yasuhiko Tomino
- Juntendo University, Tokyo, Japan.,Asian Pacific Renal Research Promotion Office, Medical Corporation SHOWAKAI, Tokyo, Japan
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Wada Y, Matsumoto K, Suzuki T, Saito T, Kanazawa N, Tachibana S, Iseri K, Sugiyama M, Iyoda M, Shibata T. Clinical significance of serum and mesangial galactose-deficient IgA1 in patients with IgA nephropathy. PLoS One 2018; 13:e0206865. [PMID: 30388165 PMCID: PMC6214568 DOI: 10.1371/journal.pone.0206865] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 10/19/2018] [Indexed: 12/29/2022] Open
Abstract
Introduction Galactose-deficient IgA1 (Gd-IgA1) is a critical pathogenic factor for IgA nephropathy (IgAN), but its value as a disease-specific biomarker remains controversial. We aimed to clarify the clinical significance of Gd-IgA1 in patients with IgAN. Methods We retrospectively reviewed 111 patients who were diagnosed with IgAN based on the findings of renal biopsies (RB) at Showa University Hospital since 2007. Serum Gd-IgA1 (s-Gd-IgA1) at the time of RB was compared among 111 IgAN patients, 18 Henoch-Schönlein purpura nephritis (HSPN) patients, 29 lupus nephritis (LN) patients, 28 ANCA-associated vasculitis (AAV) patients, and 13 minimal change disease (MCD) patients using ELISA with an anti-human Gd-IgA1-specific monoclonal antibody (KM55). We also immunohistochemically stained paraffin-embedded sections for mesangial Gd-IgA1 (m-Gd-IgA1) deposition using KM55. Results Although levels of s-Gd-IgA1 were comparable among IgAN and HSPN, s-Gd-IgA1 levels were significantly elevated in patients with IgAN compared with LN, AAV and MCD (IgAN vs. HSPN, LN, AAV, and MCD: 16.2 ± 9.1 vs. 14.2 ± 10.8, p = 0.263; 12.7 ± 9.4, p = 0.008; 13.1 ± 7.3, p = 0.059; and 8.2 ± 4.8 μg/mL, p<0.001, respectively). Mesangial-Gd-IgA1 deposition was specifically detected in IgAN or HSPN. The increase in s-Gd-IgA1 significantly correlated with m-Gd-IgA1 positivity in patients with IgAN, and s-Gd-IgA1 elevation and m-Gd-IgA1 deposition were evident in patients with histopathologically advanced IgAN. Moreover, s-Gd-IgA1 levels were significantly higher in IgAN patients with glomerular sclerosis and tubulo-interstitial lesions. Mesangial-Gd-IgA1 intensity negatively correlated with eGFR in IgAN. Multivariate analysis selected s-Gd-IgA1 elevation as a significant risk factor for a 30%-reduction in eGFR in IgAN (HR, 1.37; 95% CI, 1.02–1.89; p = 0.038). Conclusions Although IgAN and HSPN remain difficult to differentiate, s-Gd-IgA1 elevation and m-Gd-IgA1 deposition are reliable diagnostic factors that reflect IgAN severity. Serum-Gd-IgA1 could serve as a predictor of renal outcomes in IgAN. Thus, Gd-IgA1 could be significant biomarker for patients with IgAN.
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Affiliation(s)
- Yukihiro Wada
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
- * E-mail:
| | - Kei Matsumoto
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Taihei Suzuki
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Tomohiro Saito
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Nobuhiro Kanazawa
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Shohei Tachibana
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Ken Iseri
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Motonori Sugiyama
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Masayuki Iyoda
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Takanori Shibata
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
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Monteiro RC. Recent advances in the physiopathology of IgA nephropathy. Nephrol Ther 2018; 14 Suppl 1:S1-S8. [PMID: 29606255 DOI: 10.1016/j.nephro.2018.02.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 02/01/2018] [Indexed: 01/01/2023]
Abstract
Immunoglobulin A nephropathy or Berger's disease is the most common type of primary glomerulonephritis, which is characterized by IgA1-containing immune-deposits in the glomerular mesangium. Microscopic haematuria and proteinuria are the most common presentations. Mesangial cell proliferation with IgA deposition is found on renal biopsy. Mechanims of the disease implicate at least four key molecules have been implicated in immune complex formation: galactose-deficient IgA1, autoantibodies anti-galactose-deficient-IgA1, soluble CD89 (Fc receptor for IgA) and the CD71 mesangial IgA receptor (transferrin receptor). These factors associated with environmental factors (antigens, food and microbiota) are correlated with disease progression and recurrence after transplantation. This review exploits recent data on the role of these molecular players of the disease, which may improve future therapeutic management of immunoglobulin A nephropathy.
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Affiliation(s)
- Renato C Monteiro
- Inserm U1149 centre de recherche sur l'inflammation, 16, rue Henri-Huchard, 75018 Paris, France; CNRS ERL8252, 16, rue Henri-Huchard, 75018 Paris, France; Laboratoire d'excellence Inflamex, faculté de médecine Bichat, université Paris-Diderot, 16, rue Henri-Huchard, 75018 Paris, France; Service d'immunologie, DHU Fire, hôpital Bichat, 16, rue Henri-Huchard, 75018 Paris, France.
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Abstract
IgA nephropathy, the most common primary glomerulonephritis in the world and a frequent cause of end-stage renal disease, is characterized by typical mesangial deposits of IgA1, as described by Berger and Hinglaise in 1968. Since then, it has been discovered that aberrant IgA1 O-glycosylation is involved in disease pathogenesis. Progress in glycomic, genomic, clinical, analytical, and biochemical studies has shown autoimmune features of IgA nephropathy. The autoimmune character of the disease is explained by a multihit pathogenesis model, wherein overproduction of aberrantly glycosylated IgA1, galactose-deficient in some O-glycans, by IgA1-secreting cells leads to increased levels of circulatory galactose-deficient IgA1. These glycoforms induce production of autoantibodies that subsequently bind hinge-region of galactose-deficient IgA1 molecules, resulting in the formation of nephritogenic immune complexes. Some of these complexes deposit in the kidney, activate mesangial cells, and incite glomerular injury. Thus, galactose-deficient IgA1 is central to the disease process. In this article, we review studies concerning IgA1 O-glycosylation that have contributed to the current understanding of the role of IgA1 in the pathogenesis of IgA nephropathy.
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Affiliation(s)
- Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL..
| | - Jonathan Barratt
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK
| | - Bruce A Julian
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL.; Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - Matthew B Renfrow
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL
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Kohagura K, Arima H, Miyasato H, Chang TH, Yamazato M, Kobori H, Nishiyama A, Iseki K, Ohya Y. Add-On Effect of Angiotensin Receptor Blockade (Candesartan) on Clinical Remission in Active IgA Nephropathy Patients Treated with Steroid Pulse Therapy and Tonsillectomy: a Randomized, Parallel-Group Comparison Trial. Kidney Blood Press Res 2018; 43:780-792. [PMID: 29794482 PMCID: PMC6019550 DOI: 10.1159/000489914] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 05/09/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS Angiotensin receptor blockers (ARBs) may be beneficial for clinical remission during conventional therapy with tonsillectomy and steroid pulse (TSP) for active IgA nephropathy. METHODS Seventy-seven patients with active IgA nephropathy were randomly assigned to the control arm with conventional regimen (TSP followed by oral prednisolone) (n = 37) or the ARB arm with conventional regimen plus ARB candesartan for the first 6 months (n = 40). Patients not achieving proteinuria remission at 12 months in either arm were administered candesartan, which was titrated until the 24-month follow-up. The primary endpoints were remission of proteinuria (< 0.3 g/gCr) and hematuria at 12 months. RESULTS Baseline proteinuria (g/g Cr) were comparable between the control and ARB arm (1.02 vs. 0.97, P = 0.97). Similarly, cumulative remission rates at 6, 12, and 24 months were comparable between the control and ARB arms (37.8% vs. 35% [P = 0.80], 48.7% vs. 38.5% [P = 0.37], 71.4% vs. 51.3% [P = 0.08]). Proteinuria, which was slightly worse in the control arm than in the ARB arm at 6 months, was comparable afterwards (0.20 vs. 0.23 g/g Cr at 12 months; 0.12 vs. 0.13 g/g Cr at 24 months). Significant reductions observed in urinary angiotensinogen were almost comparable between the two treatment arms at both 6 and 12 months. CONCLUSION Early candesartan treatment combined with TSP may not benefit clinical remission regardless of the blood pressure. ARB titration later during the treatment might provide benefit for patients with active IgA nephropathy.
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Affiliation(s)
- Kentaro Kohagura
- Dialysis Unit, University of the Ryukyus Hospital, Okinawa, Japan,
- Department of Cardiovascular Medicine, Nephrology and Neurology, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan,
| | - Hisatomi Arima
- Department of Preventive Medicine and Public Health, Fukuoka University, Fukuoka, Japan
| | | | | | | | - Hiroyuki Kobori
- Departments of Pharmacology and Nephrology, School of Medicine, International University of Health and Welfare, Narita, Japan
| | - Akira Nishiyama
- Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | | | - Yusuke Ohya
- Department of Cardiovascular Medicine, Nephrology and Neurology, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
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Suzuki H. Biomarkers for IgA nephropathy on the basis of multi-hit pathogenesis. Clin Exp Nephrol 2018; 23:26-31. [PMID: 29740706 PMCID: PMC6344607 DOI: 10.1007/s10157-018-1582-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 03/26/2018] [Indexed: 01/06/2023]
Abstract
IgA nephropathy (IgAN) is the most prevalent glomerular disease worldwide and is associated with a poor prognosis. Development of curative treatment strategies and approaches for early diagnosis is necessary. Renal biopsy is the gold standard for the diagnosis and assessment of disease activity. However, reliable biomarkers are needed for the noninvasive diagnosis of this disease and to more fully delineate the risk of progression. With regard to the pathogenesis of IgAN, the multi-hit hypothesis, including production of galactose-deficient IgA1 (Gd-IgA1; Hit 1), IgG or IgA autoantibodies that recognize Gd-IgA1 (Hit 2), and their subsequent immune complexes formation (Hit 3) and glomerular deposition (Hit 4), has been widely supported by many studies. Although the prognostic values of several biomarkers have been discussed, we recently developed a highly sensitive and specific diagnostic method by measuring serum levels of Gd-IgA1 and Gd-IgA1-containing immune complexes. In addition, urinary Gd-IgA1 may represent a disease-specific biomarker for IgAN. We also confirmed that there is a significant correlation between serum levels of these effector molecules and disease activity, suggesting that each can be considered a practical surrogate marker of therapeutic response. Thus, these disease-oriented specific serum and urine biomarkers may be useful for screening of potential IgAN with isolated hematuria, earlier diagnosis, disease activity, and eventually, response to treatment. In this review, we discuss these concepts, with a focus on potential clinical applications of these biomarkers.
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Affiliation(s)
- Hitoshi Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan.
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Yang P, Zou H, Xiao B, Xu G. Comparative Efficacy and Safety of Therapies in IgA Nephropathy: A Network Meta-analysis of Randomized Controlled Trials. Kidney Int Rep 2018; 3:794-803. [PMID: 29989013 PMCID: PMC6035132 DOI: 10.1016/j.ekir.2018.03.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 02/23/2018] [Accepted: 03/12/2018] [Indexed: 11/16/2022] Open
Abstract
The present study aims to compare the relative efficacy and safety of different interventions for IgA nephropathy (IgAN) with proteinuria more than 1 g/d by using network meta-analysis. We searched PubMed, Embase, and the Cochrane Library for studies compared the rate of clinical remission and/or end-stage renal disease (ESRD) and/or serious adverse events in IgAN patients with proteinuria (>1 g/d). The surface under the cumulative ranking area (SUCRA) was calculated to rank the interventions. A total of 21 randomized controlled trials with 1822 participants were included for the comparisons of 7 interventions. The rank of the most effective treatments to induce clinical remission was renin−angiotensin system inhibitors (RASi) plus urokinase, steroid plus tonsillectomy, and RASi plus steroid with a SUCRA of 0.912, 0.710, and 0.583, respectively. As for the prevention of ESRD or doubling of serum creatinine, RASi plus steroid (SUCRA 0.012) was the most effective, followed by RASi (SUCRA 0.282) and steroid (SUCRA 0.494), leaving mycophenolate mofetil as the least effective (SUCRA 0.644). There was no statistical difference among all interventions in the occurrence of serious adverse events. The current network meta-analysis demonstrated for the first time that RASi plus steroid is probably the best therapeutic choice, not only for reducing proteinuria but also for maintaining long-term renal protection.
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Affiliation(s)
- Pingping Yang
- Department of Nephrology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Honghong Zou
- Department of Nephrology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Bufan Xiao
- Grade 2014, the First Clinical Medical College of Nanchang University, Nanchang, China
| | - Gaosi Xu
- Department of Nephrology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
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43
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Al-Lawati AI, Reich HN. Is there a role for immunosuppression in immunoglobulin A nephropathy? Nephrol Dial Transplant 2017; 32:i30-i36. [PMID: 28391341 DOI: 10.1093/ndt/gfw342] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 08/18/2016] [Indexed: 01/31/2023] Open
Abstract
The most common primary glomerular disease globally is IgA nephropathy (IgAN). It is often a slowly progressive disease, and ∼40% of patients will progress to kidney failure. Due to a lack of large clinical trial networks and a lack of surrogate markers of treatment efficacy, there are relatively few large multicenter clinical trials in IgAN. Given that both the pathogenesis and progression of IgAN are linked to defects in mucosal immune regulation and inflammation, use of immunosuppression to prevent kidney failure is well founded. However, recent clinical trials have supported improvement in disease parameters, but this has not always translated to parallel amelioration in longer-term outcome. In this review we summarize the most current clinical research examining the efficacy of immunosuppression in IgAN.
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Affiliation(s)
- Ali I Al-Lawati
- Division of Nephrology, Toronto Glomerulonephritis Registry, University Health Network, Toronto, Canada.,Sultan Qaboos University Hospital, Muscat, Oman
| | - Heather N Reich
- Division of Nephrology, Toronto Glomerulonephritis Registry, University Health Network, Toronto, Canada.,Gabor Zellerman Chair in Nephrology Research, University of Toronto, Toronto, Canada
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Muto M, Manfroi B, Suzuki H, Joh K, Nagai M, Wakai S, Righini C, Maiguma M, Izui S, Tomino Y, Huard B, Suzuki Y. Toll-Like Receptor 9 Stimulation Induces Aberrant Expression of a Proliferation-Inducing Ligand by Tonsillar Germinal Center B Cells in IgA Nephropathy. J Am Soc Nephrol 2016; 28:1227-1238. [PMID: 27920152 DOI: 10.1681/asn.2016050496] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Accepted: 10/04/2016] [Indexed: 12/25/2022] Open
Abstract
The TNF family member a proliferation-inducing ligand (APRIL; also known as TNFSF13), produced by myeloid cells, participates in the generation and survival of antibody-producing plasma cells. We studied the potential role of APRIL in the pathogenesis of IgA nephropathy (IgAN). We found that a significant proportion of germinal centers (GCs) in tonsils of patients with IgAN contained cells aberrantly producing APRIL, contributing to an overall upregulation of tonsillar APRIL expression compared with that in tonsils of control patients with tonsillitis. In IgAN GC, antigen-experienced IgD-CD38+/-CD19+ B cells expressing a switched IgG/IgA B cell receptor produced APRIL. Notably, these GC B cells expressed mRNA encoding the common cleavable APRIL-α but also, the less frequent APRIL-δ/ζ mRNA, which encodes a protein that lacks a furin cleavage site and is, thus, the uncleavable membrane-bound form. Significant correlation between TLR9 and APRIL expression levels existed in tonsils from patients with IgAN. In vitro, repeated TLR9 stimulation induced APRIL expression in tonsillar B cells from control patients with tonsillitis. Clinically, aberrant APRIL expression in tonsillar GC correlated with greater proteinuria, and patients with IgAN and aberrant APRIL overexpression in tonsillar GC responded well to tonsillectomy, with parallel decreases in serum levels of galactose-deficient IgA1. Taken together, our data indicate that antibody disorders in IgAN associate with TLR9-induced aberrant expression of APRIL in tonsillar GC B cells.
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Affiliation(s)
- Masahiro Muto
- Division of Nephrology, Department of Internal Medicine, Juntendo University, Tokyo, Japan
| | - Benoit Manfroi
- Analytical Immunology for Chronic Pathologies, Albert Bonniot Institute, Institut National de la Santé et de la Recherche Médicale/University Joseph Fourier U823, Grenoble, France
| | - Hitoshi Suzuki
- Division of Nephrology, Department of Internal Medicine, Juntendo University, Tokyo, Japan
| | - Kensuke Joh
- Department of Pathology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masaaki Nagai
- Division of Nephrology and Diabetology, Narita Memorial Hospital, Toyohashi, Japan
| | - Sachiko Wakai
- Department of Internal Medicine, Tokyo Metropolitan Health and Medical Treatment Corporation, Okubo Hospital, Tokyo, Japan
| | - Christian Righini
- Department of Otolaryngology, Head and Neck Surgery, Grenoble University Hospital, Grenoble, France; and
| | - Masayuki Maiguma
- Division of Nephrology, Department of Internal Medicine, Juntendo University, Tokyo, Japan
| | - Shozo Izui
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Yasuhiko Tomino
- Division of Nephrology, Department of Internal Medicine, Juntendo University, Tokyo, Japan
| | - Bertrand Huard
- Analytical Immunology for Chronic Pathologies, Albert Bonniot Institute, Institut National de la Santé et de la Recherche Médicale/University Joseph Fourier U823, Grenoble, France;
| | - Yusuke Suzuki
- Division of Nephrology, Department of Internal Medicine, Juntendo University, Tokyo, Japan;
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Rasche FM, Keller F, Rasche WG, Schiekofer S, Boldt A, Sack U, Fahnert J. Why, when and how should immunosuppressive therapy considered in patients with immunoglobulin A nephropathy? Clin Exp Immunol 2016; 186:115-133. [PMID: 27283488 PMCID: PMC5054563 DOI: 10.1111/cei.12823] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 05/20/2016] [Accepted: 05/20/2016] [Indexed: 12/13/2022] Open
Abstract
IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. Lifelong mesangial deposition of IgA1 complexes subsist inflammation and nephron loss, but the complex pathogenesis in detail remains unclear. In regard to the heterogeneous course, classical immunosuppressive and specific therapeutic regimens adapted to the loss of renal function will here be discussed in addition to the essential common renal supportive therapy. Renal supportive therapy alleviates secondary, surrogate effects or sequelae on renal function and proteinuria of high intraglomerular pressure and subsequent nephrosclerosis by inhibition of the renin angiotensin system (RAASB). In patients with physiological (ΔGFR < 1·5 ml/min/year) or mild (ΔGFR 1·5-5 ml/min/year) decrease of renal function and proteinuric forms (> 1 g/day after RAASB), corticosteroids have shown a reduction of proteinuria and might protect further loss of renal function. In patients with progressive loss of renal function (ΔGFR > 3 ml/min within 3 months) or a rapidly progressive course with or without crescents in renal biopsy, cyclophosphamide with high-dose corticosteroids as induction therapy and azathioprine maintenance has proved effective in one randomized controlled study of a homogeneous cohort in loss of renal function (ΔGFR). Mycophenolic acid provided further maintenance in non-randomized trials. Differentiated, precise, larger, randomized, placebo-controlled studies focused on the loss of renal function in the heterogeneous forms of IgAN are still lacking. Prospectively, fewer toxic agents will be necessary in the treatment of IgAN.
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Affiliation(s)
- F M Rasche
- Department of Internal Medicine, Neurology, Dermatology, Clinic for Endocrinology, Nephrology, Section of Nephrology, University Leipzig, Leipzig, Germany
| | - F Keller
- Department of Internal Medicine I, Division of Nephrology, University Hospital of Ulm, Ulm, Germany.
| | - W G Rasche
- Department of Head Medicine and Oral Health, Department of Ophthalmology, University Leipzig, Leipzig, Germany
| | - S Schiekofer
- Center for Geriatric Medicine at Bezirksklinikum Regensburg, Department of Psychiatry and Psychotherapy, University Regensburg, Regensburg, Germany
| | - A Boldt
- Institute of Clinical Immunology, Medical Faculty, Leipzig, Germany
| | - U Sack
- Institute of Clinical Immunology, Medical Faculty, Leipzig, Germany
| | - J Fahnert
- Department of Diagnostic and Interventional Radiology, University Leipzig, Leipzig, Germany
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Toward Noninvasive Diagnosis of IgA Nephropathy: A Pilot Urinary Metabolomic and Proteomic Study. DISEASE MARKERS 2016; 2016:3650909. [PMID: 27799660 PMCID: PMC5075301 DOI: 10.1155/2016/3650909] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 08/02/2016] [Accepted: 08/18/2016] [Indexed: 11/17/2022]
Abstract
IgA nephropathy is diagnosed by renal biopsy, an invasive procedure with a risk of significant complications. Noninvasive approaches are needed for possible diagnostic purposes and especially for monitoring disease activity or responses to treatment. In this pilot project, we assessed the utility of urine samples as source of biomarkers of IgA nephropathy. We used spot urine specimens from 19 healthy controls, 11 patients with IgA nephropathy, and 8 renal-disease controls collected on day of renal biopsy. Urine samples were analyzed using untargeted metabolomic and targeted proteomic analyses by several experimental techniques: liquid chromatography coupled with mass spectrometry, immunomagnetic isolation of target proteins coupled with quantitation by mass spectrometry, and protein arrays. No single individual biomarker completely differentiated the three groups. Therefore, we tested the utility of several markers combined in a panel. Discriminant analysis revealed that combination of seven markers, three metabolites (dodecanal, 8-hydroxyguanosine, and leukotriene C4), three proteins (α1-antitrypsin, IgA-uromodulin complex, and galactose-deficient IgA1), and heparan sulfate, differentiated patients with IgA nephropathy from patients with other renal diseases and healthy controls. Future studies are needed to validate these preliminary findings and to determine the power of these urinary markers for assessment of responses to therapy.
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Tomino Y. Diagnosis and treatment of patients with IgA nephropathy in Japan. Kidney Res Clin Pract 2016; 35:197-203. [PMID: 27957413 PMCID: PMC5142264 DOI: 10.1016/j.krcp.2016.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 08/25/2016] [Accepted: 09/02/2016] [Indexed: 01/27/2023] Open
Abstract
Chronic kidney disease (CKD) is a worldwide public health problem that affects millions of people from all racial and ethnic groups. Although CKD is not one specific disease, it is a comprehensive syndrome that includes IgA nephropathy. As reported by the Japanese Society of Nephrology, 13.0 million people have CKD. In Japan, major causes of end-stage kidney disease are type 2 diabetic nephropathy, chronic glomerulonephritis, especially IgA nephropathy, hypertensive nephrosclerosis, and polycystic kidney disease. IgA nephropathy is characterized by polymeric IgA1 with aberrant galactosylation (galactose-deficient IgA1) increased in the blood and deposited in the glomerular mesangial areas, as well as partially in the capillary walls. The tonsils are important as one of the responsible regions in this disease. The clarification of the mechanism of galactose-deficient IgA1 production will pave the way for the development of novel therapies. The results of future research are eagerly awaited. At present, the most important therapeutic goals in patients with IgA nephropathy are the control of hypertension, the decrease of urinary protein excretion, and the inhibition of progression to end-stage kidney disease. Several investigators have reported that renin-angiotensin-aldosterone system inhibitors reduce levels of urinary protein excretion and preserve renal function in patients with IgA nephropathy. In Japan, tonsillectomy and steroid pulse therapy are more effective for patients with IgA nephropathy.
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Affiliation(s)
- Yasuhiko Tomino
- Juntendo University, Tokyo, Japan; Medical Corporation SHOWAKAI, Tokyo, Japan
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Vibration Induces BAFF Overexpression and Aberrant O-Glycosylation of IgA1 in Cultured Human Tonsillar Mononuclear Cells in IgA Nephropathy. BIOMED RESEARCH INTERNATIONAL 2016; 2016:9125960. [PMID: 27672662 PMCID: PMC5031824 DOI: 10.1155/2016/9125960] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 07/09/2016] [Accepted: 07/19/2016] [Indexed: 11/23/2022]
Abstract
Objective. To investigate the influence of in vitro vibratory stimulation of human tonsillar mononuclear cells (TMCs). Methods. Fourteen IgA nephropathy (IgAN) patients with chronic tonsillitis (CT) and 12 CT patients with no renal pathology were enrolled. Group A TMCs were collected after 24 hours of culture and used to determine baseline levels. TMCs in groups B, C, D, E, and F were exposed to vibratory stimulation (60 Hz) for 0 (as the control group), 1, 3, 5, and 10 minutes, respectively. Results. Baseline concentrations of B-cell-activation factor (BAFF) and IgA1, BAFF mRNA expression, and aberrant O-glycosylation IgA1 level were higher in the IgAN group as compared to that in the CT group, and all increased after vibratory stimulation. Baseline mRNA expressions of core β1,3-galactosyltransferase (C1GALT1) and core β1,3GalT-specific molecular chaperone (Cosmc) were lower in the IgAN group; the levels decreased further after vibratory stimulation. Conclusion. In patients with IgAN, vibratory stimulation of TMCs appears to induce IgA1 secretion through activation of BAFF release and to aberrant O-glycosylation IgA1 by suppressing C1GALT1 and Cosmc expression. In vitro vibratory stimulation of human TMCs mimics the vibratory simulation of palatine tonsils produced by vocal cords during phonation.
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Shen P, Shen J, Sun C, Yang X, He L. A system biology approach to understanding the molecular mechanisms of Gubentongluo decoction acting on IgA Nephropathy. Altern Ther Health Med 2016; 16:312. [PMID: 27558012 PMCID: PMC4997663 DOI: 10.1186/s12906-016-1268-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 08/02/2016] [Indexed: 11/16/2022]
Abstract
Background Traditional Chinese medicine (TCM) has been widely used in treating various diseases in eastern Asia for several thousand years, and is becoming increasingly popular in western countries. Gubentongluo (GBTL) decoction, as a classic TCM formula, is commonly applied to treat IgA Nephropathy (IgAN) in China. To date, however, the pharmacological/molecular mechanisms of GBTL have not been fully elucidated. Method In the present study, we used a system biological approach to explore these mechanisms acting on IgAN. Results First, we found 3876 potential target proteins for GBTL (based on TCMID) and 25 known IgAN associated biomarkers (based on the OMIM or IPA database).16 of the latter biomarkers were direct targets of 6 of the 9 herbs in GBTL, suggesting that these components play a vital role in treating IgAN. Second, we showed that these 6 herbs mainly regulate the immune system and renin-angiotensin system, imbalance in which is the main factor leading to IgAN. Importantly, HUANG QI links with 14 biomarkers, indicating that it is the most important herb in GBTL for treating IgAN. Also, relationships of other herbs with IgAN were explored. Third, we demonstrated that the remaining 9 IgAN associated proteins are responses to biological processes, such as antigen processing, protein ubiquitination and cell cycle regulation, which are crucial for IgAN development. Finally, we found that GBTL could induce a significant increase in the levels of two target gene: TNF and NOS2. Conclusions Further studies are called to develop/modify the formula of GBTL, in order to enhance its effect on IgAN. Electronic supplementary material The online version of this article (doi:10.1186/s12906-016-1268-9) contains supplementary material, which is available to authorized users.
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Xie YX, He LY, Chen X, Peng XF, Ye MY, Zhao YJ, Yan WZ, Liu C, Shao J, Peng YM. Potential diagnostic biomarkers for IgA nephropathy: a comparative study pre- and post-tonsillectomy. Int Urol Nephrol 2016; 48:1855-1861. [PMID: 27465795 DOI: 10.1007/s11255-016-1372-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 07/11/2016] [Indexed: 01/08/2023]
Abstract
OBJECTIVE The proteins BAFF, ST6GALNAC2, C1GALT1, and COSMC in peripheral blood mononuclear cells (PBMCs) and plasma levels of IgA1 and galactose-deficient IgA1 (Gd-IgA1) are potential biomarkers for IgAN nephropathy. In this study, we comparatively studied the changes of those biomarkers before and after tonsillectomy. METHODS Peripheral blood samples were obtained from 16 IgAN patients with pre- and post-tonsillectomy. IgAN was diagnosed based on results from analysis of percutaneous renal biopsy tissue. Peripheral blood samples from three patients without renal diseases (non-IgAN), before and after tonsillectomy, and 16 healthy controls were also examined. BAFF, ST6GALNAC2, C1GALT1, and COSMC mRNA levels in PBMCs were detected using real-time PCR. Plasma IgA1 content was measured by ELISA. Gd-IgA1 levels were determined using the VV lectin-ELISA method. RESULTS BAFF, ST6GALNAC2, C1GALT1, and COSMC mRNA levels and the plasma concentrations of IgA1 and Gd-IgA1 in IgAN patients before tonsillectomy were significantly higher than those in healthy controls (P < 0.05). Tonsillectomy significantly increased the expression of BAFF and ST6GALNAC2, and plasma IgA1 level, while it downregulated that of C1GALT1 and COSMC (P < 0.05). However, in non-IgAN patients, tonsillectomy did not affect the mRNA levels of BAFF, ST6GALNAC2, C1GALT1, and COSMC, plasma IgA1 content and Gd-IgA1 level. Positive correlations were established between BAFF and IgA1 (r = 0.604, P < 0.01) and between ST6GALNAC2 and Gd-IgA1 (r = 0.623, P < 0.01). CONCLUSIONS Tonsillectomy changes the mRNA levels of BAFF, ST6GALNAC2, C1GALT1, and COSMC in PBMCs, as well as the plasma IgA1 level in IgAN patients. BAFF and ST6GALNAC2 might regulate IgA1 secretion and O-glycosylation.
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Affiliation(s)
- Ying-Xin Xie
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China.,Nephrology Department, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Li-Yu He
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China
| | - Xian Chen
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China
| | - Xiao-Fei Peng
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China
| | - Mu-Yao Ye
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China
| | - Yu-Jing Zhao
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China
| | - Wen-Zhe Yan
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China
| | - Chan Liu
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China
| | - Jing Shao
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China
| | - You-Ming Peng
- Nephrology Department, 2nd Xiangya Hospital, Central South University, Key Lab of Kidney Disease and Blood Purification in Hunan, 139 Renmin Road, Changsha, 410011, Hunan, People's Republic of China.
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