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Progress in research into the role of abnormal glycosylation modification in tumor immunity. Immunol Lett 2020; 229:8-17. [PMID: 33186635 DOI: 10.1016/j.imlet.2020.11.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/25/2020] [Accepted: 11/07/2020] [Indexed: 12/22/2022]
Abstract
In abnormal glycosylation, molecules of glucose or other carbohydrates in living organisms are inappropriately attached to proteins, which causes protein denaturation. Abnormal glycosylation modification is known to directly or indirectly affect the tumor escape process, but very few studies have been performed on whether protein glycosylation changes the structure and function of immune cells and immune molecules and thereby regulates the occurrence and development of tumor escape. Therefore, this article summarizes the effect of the immune system on tumor escape in association with the abnormal glycosylation process from an immunological perspective.
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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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53
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Gan T, Li Y, Zhou XJ, Zhang H. Immunoproteasome in IgA Nephropathy: State-of-Art and Future Perspectives. Int J Biol Sci 2020; 16:2518-2526. [PMID: 32792854 PMCID: PMC7415421 DOI: 10.7150/ijbs.48330] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 07/10/2020] [Indexed: 12/14/2022] Open
Abstract
IgA nephropathy (IgAN) is a leading cause of chronic kidney disease and renal failure. The exact pathogenesis of IgAN is not well defined, but some genetic studies have led to a novel discovery that the immunoproteasome probably plays an important role in IgAN. The immunoproteasome is a proteasome variant that is expressed when cells are stressed or receive inflammatory signals. While immunoproteasome is suggested to be mainly involved in major histocompatibility complex-I (MHC-I) antigen presentation, recent studies indicate that it may assert broad functions in trafficking events that activate both innate and adaptive immunity. In this review, we first summarize new insights into its functions in immunity, and discuss how it underlies its associations with IgAN. We also highlight its potential as a therapeutic target for the future.
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Affiliation(s)
- Ting Gan
- Renal Division, Peking University First Hospital; Peking University Institute of Nephrology; Key Laboratory of Renal Disease, Ministry of Health of China; Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, 100034, People's Republic of China; Research Units of Diagnosis and Treatment of Immune-mediated Kidney Diseases, Chinese Academy of Medical Sciences
| | - Yang Li
- Renal Division, Peking University First Hospital; Peking University Institute of Nephrology; Key Laboratory of Renal Disease, Ministry of Health of China; Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, 100034, People's Republic of China; Research Units of Diagnosis and Treatment of Immune-mediated Kidney Diseases, Chinese Academy of Medical Sciences
| | - Xu-Jie Zhou
- Renal Division, Peking University First Hospital; Peking University Institute of Nephrology; Key Laboratory of Renal Disease, Ministry of Health of China; Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, 100034, People's Republic of China; Research Units of Diagnosis and Treatment of Immune-mediated Kidney Diseases, Chinese Academy of Medical Sciences
| | - Hong Zhang
- Renal Division, Peking University First Hospital; Peking University Institute of Nephrology; Key Laboratory of Renal Disease, Ministry of Health of China; Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, 100034, People's Republic of China; Research Units of Diagnosis and Treatment of Immune-mediated Kidney Diseases, Chinese Academy of Medical Sciences
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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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Yang X, Zhu A, Meng H. Tonsillar immunology in IgA nephropathy. Pathol Res Pract 2020; 216:153007. [PMID: 32534712 DOI: 10.1016/j.prp.2020.153007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 04/12/2020] [Accepted: 05/10/2020] [Indexed: 02/07/2023]
Abstract
As one of the most common types of primary glomerulonephritis, IgA nephropathy (IgAN) is often characterized by the immunoprecipitation of IgA1 in mesangial area. In clinical terms, IgA nephropathy can be treated with tonsillectomy or conservative treatment, basing on modern immunology knowledge in which the mucosa immune system (MIS), especially the widely distributed mucosa-associated lymphoid tissue (MALT) is focused accordingly In terms of basic research, IgAN has been shown correlated with multiple factors, including serum Gd-IgA1 level, IgA-IgG immunity, tonsil-associated bacteria,GADD34, CX3CR1, FOXP3 and the expression of other related intrinsic immune antibody. Therefore, it is reasonable there could be mutual correlation among IgAN-associated factors. The purpose of this study is to review the new progress on the treatment and prevention of IgAN diseases and related mechanisms of IgAN tonsils, which will be of great significance for the therapy of IgAN patients.
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Affiliation(s)
- Xinxin Yang
- Department of Pathology, Harbin Medical University Cancer Hospital, Harbin, China
| | - Anchao Zhu
- Department of Pathology, Harbin Medical University Cancer Hospital, Harbin, China
| | - Hongxue Meng
- Department of Pathology, Harbin Medical University Cancer Hospital, Harbin, China.
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56
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王 彬, 邵宽 芙, 董 晨. [Expression and significance of follicular helper T cells and galactose-deficient IgA1 in children with Henoch-Schönlein purpura]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2020; 22:473-477. [PMID: 32434643 PMCID: PMC7389409 DOI: 10.7499/j.issn.1008-8830.1911029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/09/2020] [Indexed: 05/31/2023]
Abstract
OBJECTIVE To study the role of follicular helper T (Tfh) cells and galactose-deficient IgA1 (Gd-IgA1) in the pathogenesis of childhood Henoch-Schönlein purpura (HSP) and the correlation between them. METHODS A total of 36 children with newly-diagnosed HSP were enrolled. They were divided into two groups: HSP nephritis (HSPN) group with 11 children and non-HSPN group with 25 children according to the presence or absence of HSPN. Another 15 children who underwent physical examination at the outpatient service were enrolled as the healthy control group. Flow cytometry was used to measure the proportion of Tfh cells (CD4+CXCR5+ICOS+) in peripheral blood. ELISA was used to measure the levels of interleukin-21 (IL-21) and interleukin-6 (IL-6) in peripheral blood and the serum levels of IgA1 and Gd-IgA1. A Pearson correlation analysis was used to investigate the correlation of serum Gd-IgA1 concentration with Tfh cells and related factors expression in the children with HSP. RESULTS Both the HSPN and non-HSPN groups had significantly higher proportion of Tfh cells and expression levels of IL-21 and IL-6 in peripheral blood than the healthy control group (P<0.05). The HSPN group had significant increases in the above indices compared with the non-HSPN group (P<0.05). Both the HSPN and non-HSPN groups had significantly higher serum levels of IgA1 and Gd-IgA1 than the healthy control group (P<0.05). The HSPN group had significantly higher serum levels of IgA1 and Gd-IgA1 than the non-HSPN group (P<0.05). In the children with HSP, serum Gd-IgA1 level was positively correlated with Tfh cells proportion and IL-21 and IL-6 levels (P<0.05). CONCLUSIONS Tfh cells and related cytokines and serum Gd-IgA1 are involved in the development of HSP/HSPN. Tfh cells may mediate the increased production of Gd-IgA1.
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Affiliation(s)
- 彬 王
- />徐州医科大学附属医院儿科, 江苏 徐州 221000Department of Pediatrics, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221000, China
| | - 芙蓉 邵宽
- />徐州医科大学附属医院儿科, 江苏 徐州 221000Department of Pediatrics, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221000, China
| | - 晨 董
- />徐州医科大学附属医院儿科, 江苏 徐州 221000Department of Pediatrics, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221000, China
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57
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王 彬, 邵宽 芙, 董 晨. [Expression and significance of follicular helper T cells and galactose-deficient IgA1 in children with Henoch-Schönlein purpura]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2020; 22:473-477. [PMID: 32434643 PMCID: PMC7389409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/09/2020] [Indexed: 08/01/2024]
Abstract
OBJECTIVE To study the role of follicular helper T (Tfh) cells and galactose-deficient IgA1 (Gd-IgA1) in the pathogenesis of childhood Henoch-Schönlein purpura (HSP) and the correlation between them. METHODS A total of 36 children with newly-diagnosed HSP were enrolled. They were divided into two groups: HSP nephritis (HSPN) group with 11 children and non-HSPN group with 25 children according to the presence or absence of HSPN. Another 15 children who underwent physical examination at the outpatient service were enrolled as the healthy control group. Flow cytometry was used to measure the proportion of Tfh cells (CD4+CXCR5+ICOS+) in peripheral blood. ELISA was used to measure the levels of interleukin-21 (IL-21) and interleukin-6 (IL-6) in peripheral blood and the serum levels of IgA1 and Gd-IgA1. A Pearson correlation analysis was used to investigate the correlation of serum Gd-IgA1 concentration with Tfh cells and related factors expression in the children with HSP. RESULTS Both the HSPN and non-HSPN groups had significantly higher proportion of Tfh cells and expression levels of IL-21 and IL-6 in peripheral blood than the healthy control group (P<0.05). The HSPN group had significant increases in the above indices compared with the non-HSPN group (P<0.05). Both the HSPN and non-HSPN groups had significantly higher serum levels of IgA1 and Gd-IgA1 than the healthy control group (P<0.05). The HSPN group had significantly higher serum levels of IgA1 and Gd-IgA1 than the non-HSPN group (P<0.05). In the children with HSP, serum Gd-IgA1 level was positively correlated with Tfh cells proportion and IL-21 and IL-6 levels (P<0.05). CONCLUSIONS Tfh cells and related cytokines and serum Gd-IgA1 are involved in the development of HSP/HSPN. Tfh cells may mediate the increased production of Gd-IgA1.
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Affiliation(s)
- 彬 王
- />徐州医科大学附属医院儿科, 江苏 徐州 221000Department of Pediatrics, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221000, China
| | - 芙蓉 邵宽
- />徐州医科大学附属医院儿科, 江苏 徐州 221000Department of Pediatrics, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221000, China
| | - 晨 董
- />徐州医科大学附属医院儿科, 江苏 徐州 221000Department of Pediatrics, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221000, China
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58
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Sugiyama M, Wada Y, Kanazawa N, Tachibana S, Suzuki T, Matsumoto K, Iyoda M, Honda H, Shibata T. A cross-sectional analysis of clinicopathologic similarities and differences between Henoch-Schönlein purpura nephritis and IgA nephropathy. PLoS One 2020; 15:e0232194. [PMID: 32324811 PMCID: PMC7179927 DOI: 10.1371/journal.pone.0232194] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 04/08/2020] [Indexed: 12/17/2022] Open
Abstract
Introduction Recent studies noted that Henoch-Schönlein purpura nephritis (HSPN) and IgA nephropathy (IgAN) share the feature of galactose-deficient IgA1 (Gd-IgA1)-oriented pathogenesis, although there are distinct clinical differences. We aimed to clarify the clinicopathologic differences between these 2 diseases. Methods We cross-sectionally analyzed adult patients with HSPN (n = 24) or IgAN (n = 56) who underwent renal biopsy (RB) between 2008 and 2018 at Showa University Hospital. Serum Gd-IgA1 (s-Gd-IgA1) levels at the time of RB were compared among study groups using enzyme-linked immunosorbent assay (ELISA) with anti-human Gd-IgA1-specific monoclonal antibody (KM55). We also immunohistochemically stained paraffin-embedded sections for glomerular Gd-IgA1 (g-Gd-IgA1)-deposition using KM55. Serum inflammatory cytokines were measured using ELISA. Results Glomerular endothelial injury with subendothelial IgA deposition was significant in patients with HSPN. Serum IL-8, MCP-1, TNF-α, and IL-6 levels were significantly higher in patients with HSPN than IgAN. Levels of s-Gd-IgA1 were comparable among patients with HSPN and IgAN, and a similar degree of g-Gd-IgA1-deposition was detected in both diseases. Furthermore, g-Gd-IgA1-deposition was evident in patients with histopathologically advanced HSPN or IgAN. In HSPN, significant positive correlations between s-Gd-IgA1 levels and crescent formation or IL-6 elevation were confirmed, and g-Gd-IgA1 intensity showed a significant positive correlation with MCP-1 and a tendency to positively correlate with IL-8. Meanwhile, patients with IgAN showed no correlation between inflammatory cytokines and both-Gd-IgA1. Moreover, most g-Gd-IgA1-positive areas were not double stained with CD31 in HSPN. Conclusions Although assessing both-Gd-IgA1 alone was insufficient to distinguish between HSPN and IgAN, patients with HSPN showed considerable glomerular capillaritis with subendothelial IgA deposition and significant elevation of serum inflammatory cytokines. Furthermore, such glomerular subendothelial IgA deposition might not contain Gd-IgA1, and factors associated with Gd-IgA1 were inconsistent among these 2 diseases. Thus, developmental mechanisms for IgAN might not apply to HSPN completely, and these 2 diseases still have different aspects.
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Affiliation(s)
- Motonori Sugiyama
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Yukihiro Wada
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
- * E-mail:
| | - 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
| | - Taihei Suzuki
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Kei Matsumoto
- 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
| | - Hirokazu Honda
- 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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Yamada K, Huang ZQ, Raska M, Reily C, Anderson JC, Suzuki H, Kiryluk K, Gharavi AG, Julian BA, Willey CD, Novak J. Leukemia Inhibitory Factor Signaling Enhances Production of Galactose-Deficient IgA1 in IgA Nephropathy. KIDNEY DISEASES 2020; 6:168-180. [PMID: 32523959 DOI: 10.1159/000505748] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 12/23/2019] [Indexed: 12/13/2022]
Abstract
Objectives IgA nephropathy (IgAN) is thought to involve an autoimmune process wherein galactose-deficient IgA1 (Gd-IgA1), recognized as autoantigen by autoantibodies, forms pathogenic immune complexes. Mounting evidence has implicated abnormal activation of some protein-tyrosine kinases (PTKs) in IgAN. Furthermore, genome-wide association studies (GWAS) of IgAN provided insight into disease pathobiology and genetics. A GWAS locus on chromosome 22q12 contains genes encoding leukemia inhibitory factor (LIF) and oncostatin M, interleukin (IL)-6-related cytokines implicated in mucosal immunity and inflammation. We have previously shown that IL-6 mediates overproduction of Gd-IgA1 through aberrant STAT3 activation. Here, we show that LIF enhanced production of Gd-IgA1 in IgA1-secreting cells of patients with IgAN and provide initial analyses of LIF signaling. Methods We characterized LIF signaling that is involved in the overproduction of Gd-IgA1, using IgA1-secreting cell lines derived from peripheral blood of patients with IgAN and healthy controls (HC). We used global PTK activity profiling, immunoblotting, lectin ELISA, and siRNA knock-down. Results LIF stimulation did not significantly affect production of total IgA1 in IgA1-secreting cells from patients with IgAN or HC. However, LIF increased production of Gd-IgA1, but only in the cells from patients with IgAN. LIF stimulation enhanced phosphorylation of STAT1 in IgA1-secreting cells from patients with IgAN to a higher degree than in the cells from HC. siRNA knock-down of STAT1 blocked LIF-mediated overproduction of Gd-IgA1. Unexpectedly, this abnormal phosphorylation of STAT1 in IgA1-secreting cells from patients with IgAN was not mediated by JAK, but rather involved activation of Src-family PTKs (SFKs). Conclusion Abnormal LIF/STAT1 signaling represents another pathway potentially leading to overproduction of Gd-IgA1 in IgAN, providing possible explanation for the phenotype associated with chromosome 22q12 GWAS locus. Abnormal LIF/STAT1 signaling and the associated SFKs may represent potential diagnostic and/or therapeutic targets in IgAN.
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Affiliation(s)
- Koshi Yamada
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Zhi Qiang Huang
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Milan Raska
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Department of Immunology, Palacky University Olomouc, Olomouc, Czechia
| | - Colin Reily
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Joshua C Anderson
- Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Hitoshi Suzuki
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Krzysztof Kiryluk
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Ali G Gharavi
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Bruce A Julian
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Christopher D Willey
- Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
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Liu D, Xia M, Liu Y, Tan X, He L, Liu Y, Chen G, Liu H. The upregulation of miR-98-5p affects the glycosylation of IgA1 through cytokines in IgA nephropathy. Int Immunopharmacol 2020; 82:106362. [PMID: 32126510 DOI: 10.1016/j.intimp.2020.106362] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 02/26/2020] [Accepted: 02/27/2020] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Increases in galactose-deficient IgA1 (Gd-IgA1) play a crucial role in the pathogenesis of IgA nephropathy (IgAN), and several recent experiments have shown that microRNAs (miRNAs) are involved in regulating the development and physiological function of the kidney. The aims of this study were to identify miRNAs that can affect the pathogenesis of IgAN and reveal the underlying regulatory mechanism of IgA1 glycosylation in peripheral blood. METHODS The differentially expressed miRNAs in peripheral blood mononuclear cells (PBMCs) between IgAN patients and healthy controls were screened by high-throughput sequencing, and the targets of these miRNAs were predicted and verified by dual-luciferase reporter assays. We also explored the miRNA regulation of Gd-IgA1 through the transfection of miRNA mimics and related plasmids. RESULTS The high-throughput sequencing results showed that miR-98-5p was more highly expressed in the PBMCs of IgAN patients compared with healthy controls, and the luciferase reporter gene system confirmed that miR-98-5p might target chemokine ligand 3 (CCL3). The transfection of si-CCL3 confirmed that a decrease in CCL3 can affect the expression of interleukin-6 (IL-6) and C1GALT1. The overexpression of miR-98-5p in PBMCs through the transfection of miR-98-5p mimic reduced the CCL3 and C1GALT1 levels and increased the IL-6 levels, and these changes in PBMCs were attenuated by cotransfection with the CCL3 plasmid. CONCLUSION The results showed that in PBMCs, miR-98-5p can target CCL3 to decrease its expression and thereby increase the IL-6 levels, and the resulting increase in IL-6 can decrease C1GALT1 expression. Therefore, miR-98-5p might be involved in the development of IgAN.
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Affiliation(s)
- Di Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, No. 139 Renmin Middle Road, Changsha 410011, Hunan, China
| | - Ming Xia
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, No. 139 Renmin Middle Road, Changsha 410011, Hunan, China
| | - Yexin Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, No. 139 Renmin Middle Road, Changsha 410011, Hunan, China
| | - Xia Tan
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, No. 139 Renmin Middle Road, Changsha 410011, Hunan, China
| | - Liyu He
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, No. 139 Renmin Middle Road, Changsha 410011, Hunan, China
| | - Yu Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, No. 139 Renmin Middle Road, Changsha 410011, Hunan, China
| | - Guochun Chen
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, No. 139 Renmin Middle Road, Changsha 410011, Hunan, China
| | - Hong Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, No. 139 Renmin Middle Road, Changsha 410011, Hunan, China.
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Crescentic IgA nephropathy after administration of human monoclonal interleukin-12/23p40 antibody in a patient with Crohn's disease: a case report. CEN Case Rep 2020; 9:204-209. [PMID: 32100251 DOI: 10.1007/s13730-020-00457-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Accepted: 02/13/2020] [Indexed: 10/24/2022] Open
Abstract
Ustekinumab (UST), an interleukin (IL)-12/IL-23-blocking monoclonal antibody, is a novel therapeutic option for Crohn's disease (CD). We describe a 24-year-old man with CD who showed an abrupt decline in renal function after administration of UST. Twenty-nine months previously, the patient was diagnosed with CD, and abnormal urinalysis findings in health checkup were coincidentally found at that time. Three months previously, treatment for CD was switched from infliximab to UST because of therapy-resistant severe diarrhea and bloody stools. A single dose of UST (260 mg) was initially intravenously administered, followed by single subcutaneous administration (90 mg) 2 months later. Thereafter, the patient exhibited rapid renal dysfunction with significant urinary abnormalities, although his gastrointestinal symptoms had completely disappeared. He was admitted to our hospital for further examination and treatment. Renal pathologic findings were compatible with crescentic glomerulonephritis consisting of almost fibro-cellular crescents. Immunofluorescent study showed IgA and C3 deposition in the glomerular mesangial area and IgA subclass staining revealed predominant IgA1 with concomitant mild IgA2 deposition. Furthermore, galactose-deficient IgA1 (Gd-IgA1) was also positive in the mesangial area. In addition, serum-Gd-IgA1 level was moderately increased. UST treatment was stopped and he responded to intensive steroid therapy with a parallel reduction of serum creatinine and Gd-IgA1 levels without flare of gastrointestinal symptoms. To our knowledge, this is the first case of immunoglobulin A nephropathy (IgAN) in patient with CD that might be aggravated by UST treatment. We presume that inhibition of IL-12/23 signaling with UST may cause to form crescentic IgAN by enhancing Gd-IgA1 production.
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Karasawa K, Ogura S, Miyabe Y, Akiyama K, Nitta K, Moriyama T. Case report on mesangial proliferative glomerulonephritis with multicentric Castleman's disease: Approach to the onset mechanism of immunoglobulin A nephropathy. Clin Immunol 2020; 212:108347. [PMID: 31978558 DOI: 10.1016/j.clim.2020.108347] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 01/20/2020] [Accepted: 01/20/2020] [Indexed: 10/25/2022]
Abstract
Galactose-deficient immunoglobulin A1 (Gd-IgA1) was recently identified as a critical effector molecule in the pathogenesis of IgA nephropathy (IgAN). Gd-IgA1 is produced by the mucosal immune system. IgAN is thought to develop because of the deposition of a circulating immune-complex containing Gd-IgA1 in the kidney. Multicentric Castleman's disease (MCD) is a rare non-neoplastic lymphoproliferative disorder. As an etiology model, hypercytokinemia, including increased levels of interleukin-6, is the primary pathogenesis of many MCD cases. Here, we present two cases of mesangial proliferative glomerulonephritis with MCD. According to renal biopsy findings, one was diagnosed with non-IgAN and the other with IgAN. Surprisingly, in both cases, Gd-IgA1 was produced by plasma cells in the lymph nodes, suggesting that Gd-IgA1 production alone does not cause IgAN; rather, it may be produced without induction by mucosal immunity. Our findings demonstrate the diversity of the development of IgAN and help to reconsider the onset mechanism of IgAN.
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Affiliation(s)
- Kazunori Karasawa
- Department of Nephrology, Tokyo Womens Medical University, Tokyo, Japan.
| | - Shota Ogura
- Department of Nephrology, Tokyo Womens Medical University, Tokyo, Japan
| | - Yoei Miyabe
- Department of Nephrology, Tokyo Womens Medical University, Tokyo, Japan
| | - Kenichi Akiyama
- Department of Nephrology, Tokyo Womens Medical University, Tokyo, Japan
| | - Kosaku Nitta
- Department of Nephrology, Tokyo Womens Medical University, Tokyo, Japan
| | - Takahito Moriyama
- Department of Nephrology, Tokyo Womens Medical University, Tokyo, Japan
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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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Perše M, Večerić-Haler Ž. The Role of IgA in the Pathogenesis of IgA Nephropathy. Int J Mol Sci 2019; 20:ijms20246199. [PMID: 31818032 PMCID: PMC6940854 DOI: 10.3390/ijms20246199] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/03/2019] [Accepted: 12/07/2019] [Indexed: 11/16/2022] Open
Abstract
Immunoglobulin A (IgA) is the most abundant antibody isotype produced in humans, predominantly present in the mucosal areas where its main functions are the neutralization of toxins, prevention of microbial invasion across the mucosal epithelial barrier, and simultaneous maintenance of a physiologically indispensable symbiotic relationship with commensal bacteria. The process of IgA biosynthesis, interaction with receptors, and clearance can be disrupted in certain pathologies, like IgA nephropathy, which is the most common form of glomerulonephritis worldwide. This review summarizes the latest findings in the complex characteristics of the molecular structure and biological functions of IgA antibodies, offering an in-depth overview of recent advances in the understanding of biochemical, immunologic, and genetic factors important in the pathogenesis of IgA nephropathy.
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Affiliation(s)
- Martina Perše
- Medical Experimental Centre, Institute of Pathology, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
- Correspondence: ; Tel.: +386-4047-4675
| | - Željka Večerić-Haler
- Department of Nephrology, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia;
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
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Zand L, Canetta P, Lafayette R, Aslam N, Jan N, Sethi S, Fervenza FC. An Open-Label Pilot Study of Adrenocorticotrophic Hormone in the Treatment of IgA Nephropathy at High Risk of Progression. Kidney Int Rep 2019; 5:58-65. [PMID: 31922061 PMCID: PMC6943772 DOI: 10.1016/j.ekir.2019.10.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 10/19/2019] [Accepted: 10/21/2019] [Indexed: 12/27/2022] Open
Abstract
Introduction IgA nephropathy (IgAN) is the most common glomerulonephritis with high risk of progression to end-stage renal disease in patients with proteinuria >1 g/24 hours. There are no known effective treatments in patients with IgAN. Methods We conducted a prospective open-label pilot study in patients with IgAN using adrenocorticotrophic hormone (ACTH) (Acthar Gel, Mallinckrodt Pharmaceuticals, Bedminster, NJ) at a dosage of 80 units subcutaneously twice weekly for a total of 6 months and followed patients for a total of 12 months. Patients had to have urinary protein >1 g/24 hours despite adequate renin-angiotensin-aldosterone system (RAAS) blockade and estimated glomerular filtration rate (eGFR) >30 ml/min at enrollment. Results A total of 19 patients were recruited and followed for 1 year. At baseline, the mean age was 34.9 ± 10.5 years with 11 men and 8 women, and 14 Caucasian and 5 Asian individuals. At 12 months, there was a statistically significant decline in 24-hour urinary protein from 2.6 to 1.3 g (P = 0.007) and significant increase in serum albumin (3.79 to 3.93, P = 0.02). There was no significant change in eGFR (65.5 to 61.1 ml/min, P = 0.1). There were 0 complete remissions and 8 partial remissions (42%). There were a total of 6 infections: 2 were viral and 4 required antibiotic therapy (2 sinusitis, 1 pneumonia, 1 otitis media). The most common adverse events included acne, hot flashes, soreness, and anxiety. Conclusion In summary, patients with IgAN with >1 g/24-hour urinary protein and eGFR >30 ml/min had a significant reduction in 24-hour urinary protein with stable eGFR at 12-month follow-up after being treated with 6 months of ACTH.
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Affiliation(s)
- Ladan Zand
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, USA
| | - Pietro Canetta
- Division of Nephrology and Hypertension, University of Columbia Medical Center, New York, New York, USA
| | - Richard Lafayette
- Division of Nephrology and Hypertension, Stanford University, Stanford, California, USA
| | - Nabeel Aslam
- Division of Nephrology and Hypertension, Mayo Clinic, Jacksonville, Florida, USA
| | - Novak Jan
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Sanjeev Sethi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Fernando C Fervenza
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, USA
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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: 82] [Impact Index Per Article: 16.4] [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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Autoantibodies Specific for Galactose-Deficient IgA1 in IgA Vasculitis With Nephritis. Kidney Int Rep 2019; 4:1717-1724. [PMID: 31844808 PMCID: PMC6895670 DOI: 10.1016/j.ekir.2019.08.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 08/11/2019] [Accepted: 08/19/2019] [Indexed: 12/30/2022] Open
Abstract
Introduction Patients with IgA nephropathy (IgAN) have elevated serum levels of galactose-deficient IgA1 (Gd-IgA1) that are bound by Gd-IgA1–specific autoantibodies in pathogenic immune complexes. Renal biopsy histopathologic features of IgA vasculitis (IgAV) with nephritis (IgAV-N) are similar to those of IgAN. Mucosal infections often are associated with clinical onset and exacerbation in both diseases. We investigated whether patients with IgAV-N share pathogenic characteristics of IgAN. Methods We generated IgA1- and IgG-secreting cell lines from Epstein-Barr virus (EBV)–immortalized cells of patients with IgAV without nephritis (IgAV-woN), IgAV-N, and IgAN and from healthy individuals. Sera and cell-culture supernatants were used for analysis of Gd-IgA1 and Gd-IgA1–specific IgG autoantibodies. Results IgA1-producing cells from patients with IgAV-N, like cells from patients with IgAN, secreted more Gd-IgA1 than did cells from patients with IgAV-woN or healthy control subjects, in agreement with elevated serum Gd-IgA1 levels in patients with IgAV-N and IgAN. IgA1-producing cells from patients with IgAV-N had altered expression of genes involved in O-glycan biosynthesis: decreased for core 1 synthase (glycoprotein-N-acetylgalactosamine 3-β-galactosyltransferase 1; C1GALT1) and C1GALT1 Specific Chaperone 1 (C1GALTC1; COSMC) and elevated for N-acetylgalactosaminide α-2,6-sialyltransferase 2 (ST6GALNAC2). Levels of Gd-IgA1–specific IgG in sera and supernatants of IgG-producing cells were similar for patients with IgAV-N and IgAN and higher than those for IgAV-woN patients or healthy control subjects. Moreover, patients with IgAV-N who had active disease, manifested by hematuria and substantial proteinuria, had higher serum levels of Gd-IgA1–specific IgG autoantibodies than did patients with IgAV-N who had inactive disease. Conclusion Serum levels and cellular production of Gd-IgA1 and Gd-IgA1–specific IgG autoantibodies were elevated in patients with IgAV-N, supporting the hypothesis that IgAV-N and IgAN share pathogenic features.
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Abstract
The glycome describes the complete repertoire of glycoconjugates composed of carbohydrate chains, or glycans, that are covalently linked to lipid or protein molecules. Glycoconjugates are formed through a process called glycosylation and can differ in their glycan sequences, the connections between them and their length. Glycoconjugate synthesis is a dynamic process that depends on the local milieu of enzymes, sugar precursors and organelle structures as well as the cell types involved and cellular signals. Studies of rare genetic disorders that affect glycosylation first highlighted the biological importance of the glycome, and technological advances have improved our understanding of its heterogeneity and complexity. Researchers can now routinely assess how the secreted and cell-surface glycomes reflect overall cellular status in health and disease. In fact, changes in glycosylation can modulate inflammatory responses, enable viral immune escape, promote cancer cell metastasis or regulate apoptosis; the composition of the glycome also affects kidney function in health and disease. New insights into the structure and function of the glycome can now be applied to therapy development and could improve our ability to fine-tune immunological responses and inflammation, optimize the performance of therapeutic antibodies and boost immune responses to cancer. These examples illustrate the potential of the emerging field of 'glycomedicine'.
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Affiliation(s)
- Colin Reily
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Tyler J Stewart
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
- National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - Matthew B Renfrow
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA.
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Neufeld M, Molyneux K, Pappelbaum KI, Mayer-Hain S, von Hodenberg C, Ehrchen J, Barratt J, Suzuki Y, Sunderkötter C. Galactose-deficient IgA1 in skin and serum from patients with skin-limited and systemic IgA vasculitis. J Am Acad Dermatol 2019; 81:1078-1085. [PMID: 30902725 DOI: 10.1016/j.jaad.2019.03.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 03/02/2019] [Accepted: 03/10/2019] [Indexed: 11/25/2022]
Abstract
BACKGROUND IgA vasculitis (IgAV) encompasses a systemic form involving kidneys, gut, skin, or joints, and a skin-limited form. One characteristic feature of systemic IgAV is deposition of galactose-deficient IgA1 (GD-IgA1) in kidneys (as in IgA nephropathy). The relevance of GD-IgA1 for cutaneous vasculitis is unknown. OBJECTIVE We investigated whether GD-IgA1 is deposited perivascularly in systemic and also skin-limited IgAV and whether its serum levels differ between both forms. METHODS In a case-control study, deposition of GD-IgA1 was analyzed immunohistochemically by KM55 antibody in skin biopsy specimens from 12 patients with skin-limited IgAV and 4 with systemic IgAV. GD-IgA1 levels were compared by enzyme-linked immunosorbent assay in sera from 15 patients each with skin-limited and systemic IgAV and from 11 healthy individuals. RESULTS All biopsy samples from systemic IgAV, and also from skin-limited IgAV, revealed perivascular GD-IgA1 deposition. The average GD-IgA1 concentration in serum was significantly higher in systemic IgAV than in skin-limited IgAV, despite overlap between the groups. LIMITATIONS Although high GD-IgA1 levels may be predictive of systemic IgAV, patient numbers were too low to determine cutoff values for systemic versus skin-limited IgAV. CONCLUSION Perivascular GD-IgA1 deposition is a prerequisite for systemic and skin-limited IgAV; however, high GD-IgA1 levels in some patients with systemic IgAV suggest a dose-dependent effect of GD-IgA1 in IgAV.
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Affiliation(s)
- Matthias Neufeld
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany; Department of Dermatology, University of Münster, Münster, Germany
| | - Karen Molyneux
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Karin I Pappelbaum
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany
| | - Sarah Mayer-Hain
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany
| | - Christina von Hodenberg
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany; Department of Dermatology, University of Münster, Münster, Germany
| | - Jan Ehrchen
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany; Department of Dermatology, University of Münster, Münster, Germany
| | - Jonathan Barratt
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Yusuke Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Cord Sunderkötter
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany; Department of Dermatology and Venereology, University Hospital of Halle, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany.
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Ruszkowski J, Lisowska KA, Pindel M, Heleniak Z, Dębska-Ślizień A, Witkowski JM. T cells in IgA nephropathy: role in pathogenesis, clinical significance and potential therapeutic target. Clin Exp Nephrol 2019; 23:291-303. [PMID: 30406499 PMCID: PMC6394565 DOI: 10.1007/s10157-018-1665-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/25/2018] [Indexed: 12/11/2022]
Abstract
BACKGROUND Immunoglobulin A nephropathy (IgAN), the most frequent cause of primary glomerulonephritis worldwide, is an autoimmune disease with complex pathogenesis. In this review, we focus on T cells and summarize knowledge about their involvement in pathophysiology and treatment of IgAN METHODS: We reviewed the literature for (1) alterations of T cell subpopulations in IgAN, (2) experimental and clinical proofs for T cells' participation in IgAN pathogenesis, (3) clinical correlations with T cell-associated alterations, and (4) influence of drugs used in IgAN therapy on T cell subpopulations. RESULTS We found that IgAN is characterized by higher proportions of circulatory Th2, Tfh, Th17, Th22 and γδ T cells, but lower Th1 and Treg cells. We discuss genetic and epigenetic makeup that may contribute to this immunological phenotype. We found that Th2, Th17 and Tfh-type interleukins contribute to elevated synthesis of galactose-deficient IgA1 (Gd-IgA1) and that the production of anti-Gd-IgA1 autoantibodies may be stimulated by Tfh cells. We described the roles of Th2, Th17, Th22 and Treg cells in the renal injury and summarized correlations between T cell-associated alterations and clinical features of IgAN (proteinuria, reduced GFR, hematuria). We detailed the impact of immunosuppressive drugs on T cell subpopulations and found that the majority of drugs have nonoptimal influence on T cells in IgAN patients. CONCLUSIONS T cells play an important role in IgAN pathogenesis and are correlated with its clinical severity. Clinical trials with the drugs targeting the reported alterations of the T-cell compartment are highly desirable.
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Affiliation(s)
- Jakub Ruszkowski
- Department of Pathophysiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 7, 80-211, Gdańsk, Poland.
| | - Katarzyna A Lisowska
- Department of Pathophysiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 7, 80-211, Gdańsk, Poland
| | - Małgorzata Pindel
- Department of Pathophysiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 7, 80-211, Gdańsk, Poland
| | - Zbigniew Heleniak
- Department of Nephrology, Transplantology and Internal Medicine, Faculty of Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Alicja Dębska-Ślizień
- Department of Nephrology, Transplantology and Internal Medicine, Faculty of Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Jacek M Witkowski
- Department of Pathophysiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 7, 80-211, Gdańsk, Poland
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Maixnerova D, Ling C, Hall S, Reily C, Brown R, Neprasova M, Suchanek M, Honsova E, Zima T, Novak J, Tesar V. Galactose-deficient IgA1 and the corresponding IgG autoantibodies predict IgA nephropathy progression. PLoS One 2019; 14:e0212254. [PMID: 30794576 PMCID: PMC6386256 DOI: 10.1371/journal.pone.0212254] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 01/29/2019] [Indexed: 01/07/2023] Open
Abstract
Background IgA nephropathy (IgAN), the most common primary glomerulonephritis worldwide, has serious outcomes with end-stage renal disease developing in 30–50% of patients. The diagnosis requires renal biopsy. Due to its inherent risks, non-invasive approaches are needed. Methods We evaluated 91 Czech patients with biopsy-proven IgAN who were assessed at time of diagnosis for estimated glomerular filtration rate (eGFR), proteinuria, microscopic hematuria, and hypertension, and then followed prospectively. Serum samples collected at diagnosis were analyzed for galactose-deficient IgA1 (Gd-IgA1) using new native-IgA1 and established neuraminidase-treated-IgA1 tests, Gd-IgA1-specific IgG autoantibodies, discriminant analysis and logistic regression model assessed correlations with renal function and Oxford classification (MEST score). Results Serum levels of native (P <0.005) and neuraminidase-treated (P <0.005) Gd-IgA1 were associated with the rate of eGFR decline. A higher relative degree of galactose deficiency in native serum IgA1 predicted a faster eGFR decline and poor renal survival (P <0.005). However, Gd-IgA1 has not differentiated patients with low vs. high baseline eGFR. Furthermore, patients with high baseline eGFR that was maintained during follow-up were characterized by low serum levels of Gd-IgA1-specific IgG autoantibodies (P = 0.003). Conclusions Including levels of native and neuraminidase-treated Gd-IgA1 and Gd-IgA1-specific autoantibodies at diagnosis may aid in the prognostication of disease progression in Czech patients with IgAN. Future tests will assess utility of these biomarkers in larger patients cohorts from geographically distinct areas.
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Affiliation(s)
- Dita Maixnerova
- General Teaching Hospital, 1st Faculty of Medicine, Charles University, Department of Nephrology, Prague, Czech Republic
- * E-mail:
| | - Chunyan Ling
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- Longhua Hospital, Shanghai University of Traditional Medicine, Shanghai, China
| | - Stacy Hall
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Colin Reily
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Rhubell Brown
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Michaela Neprasova
- General Teaching Hospital, 1st Faculty of Medicine, Charles University, Department of Nephrology, Prague, Czech Republic
| | - Miloslav Suchanek
- Jan Evangelista Purkyne University in Ústí nad Labem, Faculty of Environment, Ústí nad Labem, Czech Republic
| | - Eva Honsova
- Institute of Clinical and Experimental Medicine, Department of Pathology, Prague, Czech Republic
| | - Tomas Zima
- General Teaching Hospital, 1 Faculty of Medicine, Charles University, Institute of Medical Biochemistry and Laboratory Diagnostics, Prague, Czech Republic
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Vladimir Tesar
- General Teaching Hospital, 1st Faculty of Medicine, Charles University, Department of Nephrology, Prague, Czech Republic
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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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73
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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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Saha MK, Julian BA, Novak J, Rizk DV. Secondary IgA nephropathy. Kidney Int 2018; 94:674-681. [PMID: 29804660 PMCID: PMC6981247 DOI: 10.1016/j.kint.2018.02.030] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 01/24/2018] [Accepted: 02/06/2018] [Indexed: 12/14/2022]
Abstract
IgA nephropathy is the most common primary glomerulonephritis worldwide. Its frequent coexistence with inflammatory, infectious, or malignant processes raises the possibility of a pathologic rather than coincidental association. Major strides have been made to elucidate the underlying pathophysiologic events that culminate in the development of primary IgA nephropathy. Whether secondary forms of the disease share common pathways triggered by underlying disorders or different mechanisms leading to similar pathologic findings remains to be determined. In this article we describe the most frequent etiologies for secondary IgA nephropathy and review the available literature for the pathophysiology.
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Affiliation(s)
- Manish K Saha
- Department of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA; Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Bruce A Julian
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA; Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Dana V Rizk
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.
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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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76
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Wu MY, Chen CS, Yiang GT, Cheng PW, Chen YL, Chiu HC, Liu KH, Lee WC, Li CJ. The Emerging Role of Pathogenesis of IgA Nephropathy. J Clin Med 2018; 7:jcm7080225. [PMID: 30127305 PMCID: PMC6112037 DOI: 10.3390/jcm7080225] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 08/12/2018] [Accepted: 08/16/2018] [Indexed: 12/20/2022] Open
Abstract
IgA nephropathy is an autoimmune disease induced by fthe ormation of galactose-deficient IgA1 and anti-glycans autoantibody. A multi-hit hypothesis was promoted to explain full expression of IgA nephropathy. The deposition of immune complex resulted in activation of the complement, increasing oxidative stress, promoting inflammatory cascade, and inducing cell apoptosis via mesangio-podocytic-tubular crosstalk. The interlinked signaling pathways of immune-complex-mediated inflammation can offer a novel target for therapeutic approaches. Treatments of IgA nephropathy are also summarized in our review article. In this article, we provide an overview of the recent basic and clinical studies in cell molecular regulation of IgAN for further treatment interventions.
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Affiliation(s)
- Meng-Yu Wu
- Department of Emergency Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 231, Taiwan.
- Department of Emergency Medicine, School of Medicine, Tzu Chi University, Hualien 970, Taiwan.
| | - Chien-Sheng Chen
- Department of Emergency Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 231, Taiwan.
- Department of Emergency Medicine, School of Medicine, Tzu Chi University, Hualien 970, Taiwan.
| | - Giou-Teng Yiang
- Department of Emergency Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 231, Taiwan.
- Department of Emergency Medicine, School of Medicine, Tzu Chi University, Hualien 970, Taiwan.
| | - Pei-Wen Cheng
- Yuh-Ing Junior College of Health Care & Management, Kaohsiung 807, Taiwan.
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan.
| | - Yu-Long Chen
- Department of Emergency Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 231, Taiwan.
- Department of Emergency Medicine, School of Medicine, Tzu Chi University, Hualien 970, Taiwan.
| | - Hsiao-Chen Chiu
- Department of Obstetrics and Gynecology, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 231, Taiwan.
- Department of Obstetrics and Gynecology, School of Medicine, Tzu Chi University, Hualien 970, Taiwan.
| | - Kuan-Hung Liu
- Division of Nephrology, Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine National Cheng Kung University, Tainan 704, Taiwan.
| | - Wen-Chin Lee
- Division of Nephrology, Department of Internal Medicine, Chang Bing Show Chwan Memorial Hospital, Changhua 505, Taiwan.
| | - Chia-Jung Li
- Research Assistant Center, Show Chwan Memorial Hospital, Changhua 500, Taiwan.
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77
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Reily C, Rizk DV, Julian BA, Novak J. Assay for galactose-deficient IgA1 enables mechanistic studies with primary cells from IgA nephropathy patients. Biotechniques 2018; 65:71-77. [PMID: 30091383 PMCID: PMC6152805 DOI: 10.2144/btn-2018-0042] [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: 04/09/2018] [Accepted: 06/19/2018] [Indexed: 11/23/2022] Open
Abstract
AIMS IgA nephropathy, the most common primary glomerulonephritis worldwide, is characterized by glomerular deposition of galactose-deficient IgA1 and elevated serum levels of this IgA1 glycoform. Current ELISA methods lack sensitivity to assess galactose deficiency using small amounts of IgA1, which limits studies in primary cells due to modest IgA1 production in isolated peripheral-blood lymphocytes. METHODS Lectin from Helix pomatia was conjugated to biotin or acridinium ester and used in ELISA to detect galactose deficiency of IgA1 using small amounts of IgA1. RESULTS Lectin conjugated to acridinium had an approximately a log-fold increased sensitivity compared with biotin-labeled lectin. CONCLUSIONS The new method of using lectin from Helix pomatia conjugated to acridinium increased assay sensitivity, allowing future mechanistic studies with cultured primary cells.
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Affiliation(s)
- Colin Reily
- University of Alabama at Birmingham, Department of Medicine, Birmingham, AL, USA
| | - Dana V Rizk
- University of Alabama at Birmingham, Department of Medicine, Birmingham, AL, USA
| | - Bruce A Julian
- University of Alabama at Birmingham, Department of Medicine, Birmingham, AL, USA
- University of Alabama at Birmingham, Department of Microbiology, Birmingham, AL, USA
| | - Jan Novak
- University of Alabama at Birmingham, Department of Microbiology, Birmingham, AL, USA
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Extracellular galectins as controllers of cytokines in hematological cancer. Blood 2018; 132:484-491. [PMID: 29875102 DOI: 10.1182/blood-2018-04-846014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 05/31/2018] [Indexed: 12/19/2022] Open
Abstract
Galectins and cytokines are both secreted proteins whose levels are prognosis factors for several cancers. Extracellular galectins bind to the glycans decorating glycoproteins and are overproduced in most cancers. Accumulative evidence shows that galectins regulate cytokines during cancer progression. Although galectins alter cytokine function by binding to the glycans decorating cytokines or their receptors, cytokines could also regulate galectin expression and function. This review revises these complex interactions and their clinical impact, particularly in hematological cancers.
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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: 71] [Impact Index Per Article: 11.8] [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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80
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Interleukin-6 is essential for glomerular immunoglobulin A deposition and the development of renal pathology in Cd37-deficient mice. Kidney Int 2018; 93:1356-1366. [PMID: 29551516 DOI: 10.1016/j.kint.2018.01.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 01/02/2018] [Accepted: 01/04/2018] [Indexed: 12/30/2022]
Abstract
Immunoglobulin A (IgA) nephropathy (IgAN), the most common glomerulonephritis worldwide, is characterized by IgA depositions in the kidney. Deficiency of CD37, a leukocyte-specific tetraspanin, leads to spontaneous development of renal pathology resembling IgAN. However, the underlying molecular mechanism has not been resolved. Here we found that CD37 expression on B cells of patients with IgAN was significantly decreased compared to B cells of healthy donors. Circulating interleukin (IL)-6 levels, but not tumor necrosis factor-α or IL-10, were elevated in Cd37-/- mice compared to wild-type mice after lipopolysaccharide treatment. Cd37-/- mice displayed increased glomerular neutrophil influx, immune complex deposition, and worse renal function. To evaluate the role of IL-6 in the pathogenesis of accelerated renal pathology in Cd37-/-mice, we generated Cd37xIl6 double-knockout mice. These double-knockout and Il6-/- mice displayed no glomerular IgA deposition and were protected from exacerbated renal failure following lipopolysaccharide treatment. Moreover, kidneys of Cd37-/- mice showed more mesangial proliferation, endothelial cell activation, podocyte activation, and segmental podocyte foot process effacement compared to the double-knockout mice, emphasizing that IL-6 mediates renal pathology in Cd37-/- mice. Thus, our study indicates that CD37 may protect against IgA nephropathy by inhibition of the IL-6 pathway.
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81
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Kosztyu P, Hill M, Jemelkova J, Czernekova L, Kafkova LR, Hruby M, Matousovic K, Vondrak K, Zadrazil J, Sterzl I, Mestecky J, Raska M. Glucocorticoids Reduce Aberrant O-Glycosylation of IgA1 in IgA Nephropathy Patients. Kidney Blood Press Res 2018. [PMID: 29529610 DOI: 10.1159/000487903] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS IgA nephropathy is associated with aberrant O-glycosylation of IgA1, which is recognized by autoantibodies leading to the formation of circulating immune complexes. Some of them, after deposition into kidney mesangium, trigger glomerular injury. In patients with active disease nonresponding to angiotensin-converting enzyme inhibitors or angiotensin II blockers, corticosteroids are recommended. METHODS The relationship between the corticosteroid therapy and serum levels of IgA, aberrantly O-glycosylated IgA1, IgA-containing immune complexes and their mesangioproliferative activity was analyzed in IgA nephropathy patients and disease and healthy controls. RESULTS Prednisone therapy significantly reduced proteinuria and levels of serum IgA, galactose-deficient IgA1, and IgA-IgG immune complexes in IgA nephropathy patients and thus reduced differences in all of the above parameters between IgAN patients and control groups. A moderate but not significant reduction of mesangioproliferative potential of IgA-IgG immune complexes and IgA sialylation was detected. CONCLUSION The prednisone therapy reduces overall aberrancy in IgA1 O-glycosylation in IgA nephropathy patients, but the measurement of IgA1 parameters does not allow us to predict the prednisone therapy outcome in individual patients.
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Affiliation(s)
- Petr Kosztyu
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University, Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - Martin Hill
- Department of Steroids and Proteohormones and Department of Clinical Immunology, Institute of Endocrinology, Prague, Czech Republic
| | - Jana Jemelkova
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University, Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - Lydie Czernekova
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University, Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - Leona Raskova Kafkova
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University, Olomouc and University Hospital Olomouc, Olomouc, Czech Republic
| | - Miroslav Hruby
- Department of Internal Medicine III Nephrology, Rheumatology and Endocrinology, Palacky University Olomouc, Olomouc, Czech Republic
| | - Karel Matousovic
- Department of Medicine, Second School of Medicine, Charles University, Prague and University Hospital Motol, Prague, Czech Republic
| | - Karel Vondrak
- Department of Pediatrics, Second School of Medicine, Charles University, Prague and University Hospital Motol, Prague, Czech Republic
| | - Josef Zadrazil
- Department of Internal Medicine III Nephrology, Rheumatology and Endocrinology, Palacky University Olomouc, Olomouc, Czech Republic
| | - Ivan Sterzl
- Department of Steroids and Proteohormones and Department of Clinical Immunology, Institute of Endocrinology, Prague, Czech Republic
| | - Jiri Mestecky
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Division of Immunology and Gnotobiology Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic.,Institute of Immunology and Microbiology, First School of Medicine, Charles University, Prague, Czech Republic
| | - Milan Raska
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University, Olomouc and University Hospital Olomouc, Olomouc, Czech Republic.,Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
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Yang YZ, Liu LJ, Shi SF, Wang JW, Chen YQ, Lv JC, Zhang H. Effects of Hydroxychloroquine on Proteinuria in Immunoglobulin A Nephropathy. Am J Nephrol 2018; 47:145-152. [PMID: 29502121 DOI: 10.1159/000487330] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 02/01/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND Hydroxychloroquine (HCQ) is a well-known immunomodulator that is useful as in the treatment for lupus because of its inhibitory effect on toll-like receptors and cytokines, which are speculated to play a role in the pathogenesis of Immunoglobulin A (IgA) nephropathy (IgAN). However, there was only one study that investigated the effect of HCQ on proteinuria in patients with IgAN. METHODS Ninety patients with IgAN who received HCQ in addition to optimized dosage of renin-angiotensin-aldosterone system inhibitors (RAASi) were recruited for this study, and 90 matched historical controls who received RAASi alone were selected from our registry by the propensity score matching method. Their clinical data were compared at baseline and during follow-up till the termination of HCQ or addition of immunosuppressive agents. RESULTS The median baseline proteinuria level of the 90 patients who received HCQ was comparable with the RAASi-alone group (1.5 [1.2, 2.1] vs. 1.5 [1.2, 1.9] g/day, p = 0.74). At 6 months post-study initiation, the median proteinuria level in the HCQ group was lower than that in the RAASi-alone group (0.8 [0.7, 1.2] vs. 1.2 [0.8, 1.8] g/day, p = 0.02). The percentage by which proteinuria was reduced in the HCQ group was significantly higher than that in the RAASi-alone group (-43% [-57, -12] vs. -19% [-46, 17], p = 0.01). No serious adverse effects were documented during treatment with HCQ. CONCLUSION The addition of HCQ to RAASi resulted in a significant and safe reduction in proteinuria in patients with IgAN.
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83
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Placzek WJ, Yanagawa H, Makita Y, Renfrow MB, Julian BA, Rizk DV, Suzuki Y, Novak J, Suzuki H. Serum galactose-deficient-IgA1 and IgG autoantibodies correlate in patients with IgA nephropathy. PLoS One 2018; 13:e0190967. [PMID: 29324897 PMCID: PMC5764330 DOI: 10.1371/journal.pone.0190967] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 12/22/2017] [Indexed: 01/03/2023] Open
Abstract
IgA nephropathy is an autoimmune disease characterized by IgA1-containing glomerular immune deposits. We previously proposed a multi-hit pathogenesis model in which patients with IgA nephropathy have elevated levels of circulatory IgA1 with some O-glycans deficient in galactose (Gd-IgA1, autoantigen). Gd-IgA1 is recognized by anti-glycan IgG and/or IgA autoantibodies, resulting in formation of pathogenic immune complexes. Some of these immune complexes deposit in the kidney, activate mesangial cells, and incite glomerular injury leading to clinical presentation of IgA nephropathy. Several studies have demonstrated that elevated circulatory levels of either Gd-IgA1 or the corresponding autoantibodies predict progressive loss of renal clearance function. In this study we assessed a possible association between serum levels of Gd-IgA1 and IgG or IgA autoantibodies specific for Gd-IgA1 in serum samples from 135 patients with biopsy-proven IgA nephropathy, 76 patients with other renal diseases, and 106 healthy controls. Our analyses revealed a correlation between the concentrations of the autoantigen and the corresponding IgG autoantibodies in sera of patients with IgA nephropathy, but not of disease or healthy controls. Moreover, our data suggest that IgG is the predominant isotype of Gd-IgA1-specific autoantibodies in IgA nephropathy. This work highlights the importance of both initial hits in the pathogenesis of IgA nephropathy.
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Affiliation(s)
- William J. Placzek
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- * E-mail:
| | - Hiroyuki Yanagawa
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yuko Makita
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Matthew B. Renfrow
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Bruce A. Julian
- Department of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Dana V. Rizk
- Department of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Yusuke Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Jan Novak
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Hitoshi Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
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84
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Suzuki H, Yasutake J, Makita Y, Tanbo Y, Yamasaki K, Sofue T, Kano T, Suzuki Y. IgA nephropathy and IgA vasculitis with nephritis have a shared feature involving galactose-deficient IgA1-oriented pathogenesis. Kidney Int 2018; 93:700-705. [PMID: 29329643 DOI: 10.1016/j.kint.2017.10.019] [Citation(s) in RCA: 130] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 09/26/2017] [Accepted: 10/05/2017] [Indexed: 01/12/2023]
Abstract
Galactose-deficient IgA1 has been proposed as an important effector molecule in IgA nephropathy (IgAN). We previously showed that the galactose-deficient IgA1-specific monoclonal antibody KM55 can detect circulating galactose-deficient IgA1 in patients with IgAN, enabling us to study the molecular roles of galactose-deficient IgA1. Herein, we further examined the pathophysiological significance of galactose-deficient IgA1 in glomerular deposits of patients with IgAN by immunohistochemistry using KM55. Immunostaining of galactose-deficient IgA1 with KM55 was performed in paraffin-embedded sections of renal biopsy specimens from 48 patients with IgAN and 49 patients with other renal diseases such as lupus nephritis, HCV-related nephropathy, IgA vasculitis with nephritis (IgA-VN), and membranous nephropathy. Glomerular galactose-deficient IgA1 was specifically detected in IgAN and IgA-VN but not in the other renal diseases. Galactose-deficient IgA1 was localized predominantly in the mesangial region as IgA deposition. However, galactose-deficient IgA1 was not detected in patients with lupus nephritis accompanied by glomerular IgA deposition. Thus, our study strongly suggests that IgAN and IgA-VN have a shared feature regarding galactose-deficient IgA1-oriented pathogenesis.
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Affiliation(s)
- Hitoshi Suzuki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Junichi Yasutake
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan; Nephrology Research Labs, Kyowa Hakko Kirin Co., Ltd., Tokyo, Japan
| | - Yuko Makita
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yuki Tanbo
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan; Nephrology Research Labs, Kyowa Hakko Kirin Co., Ltd., Tokyo, Japan
| | - Kohei Yamasaki
- Department of Nephrology, Juntendo University Faculty of Medicine, Tokyo, Japan; Nephrology Research Labs, Kyowa Hakko Kirin Co., Ltd., Tokyo, Japan
| | - Tadashi Sofue
- Division of Nephrology and Dialysis, Department of CardioRenal and Cerebrovascular Medicine, Faculty of Medicine, Kagawa University, Takamatsu, Japan
| | - Toshiki Kano
- 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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85
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Heineke MH, Ballering AV, Jamin A, Ben Mkaddem S, Monteiro RC, Van Egmond M. New insights in the pathogenesis of immunoglobulin A vasculitis (Henoch-Schönlein purpura). Autoimmun Rev 2017; 16:1246-1253. [PMID: 29037908 DOI: 10.1016/j.autrev.2017.10.009] [Citation(s) in RCA: 178] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 08/29/2017] [Indexed: 12/16/2022]
Abstract
Immunoglobulin A vasculitis (IgAV), also referred to as Henoch-Schönlein purpura, is the most common form of childhood vasculitis. The pathogenesis of IgAV is still largely unknown. The disease is characterized by IgA1-immune deposits, complement factors and neutrophil infiltration, which is accompanied with vascular inflammation. Incidence of IgAV is twice as high during fall and winter, suggesting an environmental trigger associated to climate. Symptoms can resolve without intervention, but some patients develop glomerulonephritis with features similar to IgA nephropathy that include hematuria, proteinuria and IgA deposition in the glomerulus. Ultimately, this can lead to end-stage renal disease. In IgA nephropathy immune complexes containing galactose-deficient (Gd-)IgA1 are found and thought to play a role in pathogenesis. Although Gd-IgA1 complexes are also present in patients with IgAV with nephritis, their role in IgAV is disputed. Alternatively, it has been proposed that in IgAV IgA1 antibodies are generated against endothelial cells. We anticipate that such IgA complexes can activate neutrophils via the IgA Fc receptor FcαRI (CD89), thereby inducing neutrophil migration and activation, which ultimately causes tissue damage in IgAV. In this Review, we discuss the putative role of IgA, IgA receptors, neutrophils and other factors such as infections, genetics and the complement system in the pathogenesis of IgA vasculitis.
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Affiliation(s)
- Marieke H Heineke
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, De Boelelaan 1109, 1081 HZ Amsterdam, The Netherlands; Amsterdam Infection & Immunity Institute, Amsterdam, The Netherlands
| | - Aranka V Ballering
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, De Boelelaan 1109, 1081 HZ Amsterdam, The Netherlands; Amsterdam Infection & Immunity Institute, Amsterdam, The Netherlands
| | - Agnès Jamin
- National French Institute of Health and Medical Research (INSERM) U1149, Centre de Recherche Sur l'Inflammation, 16 Rue Henri Huchard, Paris 75018, France; National French Center of Scientific Research (CNRS) ERL8252, Paris, France; Université Paris Diderot, Sorbonne Paris Cité, Faculté de Médecine, Site Xavier Bichat, 16 Rue Henri Huchard, Paris 75018, France; Laboratory of Inflamex Excellency, Faculty of Medicine, Xavier Bichat Site, Paris, France
| | - Sanae Ben Mkaddem
- National French Institute of Health and Medical Research (INSERM) U1149, Centre de Recherche Sur l'Inflammation, 16 Rue Henri Huchard, Paris 75018, France; National French Center of Scientific Research (CNRS) ERL8252, Paris, France; Université Paris Diderot, Sorbonne Paris Cité, Faculté de Médecine, Site Xavier Bichat, 16 Rue Henri Huchard, Paris 75018, France; Laboratory of Inflamex Excellency, Faculty of Medicine, Xavier Bichat Site, Paris, France
| | - Renato C Monteiro
- National French Institute of Health and Medical Research (INSERM) U1149, Centre de Recherche Sur l'Inflammation, 16 Rue Henri Huchard, Paris 75018, France; National French Center of Scientific Research (CNRS) ERL8252, Paris, France; Université Paris Diderot, Sorbonne Paris Cité, Faculté de Médecine, Site Xavier Bichat, 16 Rue Henri Huchard, Paris 75018, France; Laboratory of Inflamex Excellency, Faculty of Medicine, Xavier Bichat Site, Paris, France
| | - Marjolein Van Egmond
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, De Boelelaan 1109, 1081 HZ Amsterdam, The Netherlands; Amsterdam Infection & Immunity Institute, Amsterdam, The Netherlands; Department of Surgery, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands.
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86
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Yamada K, Huang ZQ, Raska M, Reily C, Anderson JC, Suzuki H, Ueda H, Moldoveanu Z, Kiryluk K, Suzuki Y, Wyatt RJ, Tomino Y, Gharavi AG, Weinmann A, Julian BA, Willey CD, Novak J. Inhibition of STAT3 Signaling Reduces IgA1 Autoantigen Production in IgA Nephropathy. Kidney Int Rep 2017; 2:1194-1207. [PMID: 29270528 PMCID: PMC5733772 DOI: 10.1016/j.ekir.2017.07.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 07/06/2017] [Indexed: 12/11/2022] Open
Abstract
Introduction IgA nephropathy is a chronic renal disease characterized by mesangial immunodeposits that contain autoantigen, which is aberrantly glycosylated IgA1 with some hinge-region O-glycans deficient in galactose. Macroscopic hematuria during an upper respiratory tract infection is common among patients with IgA nephropathy, which suggests a connection between inflammation and disease activity. Interleukin-6 (IL-6) is an inflammatory cytokine involved in IgA immune response. We previously showed that IL-6 selectively increases production of galactose-deficient IgA1 in IgA1-secreting cells from patients with IgA nephropathy. Methods We characterized IL-6 signaling pathways involved in the overproduction of galactose-deficient IgA1. To understand molecular mechanisms, IL-6 signaling was analyzed by kinomic activity profiling and Western blotting, followed by confirmation assays using siRNA knock-down and small-molecule inhibitors. Results STAT3 was differentially activated by IL-6 in IgA1-secreting cells from patients with IgA nephropathy compared with those from healthy control subjects. Specifically, IL-6 induced enhanced and prolonged phosphorylation of STAT3 in the cells from patients with IgA nephropathy, which resulted in overproduction of galactose-deficient IgA1. This IL-6−mediated overproduction of galactose-deficient IgA1 could be blocked by small molecule inhibitors of JAK/STAT signaling. Discussion Our results revealed that IL-6−induced aberrant activation of STAT3-mediated overproduction of galactose-deficient IgA1. STAT3 signaling pathway may thus represent a new target for disease-specific therapy of IgA nephropathy.
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Affiliation(s)
- Koshi Yamada
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Zhi-Qiang Huang
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Milan Raska
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University and University Hospital Olomouc, Olomouc, Czech Republic
| | - Colin Reily
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Joshua C. Anderson
- Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Hitoshi Suzuki
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Hiroyuki Ueda
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Zina Moldoveanu
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Krzysztof Kiryluk
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, USA
| | - Yusuke Suzuki
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Robert J. Wyatt
- Department of Pediatrics, University of Tennessee Health Center, Memphis, Tennessee, USA
| | - Yasuhiko Tomino
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, Tokyo, Japan
- Medical Corporation Showakai, Tokyo, Japan
| | - Ali G. Gharavi
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, USA
| | - Amy Weinmann
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Bruce A. Julian
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Christopher D. Willey
- Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
- Correspondence: Jan Novak, Department of Microbiology, University of Alabama at Birmingham, 845 19 Street South, BBRB 761A, Birmingham, Alabama 35294, USA.Department of MicrobiologyUniversity of Alabama at Birmingham845 19 Street South, BBRB 761ABirminghamAlabama35294USA
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87
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Hobbs SJ, Nolz JC. Regulation of T Cell Trafficking by Enzymatic Synthesis of O-Glycans. Front Immunol 2017; 8:600. [PMID: 28596771 PMCID: PMC5442166 DOI: 10.3389/fimmu.2017.00600] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 05/08/2017] [Indexed: 12/27/2022] Open
Abstract
Selectins constitute a family of oligosaccharide binding proteins that play critical roles in regulating the trafficking of leukocytes. In T cells, L-selectin (CD62L) controls the capacity for naive and memory T cells to actively survey peripheral lymph nodes, whereas P- and E-selectin capture activated T cells on inflamed vascular endothelium to initiate extravasation into non-lymphoid tissues. The capacity for T cells to interact with all of these selectins is dependent on the enzymatic synthesis of complex O-glycans, and thus, this protein modification plays an indispensable role in regulating the distribution and homing of both naive and previously activated T cells in vivo. In contrast to neutrophils, O-glycan synthesis is highly dynamic in T cell populations and is largely controlled by extracellular stimuli such as antigen recognition or signaling though cytokine receptors. Herein, we review the basic principles of enzymatic synthesis of complex O-glycans, discuss tools and reagents for studying this type of protein modification and highlight our current understanding of how O-glycan synthesis is regulated and subsequently impacts the trafficking potential of diverse T cell populations.
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Affiliation(s)
- Samuel J Hobbs
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, United States
| | - Jeffrey C Nolz
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, United States.,Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, OR, United States.,Department of Radiation Medicine, Oregon Health and Science University, Portland, OR, United States
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88
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Ramos-Martínez E, Lascurain R, Tenorio EP, Sánchez-González A, Chávez-Rueda K, Chávez-Sánchez L, Jara-Quezada LJ, Chávez-Sánchez R, Zenteno E, Blanco-Favela F. Differential Expression of O-Glycans in CD4(+) T Lymphocytes from Patients with Systemic Lupus Erythematosus. TOHOKU J EXP MED 2017; 240:79-89. [PMID: 27600584 DOI: 10.1620/tjem.240.79] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
T cells from patients with systemic lupus erythematosus (SLE) show a decreased activation threshold and increased apoptosis. These processes seem to be regulated by glycosylated molecules on the T cell surface. Here, we determined through flow cytometry the expression of mucin-type O-glycans on T helper cells in peripheral blood mononuclear cells (PBMC) from 23 SLE patients and its relation with disease activity. We used lectins specific for the disaccharide Gal-GalNAc, such as Amaranthus leucocarpus lectin (ALL), Artocarpus integrifolia lectin (jacalin) and Arachis hypogaea lectin (peanut agglutinin, PNA), as well as lectins for sialic acid such as Sambucus nigra agglutinin (SNA) and Maakia amurensis agglutinin (MAA). The results showed that ALL, but not jacalin or PNA, identified significant differences in O-glycan expression on T helper cells from active SLE patients (n = 10). Moreover, an inverse correlation was found between the frequency of T helper cells recognized by ALL and SLE Disease Activity Index (SLEDAI) score in SLE patients. In contrast, SNA and MAA lectins did not identify any differences between CD4(+) T cells from SLE patients. There was no difference in the recognition by ALL on activated T helper cells and T regulatory (Treg) cells. Our findings point out that activation of SLE disease diminishes the expression of O-glycans in T helper cells; ALL could be considered as a marker to determine activity of the disease.
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Affiliation(s)
- Edgar Ramos-Martínez
- Unidad de Investigación Médica en Inmunología, Hospital de Pediatría, Centro Médico Nacional "Siglo XXI", Instituto Mexicano del Seguro Social (IMSS)
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89
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Gale DP, Molyneux K, Wimbury D, Higgins P, Levine AP, Caplin B, Ferlin A, Yin P, Nelson CP, Stanescu H, Samani NJ, Kleta R, Yu X, Barratt J. Galactosylation of IgA1 Is Associated with Common Variation in C1GALT1. J Am Soc Nephrol 2017; 28:2158-2166. [PMID: 28209808 DOI: 10.1681/asn.2016091043] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/10/2017] [Indexed: 11/03/2022] Open
Abstract
IgA nephropathy (IgAN), an important cause of kidney failure, is characterized by glomerular IgA deposition and is associated with changes in O-glycosylation of the IgA1 molecule. Here, we sought to identify genetic factors contributing to levels of galactose-deficient IgA1 (Gd-IgA1) in white and Chinese populations. Gd-IgA1 levels were elevated in IgAN patients compared with ethnically matched healthy subjects and correlated with evidence of disease progression. White patients with IgAN exhibited significantly higher Gd-IgA1 levels than did Chinese patients. Among individuals without IgAN, Gd-IgA1 levels did not correlate with kidney function. Gd-IgA1 level heritability (h2), estimated by comparing midparental and offspring Gd-IgA1 levels, was 0.39. Genome-wide association analysis by linear regression identified alleles at a single locus spanning the C1GALT1 gene that strongly associated with Gd-IgA1 level (β=0.26; P=2.35×10-9). This association was replicated in a genome-wide association study of separate cohorts comprising 308 patients with membranous GN from the UK (P<1.00×10-6) and 622 controls with normal kidney function from the UK (P<1.00×10-10), and in a candidate gene study of 704 Chinese patients with IgAN (P<1.00×10-5). The same extended haplotype associated with elevated Gd-IgA1 levels in all cohorts studied. C1GALT1 encodes a galactosyltransferase enzyme that is important in O-galactosylation of glycoproteins. These findings demonstrate that common variation at C1GALT1 influences Gd-IgA1 level in the population, which independently associates with risk of progressive IgAN, and that the pathogenic importance of changes in IgA1 O-glycosylation may vary between white and Chinese patients with IgAN.
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Affiliation(s)
| | - Karen Molyneux
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - David Wimbury
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Patricia Higgins
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Adam P Levine
- Division of Medicine, University College London, London, United Kingdom
| | | | | | - Peiran Yin
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; and
| | - Christopher P Nelson
- Department of Cardiovascular Sciences, University of Leicester and National Institute for Health Research Leicester Cardiovascular Biomedical Research Unit, Leicester, United Kingdom
| | | | - Nilesh J Samani
- Department of Cardiovascular Sciences, University of Leicester and National Institute for Health Research Leicester Cardiovascular Biomedical Research Unit, Leicester, United Kingdom
| | | | - Xueqing Yu
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; and
| | - Jonathan Barratt
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
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90
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Zhang YM, Zhou XJ, Zhang H. What Genetics Tells Us About the Pathogenesis of IgA Nephropathy: The Role of Immune Factors and Infection. Kidney Int Rep 2017; 2:318-331. [PMID: 29142962 PMCID: PMC5678660 DOI: 10.1016/j.ekir.2017.02.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 02/07/2017] [Accepted: 02/08/2017] [Indexed: 02/04/2023] Open
Abstract
Immunoglobulin A nephropathy (IgAN) is the most common type of primary glomerulonephritis, which is characterized by IgA1-containing immune-deposits in the glomerular mesangium. The epidemiologic observations of familial clustering as well as ethnic and regional discrepancies indicate a genetic component to IgAN. Large, international, genome-wide association studies have identified several susceptibility genes and loci for IgAN, many of which have been implicated in immune regulation and are shared with other autoimmune diseases. Notably, increasing numbers of genes involved in mucosal immunity have been detected; such genes may impact the susceptibility and progression of IgAN through interaction with environmental stimuli (especially infection). Here, we discuss the innate and adaptive immune mechanisms that drive protective immunity against pathogens. Our goal is to provide a representative overview of the synergistic roles between genetic predisposition and infection in IgAN pathogenesis. We anticipate that these results will provide potential therapeutic agents and advances in precision medicine.
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Affiliation(s)
- Yue-Miao Zhang
- Renal Division, Peking University First Hospital, Beijing, China.,Peking University Institute of Nephrology, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment, Peking University, Ministry of Education, Beijing, China
| | - Xu-Jie Zhou
- Renal Division, Peking University First Hospital, Beijing, China.,Peking University Institute of Nephrology, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment, Peking University, Ministry of Education, Beijing, China
| | - Hong Zhang
- Renal Division, Peking University First Hospital, Beijing, China.,Peking University Institute of Nephrology, Beijing, China.,Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.,Key Laboratory of Chronic Kidney Disease Prevention and Treatment, Peking University, Ministry of Education, Beijing, China
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91
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GWAS for serum galactose-deficient IgA1 implicates critical genes of the O-glycosylation pathway. PLoS Genet 2017; 13:e1006609. [PMID: 28187132 PMCID: PMC5328405 DOI: 10.1371/journal.pgen.1006609] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 02/27/2017] [Accepted: 01/27/2017] [Indexed: 12/12/2022] Open
Abstract
Aberrant O-glycosylation of serum immunoglobulin A1 (IgA1) represents a heritable pathogenic defect in IgA nephropathy, the most common form of glomerulonephritis worldwide, but specific genetic factors involved in its determination are not known. We performed a quantitative GWAS for serum levels of galactose-deficient IgA1 (Gd-IgA1) in 2,633 subjects of European and East Asian ancestry and discovered two genome-wide significant loci, in C1GALT1 (rs13226913, P = 3.2 x 10−11) and C1GALT1C1 (rs5910940, P = 2.7 x 10−8). These genes encode molecular partners essential for enzymatic O-glycosylation of IgA1. We demonstrated that these two loci explain approximately 7% of variability in circulating Gd-IgA1 in Europeans, but only 2% in East Asians. Notably, the Gd-IgA1-increasing allele of rs13226913 is common in Europeans, but rare in East Asians. Moreover, rs13226913 represents a strong cis-eQTL for C1GALT1 that encodes the key enzyme responsible for the transfer of galactose to O-linked glycans on IgA1. By in vitro siRNA knock-down studies, we confirmed that mRNA levels of both C1GALT1 and C1GALT1C1 determine the rate of secretion of Gd-IgA1 in IgA1-producing cells. Our findings provide novel insights into the genetic regulation of O-glycosylation and are relevant not only to IgA nephropathy, but also to other complex traits associated with O-glycosylation defects, including inflammatory bowel disease, hematologic disease, and cancer. O-glycosylation is a common type of post-translational modification of proteins; specific abnormalities in the mechanism of O-glycosylation have been implicated in cancer, inflammatory and blood diseases. However, the molecular basis of abnormal O-glycosylation in these complex disorders is not known. We studied the genetic basis of defective O-glycosylation of serum immunoglobulin A1 (IgA1), that represents the key pathogenic defect in IgA nephropathy, the most common form of primary glomerulonephritis worldwide. We report our results of the first genome-wide association study for this trait using serum assays in 2,633 individuals of European and East-Asian ancestry. In our genome scan, we observed two significant signals with large effects, on chromosomes 7p21.3 and Xq24, jointly explaining about 7% of trait variability. These signals implicate two genes that encode molecular partners essential for enzymatic O-glycosylation of IgA1 and mucins, and represent potential new targets for therapy.
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92
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Xiao J, Wang M, Xiong D, Wang Y, Li Q, Zhou J, Chen Q. TGF-β1 mimics the effect of IL-4 on the glycosylation of IgA1 by downregulating core 1 β1, 3-galactosyltransferase and Cosmc. Mol Med Rep 2016; 15:969-974. [PMID: 28035353 DOI: 10.3892/mmr.2016.6084] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 11/22/2016] [Indexed: 11/06/2022] Open
Abstract
The aberrant glycosylation of IgA1 is pivotal in the pathogenesis of IgA nephropathy (IgAN). The aim of the present study was to investigate the effect of transforming growth factor‑β1 (TGF‑β1) on the glycosylation of IgA1 and the associated mechanism. The mRNA levels of core1 β1, 3-galactosyltransferase (C1GalT1) and its molecular chaperone, Cosmc, were analyzed, as was the subsequent O-glycosylation of IgA1, in a human B‑cell line stimulated with TGF‑β1. The IgA1‑positive human B‑cell line was cultured with different concentrations of recombinant human TGF‑β1 (5, 10, 15 and 30 ng/ml). The production and glycosylation of IgA1 were assayed using sandwich ELISA and enzyme‑linked lectin binding assays, respectively, and the mRNA levels of C1GalT1 and Cosmc were quantified using reverse transcription‑quantitative polymerase chain reaction analysis. The results showed that the production of IgA1 was stimulated by low concentrations of TGF‑β1 (5 or 10 ng/ml) and was suppressed by high concentrations (15 or 30 ng/ml). The terminal glycosylation of secreted IgA1 was altered in response to TGF‑β1. TGF‑β1 stimulation significantly decreased the mRNA levels of C1GalT1 and Cosmc. TGF‑β1 may be key in controlling the glycosylation of IgA1, in part via the downregulation of C1GalT1 and Cosmc.
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Affiliation(s)
- Jun Xiao
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Manting Wang
- Department of Nephrology, Affiliated Jiujiang Hospital of Nanchang University, Jiujiang, Jiangxi 332000, P.R. China
| | - Dawei Xiong
- Institute of Microbiology, Jiangxi Academy of Sciences, Nanchang, Jiangxi 330096, P.R. China
| | - Ying Wang
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Qiuyue Li
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Jing Zhou
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Qinkai Chen
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
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93
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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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94
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Lafayette RA, Canetta PA, Rovin BH, Appel GB, Novak J, Nath KA, Sethi S, Tumlin JA, Mehta K, Hogan M, Erickson S, Julian BA, Leung N, Enders FT, Brown R, Knoppova B, Hall S, Fervenza FC. A Randomized, Controlled Trial of Rituximab in IgA Nephropathy with Proteinuria and Renal Dysfunction. J Am Soc Nephrol 2016; 28:1306-1313. [PMID: 27821627 DOI: 10.1681/asn.2016060640] [Citation(s) in RCA: 147] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 09/11/2016] [Indexed: 11/03/2022] Open
Abstract
IgA nephropathy frequently leads to progressive CKD. Although interest surrounds use of immunosuppressive agents added to standard therapy, several recent studies have questioned efficacy of these agents. Depleting antibody-producing B cells potentially offers a new therapy. In this open label, multicenter study conducted over 1-year follow-up, we randomized 34 adult patients with biopsy-proven IgA nephropathy and proteinuria >1 g/d, maintained on angiotensin-converting enzyme inhibitors or angiotensin receptor blockers with well controlled BP and eGFR<90 ml/min per 1.73 m2, to receive standard therapy or rituximab with standard therapy. Primary outcome measures included change in proteinuria and change in eGFR. Median baseline serum creatinine level (range) was 1.4 (0.8-2.4) mg/dl, and proteinuria was 2.1 (0.6-5.3) g/d. Treatment with rituximab depleted B cells and was well tolerated. eGFR did not change in either group. Rituximab did not alter the level of proteinuria compared with that at baseline or in the control group; three patients in each group had ≥50% reduction in level of proteinuria. Serum levels of galactose-deficient IgA1 or antibodies against galactose-deficient IgA1 did not change. In this trial, rituximab therapy did not significantly improve renal function or proteinuria assessed over 1 year. Although rituximab effectively depleted B cells, it failed to reduce serum levels of galactose-deficient IgA1 and antigalactose-deficient IgA1 antibodies. Lack of efficacy of rituximab, at least at this stage and severity of IgA nephropathy, may reflect a failure of rituximab to reduce levels of specific antibodies assigned salient pathogenetic roles in IgA nephropathy.
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Affiliation(s)
- Richard A Lafayette
- Division of Nephrology and Hypertension, Stanford University, Stanford, California
| | - Pietro A Canetta
- Division of Nephrology and Hypertension, Columbia University Medical Center, New York, New York
| | - Brad H Rovin
- Division of Nephrology, Ohio State University, Columbus, Ohio
| | - Gerald B Appel
- Division of Nephrology and Hypertension, Columbia University Medical Center, New York, New York
| | | | | | - Sanjeev Sethi
- Department of Laboratory Medicine and Pathology, and
| | - James A Tumlin
- Division of Nephrology, University of Tennessee, Chattanooga, Tennessee; and
| | - Kshama Mehta
- Division of Nephrology and Hypertension, Stanford University, Stanford, California
| | | | | | - Bruce A Julian
- Departments of Microbiology and.,Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | | | - Felicity T Enders
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota
| | | | - Barbora Knoppova
- Departments of Microbiology and.,Department of Immunology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
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95
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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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96
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Galactose-Deficient IgA1 as a Candidate Urinary Polypeptide Marker of IgA Nephropathy? DISEASE MARKERS 2016; 2016:7806438. [PMID: 27647947 PMCID: PMC5018335 DOI: 10.1155/2016/7806438] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 06/23/2016] [Accepted: 07/12/2016] [Indexed: 11/17/2022]
Abstract
In patients with IgA nephropathy (IgAN), circulatory IgA1 and IgA1 in mesangial deposits contain elevated amounts of galactose-deficient IgA1 (Gd-IgA1). We hypothesized that a fraction of Gd-IgA1 from the glomerular deposits and/or circulation may be excreted into the urine and thus represent a disease-specific biomarker. Levels of urinary IgA and Gd-IgA1 were determined in 207 patients with IgAN, 205 patients with other renal diseases, and 57 healthy controls, recruited in USA, Japan, and Italy. Urinary IgA was similarly elevated in patients with IgAN and renal-disease controls compared with healthy controls. However, urinary Gd-IgA1 levels were higher in patients with IgAN (IgAN, 28.0 ± 17.9; disease controls, 20.6 ± 17.4 units/mg urinary creatinine; P < 0.0001). Lectin western blotting data confirmed these results. In IgAN patients, levels of urinary Gd-IgA1 correlated with proteinuria (P < 0.001). When we purified IgA from serum and urine of an IgAN patient, the relative proportion of Gd-IgA1 to total IgA1 was higher in the urine compared with serum, suggesting selective excretion of Gd-IgA1 in IgAN. In summary, urinary excretion of Gd-IgA1 was elevated in patients with IgAN and the urinary Gd-IgA1 levels correlated with proteinuria. Urinary Gd-IgA1 may thus represent a disease-specific biomarker of IgAN.
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97
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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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98
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Mestecky J, Novak J, Moldoveanu Z, Raska M. IgA nephropathy enigma. Clin Immunol 2016; 172:72-77. [PMID: 27444044 DOI: 10.1016/j.clim.2016.07.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 07/10/2016] [Indexed: 01/03/2023]
Abstract
IgA nephropathy (IgAN) is the leading cause of primary glomerulonephritis in the world. The disease is characterized by the presence of IgA-containing immune complexes in the circulation and in mesangial deposits with ensuing glomerular injury. Although in humans there are two IgA subclasses, only IgA1 molecules are involved. The exclusivity of participation of IgA1 in IgAN prompted extensive structural and immunological studies of the unique hinge region (HR) of IgA1, which is absent in otherwise highly homologous IgA2. HR of IgA1 with altered O-glycans serves as an antigen recognized by autoantibodies specific for aberrant HR glycans leading to the generation of nephritogenic immune complexes. However, there are several unresolved questions concerning the phylogenetic origin of human IgA1 HR, the structural basis of its antigenicity, the origin of antibodies specific for HR with altered glycan moieties, the regulatory defects in IgA1 glycosylation pathways, and the potential approaches applicable to the disease-specific interventions in the formation of nephritogenic immune complexes. This review focuses on the gaps in our knowledge of molecular and cellular events that are involved in the immunopathogenesis of IgAN.
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Affiliation(s)
- Jiri Mestecky
- University of Alabama at Birmingham, Department of Microbiology, Birmingham, AL, USA; First School of Medicine, Department of Immunology and Microbiology, Charles University, Prague, Czech Republic; Czech Academy of Sciences, Institute of Microbiology, Prague, Czech Republic.
| | - Jan Novak
- University of Alabama at Birmingham, Department of Microbiology, Birmingham, AL, USA
| | - Zina Moldoveanu
- University of Alabama at Birmingham, Department of Microbiology, Birmingham, AL, USA
| | - Milan Raska
- University of Alabama at Birmingham, Department of Microbiology, Birmingham, AL, USA; Palacky University, Faculty of Medicine and Dentistry and University Hospital, Department of Immunology, Olomouc, Czech Republic
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99
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Abstract
We have summarized the latest findings on markers for progression of immunoglobulin A (IgA) nephropathy (IgAN), the most common primary glomerulonephritis with a high prevalence among end-stage renal disease (ESRD) patients. The clinical predictors of renal outcome in IgAN nephropathy, such as proteinuria, hypertension, and decreased estimated glomerular filtration rate (eGFR) at the time of the diagnosis, are well known. The Oxford classification of IgAN identified four types of histological lesions (known as the MEST score) associated with the development of ESRD and/or a 50 % reduction in eGFR. In addition, the role of genetic risk factors associated with IgAN is being elucidated by genome-wide association studies, with multiple risk alleles described. Recently, biomarkers in serum (galactose-deficient IgA1, IgA/IgG autoantibodies against galactose-deficient IgA1, and soluble CD 89-IgA complexes) and urine (soluble transferrin receptor, interleukin-6/epidermal growth factor ratio, fractalkine, laminin G-like 3 peptide, κ light chains, and mannan-binding lectin) have been identified. Some of these biomarkers may represent candidates for the development of noninvasive diagnostic tests, that would be useful for detection of subclinical disease activity, monitoring disease progression, assessment of treatment, and at the same time circumventing the complications associated with renal biopsies. These advances, along with future disease-specific therapy, will be helpful in improving the treatment effectiveness, prognosis, and the quality of life in connection with IgAN.
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100
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Knoppova B, Reily C, Maillard N, Rizk DV, Moldoveanu Z, Mestecky J, Raska M, Renfrow MB, Julian BA, Novak J. The Origin and Activities of IgA1-Containing Immune Complexes in IgA Nephropathy. Front Immunol 2016; 7:117. [PMID: 27148252 PMCID: PMC4828451 DOI: 10.3389/fimmu.2016.00117] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Accepted: 03/15/2016] [Indexed: 12/12/2022] Open
Abstract
IgA nephropathy (IgAN) is the most common primary glomerulonephritis, frequently leading to end-stage renal disease, as there is no disease-specific therapy. IgAN is diagnosed from pathological assessment of a renal biopsy specimen based on predominant or codominant IgA-containing immunodeposits, usually with complement C3 co-deposits and with variable presence of IgG and/or IgM. The IgA in these renal deposits is galactose-deficient IgA1, with less than a full complement of galactose residues on the O-glycans in the hinge region of the heavy chains. Research from the past decade led to the definition of IgAN as an autoimmune disease with a multi-hit pathogenetic process with contributing genetic and environmental components. In this process, circulating galactose-deficient IgA1 (autoantigen) is bound by antiglycan IgG or IgA (autoantibodies) to form immune complexes. Some of these circulating complexes deposit in glomeruli, and thereby activate mesangial cells and induce renal injury through cellular proliferation and overproduction of extracellular matrix components and cytokines/chemokines. Glycosylation pathways associated with production of the autoantigen and the unique characteristics of the corresponding autoantibodies in patients with IgAN have been uncovered. Complement likely plays a significant role in the formation and the nephritogenic activities of these complexes. Complement activation is mediated through the alternative and lectin pathways and probably occurs systemically on IgA1-containing circulating immune complexes as well as locally in glomeruli. Incidence of IgAN varies greatly by geographical location; the disease is rare in central Africa but accounts for up to 40% of native-kidney biopsies in eastern Asia. Some of this variation may be explained by genetically determined influences on the pathogenesis of the disease. Genome-wide association studies to date have identified several loci associated with IgAN. Some of these loci are associated with the increased prevalence of IgAN, whereas others, such as deletion of complement factor H-related genes 1 and 3, are protective against the disease. Understanding the molecular mechanisms and genetic and biochemical factors involved in formation and activities of pathogenic IgA1-containing immune complexes will enable the development of future disease-specific therapies as well as identification of non-invasive disease-specific biomarkers.
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Affiliation(s)
- Barbora Knoppova
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
| | - Colin Reily
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nicolas Maillard
- Université Jean Monnet, Saint Etienne, France
- PRES Université de Lyon, Lyon, France
| | - Dana V. Rizk
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Zina Moldoveanu
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jiri Mestecky
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Milan Raska
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
| | - Matthew B. Renfrow
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Bruce A. Julian
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
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