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Larsen ML, Troldborg A, Toonen EJM, Hurler L, Prohaszka Z, Cervenak L, Gudmann Hansen A, Thiel S. Differentiating between activation via the lectin or the classical complement pathway in patients with systemic lupus erythematosus. Clin Exp Immunol 2023; 214:18-25. [PMID: 37407023 PMCID: PMC10711355 DOI: 10.1093/cei/uxad070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/11/2023] [Accepted: 07/05/2023] [Indexed: 07/07/2023] Open
Abstract
Complement activation is a hallmark of systemic lupus erythematosus (SLE) and can proceed through the classical (CP), lectin (LP), or alternative pathway (AP). When managing SLE patients, pathway-specific complement activation is rarely monitored as clinical assays are unavailable. In this study, we aim to differentiate between CP- or LP-mediated complement activation in SLE patients by quantifying pathway-specific protein complexes, namely C1s/C1-inhibitor (C1-INH) (CP-specific activation) and MASP-1/C1-INH (LP-specific activation). Levels for both complexes were assessed in 156 SLE patients and 50 controls using two newly developed ELISAs. We investigated whether pathway-specific complement activation was associated with disease activity and lupus nephritis (LN). Disease activity stratification was performed using SLEDAI scores assessed at inclusion. C1s/C1-INH concentrations were significantly increased in active SLE patients (SLEDAI ≥6) when compared with SLE patients with low disease activity (SLEDAI <6, P < 0.01) and correlated with SLEDAI score (r = .29, P < 0.01). In active LN, MASP-1/C1-INH plasma concentrations were significantly increased compared with nonactive LN (P = 0.02). No differences in MASP-1/C1-INH plasma concentrations were observed between active SLE patients and patients with low disease activity (P = 0.11) nor did we observe a significant correlation with disease activity (r = 0.12, P = 0.15). Our data suggest that the CP and the LP are activated in SLE. The CP is activated in active SLE disease, whereas activation of the LP might be more specific to disease manifestations like LN. Our results warrant further research into specific complement pathway activation in SLE patients to potentially improve specific-targeted and tailored-treatment approaches.
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Affiliation(s)
- Mads Lamm Larsen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Department of Rheumatology, Aarhus University Hospital, Aarhus, Denmark
| | - Anne Troldborg
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Department of Rheumatology, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | | | - Lisa Hurler
- Department of Internal Medicine and Haematology, Semmelweis University, Budapest, Hungary
| | - Zoltan Prohaszka
- Department of Internal Medicine and Haematology, Semmelweis University, Budapest, Hungary
- Research Group for Immunology and Haematology, Semmelweis University-Eötvös Loránd Research Network (Office for Supported Research Groups), Budapest, Hungary
| | - László Cervenak
- Department of Internal Medicine and Haematology, Semmelweis University, Budapest, Hungary
| | | | - Steffen Thiel
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
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Rekvig OP. The Anti-DNA Antibodies: Their Specificities for Unique DNA Structures and Their Unresolved Clinical Impact-A System Criticism and a Hypothesis. Front Immunol 2022; 12:808008. [PMID: 35087528 PMCID: PMC8786728 DOI: 10.3389/fimmu.2021.808008] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 12/14/2021] [Indexed: 12/12/2022] Open
Abstract
Systemic lupus erythematosus (SLE) is diagnosed and classified by criteria, or by experience, intuition and traditions, and not by scientifically well-defined etiology(ies) or pathogenicity(ies). One central criterion and diagnostic factor is founded on theoretical and analytical approaches based on our imperfect definition of the term “The anti-dsDNA antibody”. “The anti-dsDNA antibody” holds an archaic position in SLE as a unique classification criterium and pathogenic factor. In a wider sense, antibodies to unique transcriptionally active or silent DNA structures and chromatin components may have individual and profound nephritogenic impact although not considered yet – not in theoretical nor in descriptive or experimental contexts. This hypothesis is contemplated here. In this analysis, our state-of-the-art conception of these antibodies is probed and found too deficient with respect to their origin, structural DNA specificities and clinical/pathogenic impact. Discoveries of DNA structures and functions started with Miescher’s Nuclein (1871), via Chargaff, Franklin, Watson and Crick, and continues today. The discoveries have left us with a DNA helix that presents distinct structures expressing unique operations of DNA. All structures are proven immunogenic! Unique autoimmune antibodies are described against e.g. ssDNA, elongated B DNA, bent B DNA, Z DNA, cruciform DNA, or individual components of chromatin. In light of the massive scientific interest in anti-DNA antibodies over decades, it is an unexpected observation that the spectrum of DNA structures has been known for decades without being implemented in clinical immunology. This leads consequently to a critical analysis of historical and contemporary evidence-based data and of ignored and one-dimensional contexts and hypotheses: i.e. “one antibody - one disease”. In this study radical viewpoints on the impact of DNA and chromatin immunity/autoimmunity are considered and discussed in context of the pathogenesis of lupus nephritis.
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Affiliation(s)
- Ole Petter Rekvig
- Section of Autoimmunity, Fürst Medical Laboratory, Oslo, Norway.,Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
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3
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Abstract
The complement system is an ancient and phylogenetically conserved key danger sensing system that is critical for host defense against pathogens. Activation of the complement system is a vital component of innate immunity required for the detection and removal of pathogens. It is also a central orchestrator of adaptive immune responses and a constituent of normal tissue homeostasis. Once complement activation occurs, this system deposits indiscriminately on any cell surface in the vicinity and has the potential to cause unwanted and excessive tissue injury. Deposition of complement components is recognized as a hallmark of a variety of kidney diseases, where it is indeed associated with damage to the self. The provenance and the pathophysiological role(s) played by complement in each kidney disease is not fully understood. However, in recent years there has been a renaissance in the study of complement, with greater appreciation of its intracellular roles as a cell-intrinsic system and its interplay with immune effector pathways. This has been paired with a profusion of novel therapeutic agents antagonizing complement components, including approved inhibitors against complement components (C)1, C3, C5 and C5aR1. A number of clinical trials have investigated the use of these more targeted approaches for the management of kidney diseases. In this review we present and summarize the evidence for the roles of complement in kidney diseases and discuss the available clinical evidence for complement inhibition.
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Affiliation(s)
- Tilo Freiwald
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Bethesda, MD, United States; Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany
| | - Behdad Afzali
- Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany.
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Demir F, Troldborg A, Thiel S, Lassé M, Huesgen PF, Tomas NM, Wiech T, Rinschen MM. Proteolysis and inflammation of the kidney glomerulus. Cell Tissue Res 2021. [PMID: 33864499 DOI: 10.1007/s00441-021-03433-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 02/09/2021] [Indexed: 02/08/2023]
Abstract
Proteases play a central role in regulating renal pathophysiology and are increasingly evaluated as actionable drug targets. Here, we review the role of proteolytic systems in inflammatory kidney disease. Inflammatory kidney diseases are associated with broad dysregulations of extracellular and intracellular proteolysis. As an example of a proteolytic system, the complement system plays a significant role in glomerular inflammatory kidney disease and is currently under clinical investigation. Based on two glomerular kidney diseases, lupus nephritis, and membranous nephropathy, we portrait two proteolytic pathomechanisms and the role of the complement system. We discuss how profiling proteolytic activity in patient samples could be used to stratify patients for more targeted interventions in inflammatory kidney diseases. We also describe novel comprehensive, quantitative tools to investigate the entirety of proteolytic processes in a tissue sample. Emphasis is placed on mass spectrometric approaches that enable the comprehensive analysis of the complement system, as well as protease activities and regulation in general.
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Deghmane AE, Taha MK. Invasive Bacterial Infections in Subjects with Genetic and Acquired Susceptibility and Impacts on Recommendations for Vaccination: A Narrative Review. Microorganisms 2021; 9:467. [PMID: 33668334 DOI: 10.3390/microorganisms9030467] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/17/2021] [Accepted: 02/20/2021] [Indexed: 12/18/2022] Open
Abstract
The WHO recently endorsed an ambitious plan, “Defeating Meningitis by 2030”, that aims to control/eradicate invasive bacterial infection epidemics by 2030. Vaccination is one of the pillars of this road map, with the goal to reduce the number of cases and deaths due to Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus agalactiae. The risk of developing invasive bacterial infections (IBI) due to these bacterial species includes genetic and acquired factors that favor repeated and/or severe invasive infections. We searched the PubMed database to identify host risk factors that increase the susceptibility to these bacterial species. Here, we describe a number of inherited and acquired risk factors associated with increased susceptibility to invasive bacterial infections. The burden of these factors is expected to increase due to the anticipated decrease in cases in the general population upon the implementation of vaccination strategies. Therefore, detection and exploration of these patients are important as vaccination may differ among subjects with these risk factors and specific strategies for vaccination are required. The aim of this narrative review is to provide information about these factors as well as their impact on vaccination against the four bacterial species. Awareness of risk factors for IBI may facilitate early recognition and treatment of the disease. Preventive measures including vaccination, when available, in individuals with increased risk for IBI may prevent and reduce the number of cases.
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Rekvig OP. Autoimmunity and SLE: Factual and Semantic Evidence-Based Critical Analyses of Definitions, Etiology, and Pathogenesis. Front Immunol 2020; 11:569234. [PMID: 33123142 PMCID: PMC7573073 DOI: 10.3389/fimmu.2020.569234] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 08/31/2020] [Indexed: 12/17/2022] Open
Abstract
One cannot discuss anti-dsDNA antibodies and lupus nephritis without discussing the nature of Systemic lupus erythematosus (SLE). SLE is insistently described as a prototype autoimmune syndrome, with anti-dsDNA antibodies as a central biomarker and a pathogenic factor. The two entities, “SLE” and “The Anti-dsDNA Antibody,” have been linked in previous and contemporary studies although serious criticism to this mutual linkage have been raised: Anti-dsDNA antibodies were first described in bacterial infections and not in SLE; later in SLE, viral and parasitic infections and in malignancies. An increasing number of studies on classification criteria for SLE have been published in the aftermath of the canonical 1982 American College of Rheumatology SLE classification sets of criteria. Considering these studies, it is surprising to observe a nearby complete absence of fundamental critical/theoretical discussions aimed to explain how and why the classification criteria are linked in context of etiology, pathogenicity, or biology. This study is an attempt to prioritize critical comments on the contemporary definition and classification of SLE and of anti-dsDNA antibodies in context of lupus nephritis. Epidemiology, etiology, pathogenesis, and measures of therapy efficacy are implemented as problems in the present discussion. In order to understand whether or not disparate clinical SLE phenotypes are useful to determine its basic biological processes accounting for the syndrome is problematic. A central problem is discussed on whether the clinical role of anti-dsDNA antibodies from principal reasons can be accepted as a biomarker for SLE without clarifying what we define as an anti-dsDNA antibody, and in which biologic contexts the antibodies appear. In sum, this study is an attempt to bring to the forum critical comments on the contemporary definition and classification of SLE, lupus nephritis and anti-dsDNA antibodies. Four concise hypotheses are suggested for future science at the end of this analytical study.
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Affiliation(s)
- Ole Petter Rekvig
- Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway.,Fürst Medical Laboratory, Oslo, Norway
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Abstract
PURPOSE OF REVIEW Complement system dysfunction in terms of upregulation, downregulation, or dysregulation can create an imbalance of both host defense and inflammatory response leading to autoimmunity. In this review, we aimed at describing the role of complement system in host defense to inflection and in autoimmunity starting from the evidence from primary and secondary complement system deficiencies. RECENT FINDINGS Complement system has a determinant role in defense against infections: deficiencies of complement components are associated with increased susceptibility to infections. Primary complement system deficiencies are rare disorders that predispose to both infections and autoimmune diseases. Secondary complement system deficiencies are the result of the complement system activation with consumption. Complement system role in enhancing risk of infective diseases in secondary deficiencies has been demonstrated in patients affected by systemic autoimmune disorders, mainly systemic lupus erythematosus and vasculitis. SUMMARY The relationship between the complement system and autoimmunity appears paradoxical as both the deficiency and the activation contribute to inducing autoimmune diseases. In these conditions, the presence of complement deposition in affected tissues, decreased levels of complement proteins, and high levels of complement activation fragments in the blood and vessels have been documented.
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Puttaraksa K, Pirttinen H, Karvonen K, Nykky J, Naides SJ, Gilbert L. Parvovirus B19V Nonstructural Protein NS1 Induces Double-Stranded Deoxyribonucleic Acid Autoantibodies and End-Organ Damage in Nonautoimmune Mice. J Infect Dis 2020; 219:1418-1429. [PMID: 30346568 PMCID: PMC6468957 DOI: 10.1093/infdis/jiy614] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 10/17/2018] [Indexed: 02/06/2023] Open
Abstract
Background Viral infection is implicated in development of autoimmunity. Parvovirus B19 (B19V) nonstructural protein, NS1, a helicase, covalently modifies self double-stranded deoxyribonucleic acid (dsDNA) and induces apoptosis. This study tested whether resulting apoptotic bodies (ApoBods) containing virally modified dsDNA could induce autoimmunity in an animal model. Methods BALB/c mice were inoculated with (1) pristane-induced, (2) B19V NS1-induced, or (3) staurosporine-induced ApoBods. Serum was tested for dsDNA autoantibodies by Crithidia luciliae staining and enzyme-linked immunosorbent assay. Brain, heart, liver, and kidney pathology was examined. Deposition of self-antigens in glomeruli was examined by staining with antibodies to dsDNA, histones H1 and H4, and TATA-binding protein. Results The B19V NS1-induced ApoBod inoculation induced dsDNA autoantibodies in a dose-dependent fashion. Histopathological features of immune-mediated organ damage were evident in pristane-induced and NS1-induced ApoBod groups; severity scores were higher in these groups than in staurosporine-treated groups. Tissue damage was dependent on NS1-induced ApoBod dose. Nucleosomal antigens were deposited in target tissue from pristane-induced and NS1-induced ApoBod inoculated groups, but not in the staurosporine-induced ApoBod inoculated group. Conclusions This study demonstrated proof of principle in an animal model that virally modified dsDNA in apoptotic bodies could break tolerance to self dsDNA and induce dsDNA autoantibodies and end-organ damage.
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Affiliation(s)
- Kanoktip Puttaraksa
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyvaskyla, Finland
| | - Heidi Pirttinen
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyvaskyla, Finland
| | - Kati Karvonen
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyvaskyla, Finland
| | - Jonna Nykky
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyvaskyla, Finland
| | - Stanley J Naides
- Quest Diagnostics Nichols Institute, Immunology R&D, San Juan Capistrano, California
| | - Leona Gilbert
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyvaskyla, Finland
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9
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Cuitino L, Obreque J, Gajardo-Meneses P, Villarroel A, Crisóstomo N, San Francisco IF, Valenzuela RA, Méndez GP, Llanos C. Heme-Oxygenase-1 Is Decreased in Circulating Monocytes and Is Associated With Impaired Phagocytosis and ROS Production in Lupus Nephritis. Front Immunol 2019; 10:2868. [PMID: 31921135 PMCID: PMC6923251 DOI: 10.3389/fimmu.2019.02868] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 11/22/2019] [Indexed: 12/18/2022] Open
Abstract
Lupus nephritis (LN) is one of the most serious manifestations of systemic lupus erythematosus (SLE). Based on studies showing the potential role of heme oxygenase-1 (HO-1), an enzyme that catalyzes the degradation of heme and has anti-inflammatory properties in SLE development, we decided to explore HO-1 in LN. Accordingly, we evaluated HO-1 levels and function in circulating and infiltrating monocytes and neutrophils of LN patients. HO-1 levels were assessed in peripheral monocytes of LN patients and controls by flow cytometry and immunofluorescence microscopy. Phagocytosis and the production of reactive oxygen species (ROS) were evaluated to determine the effect of HO-1 in monocyte function. In addition, renal biopsies with proliferative LN were used to identify HO-1 in infiltrating cells and renal tissue by immunofluorescence and immunohistochemistry. Biopsies of healthy controls (HC) and patients who underwent nephrectomy were included as controls. Circulating pro-inflammatory monocytes and activated neutrophils were increased in LN patients. HO-1 levels were decreased in all subsets of monocytes and in activated neutrophils. LN monocytes showed increased phagocytosis and higher production of ROS than those of HC. When HO-1 was induced, phagocytosis and ROS levels became similar to those of HC. HO-1 was mostly expressed in renal tubular epithelial cells (RTEC). Renal tissue of LN patients showed lower levels of HO-1 than HC, whereas infiltrating immune cells of LN showed lower levels of HO-1 than biopsies of patients who had renal surgery. HO-1 is decreased in circulating monocytes and activated neutrophils of LN patients. HO-1 levels modulate the phagocytosis of LN monocytes and ROS production. HO-1 expression in RTEC might be an attempt of self-protection from inflammation.
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Affiliation(s)
- Loreto Cuitino
- Departamento de Inmunología Clínica y Reumatología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Javiera Obreque
- Departamento de Inmunología Clínica y Reumatología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Patricia Gajardo-Meneses
- Departamento de Inmunología Clínica y Reumatología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alejandra Villarroel
- Departamento de Anatomía Patológica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Natalia Crisóstomo
- Departamento de Inmunología Clínica y Reumatología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Ignacio F San Francisco
- Departamento de Urología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rodrigo A Valenzuela
- Departamento de Ciencias Químicas y Biológicas, Facultad de Salud, Universidad Bernardo O'Higgins, Santiago, Chile
| | - Gonzalo P Méndez
- Departamento de Anatomía Patológica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carolina Llanos
- Departamento de Inmunología Clínica y Reumatología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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Thiyagarajan D, Pedersen HL, Seredkina N, Horvei KD, Arranz L, Sonneveld R, Nijenhuis T, van der Vlag J, Rekvig OP. IL-1β Promotes a New Function of DNase I as a Transcription Factor for the Fas Receptor Gene. Front Cell Dev Biol 2018; 6:7. [PMID: 29468159 PMCID: PMC5807897 DOI: 10.3389/fcell.2018.00007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 01/23/2018] [Indexed: 12/26/2022] Open
Abstract
Recently we described that endonuclease inactive DNase I translocated into the nucleus in response to increased endogenous IL-1β expression. Here, we demonstrate impact and function of translocated DNase I in tubular cells. Effect of cytokines on expression level and nuclear localisation of DNase I and corresponding levels of Fas receptor (FasR) and IL-1β were determined by confocal microscopy, qPCR and western blot analyses, in presence or absence of siRNA against IL-1β and DNase I mRNA. Nuclear DNase I bound to the FAS promotor region as determined by chromatin immuno-precipitation analysis. Data demonstrate that; (i) translocation of DNase I depended on endogenous de novo-expressed IL-1β, (ii) nuclear DNase I bound FAS DNA, (iii) FasR expression increased after translocation of DNase I, (iv) interaction of exogenous Fas ligand (FasL) with upregulated FasR induced apoptosis in human tubular cells stimulated with TNFα. Thus, translocated DNase I most probably binds the promoter region of the FAS gene and function as a transcription factor for FasR. In conclusion, DNase I not only executes chromatin degradation during apoptosis and necrosis, but also primes the cells for apoptosis by enhancing FasR expression.
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Affiliation(s)
- Dhivya Thiyagarajan
- RNA and Molecular Pathology Research Group, Department of Medical Biology, University Hospital of North Norway, Tromsø, Norway
| | - Hege L. Pedersen
- RNA and Molecular Pathology Research Group, Department of Medical Biology, University Hospital of North Norway, Tromsø, Norway
| | - Natalya Seredkina
- RNA and Molecular Pathology Research Group, Department of Medical Biology, University Hospital of North Norway, Tromsø, Norway
| | - Kjersti D. Horvei
- RNA and Molecular Pathology Research Group, Department of Medical Biology, University Hospital of North Norway, Tromsø, Norway
| | - Lorena Arranz
- Stem Cell Aging and Cancer Research Group, Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, Tromsø, Norway
| | - Ramon Sonneveld
- Department of Nephrology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Tom Nijenhuis
- Department of Nephrology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Johan van der Vlag
- Department of Nephrology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Ole P. Rekvig
- RNA and Molecular Pathology Research Group, Department of Medical Biology, University Hospital of North Norway, Tromsø, Norway
- Department of Radiology, University Hospital of North Norway, Tromsø, Norway
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Abstract
Lupus nephritis is an important cause of kidney failure in patients of Asian, African, or Hispanic descent. Its etiology and pathogenesis are multifactorial and remain to be elucidated. Accumulating evidence suggests that anti-double-stranded DNA (dsDNA) antibodies play a critical role in the pathogenesis, through its direct binding to cross-reactive antigens on resident renal cells or indirect binding through chromatin material to extracellular matrix components, resulting in complement activation, cell activation and proliferation, and induction of inflammatory and fibrotic processes. While tubulo-interstitial damage portends poor long-term renal prognosis, the mechanisms leading to tubulo-interstitial injury in lupus nephritis has received relatively less attention to date. Immune deposition along the tubular basement membrane is often observed in lupus nephritis and correlates with tubulo-interstitial infiltration of immune cells and interstitial fibrosis. Anti-dsDNA antibodies bind to resident renal cells, including proximal renal tubular epithelial cells, and contribute to renal inflammation and fibrosis. There is emerging evidence that epigenetic influence such as DNA methylation, histone modification, and microRNAs (miRs) also contribute to kidney fibrosis. Overexpression of miR-150 is observed in renal biopsies from patients with lupus nephritis and correlates with kidney fibrosis and chronicity score. Mycophenolate mofetil (MMF) is an established and effective standard-of-care therapy for patients with lupus nephritis. Accumulating data suggest that in addition to its immunosuppressive actions on lymphocyte proliferation, mycophenolic acid (MPA), the active metabolite of MMF, can exert a direct effect on nonimmune cells. Mediators of inflammation and fibrosis induced by anti-dsDNA antibodies in cultured proximal renal tubular epithelial cells are ameliorated by the addition of MPA, suggesting that in addition to its immunosuppressive actions, MPA may also have a beneficial effect in improving tubulo-interstitial inflammation and fibrosis through its direct action on proximal renal tubular epithelial cells.
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Affiliation(s)
- Susan Yung
- Department of Medicine, Queen Mary Hospital, University of Hong Kong, Pok Fu Lam, Hong Kong.
| | - Tak Mao Chan
- Department of Medicine, Queen Mary Hospital, University of Hong Kong, Pok Fu Lam, Hong Kong.
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Kim HJ, Hong YH, Kim YJ, Kim HS, Park JW, Do JY, Kim KJ, Bae SW, Kim CW, Lee CK. Anti-heparan sulfate antibody and functional loss of glomerular heparan sulfate proteoglycans in lupus nephritis. Lupus 2016; 26:815-824. [PMID: 28420046 DOI: 10.1177/0961203316678674] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Background The purpose of this study was to evaluate the features of heparan sulfate proteoglycans (HSPGs) as agrins of the glomerular basement membrane (GBM) and circulating anti-heparan sulfate (HS) antibodies in lupus nephritis, comparing titers among the following groups: lupus nephritis (LN), non-renal lupus, non-lupus nephritis, and healthy controls. Methods The stage of nephritis was determined based on the kidney biopsy. Alcian blue staining and immunohistochemical (IHC) staining for agrin were performed for histological evaluation of GBM HSPGs in normal glomeruli, non-lupus membranous glomerulonephritis (MGN), and lupus MGN. The results were used for measurement of the serum anti-HS antibody titers using an enzyme-linked immunosorbent assay (ELISA) in the following groups: 38 healthy controls, 38 non-lupus nephritis, 37 non-renal lupus, and 38 LN. Results Glomerulus HSPGs were stained bluish-green along the GBM with Alcian blue. However, IHC staining against agrin was almost completely negative in the lupus MGN group compared with the normal and non-lupus MGN groups, which showed brown staining of GBM. A higher level of anti-HS IgG was detected in LN compared with other groups, respectively. Higher titers were associated with the presence of SLE and nephritis. A higher degree of proteinuria normalized to glomerular filtration rate (eGFR) was observed in association with higher anti-HS antibody titers in LN. Conclusion This study demonstrated a functional loss of GBM HSPGs and higher levels of circulating anti-HS antibodies as a characteristic feature of lupus nephritis, suggesting their involvement in the pathogenesis of lupus nephritis and proteinuria.
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Affiliation(s)
- H-J Kim
- 1 Division of Rheumatology, Department of Internal Medicine, School of Medicine, Yeungnam University, Daegu, Korea
| | - Y-H Hong
- 1 Division of Rheumatology, Department of Internal Medicine, School of Medicine, Yeungnam University, Daegu, Korea
| | - Y-J Kim
- 2 Department of Pathology, School of Medicine, Kyungpook National University, Daegu, Korea
| | - H-S Kim
- 3 Department of Microbiology, School of Medicine, Yeungnam University, Daegu, Korea
| | - J-W Park
- 4 Division of Nephrology, Department of Internal Medicine, School of Medicine, Yeungnam University, Daegu, Korea
| | - J-Y Do
- 4 Division of Nephrology, Department of Internal Medicine, School of Medicine, Yeungnam University, Daegu, Korea
| | - K-J Kim
- 5 Department of Biomedical Laboratory Science, Daekyeung University, Gyeongsan-si, Gyeongbuk, Korea
| | - S-W Bae
- 1 Division of Rheumatology, Department of Internal Medicine, School of Medicine, Yeungnam University, Daegu, Korea
| | - C-W Kim
- 1 Division of Rheumatology, Department of Internal Medicine, School of Medicine, Yeungnam University, Daegu, Korea
| | - C-K Lee
- 1 Division of Rheumatology, Department of Internal Medicine, School of Medicine, Yeungnam University, Daegu, Korea
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13
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Rekvig OP, Thiyagarajan D, Pedersen HL, Horvei KD, Seredkina N. Future Perspectives on Pathogenesis of Lupus Nephritis: Facts, Problems, and Potential Causal Therapy Modalities. Am J Pathol 2016; 186:2772-2782. [PMID: 27664472 DOI: 10.1016/j.ajpath.2016.06.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 06/30/2016] [Indexed: 12/22/2022]
Abstract
Divergent incommensurable models have been developed to explain the pathogenesis of lupus nephritis. Most contemporary models favor a central role for anti-chromatin antibodies. How they exert their pathogenic effect has, however, endorsed conflicts that at least for now preclude insight into definitive pathogenic pathways. The following paradigms are contemporarily in conflict with each other: i) the impact of anti-double-stranded DNA (dsDNA) antibodies that cross-react with inherent renal antigens, ii) the impact of anti-dsDNA antibodies targeting exposed chromatin in glomeruli, and iii) the impact of relative antibody avidity for dsDNA, chromatin fragments, or cross-reacting antigens. Aside from these three themes, the pathogenic role of T cells in lupus nephritis is not clear. These different models should be tested through a collaboration between scientists belonging to the different paradigms. If it turns out that there are different pathogenic pathways in lupus nephritis, the emerging pathogenic mechanism(s) may be encountered with new individual causal therapy modalities. Today, therapy is still unspecific and far from interfering with the cause(s) of the disorder. This review attempts to describe what we know about processes that may cause lupus nephritis and how such basic processes may be affected if we can specifically interrupt them. Secondary inflammatory mechanisms, cytokine signatures, activation of complement, and other contributors to inflammation will not be discussed herein; rather, the events that trigger these factors will be discussed.
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Affiliation(s)
- Ole P Rekvig
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway; Department of Radiology, University Hospital of North Norway, Tromsø, Norway; Norwegian Center for Molecular Medicine, University of Oslo, Oslo, Norway.
| | - Dhivya Thiyagarajan
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
| | - Hege L Pedersen
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
| | - Kjersti D Horvei
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
| | - Natalya Seredkina
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
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Yung S, Chan TM. Anti-dsDNA antibodies and resident renal cells - Their putative roles in pathogenesis of renal lesions in lupus nephritis. Clin Immunol 2017; 185:40-50. [PMID: 27612436 DOI: 10.1016/j.clim.2016.09.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 09/01/2016] [Accepted: 09/04/2016] [Indexed: 01/19/2023]
Abstract
Lupus nephritis affects up to 70% of patients with systemic lupus erythematosus and is an important treatable cause of kidney failure. Cardinal features of lupus nephritis include loss of self-tolerance, production of autoantibodies, immune complex deposition and immune-mediated injury to the kidney, resulting in increased cell proliferation, apoptosis, and induction of inflammatory and fibrotic processes that destroy normal nephrons. The production anti-dsDNA antibodies is a cardinal feature in lupus and their level correlates with disease activity. In addition to the formation of immune complexes thereby triggering complement activation, how anti-dsDNA antibodies home to the kidney and induce pathological processes in the renal parenchyma remain to be fully elucidated. Data from our laboratory and other investigators show that the properties of anti-dsDNA antibodies vary between patients and change over time, and that anti-dsDNA antibodies could bind directly to integral cell surface molecules such as annexin II or α-actinin, or indirectly through chromatin material deposited on the cell surface. The binding of anti-dsDNA antibodies to mesangial cells and proximal renal tubular epithelial cells triggers downstream inflammatory and fibrotic pathways, which include the activation of the PKC and MAPK signaling pathways, increased secretion of pro-inflammatory cytokines and matrix protein deposition that contribute to pathological processes in the renal parenchyma.
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Pedersen HL, Horvei KD, Thiyagarajan D, Seredkina N, Rekvig OP. Murine and Human Lupus Nephritis: Pathogenic Mechanisms and Theoretical Strategies for Therapy. Semin Nephrol 2016; 35:427-38. [PMID: 26573545 DOI: 10.1016/j.semnephrol.2015.08.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lupus nephritis is one of the most serious manifestations of systemic lupus erythematosus, and represents one of the criteria implemented to classify systemic lupus erythematosus. Although studied for decades, no consensus has been reached related to the basic cellular, molecular, and immunologic mechanism(s) responsible for lupus nephritis. No causal treatments have been developed; therapy is approached mainly with nonspecific immunosuppressive medications. More detailed insight into disease mechanisms therefore is indispensable to develop new therapeutic strategies. In this review, contemporary knowledge on the pathogenic mechanisms of lupus nephritis is discussed based on recent data in murine and human lupus nephritis. Specific focus is given to the effect of anti-double-stranded DNA/antinucleosome antibodies in the kidneys and whether they bind exposed chromatin fragments in glomeruli or whether they bind inherent glomerular structures by cross-recognition. Overall, the data presented here favor the exposed chromatin model because we did not find any indication to substantiate the anti-double-stranded DNA antibody cross-reacting model. At the end of this review we present data on why chromatin fragments are expressed in the glomeruli of patients with lupus nephritis, and discuss how this knowledge can be used to direct the development of future therapies.
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Affiliation(s)
- Hege Lynum Pedersen
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway.
| | - Kjersti Daae Horvei
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
| | - Dhivya Thiyagarajan
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
| | - Natalya Seredkina
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
| | - Ole Petter Rekvig
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway; Department of Radiology, University Hospital of North Norway, Tromsø, Norway
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Abstract
Lupus nephritis is a major complication of systemic lupus erythematosus (SLE) and is associated with a high rate of morbidity and mortality. While many different immunologic and nonimmunologic factors contribute to disease expression in lupus nephritis, a large body of evidence suggests that the production of anti-DNA antibodies and the formation of glomerular immune deposits are important initial events in the pathogenesis of the disease. This review will summarize our current understanding of the differences between pathogenic and nonpathogenic autoantibodies, the mechanisms by which these autoantibodies induce renal injury and the effector mechanisms which are subsequently activated by the deposited autoantibodies that ultimately lead to the expression of the different lupus lesions.
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Affiliation(s)
- M Waldman
- Department of Medicine, Renal Electrolyte and Hypertension Division, University of Pennsylvania, Philadelphia 19104, USA
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Abstract
Interferon regulatory factor 5 (IRF5) has been demonstrated as a key transcription factor of the immune system, playing important roles in modulating inflammatory immune responses in numerous cell types including dendritic cells, macrophages, and B cells. As well as driving the expression of type I interferon in antiviral responses, IRF5 is also crucial for driving macrophages toward a proinflammatory phenotype by regulating cytokine and chemokine expression and modulating B-cell maturity and antibody production. This review highlights the functional importance of IRF5 in a disease setting, by discussing polymorphic mutations at the human Irf5 locus that lead to susceptibility to systemic lupus erythematosus, rheumatoid arthritis, and inflammatory bowel disease. In concordance with this, we also discuss lessons in IRF5 functionality learned from murine in vivo models of autoimmune disease and inflammation and hypothesize that modulation of IRF5 activity and expression could provide potential therapeutic benefits in the clinic.
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Affiliation(s)
- Hayley L Eames
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom.
| | - Alastair L Corbin
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Irina A Udalova
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom.
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Imran TF, Yick F, Verma S, Estiverne C, Ogbonnaya-Odor C, Thiruvarudsothy S, Reddi AS, Kothari N. Lupus nephritis: an update. Clin Exp Nephrol 2015; 20:1-13. [PMID: 26471017 DOI: 10.1007/s10157-015-1179-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 10/02/2015] [Indexed: 01/06/2023]
Abstract
Lupus nephritis (LN) is an inflammatory condition of the kidneys that encompasses various patterns of renal disease including glomerular and tubulointerstitial pathology. It is a major predictor of poor prognosis in patients with systemic lupus erythematosus (SLE). Genetic factors, including several predisposing loci, and environmental factors, such as EBV and ultraviolet light, have been implicated in the pathogenesis. It carries a high morbidity and mortality if left untreated. Renal biopsy findings are utilized to guide treatment. Optimizing risk factors such as proteinuria and hypertension with renin-angiotensin receptor blockade is crucial. Immunosuppressive therapy is recommended for patients with focal or diffuse proliferative lupus nephritis (Class III or IV) disease, and certain patients with membranous LN (Class V) disease. Over the past decade, immunosuppressive therapies have significantly improved long-term outcomes, but the optimal therapy for LN remains to be elucidated. Cyclophosphamide-based regimens, given concomitantly with corticosteroids, have improved survival significantly. Even though many patients achieve remission, the risk of relapse remains considerably high. Other treatments include hydroxychloroquine, mycofenolate mofetil, and biologic therapies such as Belimumab, Rituximab, and Abatacept. In this paper, we provide a review of LN, including pathogenesis, classification, and clinical manifestations. We will focus, though, on discussion of the established as well as emerging therapies for patients with proliferative and membranous lupus nephritis.
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Affiliation(s)
- Tasnim F Imran
- Department of Medicine, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA.
| | - Frederick Yick
- Department of Medicine, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA
| | - Suneet Verma
- Department of Medicine, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA.,Division of Nephrology, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA
| | - Christopher Estiverne
- Department of Medicine, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA
| | - Chinonye Ogbonnaya-Odor
- Department of Medicine, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA
| | - Srikanth Thiruvarudsothy
- Department of Medicine, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA
| | - Alluru S Reddi
- Department of Medicine, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA.,Division of Nephrology, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA
| | - Neil Kothari
- Department of Medicine, New Jersey Medical School, Rutgers, The State University of New Jersey, 185 South Orange Avenue, Newark, NJ, 07103, USA
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Abstract
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by a breakdown of self-tolerance, production of auto-antibodies and immune-mediated injury, resulting in damage accrual in multiple organs. Kidney involvement, termed lupus nephritis, is a major cause of morbidity and mortality that affects over half of the SLE population during the course of disease. The etiology of lupus nephritis is multifactorial and remains to be fully elucidated. Accumulating evidence suggests that in addition to forming immune complexes and triggering complement activation, anti-dsDNA antibodies contribute to the pathogenesis of lupus nephritis through binding, either directly or indirectly, to cross-reactive antigens or chromatin materials, respectively, to resident renal cells and/or extracellular matrix components, thereby triggering downstream cellular activation and proliferation as well as inflammatory and fibrotic processes. Several cross-reactive antigens that mediate anti-dsDNA antibody binding have been identified, such as annexin II and alpha-actinin. This review discusses the mechanisms through which anti-dsDNA antibodies contribute to immunopathogenesis in lupus nephritis. Corticosteroids combined with either mycophenolic acid (MPA) or cyclophosphamide is the current standard of care immunosuppressive therapy for severe lupus nephritis. This review also discusses recent data showing distinct effects of MPA and cyclophosphamide on inflammatory and fibrotic processes in resident renal cells.
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Affiliation(s)
- Susan Yung
- Department of Medicine, Queen Mary Hospital, University of Hong Kong , Hong Kong , China
| | - Tak Mao Chan
- Department of Medicine, Queen Mary Hospital, University of Hong Kong , Hong Kong , China
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Thiyagarajan D, Rekvig OP, Seredkina N. TNFα Amplifies DNaseI Expression in Renal Tubular Cells while IL-1β Promotes Nuclear DNaseI Translocation in an Endonuclease-Inactive Form. PLoS One 2015; 10:e0129485. [PMID: 26065428 PMCID: PMC4465975 DOI: 10.1371/journal.pone.0129485] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 05/08/2015] [Indexed: 11/18/2022] Open
Abstract
We have demonstrated that the renal endonuclease DNaseI is up-regulated in mesangial nephritis while down-regulated during progression of the disease. To determine the basis for these reciprocal DNaseI expression profiles we analyse processes accounting for an early increase in renal DNaseI expression. Main hypotheses were that i. the mesangial inflammation and secreted pro-inflammatory cytokines directly increase DNaseI protein expression in tubular cells, ii. the anti-apoptotic protein tumor necrosis factor receptor-associated protein 1 (Trap 1) is down-regulated by increased expression of DNaseI due to transcriptional interference, and iii. pro-inflammatory cytokines promote nuclear translocation of a variant of DNaseI. The latter hypothesis emerges from the fact that anti-DNaseI antibodies stained tubular cell nuclei in murine and human lupus nephritis. The present study was performed on human tubular epithelial cells stimulated with pro-inflammatory cytokines. Expression of the DNaseI and Trap 1 genes was determined by qPCR, confocal microscopy, gel zymography, western blot and by immune electron microscopy. Results from in vitro cell culture experiments were analysed for biological relevance in kidneys from (NZBxNZW)F1 mice and human patients with lupus nephritis. Central data indicate that stimulating the tubular cells with TNFα promoted increased DNaseI and reduced Trap 1 expression, while TNFα and IL-1β stimulation induced nuclear translocation of the DNaseI. TNFα-stimulation resulted in 3 distinct effects; increased DNaseI and IL-1β gene expression, and nuclear translocation of DNaseI. IL-1β-stimulation solely induced nuclear DNaseI translocation. Tubular cells stimulated with TNFα and simultaneously transfected with IL-1β siRNA resulted in increased DNaseI expression but no nuclear translocation. This demonstrates that IL-1β promotes nuclear translocation of a cytoplasmic variant of DNaseI since translocation clearly was not dependent on DNaseI gene activation. Nuclear translocated DNaseI is shown to be enzymatically inactive, which may point at a new, yet unknown function of renal DNaseI.
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Affiliation(s)
- Dhivya Thiyagarajan
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Ole Petter Rekvig
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
- Department of Radiology, University Hospital of North Norway, Tromsø, Norway
| | - Natalya Seredkina
- RNA and Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
- * E-mail:
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Troldborg A, Thiel S, Laska MJ, Deleuran B, Jensenius JC, Stengaard-Pedersen K. Levels in plasma of the serine proteases and associated proteins of the lectin pathway are altered in patients with systemic lupus erythematosus. J Rheumatol 2015; 42:948-51. [PMID: 25877499 DOI: 10.3899/jrheum.141163] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2015] [Indexed: 12/23/2022]
Abstract
OBJECTIVE To examine whether proteins of the lectin pathway of the complement system are involved in systemic lupus erythematosus (SLE) pathogenesis. METHODS Using time-resolved immunofluorometric assays, plasma levels of mannan-binding lectin (MBL)-associated serine proteases 1 (MASP-1), MASP-2, MASP-3, MBL-associated protein of 19 kDa (MAp19), and MAp44 were determined in 58 patients with SLE and 65 healthy controls (HC). RESULTS Plasma concentrations in patients with SLE were higher than HC regarding MASP-1, MASP-3, and MAp44 (p < 0.0001, 0.0003, and 0.0013). Complement factor 3 correlated negatively and anti-dsDNA positively with levels of MAp19 (p = 0.0035, p = 0.0133). CONCLUSION In SLE, plasma levels of MASP and MAp are altered and associated with SLE characteristics, supporting a role in SLE pathogenesis.
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Affiliation(s)
- Anne Troldborg
- From the Department of Rheumatology, Aarhus University Hospital; Department of Clinical Medicine, and Department of Biomedicine, Aarhus University, Aarhus, Denmark.A. Troldborg, MD, PhD candidate, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University; S. Thiel, Professor; M.J. Laska, PhD, Assistant Professor, Department of Biomedicine, Aarhus University; B. Deleuran, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Biomedicine, Aarhus University; J.C. Jensenius, DrMed, DrPhil, Professor, Department of Biomedicine, Aarhus University; K. Stengaard-Pedersen, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University.
| | - Steffen Thiel
- From the Department of Rheumatology, Aarhus University Hospital; Department of Clinical Medicine, and Department of Biomedicine, Aarhus University, Aarhus, Denmark.A. Troldborg, MD, PhD candidate, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University; S. Thiel, Professor; M.J. Laska, PhD, Assistant Professor, Department of Biomedicine, Aarhus University; B. Deleuran, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Biomedicine, Aarhus University; J.C. Jensenius, DrMed, DrPhil, Professor, Department of Biomedicine, Aarhus University; K. Stengaard-Pedersen, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University
| | - Magdalena Janina Laska
- From the Department of Rheumatology, Aarhus University Hospital; Department of Clinical Medicine, and Department of Biomedicine, Aarhus University, Aarhus, Denmark.A. Troldborg, MD, PhD candidate, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University; S. Thiel, Professor; M.J. Laska, PhD, Assistant Professor, Department of Biomedicine, Aarhus University; B. Deleuran, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Biomedicine, Aarhus University; J.C. Jensenius, DrMed, DrPhil, Professor, Department of Biomedicine, Aarhus University; K. Stengaard-Pedersen, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University
| | - Bent Deleuran
- From the Department of Rheumatology, Aarhus University Hospital; Department of Clinical Medicine, and Department of Biomedicine, Aarhus University, Aarhus, Denmark.A. Troldborg, MD, PhD candidate, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University; S. Thiel, Professor; M.J. Laska, PhD, Assistant Professor, Department of Biomedicine, Aarhus University; B. Deleuran, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Biomedicine, Aarhus University; J.C. Jensenius, DrMed, DrPhil, Professor, Department of Biomedicine, Aarhus University; K. Stengaard-Pedersen, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University
| | - Jens Christian Jensenius
- From the Department of Rheumatology, Aarhus University Hospital; Department of Clinical Medicine, and Department of Biomedicine, Aarhus University, Aarhus, Denmark.A. Troldborg, MD, PhD candidate, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University; S. Thiel, Professor; M.J. Laska, PhD, Assistant Professor, Department of Biomedicine, Aarhus University; B. Deleuran, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Biomedicine, Aarhus University; J.C. Jensenius, DrMed, DrPhil, Professor, Department of Biomedicine, Aarhus University; K. Stengaard-Pedersen, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University
| | - Kristian Stengaard-Pedersen
- From the Department of Rheumatology, Aarhus University Hospital; Department of Clinical Medicine, and Department of Biomedicine, Aarhus University, Aarhus, Denmark.A. Troldborg, MD, PhD candidate, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University; S. Thiel, Professor; M.J. Laska, PhD, Assistant Professor, Department of Biomedicine, Aarhus University; B. Deleuran, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Biomedicine, Aarhus University; J.C. Jensenius, DrMed, DrPhil, Professor, Department of Biomedicine, Aarhus University; K. Stengaard-Pedersen, DrMed, Professor, Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University
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Lai WL, Yeh TH, Chen PM, Chan CK, Chiang WC, Chen YM, Wu KD, Tsai TJ. Membranous nephropathy: a review on the pathogenesis, diagnosis, and treatment. J Formos Med Assoc 2015; 114:102-11. [PMID: 25558821 DOI: 10.1016/j.jfma.2014.11.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 11/07/2014] [Accepted: 11/12/2014] [Indexed: 11/25/2022] Open
Abstract
In adults, membranous nephropathy (MN) is a major cause of nephrotic syndrome. However, the etiology of approximately 75% of MN cases is idiopathic. Secondary causes of MN are autoimmune diseases, infection, drugs, and malignancy. The pathogenesis of MN involves formation of immune complex in subepithelial sites, but the definite mechanism is still unknown. There are three hypotheses about the formation of immune complex, including preformed immune complex, in situ immune-complex formation, and autoantibody against podocyte membrane antigen. The formation of immune complex initiates complement activation, which subsequently leads to glomerular damage. Recently, the antiphospholipase A2 receptor antibody was found to be associated with idiopathic MN. This finding may be useful in the diagnosis and prognosis of MN. The current treatment includes best supportive care, which consists of the use of angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers, lipid-lowering agents, and optimal control of blood pressure. Immunosuppressive agents should be used for patients who suffer from refractory proteinuria or complications associated with nephrotic syndrome. Existing evidence supports the use of a combination of steroid and alkylating agents. This article reviews the epidemiology, pathogenesis, diagnosis, and the treatment of MN.
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Affiliation(s)
- Wei Ling Lai
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Ting Hao Yeh
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Ping Min Chen
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Chieh Kai Chan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Wen Chih Chiang
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
| | - Yung Ming Chen
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Kwan Dun Wu
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Tun Jun Tsai
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
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Salmon JE, Pricop L, D'agati V. Immunopathology of systemic lupus erythematosus. Rheumatology (Oxford) 2015. [DOI: 10.1016/b978-0-323-09138-1.00128-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Ben-Ami Shor D, Blank M, Reuter S, Matthias T, Beiglass I, Volkov A, Barshack I, Shoenfeld Y. Anti-ribosomal-P antibodies accelerate lupus glomerulonephritis and induce lupus nephritis in naïve mice. J Autoimmun 2014; 54:118-26. [DOI: 10.1016/j.jaut.2014.02.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 02/18/2014] [Accepted: 02/26/2014] [Indexed: 11/24/2022]
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Abstract
The complement system plays a major role in the autoimmune disease, systemic lupus erythematosus (SLE). However, the role of complement in SLE is complex since it may both prevent and exacerbate the disease. In this review, we explore the latest findings in complement-focused research in SLE. C1q deficiency is the strongest genetic risk factor for SLE, although such deficiency is very rare. Various recently discovered genetic associations include mutations in the complement receptors 2 and 3 as well as complement inhibitors, the latter related to earlier onset of nephritis. Further, autoantibodies are a distinct feature of SLE that are produced as the result of an adaptive immune response and how complement can affect that response is also being reviewed. SLE generates numerous disease manifestations involving contributions from complement such as glomerulonephritis and the increased risk of thrombosis. Furthermore, since most of the complement system is present in plasma, complement is very accessible and may be suitable as biomarker for diagnosis or monitoring of disease activity. This review highlights the many roles of complement for SLE pathogenesis and how research has progressed during recent years.
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Affiliation(s)
- Jonatan Leffler
- Division of Medical Protein Chemistry, Department of Laboratory Medicine Malmö, Lund University, Malmö, Sweden Division of Cell Biology and Immunology, Telethon Kids Institute, University of Western Australia, Subiaco, Australia
| | - Anders A Bengtsson
- Department of Clinical Sciences, Section of Rheumatology, Lund University, Skåne University Hospital Lund, Lund, Sweden
| | - Anna M Blom
- Division of Medical Protein Chemistry, Department of Laboratory Medicine Malmö, Lund University, Malmö, Sweden
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Gagnon P, Nian R, Lee J, Tan L, Latiff SMA, Lim CL, Chuah C, Bi X, Yang Y, Zhang W, Gan HT. Nonspecific interactions of chromatin with immunoglobulin G and protein A, and their impact on purification performance. J Chromatogr A 2014; 1340:68-78. [DOI: 10.1016/j.chroma.2014.03.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 03/01/2014] [Accepted: 03/04/2014] [Indexed: 11/16/2022]
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Rekvig OP, Van der Vlag J. The pathogenesis and diagnosis of systemic lupus erythematosus: still not resolved. Semin Immunopathol 2014; 36:301-11. [PMID: 24763531 DOI: 10.1007/s00281-014-0428-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 04/01/2014] [Indexed: 12/14/2022]
Abstract
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with various clinical manifestations affecting different tissues. A characteristic feature of SLE is the presence of autoantibodies against double-stranded (ds)DNA, histones and nucleosomes, and other chromatin components. SLE is a prototype type III hypersensitivity reaction. Local deposition of anti-nuclear antibodies in complex with released chromatin induces serious inflammatory conditions by activation of the complement system. The severe renal manifestation, lupus nephritis, is classified based on histological findings in renal biopsies. Apoptotic debris, including chromatin, is present in the extracellular matrix and circulation of patients with SLE. This may be due to an aberrant process of apoptosis and/or insufficient clearance of apoptotic cells/chromatin. The non-cleared apoptotic debris may lead to activation of both the innate and adaptive immune systems. In addition, an aberrant presentation of peptides by antigen-presenting cells, disturbed selection processes for lymphocytes, and deregulated lymphocyte responses may be involved in the development of autoimmunity. In the present review, we briefly will summarize current knowledge on the pathogenesis of SLE. We will also critically discuss and challenge central issues that need to be addressed in order to fully understand the pathogenic mechanisms involved in the development of SLE and in order to have an improved diagnosis for SLE. Disappointingly, in our opinion, there are still more questions than answers for the pathogenesis, diagnosis, and treatment of SLE.
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AL-Ayadhi LY, Mostafa GA. Serum antinucleosome-specific antibody as a marker of autoimmunity in children with autism. J Neuroinflammation 2014; 11:69. [PMID: 24708718 PMCID: PMC3977681 DOI: 10.1186/1742-2094-11-69] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 02/10/2014] [Indexed: 11/24/2022] Open
Abstract
Background Increasing evidence of autoimmune phenomena in some individuals with autism could represent the presence of altered or inappropriate immune responses in this disorder. The role of the nucleosome in the induction of antibody response in some autoimmune-mediated tissue damage may provide novel targets for treatment. Due to the paucity of studies investigating the frequency of systemic auto-antibodies in autism, we are the first to investigate the frequency of antinucleosome-specific antibodies in a group of autistic children. Methods Serum antinucleosome-specific antibodies were measured by ELISA in 60 autistic children, between the ages of 3 and 12 years, in comparison to 60 healthy children. Autistic severity was assessed using the Childhood Autism Rating Scale (CARS). Results Autistic children had significantly higher serum antinucleosome-specific antibodies than healthy children (P <0.001). The seropositivity of antinucleosome-specific antibodies was found in 46.7% of autistic children. Autistic children with a family history of autoimmunity (40%) had a significantly higher frequency of serum antinucleosome-specific antibodies (83.3%) than patients without such a history (22.2%, P <0.001). Conclusions Serum levels of antinucleosome-specific antibodies were increased in some autistic children. However, these data should be treated with caution until further investigations are performed with a larger subject population to determine whether these antibodies have a role in the induction of autoimmunity in a subgroup of autistic children. The role of immunotherapy in children with autism should be also studied.
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Affiliation(s)
| | - Gehan Ahmed Mostafa
- Autism Research and Treatment Center, AL-Amodi Autism Research Chair, Department of Physiology, Faculty of Medicine, King Saud University, Riyadh, Saudi Arabia.
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Abstract
Many studies have explored the pathology of systemic lupus erythematosus (SLE), an autoimmune rheumatic disorder with a striking female predominance. Numerous autoimmune phenomena are present in this disease, which ultimately result in organ damage. However, the specific cellular and humoral mechanisms underlying the immune dysfunction are not yet fully understood. It is postulated that autoimmunity is based on the interaction of genetic predisposition, hormonal and environmental triggers that result in reduced tolerance to self-tissues. These phenomena could occur because of altered antigen presentation, abnormalities in B cell responses, increases in the function of T-helper cells, abnormal cytokine production, exaggerated effector responses, or loss of regulatory T cells or B cells. Abnormalities in all of these components of the immune response have been implicated to varying degrees in the pathogenesis of SLE. This chapter will attempt to provide a "state-of-the-art" review of the evidence about the mechanisms underlying the pathology of SLE.
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Seredkina N, Van Der Vlag J, Berden J, Mortensen E, Rekvig OP. Lupus nephritis: enigmas, conflicting models and an emerging concept. Mol Med 2013; 19:161-9. [PMID: 23752208 DOI: 10.2119/molmed.2013.00010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 06/04/2013] [Indexed: 01/02/2023] Open
Abstract
Autoantibodies to components of chromatin, which include double-stranded DNA (dsDNA), histones and nucleosomes, are central in the pathogenesis of lupus nephritis. How anti-chromatin autoantibodies exert their nephritogenic activity, however, is controversial. One model assumes that autoantibodies initiate inflammation when they cross-react with intrinsic glomerular structures such as components of membranes, matrices or exposed nonchromatin ligands released from cells. Another model suggests glomerular deposition of autoantibodies in complex with chromatin, thereby inducing classic immune complex-mediated tissue damage. Recent data suggest acquired error of renal chromatin degradation due to the loss of renal DNaseI enzyme activity is an important contributing factor to the development of lupus nephritis in lupus-prone (NZBxNZW)F1 mice and in patients with lupus nephritis. Down-regulation of DNaseI expression results in reduced chromatin fragmentation and in deposition of extracellular chromatin-IgG complexes in glomerular basement membranes in individuals who produce IgG anti-chromatin autoantibodies. The main focus of the present review is to discuss whether exposed chromatin fragments in glomeruli are targeted by potentially nephritogenic anti-dsDNA autoantibodies or if the nephritogenic activity of these autoantibodies is explained by cross-reaction with intrinsic glomerular constituents or if both models coexist in diseased kidneys. In addition, the role of silencing of the renal DNaseI gene and the biological consequences of reduced chromatin fragmentation in nephritic kidneys are discussed.
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Affiliation(s)
- Natalya Seredkina
- Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
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Gan HT, Lee J, Latiff SMA, Chuah C, Toh P, Lee WY, Gagnon P. Characterization and removal of aggregates formed by nonspecific interaction of IgM monoclonal antibodies with chromatin catabolites during cell culture production. J Chromatogr A 2013; 1291:33-40. [DOI: 10.1016/j.chroma.2013.03.028] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 03/06/2013] [Accepted: 03/06/2013] [Indexed: 10/27/2022]
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Fismen S, Thiyagarajan D, Seredkina N, Nielsen H, Jacobsen S, Elung-Jensen T, Kamper AL, Johansen SD, Mortensen ES, Rekvig OP. Impact of the tumor necrosis factor receptor-associated protein 1 (Trap1) on renal DNaseI shutdown and on progression of murine and human lupus nephritis. Am J Pathol 2012; 182:688-700. [PMID: 23273922 DOI: 10.1016/j.ajpath.2012.11.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 10/23/2012] [Accepted: 11/07/2012] [Indexed: 01/22/2023]
Abstract
Recent findings show that transformation of mild glomerulonephritis into end-stage disease coincides with shutdown of renal DNaseI expression in (NZBxNZW)F1 mice. Down-regulation of DNaseI results in reduced chromatin fragmentation and deposition of extracellular chromatin fragments in glomerular basement membranes where they appear in complex with IgG antibodies. Here, we implicate the anti-apoptotic and survival protein, tumor necrosis factor receptor-associated protein 1 (Trap1) in the disease process, based on the observation that annotated transcripts from this gene overlap with transcripts from the DNaseI gene. Furthermore, we translate these observations to human lupus nephritis. In this study, mouse and human DNaseI and Trap1 mRNA levels were determined by real-time quantitative PCR and compared with protein expression levels and clinical data. Cellular localization was analyzed by immune electron microscopy, IHC, and in situ hybridization. Data indicate that silencing of DNaseI gene expression correlates inversely with expression of the Trap1 gene. Our observations suggest that the mouse model is relevant for the aspects of disease progression in human lupus nephritis. Acquired silencing of the renal DNaseI gene has been shown to be important for progression of disease in both the murine and human forms of lupus nephritis. Early mesangial nephritis initiates a cascade of inflammatory signals that lead to up-regulation of Trap1 and a consequent down-regulation of renal DNaseI by transcriptional interference.
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Affiliation(s)
- Silje Fismen
- Molecular Pathology Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway.
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Palejwala NV, Walia HS, Yeh S. Ocular manifestations of systemic lupus erythematosus: a review of the literature. Autoimmune Dis 2012; 2012:290898. [PMID: 22811887 DOI: 10.1155/2012/290898] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Accepted: 05/31/2012] [Indexed: 01/14/2023] Open
Abstract
About one-third of patients suffering from systemic lupus erythematosus have ocular manifestations. The most common manifestation is keratoconjunctivitis sicca. The most vision threatening are retinal vasculitis and optic neuritis/neuropathy. Prompt diagnosis and treatment of eye disease is paramount as they are often associated with high levels of systemic inflammation and end-organ damage. Initial management with high-dose oral or IV corticosteroids is often necessary. Multiple "steroid-sparing" treatment options exist with the most recently studied being biologic agents.
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Yung S, Chan TM. Autoantibodies and resident renal cells in the pathogenesis of lupus nephritis: getting to know the unknown. Clin Dev Immunol 2012; 2012:139365. [PMID: 22761629 DOI: 10.1155/2012/139365] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 03/26/2012] [Indexed: 02/06/2023]
Abstract
Systemic lupus erythematosus is characterized by a breakdown of self-tolerance and production of autoantibodies. Kidney involvement (i.e., lupus nephritis) is both common and severe and can result in permanent damage within the glomerular, vascular, and tubulo-interstitial compartments of the kidney, leading to acute or chronic renal failure. Accumulating evidence shows that anti-dsDNA antibodies play a critical role in the pathogenesis of lupus nephritis through their binding to cell surface proteins of resident kidney cells, thereby triggering the downstream activation of signaling pathways and the release of mediators of inflammation and fibrosis. This paper describes the mechanisms through which autoantibodies interact with resident renal cells and how this interaction plays a part in disease pathogenesis that ultimately leads to structural and functional alterations in lupus nephritis.
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Khan SN, Cox JV, Nishimoto SK, Chen C, Fritzler MJ, Hendershot LM, Weigert M, Radic M. Intra-Golgi formation of IgM-glycosaminoglycan complexes promotes Ig deposition. J Immunol 2011; 187:3198-207. [PMID: 21841132 DOI: 10.4049/jimmunol.1101336] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Immune complexes arise from interactions between secreted Ab and Ags in the surrounding milieu. However, it is not known whether intracellular Ag-Ab interactions also contribute to the formation of extracellular immune complexes. In this study, we report that certain murine B cell hybridomas accumulate intracellular IgM and release large, spherical IgM complexes. The complexes (termed "spherons") reach 2 μm in diameter, detach from the cell surface, and settle out of solution. The spherons contain IgM multimers that incorporate the J chain and resist degradation by endoglycosidase H, arguing for IgM passage through the Golgi. Treatment of cells with inhibitors of proteoglycan synthesis, or incubation of spherons with chondroitinase ABC, degrades spherons, indicating that spheron formation and growth depend on interactions between IgM and glycosaminoglycans. This inference is supported by direct binding of IgM to heparin and hyaluronic acid. We conclude that, as a consequence of IgM binding to glycosaminoglycans, multivalent IgM-glycan complexes form in transit of IgM to the cell surface. Intra-Golgi formation of immune complexes could represent a new pathogenic mechanism for immune complex deposition disorders.
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Affiliation(s)
- Salar N Khan
- Department of Molecular Sciences, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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Abstract
The present review focuses on pathogenic molecular and transcriptional events in patients with lupus nephritis. These factors are renal DNaseI, exposed chromatin fragments and the corresponding chromatin-reactive autoantibodies. Lupus nephritis is the most serious complication in human systemic lupus erythematosus, and is characterised by deposition of chromatin fragment-IgG complexes in the mesangial matrix and glomerular basement membranes. The latter deposition defines end-stage disease. This event is stringently linked to a renal-restricted shutdown of expression of the DNaseI gene, as determined by loss of DNaseI mRNA level and DNaseI enzyme activity. The major aim of the present review is to generate new therapeutic strategies based on new insight into the disease pathogenesis.
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Affiliation(s)
- Annica Hedberg
- Molecular Pathology Research Group, Institute of Medical Biology, Faculty of Health Science, University of Tromsø, N-9037 Tromsø, Norway
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Mjelle JE, Rekvig OP, Van Der Vlag J, Fenton KA. Nephritogenic antibodies bind in glomeruli through interaction with exposed chromatin fragments and not with renal cross-reactive antigens. Autoimmunity 2011; 44:373-83. [DOI: 10.3109/08916934.2010.541170] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Salmon JE, Pricop L, D’agati V. Immunopathology of systemic lupus erythematosus. Rheumatology (Oxford) 2011. [DOI: 10.1016/b978-0-323-06551-1.00125-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Abstract
Production of anti-dsDNA antibodies is a hallmark of lupus nephritis, but how these antibodies deposit in organs and elicit inflammatory damage remains unknown. In this study, we sought to identify antigens on the surface of human mesangial cells (HMC) that mediate the binding of human anti-dsDNA antibodies and the subsequent pathogenic processes. We isolated anti-dsDNA antibodies from patients with lupus nephritis by affinity chromatography. We used multiple methods to identify and characterize antigens from the plasma membrane fraction of mesangial cells that crossreacted with the anti-dsDNA antibodies. We found that annexin II mediated the binding of anti-dsDNA antibodies to HMC. After binding to the mesangial cell surface, anti-dsDNA antibodies were internalized into the cytoplasm and nucleus. This also led to induction of IL-6 secretion and annexin II synthesis, mediated through activation of p38 MAPK, JNK, and AKT. Binding of anti-dsDNA antibodies to annexin II correlated with disease activity in human lupus nephritis. Glomerular expression of annexin II correlated with the severity of nephritis, and annexin II colocalized with IgG and C3 deposits in both human and murine lupus nephritis. Gene silencing of annexin II in HMC reduced binding of anti-dsDNA antibody and partially decreased IL-6 secretion. In summary, our data demonstrate that annexin II mediates the binding of anti-dsDNA antibodies to mesangial cells, contributing to the pathogenesis of lupus nephritis. This interaction provides a potential target for therapeutic intervention.
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Affiliation(s)
- Susan Yung
- Department of Medicine, University of Hong Kong, Queen Mary Hospital, Pokfulam Road, Hong Kong, China
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Deng GM, Liu L, Tsokos GC. Targeted tumor necrosis factor receptor I preligand assembly domain improves skin lesions in MRL/lpr mice. ACTA ACUST UNITED AC 2010; 62:2424-31. [PMID: 20506390 DOI: 10.1002/art.27534] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Skin disease is the second most common manifestation in patients with systemic lupus erythematosus (SLE). Tumor necrosis factor receptor (TNFR) preligand assembly domain (PLAD) has been found to block the effect of TNFalpha, and TNFRI PLAD (p60 PLAD) inhibits inflammatory arthritis. This study was undertaken to investigate whether TNFR PLAD limits inflammatory skin injury in a mouse model of SLE. METHODS Female MRL/lpr mice received p60 PLAD (100 microg/mouse intraperitoneally), p80 PLAD (100 microg/mouse intraperitoneally), or phosphate buffered saline (100 microl/mouse intraperitoneally) 3 times a week for 26 weeks, starting at age 6 weeks. RESULTS Immunohistochemistry studies demonstrated that TNFRI but not TNFRII was dominantly expressed in skin lesions in MRL/lpr mice. We found that TNFRI PLAD (p60 PLAD) but not TNFRII PLAD (p80 PLAD) protein significantly inhibited skin injury in the MRL/lpr mouse model of lupus. NF-kappaB, monocyte chemotactic protein 1, and inducible nitric oxide synthase expression in skin lesions were significantly inhibited by p60 PLAD. Lupus serum-induced monocyte differentiation into dendritic cells was reduced by p60 PLAD, but p60 PLAD did not reduce IgG deposition in the skin or improve the progression of kidney damage in MRL/lpr mice. CONCLUSION Our results indicate that TNFRI is involved in the expression of skin injury in MRL/lpr mice with lupus and that p60 PLAD or similar biologics may be of clinical value if applied locally.
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Affiliation(s)
- Guo-Min Deng
- Division of Rheumatology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS 937, Boston, MA 02115, USA.
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Li WX, Pan HF, Li LH, Zhang N, Li J, Fan YG, Feng JB, Tang XW, Chen H, Li XP, Ye DQ. Prevalence and clinical significance of 15 autoantibodies in patients with new-onset systemic lupus erythematosus. Ir J Med Sci 2010; 179:623-7. [PMID: 20694751 DOI: 10.1007/s11845-010-0543-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Accepted: 07/23/2010] [Indexed: 10/19/2022]
Abstract
INTRODUCTION It is necessary to assay multiple autoantibodies simultaneously in the same group of new-onset systemic lupus erythematosus (SLE) patient. AIM To determine the prevalence and clinical significance of 15 autoantibodies in patients with new-onset SLE. METHODS Twenty new-onset patients with SLE and 32 healthy individuals were enrolled in the present study. Serum levels of 15 autoantibodies were detected by enzyme linked immunosorbent assay. The clinical parameters of the patients were also recorded. RESULTS The positive rate of anti-ssDNA was the highest (85%). The positive rates of anti-dsDNA, anti-ssDNA, AHA, anti-SSA, anti-SSB, anti-Sm, anti-U1RNP, AnuA, and rRNP were significantly higher in SLE patients than in nomal controls. In terms of clinical manifestation, there were significant associations of rRNP with photaesthesia and of AHA with nephritis. CONCLUSION Clusters of autoantibodies were identified and associations of antibodies with symptoms were found in new-onset patients with SLE.
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Fismen S, Mortensen ES, Rekvig OP. Nuclease deficiencies promote end-stage lupus nephritis but not nephritogenic autoimmunity in (NZB × NZW) F1 mice. Immunol Cell Biol 2011; 89:90-9. [PMID: 20548325 DOI: 10.1038/icb.2010.75] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
New information has profoundly improved our insight into the processes that account for lupus nephritis. This review summarizes the data proving that secondary necrotic chromatin fragments are generated and retained in kidneys at time-points when the major renal nuclease Dnase-1 is selectively and severely downregulated. Second, we discuss data, which may indicate that nuclease deficiencies are not associated with autoimmunity to chromatin. Secondary to downregulation of renal Dnase-1, large chromatin fragment-immunoglobulin G complexes are accumulated in glomerular basement membranes of patients producing anti-chromatin autoantibodies. Exposure of chromatin in situ in glomeruli is the factor that renders anti-chromatin (anti-dsDNA and anti-nucleosome) antibodies nephritogenic. Without exposed chromatin, they circulate as non-pathogenic antibodies. This shows that acquired loss of renal Dnase-1 enzyme activity is a dominant event responsible for the progression of lupus nephritis into end-stage disease. Before the loss of Dnase-1, lupus-prone (NZB × NZW) F1 mice develop mild or silent nephritis with mesangial immune complex deposits, which correlates solely with onset of anti-dsDNA antibody production. The principal cellular and molecular requirements needed to produce these autoantibodies have been explained experimentally, but the mechanism(s) accounting for them in vivo in context of lupus nephritis have not yet been determined. However, published data show that defects in nucleases operational in apoptotic or necrotic cell death are not associated with the induction of nephritogenic anti-dsDNA autoantibodies. The data discussed in this study explain how an unusual exposure of chromatin may be a central factor in the evolution of lupus nephritis in (NZB x NZW) F1 mice, but not in promoting nephritogenic chromatin-specific autoimmunity.
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Manson JJ, Ma A, Rogers P, Mason LJ, Berden JH, van der Vlag J, D'Cruz DP, Isenberg DA, Rahman A. Relationship between anti-dsDNA, anti-nucleosome and anti-alpha-actinin antibodies and markers of renal disease in patients with lupus nephritis: a prospective longitudinal study. Arthritis Res Ther 2009; 11:R154. [PMID: 19828047 PMCID: PMC2787270 DOI: 10.1186/ar2831] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Revised: 10/03/2009] [Accepted: 10/14/2009] [Indexed: 01/23/2023] Open
Abstract
Introduction Glomerulonephritis is a major cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Deposition of autoantibodies in the glomeruli plays a key role in the development of lupus nephritis (LN). Different groups have proposed that either anti-nucleosome antibodies or antibodies that bind the intrinsic renal antigen, α-actinin, are central to the pathogenesis of LN. These theories have been based mainly on cross-sectional studies in patients and on experiments in animal models. No previous longitudinal studies have compared the relationships between levels of these antibodies and markers of renal function. We assessed how well anti-α-actinin, anti-nucleosome and anti-double-stranded DNA (anti-dsDNA) antibodies reflected renal outcome measures in patients with new-onset LN followed for up to 2 years. Methods Renal disease activity was monitored by measuring urine protein/creatinine ratio (PCR), serum albumin and a composite outcome of renal remission. At each time point, anti-nucleosome and anti-α-actinin antibodies were measured by enzyme-linked immunosorbent assay. High-avidity anti-dsDNA antibodies were measured using the Farrzyme assay. We analysed relationships between levels of the three antibodies and between antibody levels and renal outcome measures over time. Results Levels of anti-nucleosome and anti-dsDNA were positively correlated with each other (r = 0.6, P = 0.0001) but neither correlated with anti-α-actinin level. At baseline, mean anti-nucleosome levels were higher in patients with LN than in healthy controls (0.32 versus 0.01, P < 0.001). The same was true for anti-dsDNA antibodies (0.50 versus 0.07, P < 0.001) but not for anti-α-actinin (0.33 versus 0.29). Over the follow-up period, anti-nucleosome and anti-dsDNA levels associated positively with urine PCR (P = 0.041 and 0.051, respectively) and negatively with serum albumin (P = 0.027 and 0.032, respectively). Both anti-nucleosome and anti-dsDNA levels were significantly lower during renal remission than when renal disease was active (P = 0.002 and 0.003, respectively). However, there was no relationship between anti-α-actinin levels and urine PCR, serum albumin or remission status. Conclusions This prospective longitudinal clinical study is the first to compare levels of anti-nucleosome, anti-dsDNA and anti-α-actinin antibodies in the same patients with SLE. Our results support the concept that, in the majority of patients, anti-nucleosome antibodies play a major role in pathogenesis of LN, in contrast to anti-α-actinin antibodies.
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Affiliation(s)
- Jessica J Manson
- Centre for Rheumatology Research, University College London, Windeyer Institute, 46 Cleveland Street, London W1T 4JF, UK.
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Seredkina N, Zykova SN, Rekvig OP. Progression of murine lupus nephritis is linked to acquired renal Dnase1 deficiency and not to up-regulated apoptosis. Am J Pathol 2009; 175:97-106. [PMID: 19528352 DOI: 10.2353/ajpath.2009.080943] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The accumulation of apoptotic cells has been suggested as a possible mechanism of nucleosome conversion into self-antigens that may both initiate autoimmune responses and participate in immune complex deposition in lupus nephritis. In this study, we analyzed both the rate of transcription of apoptosis-related genes and the presence of activated apoptotic factors within kidneys of lupus-prone (NZBxNZW) F1 mice during disease progression. The results of this study demonstrated no activation of apoptotic pathways in kidneys of these lupus-prone mice at the time of appearance of anti-double standard DNA antibodies in serum, as well as the formation of mesangial immune deposits in glomeruli. In contrast, the transition of mesangial into membranoproliferative lupus nephritis coincided with an accumulation of activated caspase 3-positive cells in kidneys, in addition to a dramatic decrease in Dnase1 gene transcription. Highly reduced expression levels of the Dnase1 gene may be responsible for the accumulation of large chromatin-containing immune complexes in glomerular capillary membranes. Thus, the initiation of lupus nephritis is not linked to increased apoptotic activity in kidneys. The combined down-regulation of Dnase1 and the increased number of apoptotic cells, which is possibly due to their reduced clearance in affected kidneys, may together be responsible for the transformation of mild mesangial lupus nephritis into severe membranoproliferative, end-stage organ disease.
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Affiliation(s)
- Natalya Seredkina
- Department of Biochemistry, Institute of Medical Biology, University of Tromsø, Tromsø, Norway
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Fismen S, Hedberg A, Fenton KA, Jacobsen S, Krarup E, Kamper AL, Rekvig OP, Mortensen ES. Circulating chromatin-anti-chromatin antibody complexes bind with high affinity to dermo-epidermal structures in murine and human lupus nephritis. Lupus 2009; 18:597-607. [PMID: 19433459 DOI: 10.1177/0961203308100512] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Murine and human lupus nephritis are characterized by glomerular deposits of electron-dense structures (EDS). Dominant components of EDS are chromatin fragments and IgG antibodies. Whether glomerular EDS predispose for similar deposits in skin is unknown. We analysed (i) whether dermo-epidermal immune complex deposits have similar molecular composition as glomerular deposits, (ii) whether chromatin fragments bind dermo-epidermal structures, and (iii) whether deposits in nephritic glomeruli predispose for accumulation of similar deposits in skin. Paired skin and kidney biopsies from nephritic (NZBxNZW)F1 and MRL-lpr/lpr mice and from five patients with lupus nephritis were analysed by immunofluorescence, immune electron microscopy (IEM) and co-localization TUNEL IEM. Affinity of chromatin fragments for membrane structures was determined by surface plasmon resonance. Results demonstrated (i) presence of EDS containing chromatin fragments and IgG in both organs in nephritic patients, (ii) chromatin fragments possessed high affinity for dermo-epidermal laminins and collagens, (iii) glomerular immune complex deposits did not predict similar interstitial deposits in skin, although such complexes were present in capillary lumina in glomeruli and skin of all nephritic individuals. Thus, chromatin-IgG complexes accounting for lupus nephritis seem to reach skin through circulation, but other undetermined factors are required for these complexes to deposit within skin membranes.
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Affiliation(s)
- S Fismen
- Department of Pathology, University Hospital of Northern Norway, N-9038 Tromsø, Norway
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Souza A, da Silva LM, Oliveira FR, Roselino AMF, Louzada-Junior P. Anti-nucleosome and anti-chromatin antibodies are present in active systemic lupus erythematosus but not in the cutaneous form of the disease. Lupus 2009; 18:223-9. [DOI: 10.1177/0961203308096255] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The objective of this study is to investigate the presence of anti-nucleosome (anti-NCS) and anti-chromatin (anti-CRT) antibodies in patients with cutaneous lupus erythematosus (CLE) compared with active and inactive systemic lupus erythematosus (SLE). A total of 154 subjects were evaluated: 54 patients presenting CLE, 66 patients with active SLE and 34 with inactive SLE. Lupus activity was assessed using the disease activity index (SLEDAI). Anti-NCS and anti-CRT antibodies were detected by enzyme-linked immunosorbent assay (ELISA). Only one of 54 patients with CLE tested positive for both anti-NCS and anti-CRT antibodies. The prevalence of anti-CRT antibodies was significantly higher in active SLE (84.8%) when compared with inactive SLE (26.4%) and CLE (1.8%) ( P < 0.001). Anti-NCS antibodies were also more prevalent in active SLE patients (74.2%) than inactive SLE (11.7%) and CLE patients (1.8%) ( P < 0.001). The presence of anti-CRT and anti-NCS antibodies was correlated to disease activity in patients with SLE ( r = 0.4937, r = 0.5621, respectively). Furthermore, the detection of both antibodies was correlated with disease activity in patients with SLE who tested negative for anti-dsDNA antibodies ( r = 0.4754 for anti-NCS and r = 0.4281 for anti-CRT). The presence of these two auto-antibodies was strongly associated with renal damage in patients with SLE (OR = 13.1, for anti-CRT antibodies and OR = 25.83, for anti-NCS antibodies). The anti-NCS and anti-CRT antibodies were not found in CLE. In patients with SLE, there is a correlation of these antibodies with disease activity and active nephritis. When compared with anti-dsDNA antibodies, anti-NCS and anti-CRT antibodies were more sensitive in detecting disease activity and kidney damage in lupus patients.
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Affiliation(s)
- A Souza
- Division of Clinical Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil; Division of Dermatology, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil
| | - LM da Silva
- Division of Clinical Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil
| | - FR Oliveira
- Division of Clinical Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil
| | - AMF Roselino
- Division of Dermatology, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil
| | - P Louzada-Junior
- Division of Clinical Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil
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Fenton KA, Mjelle JE, Jakobsen S, Olsen R, Rekvig OP. Renal expression of polyomavirus large T antigen is associated with nephritis in human systemic lupus erythematosus. Mol Immunol 2008; 45:3117-24. [PMID: 18423862 DOI: 10.1016/j.molimm.2008.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 03/05/2008] [Accepted: 03/06/2008] [Indexed: 10/22/2022]
Abstract
We have demonstrated that glomerular expression of polyomavirus large T antigen (T-ag) in a binary tetracycline-regulated T-ag transgenic mouse model (i) terminated tolerance for nucleosomes, (ii) released complexes of nucleosomes and T-ag to the microenvironment from dead cells, and (iii) that these complexes bound induced anti-nucleosome antibodies and finally (iv) that they associated with glomerular membranes as immune complexes. This process may be relevant for human lupus nephritis, since productive polyomavirus infection is associated with this organ manifestation. Here, we compare nephritis in the T-ag transgenic mouse with nephritis in human SLE. Glomerular sections were analysed by transmission electron microscopy, immune electron microscopy (IEM) and by co-localization IEM and TUNEL IEM assays to compare morphological changes, composition of immune complexes and formation of nucleosome-T-ag complexes. Affinity of nucleosome-T-ag complexes for glomerular collagen IV and laminin was determined by surface plasmon resonance (SPR). Analyses revealed electron dense structures in both human and murine kidney samples. These EDS were shown to contain T-ag, DNA and histones, indicating that extra-cellular chromatin may originate from polyomavirus infected cells in human kidneys. SPR analyses demonstrated high affinity of nucleosomes and nucleosome-T-ag complexes for collagen IV and laminin. Complexes of nucleosomes, T-ag and anti-T-ag and anti-dsDNA antibodies bind glomerular membranes and contribute to the evolution of lupus nephritis in human SLE.
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Affiliation(s)
- Kristin Andreassen Fenton
- Department of Biochemistry, Institute of Medical Biology, University of Tromsø, N-9037 Tromsø, Norway
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