1
|
Matola AT, Fülöp A, Rojkovich B, Nagy G, Sármay G, Józsi M, Uzonyi B. Autoantibodies against complement factor B in rheumatoid arthritis. Front Immunol 2023; 14:1113015. [PMID: 36891314 PMCID: PMC9986603 DOI: 10.3389/fimmu.2023.1113015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 01/23/2023] [Indexed: 02/22/2023] Open
Abstract
Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder affecting the joints. Many patients carry anti-citrullinated protein autoantibodies (ACPA). Overactivation of the complement system seems to be part of the pathogenesis of RA, and autoantibodies against the pathway initiators C1q and MBL, and the regulator of the complement alternative pathway, factor H (FH), were previously reported. Our aim was to analyze the presence and role of autoantibodies against complement proteins in a Hungarian RA cohort. To this end, serum samples of 97 ACPA-positive RA patients and 117 healthy controls were analyzed for autoantibodies against FH, factor B (FB), C3b, C3-convertase (C3bBbP), C1q, MBL and factor I. In this cohort, we did not detect any patient with FH autoantibodies but detected C1q autoantibodies in four patients, MBL autoantibodies in two patients and FB autoantibodies in five patients. Since the latter autoantibodies were previously reported in patients with kidney diseases but not in RA, we set out to further characterize such FB autoantibodies. The isotypes of the analyzed autoantibodies were IgG2, IgG3, IgGκ, IgGλ and their binding site was localized in the Bb part of FB. We detected in vivo formed FB-autoanti-FB complexes by Western blot. The effect of the autoantibodies on the formation, activity and FH-mediated decay of the C3 convertase in solid phase convertase assays was determined. In order to investigate the effect of the autoantibodies on complement functions, hemolysis assays and fluid phase complement activation assays were performed. The autoantibodies partially inhibited the complement-mediated hemolysis of rabbit red blood cells, inhibited the activity of the solid phase C3-convertase and C3 and C5b-9 deposition on complement activating surfaces. In summary, in ACPA-positive RA patients we identified FB autoantibodies. The characterized FB autoantibodies did not enhance complement activation, rather, they had inhibitory effect on complement. These results support the involvement of the complement system in the pathomechanism of RA and raise the possibility that protective autoantibodies may be generated in some patients against the alternative pathway C3 convertase. However, further analyses are needed to assess the exact role of such autoantibodies.
Collapse
Affiliation(s)
- Alexandra T Matola
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary.,MTA-ELTE Complement Research Group, Eötvös Loránd Research Network (ELKH) at the Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Angéla Fülöp
- Buda Hospital of the Hospitaller Order of Saint John of God, Budapest, Hungary
| | | | - György Nagy
- Department of Rheumatology and Clinical Immunology, Semmelweis University, Budapest, Hungary.,Department of Internal Medicine and Oncology, Semmelweis University, Budapest, Hungary.,Heart and Vascular Center, Faculty of Medicine, Semmelweis University, Budapest, Hungary.,Department of Genetics, Cell- and Immunobiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
| | - Gabriella Sármay
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Mihály Józsi
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary.,MTA-ELTE Complement Research Group, Eötvös Loránd Research Network (ELKH) at the Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Barbara Uzonyi
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary.,MTA-ELTE Complement Research Group, Eötvös Loránd Research Network (ELKH) at the Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| |
Collapse
|
2
|
Overview on the role of complement-specific autoantibodies in diseases. Mol Immunol 2022; 151:52-60. [PMID: 36084516 DOI: 10.1016/j.molimm.2022.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 08/03/2022] [Accepted: 08/15/2022] [Indexed: 11/24/2022]
Abstract
The complement system is recognized as a major pathogenic or contributing factor in an ever-growing number of diseases. In addition to inherited factors, autoantibodies to complement proteins have been detected in various systemic and organ-specific disorders. These include antibodies directed against complement components, regulators and receptors, but also protein complexes such as autoantibodies against complement convertases. In some cases, the autoantibodies are relatively well characterized and a pathogenic role is incurred and their detection has diagnostic value. In other cases, the relevance of the autoantibodies is rather unclear. This review summarizes what we know of complement specific autoantibodies in diseases and identifies unresolved questions regarding their functional effect and relevance.
Collapse
|
3
|
Xu J, Chen G, Yan Z, Qiu M, Tong W, Zhang X, Zhang L, Zhu Y, Liu K. Effect of mannose-binding lectin gene polymorphisms on the risk of rheumatoid arthritis: Evidence from a meta-analysis. Int J Rheum Dis 2021; 24:300-313. [PMID: 33458965 PMCID: PMC7986746 DOI: 10.1111/1756-185x.14060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 12/25/2020] [Indexed: 12/19/2022]
Abstract
BACKGROUND The effect of mannose-binding lectin (MBL) gene polymorphisms on susceptibility of rheumatoid arthritis (RA) were evaluated in ethnically different populations, whereas the results were always inconsistent. MATERIALS AND METHODS Fourteen articles involving 36 datasets were recruited to evaluate the association between MBL gene polymorphisms and rheumatoid arthritis in a meta-analysis. The random or fixed effect models were used to evaluate the pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CIs). RESULTS Stratified analysis by ethnicities was conducted and the result revealed that rs1800450 (T vs C, OR = 1.32, 95% CI: 1.04-1.67, P < .05) and MBL-A/O (T vs C, OR = 1.20, 95% CI: 1.08-1.34, P < .001) were strongly associated with RA in Brazilian populations. In addition, the significant relationship between rs11003125 (T vs C, OR = 1.16, 95% CI: 1.06-1.26, P < .05) with RA were also observed in East Asian populations. Meanwhile, the inverse associations between rs5030737 with RA in East Asians and rs1800450 with RA in Indians were acquired. However, no association between any MBL polymorphism with RA susceptibility was confirmed in Caucasians. CONCLUSIONS The structural polymorphisms in exon 1 of MBL gene may significantly contribute to susceptibility and development of RA in Brazilian and Indian populations, whereas the functional polymorphisms in the promoter region were more likely to associate with RA in East Asians.
Collapse
Affiliation(s)
- Jinjian Xu
- School of Public HealthSun Yat‐Sen UniversityGuangzhouChina
- Department of Epidemiology and BiostatisticsSchool of Public HealthZhejiang UniversityHangzhouChina
| | - Gang Chen
- Affiliated Dongtai Hospital of Nantong UniversityDongtaiChina
| | - Zhen Yan
- Gaoxin Hospital of The First Affiliated Hospital of Nanchang UniversityNanchangChina
| | - Mochang Qiu
- Department of Clinical MedicineJiangxi Medical CollegeShangraoChina
| | - Wentao Tong
- Jingdezheng NO.1 People’s HospitalJingdezhenChina
| | | | - Li Zhang
- Department of Clinical MedicineJiangxi Medical CollegeShangraoChina
| | - Yimin Zhu
- Department of Epidemiology and BiostatisticsSchool of Public HealthZhejiang UniversityHangzhouChina
| | - Keqi Liu
- Department of Clinical MedicineJiangxi Medical CollegeShangraoChina
| |
Collapse
|
4
|
The Immunopathology of Complement Proteins and Innate Immunity in Autoimmune Disease. Clin Rev Allergy Immunol 2020; 58:229-251. [PMID: 31834594 DOI: 10.1007/s12016-019-08774-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The complement is a powerful cascade of the innate immunity and also acts as a bridge between innate and acquired immune defence. Complement activation can occur via three distinct pathways, the classical, alternative and lectin pathways, each resulting in the common terminal pathway. Complement activation results in the release of a range of biologically active molecules that significantly contribute to immune surveillance and tissue homeostasis. Several soluble and membrane-bound regulatory proteins restrict complement activation in order to prevent complement-mediated autologous damage, consumption and exacerbated inflammation. The crucial role of complement in the host homeostasis is illustrated by association of both complement deficiency and overactivation with severe and life-threatening diseases. Autoantibodies targeting complement components have been described to alter expression and/or function of target protein resulting in a dysregulation of the delicate equilibrium between activation and inhibition of complement. The spectrum of diseases associated with complement autoantibodies depends on which complement protein and activation pathway are targeted, ranging from autoimmune disorders to kidney and vascular diseases. Nevertheless, these autoantibodies have been identified as differential biomarkers for diagnosis or follow-up of disease only in a small number of clinical conditions. For some autoantibodies, a clear relationship with clinical manifestations has been identified, such as anti-C1q, anti-Factor H, anti-C1 Inhibitor antibodies and C3 nephritic factor. For other autoantibodies, the origin and the functional consequences still remain to be elucidated, questioning about the pathophysiological significance of these autoantibodies, such as anti-mannose binding lectin, anti-Factor I, anti-Factor B and anti-C3b antibodies. The detection of autoantibodies targeting complement components is performed in specialized laboratories; however, there is no consensus on detection methods and standardization of the assays is a real challenge. This review summarizes the current panorama of autoantibodies targeting complement recognition proteins of the classical and lectin pathways, associated proteases, convertases, regulators and terminal components, with an emphasis on autoantibodies clearly involved in clinical conditions.
Collapse
|
5
|
Ekdahl KN, Persson B, Mohlin C, Sandholm K, Skattum L, Nilsson B. Interpretation of Serological Complement Biomarkers in Disease. Front Immunol 2018; 9:2237. [PMID: 30405598 PMCID: PMC6207586 DOI: 10.3389/fimmu.2018.02237] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 09/10/2018] [Indexed: 01/07/2023] Open
Abstract
Complement system aberrations have been identified as pathophysiological mechanisms in a number of diseases and pathological conditions either directly or indirectly. Examples of such conditions include infections, inflammation, autoimmune disease, as well as allogeneic and xenogenic transplantation. Both prospective and retrospective studies have demonstrated significant complement-related differences between patient groups and controls. However, due to the low degree of specificity and sensitivity of some of the assays used, it is not always possible to make predictions regarding the complement status of individual patients. Today, there are three main indications for determination of a patient's complement status: (1) complement deficiencies (acquired or inherited); (2) disorders with aberrant complement activation; and (3) C1 inhibitor deficiencies (acquired or inherited). An additional indication is to monitor patients on complement-regulating drugs, an indication which may be expected to increase in the near future since there is now a number of such drugs either under development, already in clinical trials or in clinical use. Available techniques to study complement include quantification of: (1) individual components; (2) activation products, (3) function, and (4) autoantibodies to complement proteins. In this review, we summarize the appropriate indications, techniques, and interpretations of basic serological complement analyses, exemplified by a number of clinical disorders.
Collapse
Affiliation(s)
- Kristina N Ekdahl
- Rudbeck Laboratory C5:3, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden.,Centre of Biomaterials Chemistry, Linnaeus University, Kalmar, Sweden
| | - Barbro Persson
- Rudbeck Laboratory C5:3, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Camilla Mohlin
- Centre of Biomaterials Chemistry, Linnaeus University, Kalmar, Sweden
| | - Kerstin Sandholm
- Centre of Biomaterials Chemistry, Linnaeus University, Kalmar, Sweden
| | - Lillemor Skattum
- Section of Microbiology, Immunology and Glycobiology, Department of Laboratory Medicine, Clinical Immunology and Transfusion Medicine, Lund University, Lund, Sweden
| | - Bo Nilsson
- Rudbeck Laboratory C5:3, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| |
Collapse
|
6
|
Khanna S, Jaiswal KS, Gupta B. Managing Rheumatoid Arthritis with Dietary Interventions. Front Nutr 2017; 4:52. [PMID: 29167795 PMCID: PMC5682732 DOI: 10.3389/fnut.2017.00052] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 10/10/2017] [Indexed: 12/19/2022] Open
Abstract
Self-help by means of dietary interventions can help in management of various disorders including rheumatoid arthritis (RA), a debilitating autoimmune disease. Dietary interventions necessitate a widespread appeal for both patients as well as clinicians due to factors including affordability, accessibility, and presence of scientific evidences that demonstrate substantial benefits in reducing disease symptoms such as pain, joint stiffness, swelling, tenderness and associated disability with disease progression. However, there is still an uncertainty among the community about the therapeutic benefits of dietary manipulations for RA. In the present review, we provide an account of different diets and their possible molecular mechanism of actions inducing observed therapeutic benefits for remission and management of RA. We further indicate food that can be a potential aggravating factor for the disease or may help in symptomatic relief. We thereafter summarize and thereby discuss various diets and food which help in reducing levels of inflammatory cytokines in RA patients that may play an effective role in management of RA following proper patient awareness. We thus would like to promote diet management as a tool that can both supplement and complement present treatment strategies for a better patient health and recovery.
Collapse
Affiliation(s)
- Shweta Khanna
- Disease Biology Laboratory, School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
| | - Kumar Sagar Jaiswal
- Disease Biology Laboratory, School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
| | - Bhawna Gupta
- Disease Biology Laboratory, School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
| |
Collapse
|
7
|
Cordero OJ, Varela-Calviño R, López-González T, Grujic M, Juranic Z, Mouriño C, Hernández-Rodríguez Í, Rodríguez-López M, de la Iglesia BA, Pego-Reigosa JM. Anti-CD26 autoantibodies are involved in rheumatoid arthritis and show potential clinical interest. Clin Biochem 2017; 50:903-910. [DOI: 10.1016/j.clinbiochem.2017.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 05/19/2017] [Accepted: 06/05/2017] [Indexed: 11/25/2022]
|
8
|
Tripathy A, Khanna S, Padhan P, Smita S, Raghav S, Gupta B. Direct recognition of LPS drive TLR4 expressing CD8 + T cell activation in patients with rheumatoid arthritis. Sci Rep 2017; 7:933. [PMID: 28424490 PMCID: PMC5430440 DOI: 10.1038/s41598-017-01033-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 03/20/2017] [Indexed: 12/24/2022] Open
Abstract
Aberrant immune responses characterize autoimmune disorders like Rheumatoid Arthritis (RA) wherein lymphocytes are recognized as key players. Role of CD8+ T cells in RA has been less defined however we found that these cells are activated in RA patients with increased expression of cytolytic granules and inflammatory mediators thereby modulating immune responses contributing to disease severity. Though unconventional expression of different Toll Like Receptors (TLRs) on CD8+ T cells has been proposed but their expression and role in T cell activation and differentiation in RA still remains obscure. Herein we report, for the first time, an increased expression of TLR4 on peripheral CD8+ T cells of RA patients and its role in skewing CD8+ T cells towards activated and inflammatory phenotype thereby playing a significant role in pathogenesis and progression of RA. We found that the surface expression of TLR4 on CD8+ T cells directly correlates with disease severity. Moreover, these CD8+ T cells respond to the TLR4 ligand LPS and express robust amounts of cytotolytic and inflammatory molecules including TNFα and IFNγ. Our study hence identifies an important role for CD8+ T cells in orchestrating RA through TLR4 mediated activation and differentiation.
Collapse
Affiliation(s)
- Archana Tripathy
- School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneswar, Odisha, India
| | - Shweta Khanna
- School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneswar, Odisha, India
| | - Prasanta Padhan
- Department of Rheumatology, Kalinga Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | - Shuchi Smita
- Institute of Life Sciences, Bhubaneswar, Odisha, India
| | - Sunil Raghav
- Institute of Life Sciences, Bhubaneswar, Odisha, India
| | - Bhawna Gupta
- School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneswar, Odisha, India.
| |
Collapse
|
9
|
Dragon-Durey MA, Blanc C, Marinozzi MC, van Schaarenburg RA, Trouw LA. Autoantibodies against complement components and functional consequences. Mol Immunol 2013; 56:213-21. [PMID: 23790637 DOI: 10.1016/j.molimm.2013.05.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 05/10/2013] [Indexed: 12/12/2022]
Abstract
The complement system represents a major component of our innate immune defense. Although the physiological contribution of the complement system is beneficial, it can cause tissue damage when inappropriately activated or when it is a target of an autoantibody response. Autoantibodies directed against a variety of individual complement components, convertases, regulators and receptors have been described. For several autoantibodies the functional consequences are well documented and clear associations exist with clinical presentation, whereas for other autoantibodies targeting complement components this relation is currently insufficiently clear. Several anti-complement autoantibodies can also be detected in healthy controls, indicating that a second hit is required for such autoantibodies to induce or participate in pathology or alternatively that these antibodies are part of the natural antibody repertoire. In the present review, we describe autoantibodies against complement components and their functional consequences and discuss about their clinical relevance.
Collapse
|
10
|
Cai Y, Zhang W, Xiong S. Mannose-binding lectin blunts macrophage polarization and ameliorates lupus nephritis. PLoS One 2013; 8:e62465. [PMID: 23626823 PMCID: PMC3633861 DOI: 10.1371/journal.pone.0062465] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 03/20/2013] [Indexed: 12/31/2022] Open
Abstract
Background Deficiency in clearance of self nuclear antigens, including DNA, is the hallmark of systemic lupus erythematosus (SLE), a chronic autoimmnue disease characterized by the production of various autoantibodies, immune complex deposition and severe organ damage. Our previous studies revealed that administration of syngeneic BALB/c mice with activated lymphocyte-derived DNA (ALD-DNA) could induce SLE disease. Mannose-binding lectin (MBL), a secreted pattern recognition receptor with binding activity to DNA, has been proved to be a modulator of inflammation, but whether MBL takes responsibility for DNA clearance, modulates the DNA-mediated immune responses, and is involved in the development of DNA-induced SLE disease remain poorly understood. Methodology/Principal Findings The levels of serum MBL significantly decreased in lupus mice induced by ALD-DNA and were negatively correlated with SLE disease. MBL blunted macrophage M2b polarization by inhibiting the MAPK and NF-κB signaling while enhancing the activation of CREB. Furthermore, MBL suppressed the ability of ALD-DNA–stimulated macrophages to polarize T cells toward Th1 cells and Th17 cells. Importantly, MBL supplement in vivo could ameliorate lupus nephritis. Conclusion/Significance These results suggest MBL supplement could alleviate SLE disease and might imply a potential therapeutic strategy for DNA-induced SLE, which would further our understanding of the protective role of MBL in SLE disease.
Collapse
Affiliation(s)
- Yanxing Cai
- Department of Immunology and Institute for Immunobiology, Shanghai Medical College, Fudan University, Shanghai, People’s Republic of China
| | - Weijuan Zhang
- Department of Immunology and Institute for Immunobiology, Shanghai Medical College, Fudan University, Shanghai, People’s Republic of China
| | - Sidong Xiong
- Department of Immunology and Institute for Immunobiology, Shanghai Medical College, Fudan University, Shanghai, People’s Republic of China
- Institutes of Biology and Medical Sciences, Soochow University, Suzhou, People’s Republic of China
- * E-mail:
| |
Collapse
|
11
|
Biswas S, Sharma S, Saroha A, Bhakuni DS, Malhotra R, Zahur M, Oellerich M, Das HR, Asif AR. Identification of novel autoantigen in the synovial fluid of rheumatoid arthritis patients using an immunoproteomics approach. PLoS One 2013; 8:e56246. [PMID: 23418544 PMCID: PMC3572018 DOI: 10.1371/journal.pone.0056246] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 01/07/2013] [Indexed: 11/19/2022] Open
Abstract
Rheumatoid arthritis (RA) is a chronic, autoimmune and inflammatory joint disease with a poorly understood etiology. Despite widespread diagnostic use of anti-citrullinated protein antibodies and rheumatoid factor proteins there is a strong demand for novel serological biomarkers to improve the diagnosis this disease. The present study was aimed to identify novel autoantigens involved in rheumatoid arthritis (RA) pathogenesis through immune-proteomic strategy. Synovial fluid samples from clinically diagnosed RA patients were separated on two-dimensional gel electrophoresis (2-DE). Samples from patients with non-RA rheumatisms (osteoarthritis and trauma) were used as controls. Immunoreactive proteins were spotted by Western blotting followed by identification through Q-TOF mass spectrometer analysis. Forty Western blots were generated using plasma from ten individual RA patients and 33 reactive spots were identified, 20 from the high molecular weight (HMW) gel and 13 from the low molecular weight (LMW) gel. Among the 33 common immunogenic spots, 18 distinct autoantigens were identified, out of which 14 are novel proteins in this context. Expression analysis of five important proteins, vimentin, gelsolin, alpha 2 HS glycoprotein (AHSG), glial fibrillary acidic protein (GFAP), and α1B-glycoprotein (A1BG) by Western blot analysis using their specific antibodies revealed their higher expression in RA synovial fluid as compared to non-RA samples. Recombinantly expressed GFAP and A1BG protein were used to develop an in-house ELISA to quantify the amount of autoantibodies in the RA patients. RA patients revealed an increase in the expression of GFAP and A1BG in the plasma as compared to osteoarthritis patients. Therefore, GFAP and A1BG can be proposed as potential new autoantigens of diagnostic importance for RA subjects. Further characterization of these proteins in rheumatoid arthritis will be helpful in understanding the role of these proteins in the disease pathogenesis providing new diagnostic tool with better specificity and accurate detection of the disease.
Collapse
Affiliation(s)
- Sagarika Biswas
- Department of Genomics & Molecular Medicine, Institute of Genomics and Integrative Biology, New Delhi, India
- Department of Clinical Chemistry, University Medical Center Goettingen, Goettingen, Germany
| | - Saurabh Sharma
- Department of Genomics & Molecular Medicine, Institute of Genomics and Integrative Biology, New Delhi, India
| | - Ashish Saroha
- Department of Genomics & Molecular Medicine, Institute of Genomics and Integrative Biology, New Delhi, India
| | - D. S. Bhakuni
- Department of Clinical Immunology and Rheumatology, Army Hospital (Research and Referral), New Delhi, India
| | - Rajesh Malhotra
- Department of Orthopaedic, All India Institute of Medical Sciences, New Delhi, India
| | - Muzna Zahur
- Department of Biochemistry and Molecular Biology, University of Gujrat, Gujrat, Pakistan
| | - Michael Oellerich
- Department of Clinical Chemistry, University Medical Center Goettingen, Goettingen, Germany
| | - Hasi R. Das
- Department of Genomics & Molecular Medicine, Institute of Genomics and Integrative Biology, New Delhi, India
| | - Abdul R. Asif
- Department of Clinical Chemistry, University Medical Center Goettingen, Goettingen, Germany
- * E-mail:
| |
Collapse
|
12
|
Schaffer T, Flogerzi B, Schoepfer AM, Seibold F, Müller S. Increased titers of anti-Saccharomyces cerevisiae antibodies in Crohn's disease patients with reduced H-ficolin levels but normal MASP-2 activity. J Crohns Colitis 2013; 7:e1-10. [PMID: 22445443 DOI: 10.1016/j.crohns.2012.02.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 01/23/2012] [Accepted: 02/14/2012] [Indexed: 02/08/2023]
Abstract
BACKGROUND AND AIMS Mannan-binding lectin (MBL) and ficolins are microbial pattern recognition molecules that activate the lectin pathway of complement. We previously reported the association of MBL deficiency with anti-Saccharomyces cerevisiae antibodies (ASCA) in patients with Crohn's disease (CD). However, ASCA are also frequently found in MBL-proficient CD patients. Here we addressed expression/function of ficolins and MBL-associated serine protease-2 (MASP-2) regarding potential association with ASCA. METHODS ASCA titers and MBL, ficolin and MASP-2 concentrations were determined by ELISA in the serum of patients with CD, ulcerative colitis (UC), and in healthy controls. MASP-2 activity was determined by measuring complement C4b-fixation. Anti-MBL autoantibodies were detected by ELISA. RESULTS In CD and UC patients, L-ficolin concentrations were significantly higher compared to healthy controls (p<0.001 and p=0.029). In contrast, H-ficolin concentrations were slightly reduced in CD and UC compared to healthy controls (p=0.037 for UC vs. hc). CD patients with high ASCA titers had significantly lower H-ficolin concentrations compared to ASCA-low/negative CD patients (p=0.009). However, MASP-2 activity was not different in ASCA-negative and ASCA-positive CD patients upon both, ficolin- or MBL-mediated MASP-2 activation. Finally, anti-MBL autoantibodies were not over-represented in MBL-proficient ASCA-positive CD patients. CONCLUSIONS Our results suggest that low expression of H-ficolin may promote elevated ASCA titers in the ASCA-positive subgroup of CD patients. However, unlike MBL deficiency, we found no evidence for low expression of serum ficolins or reduced MASP-2 activity that may predispose to ASCA development.
Collapse
Affiliation(s)
- Thomas Schaffer
- Department of Clinical Research, Division of Gastroenterology, University Hospital Bern, University of Bern, Bern, Switzerland
| | | | | | | | | |
Collapse
|
13
|
Kilpatrick DC. Birds, babies and blood. Mol Immunol 2012; 55:35-47. [PMID: 22998851 DOI: 10.1016/j.molimm.2012.08.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 08/20/2012] [Accepted: 08/22/2012] [Indexed: 10/27/2022]
Abstract
This is an autobiographical review describing the author's career in immunology research and summarizing his current understanding of the areas involved. Contributions to autoimmunity, immune deficiency, transfusion immunology, HLA-disease associations, reproductive immunology, cellular therapies, and innate immunity are included; also discussion of medical research ethics and various research-related activities.
Collapse
Affiliation(s)
- David C Kilpatrick
- Scottish National Blood Transfusion Service, National Science Laboratory, Edinburgh, United Kingdom.
| |
Collapse
|
14
|
Boldt ABW, Goeldner I, de Messias-Reason IJT. Relevance of the lectin pathway of complement in rheumatic diseases. Adv Clin Chem 2012; 56:105-53. [PMID: 22397030 DOI: 10.1016/b978-0-12-394317-0.00012-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Due to its importance both in the clearance of pathogens that contribute as rheumatic etiological agents and in the disposal of apoptotic bodies and potential autoimmune initiators, deficiencies of the components of the lectin pathway of complement have been found to increase susceptibility and modulate the severity of most rheumatic disorders. This chapter introduces the general aspects of the structure, function, and genetics of lectin pathway components and summarizes current knowledge of the field regarding rheumatic diseases predisposition and modulation.
Collapse
Affiliation(s)
- Angelica B W Boldt
- Molecular Immunopathology Laboratory, Department of Medical Pathology, Federal University of Paraná, Curitiba, Brazil
| | | | | |
Collapse
|
15
|
Lakota K, Zigon P, Mrak-Poljsak K, Rozman B, Shoenfeld Y, Sodin-Semrl S. Antibodies against acute phase proteins and their functions in the pathogenesis of disease: A collective profile of 25 different antibodies. Autoimmun Rev 2011; 10:779-89. [DOI: 10.1016/j.autrev.2011.06.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 06/15/2011] [Indexed: 01/09/2023]
|
16
|
Saroha A, Biswas S, Chatterjee BP, Das HR. Altered glycosylation and expression of plasma alpha-1-acid glycoprotein and haptoglobin in rheumatoid arthritis. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 879:1839-43. [DOI: 10.1016/j.jchromb.2011.04.024] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 04/18/2011] [Accepted: 04/19/2011] [Indexed: 11/30/2022]
|
17
|
Saevarsdottir S, Ding B, Steinsson K, Grondal G, Valdimarsson H, Alfredsson L, Klareskog L, Padyukov L. Mannan Binding Lectin (MBL) genotypes coding for high MBL serum levels are associated with rheumatoid factor negative rheumatoid arthritis in never smokers. Arthritis Res Ther 2011; 13:R65. [PMID: 21496252 PMCID: PMC3132060 DOI: 10.1186/ar3321] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 02/24/2011] [Accepted: 04/15/2011] [Indexed: 12/15/2022] Open
Abstract
Introduction Previous studies have provided inconsistent results on whether variants in the MBL2 gene, coding for the complement-activating mannan-binding lectin (MBL) protein, associate with rheumatoid arthritis (RA). We re-evaluated this in context of the main environmental and genetic risk factors (smoking, HLA-DRB1 'shared epitope' (SE), PTPN22*620W), which predispose to rheumatoid factor (RF) and/or anti-citrullinated-protein antibody (ACPA)-positive RA. Methods In this population-based EIRA study, rheumatoid factor (RF), ACPA, smoking, SE and PTPN22*620W status was determined in incident RA cases and matched controls. MBL-high (n = 1330) and MBL-low (n = 1257) genotypes predicting MBL levels were constructed from four promoter and exon-1 polymorphisms in the MBL2 gene. Odds ratios with 95% confidence interval (OR, 95% CI) were calculated by logistic regression. In extended families (n = 316), previously reported data were re-analyzed, considering RF and smoking. Results MBL-high genotypes tended to be associated with RF-negative (OR = 1.20, 95% CI 0.96-1.51) but not RF-positive (OR = 1.00, 95% CI 0.83-1.20) RA. Results divided by ACPA status did not differ. When stratified for smoking, MBL-high genotype was strongly associated with RF-negative RA in never smokers (OR = 1.82, 95% CI 1.24-2.69) but not in ever smokers (OR = 0.96, 95% CI 0.73-1.30). In never smokers, the association was observed in both the RF-negative/ACPA-negative (OR = 1.67, 95% CI 1.10-2.55) and RF-negative/ACPA-positive subgroups (OR = 3.07, 95% CI 1.37-6.89), and remained on an SE/PTPN22*620W negative background. In the extended families, the reported association between high MBL and RA was in fact confined to never smokers. Conclusions High MBL may predispose to RF-negative RA but only in individuals who have never smoked. This illustrates the importance of phenotypic subgrouping in genetic studies.
Collapse
Affiliation(s)
- Saedis Saevarsdottir
- Rheumatology Unit, Department of Medicine, Karolinska University Hospital Solna, D2:01, 17176 Stockholm, Sweden.
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Zen M, Bassi N, Campana C, Bettio S, Tarricone E, Nalotto L, Ghirardello A, Doria A. Protective molecules and their cognate antibodies: new players in autoimmunity. AUTO- IMMUNITY HIGHLIGHTS 2010; 1:63-72. [PMID: 26000109 PMCID: PMC4389047 DOI: 10.1007/s13317-010-0010-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 09/08/2010] [Indexed: 12/21/2022]
Abstract
Impairment of the clearance of apoptotic material seems to contribute to autoantigen exposure, which can initiate or maintain an autoimmune response in predisposed individuals. Complement component C1q, Creactive protein (CRP), serum amyloid P (SAP), mannose-binding lectin (MBL), apolipoprotein A-1 (Apo A-1) and long pentraxin 3 (PTX3) are molecules involved in the removal of apoptotic bodies and pathogens, and in other antiinflammatory pathways. For this reason they have been called "protective" molecules. C1q has a key role in the activation of the complement cascade and acts as a bridging molecule between apoptotic bodies and macrophages favouring phagocytosis. In addition to other functions, CRP, SAP and MBL bind to the surface of numerous pathogens as well as cellular debris and activate the complement cascade, thus stimulating their clearance by immune cells. The role of PTX3 is more controversial. In fact, PTX also promotes the clearance of microorganisms, but the activation of the complement cascade through C1q and removal of apoptotic material can be either stimulated or inhibited by this molecule. Antibodies against protective molecules have been recently reported in systemic lupus erythematosus and other autoimmune rheumatic diseases. Some of them seem to be pathogenetic and others protective. Thus, protective molecules and their cognate antibodies may constitute a regulatory network involved in autoimmunity. Dysregulation of this system might contribute to the development of autoimmune diseases in predisposed individuals.
Collapse
Affiliation(s)
- Margherita Zen
- Division of Rheumatology, Department of Clinical and Experimental Medicine, University of Padova, Padova, Italy
| | - Nicola Bassi
- Division of Rheumatology, Department of Clinical and Experimental Medicine, University of Padova, Padova, Italy
| | - Carla Campana
- Division of Rheumatology, Department of Clinical and Experimental Medicine, University of Padova, Padova, Italy
| | - Silvano Bettio
- Division of Rheumatology, Department of Clinical and Experimental Medicine, University of Padova, Padova, Italy
| | - Elena Tarricone
- Division of Rheumatology, Department of Clinical and Experimental Medicine, University of Padova, Padova, Italy
| | - Linda Nalotto
- Division of Rheumatology, Department of Clinical and Experimental Medicine, University of Padova, Padova, Italy
| | - Anna Ghirardello
- Division of Rheumatology, Department of Clinical and Experimental Medicine, University of Padova, Padova, Italy
| | - Andrea Doria
- Division of Rheumatology, Department of Clinical and Experimental Medicine, University of Padova, Padova, Italy
| |
Collapse
|
19
|
Comparison of three anti-CCP antibody tests and rheumatoid factor in RA and control patients. Clin Rev Allergy Immunol 2009; 34:21-5. [PMID: 18270853 DOI: 10.1007/s12016-007-8030-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
UNLABELLED It was the aim of this study to compare the diagnostic properties of two second generation anti-CCP antibodies assays (Quanta Lite CCP, Inova and EliA CCP, Phadia) with an assay containing a new antigen mixture (Quanta Lite CCP 3, Inova) and RF IgM. METHODS Sera from 86 RA patients and 90 control patients with other diseases, such as infections, connective tissue diseases, or other rheumatic diseases, were analysed using the four different methods. Specificity (84.4%) and PPV (80.3%) were lowest for RF IgM and highest for EliA CCP (specificity 97.8%, PPV 96.7%), the other values being close to those of EliA CCP. Sensitivity was highest for Quanta Lite CCP (73.3%). Efficiency was highest for Quanta Lite CCP (84.1%) at the lower cut off followed by EliA CCP at both cut offs (83.0%). The discrimination between RA sera (mean value 407.67 U/ml) and control sera (4.54 U/ml) and the relative risk (23.34) were best for EliA CCP. The results of this study reveal that there was no advantage of the anti-CCP antibodies assay applying a new antigen mixture (Quanta Lite CCP 3 ELISA) compared to two second generation anti-CCP antibodies assays (Quanta Lite CCP ELISA and EliA CCP).
Collapse
|
20
|
Bone marrow transplantation, refractory autoimmunity and the contributions of Susumu Ikehara. J Autoimmun 2008; 30:105-7. [PMID: 18243658 DOI: 10.1016/j.jaut.2007.12.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
21
|
Gupta B, Raghav SK, Das HR. S-Nitrosylation of mannose binding lectin regulates its functional activities and the formation of autoantibody in rheumatoid arthritis. Nitric Oxide 2008; 18:266-73. [DOI: 10.1016/j.niox.2008.01.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Revised: 01/11/2008] [Accepted: 01/23/2008] [Indexed: 11/27/2022]
|
22
|
Deane S, Meyers FJ, Gershwin ME. On reversing the persistence of memory: Hematopoietic stem cell transplant for autoimmune disease in the first ten years. J Autoimmun 2008; 30:180-96. [DOI: 10.1016/j.jaut.2007.12.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
23
|
Mannose-binding lectin deficiency is associated with early onset of polyarticular juvenile rheumatoid arthritis: a cohort study. Arthritis Res Ther 2008; 10:R32. [PMID: 18334024 PMCID: PMC2453777 DOI: 10.1186/ar2386] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2007] [Revised: 02/29/2008] [Accepted: 03/11/2008] [Indexed: 12/26/2022] Open
Abstract
Background Mannose-binding lectin (MBL) is an innate immune protein. The aim of our study was to determine whether genetically determined MBL deficiency is associated with susceptibility to juvenile rheumatoid arthritis (JRA) and whether MBL2 genotypes are associated with JRA severity. Methods In a retrospective cohort study of 218 patients with polyarthritis (n = 67) and oligoarthritis (n = 151), clinical and laboratory disease variables were obtained by clinical examination and chart reviews. Healthy Caucasian adults (n = 194) served as control individuals. MBL2 gene mutations were determined by Taqman analysis to identify genotypes with high, medium and low expression of MBL. Functional MBL plasma concentrations were measured using enzyme-linked immunosorbent assay. Associations between clinical and laboratory variables and MBL2 genotypes were determined by Kruskal-Wallis and χ2 tests. Results MBL2 genotype frequencies were similar in polyarthritis and oligoarthritis patients as compared with control individuals. MBL plasma concentrations were associated with the high, medium and low MBL genotype expression groups (P < 0.01). In polyarthritis patients, the presence of low-expressing (deficient) MBL2 genotypes was associated with early age at onset of disease (P = 0.03). In oligoarthritis patients, patients with low-expressing MBL2 genotypes were more often in remission (81%) than patients in the medium (54%) and high (56%) genotype groups (P = 0.02). The remaining clinical and laboratory variables, such as arthritis severity index, presence of radiographic erosions and antinuclear antibody positivity, were not associated with MBL2 genotypes. Conclusion Genetically determined MBL deficiency does not increase susceptibility to JRA, but MBL deficiency is associated with a younger age at onset of juvenile polyarthritis. On the other hand, MBL-deficient children with juvenile oligoarthritis are more often in remission. Therefore, MBL appears to play a dual role in JRA.
Collapse
|
24
|
Abstract
The recent development in the authors' laboratory of a sensitive bead assay able to detect AMA in 20% of otherwise AMA-negative sera seems to support the hypothesis that many AMA-negative cases of primary biliary cirrhosis (PCB) are secondary to limits in the methods used and do not represent an independent clinical entity. Clinical data demonstrate that patients without detectable serum AMA do not differ in their natural history from their seropositive counterparts. Anti-nuclear antibodies have been associated repeatedly with more severe disease and are helpful tools in the management of patients who have PBC, particularly those lacking AMA.
Collapse
|
25
|
Abstract
In April 2007, an international Colloquium bridging scientific and clinical disciplines was held to discuss the role of cellular and tissue damage in the initiation, development and persistence of autoimmune disease. Five potential etiologic and pathophysiologic processes fundamental to autoimmune disease (i.e. inflammation, infection, apoptosis, environmental exposure and genetics) were the focus of the presentations and integrative discussions at the Colloquium. The information presented on these topics is condensed in this review. Inflammation has close clinico-pathologic associations with autoimmunity, but future analyses will require better definition and metrics of inflammation, particularly for the earliest cellular and molecular components dependent on recruitment of elements of innate immunity. Although infection may be associated with increased levels of autoantibodies, most infections and virtually all vaccinations in humans lack well-established links to autoimmune diseases. Further application of well-designed, long-term epidemiologic and population-based studies is urgently needed to relate antecedent exposures with later occurring stigmata of autoimmunity with a goal of discerning potentially susceptible individuals or subpopulations. Suspect infections requiring closer interrogation include EB virus (SLE and other diseases), HCV (autoimmune hepatitis), beta hemolytic streptococci (rheumatic carditis) and Helicobacter pylori (autoimmune gastritis) among others. And even if a micro-organism was to be incriminated, mechanisms of initiation/perpetuation of autoimmunity continue to challenge investigators. Plausible mechanisms include potentiation and diversion of innate immunity; exposure or spillage of intracellular autoantigens; or provision of autoantigenic mimics. Integrity of apoptosis as a critical safeguard against autoimmunity was discussed in the contexts of over-reactivity causing autoantigens to gain enhanced exposure to the immune system, or under-reactivity producing insufficient elimination of autoreactive clones of lymphocytes. Although environmental agents are widely believed to serve as necessary "triggers" of autoimmune disease in genetically predisposed individuals, only a few such agents (mainly drugs and some nutrients) have been clearly identified and their mechanism of action defined. Finally an essential genetic foundation underlies all these hazards for autoimmunity in the form of risk-associated polymorphisms in immunoregulatory genes. They may be predictive of future or impending disease.
Collapse
Affiliation(s)
- Ian R Mackay
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | | | | |
Collapse
|
26
|
Sharma P, Gupta B, Farhat Basir S, Rani Das H, Nahar P. Rapid and sensitive detection of autoantibody in rheumatoid arthritis patients by heat-mediated ELISA. Clin Biochem 2008; 41:97-102. [DOI: 10.1016/j.clinbiochem.2007.09.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2007] [Revised: 09/12/2007] [Accepted: 09/28/2007] [Indexed: 11/16/2022]
|
27
|
Cutolo M, Straub RH. Circadian rhythms in arthritis: Hormonal effects on the immune/inflammatory reaction. Autoimmun Rev 2008; 7:223-8. [DOI: 10.1016/j.autrev.2007.11.019] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
28
|
|
29
|
Matsuura E, Kobayashi K, Lopez LR. Preventing autoimmune and infection triggered atherosclerosis for an enduring healthful lifestyle. Autoimmun Rev 2008; 7:214-22. [DOI: 10.1016/j.autrev.2007.11.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
30
|
|
31
|
Sjöwall C, Wetterö J. Pathogenic implications for autoantibodies against C-reactive protein and other acute phase proteins. Clin Chim Acta 2007; 378:13-23. [PMID: 17239838 DOI: 10.1016/j.cca.2006.12.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Revised: 11/29/2006] [Accepted: 12/05/2006] [Indexed: 12/21/2022]
Abstract
Systemic lupus erythematosus (SLE) is a systemic rheumatic disease characterized clinically by multiorgan involvement and serologically by the occurrence of antinuclear antibodies. SLE patients may present with multiple autoantibodies to cytoplasmic and cell surface antigens as well as to circulating plasma proteins. Another feature of SLE is that serum levels of C-reactive protein (CRP) often remain low despite high disease activity and despite high levels of other acute phase proteins and interleukin-6, i.e. the main CRP inducing cytokine. Apart from its important role as a laboratory marker of inflammation, CRP attracts increasing interest due to its many intriguing biological functions, one of which is a role as an opsonin contributing to the elimination of apoptotic cell debris, e.g. nucleosomes, thereby preventing immunization against autoantigens. Recently, autoantibodies against CRP and other acute phase proteins have been reported in certain rheumatic conditions, including SLE. Although the presence of anti-CRP autoantibodies does not explain the failed CRP response in SLE, antibodies directed against acute phase proteins have several implications of pathogenetic interest. This paper thus highlights the biological and clinical aspects of native and monomeric CRP and anti-CRP, as well as autoantibodies against mannose-binding lectin, serum amyloid A and serum amyloid P component.
Collapse
Affiliation(s)
- Christopher Sjöwall
- Division of Rheumatology/Autoimmunity and Immune Regulation Unit (AIR), Department of Molecular and Clinical Medicine, Linköping University, SE-581 85 Linköping, Sweden.
| | | |
Collapse
|