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Wei SJ, Xiong Q, Yao H, He QM, Yu PL. Is systemic lupus erythematosus linked to Immunoglobulin G4 Autoantibodies? Hum Immunol 2024; 85:110826. [PMID: 38954949 DOI: 10.1016/j.humimm.2024.110826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 04/26/2024] [Accepted: 05/21/2024] [Indexed: 07/04/2024]
Abstract
Systemic lupus erythematosus (SLE) is a systemic autoimmune disorder characterized by a hyperactive immune system with multiple abnormalities in B-cell proliferation, antibody production, T-cell regulation, and immune complex (IC) formation. In humans, Immunoglobulin (Ig) G is found in four subclasses. IgG1-IgG4, which are distinguished by both structural and biological differences. Fab-arm Exchange (FAE), specific biases in the IgG4 response repertoire, and a decreased capacity to induce effector functions mediated by interactions in the fragment crystallizable (Fc) region are just a few of the distinctive characteristics of IgG4. The recent finding of the presence of double-stranded DNA (dsDNA) and antinuclear antibody (ANA)-IgG4 has raised attention to this IgG subclass and its possible role in SLE. IgG4 was previously believed to just have anti-inflammatory effects by inhibiting immune responses, but recent studies have shown that these antibodies can also play a role in the onset and development of some clinical disorders. To consider the clinical effects of IgG4 presence, it is necessary to discuss its characteristics, which could underlie the potential role it can play in SLE. Therefore, this study aimed to comprehensively review the role of IgG4 in SLE to elucidate the collective incidence of high IgG4 levels reported in some SLE patients.
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Affiliation(s)
- Shu-Jun Wei
- Sichuan Police College, Longtouguan Road, Jiangyang District, Luzhou City, Sichuan Province, China
| | - Qian Xiong
- Chongqing Key Laboratory of Development and Utilization of Genuine Medicinal Materials in Three Gorges Reservoir Area, Chongqing Three Gorges Medical College, China
| | - Huan Yao
- Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, Sichuan, China; Sichuan Provincial Engineering Research Center of Innovative Re-development of Famous Classical Formulas, Pengzhou 611930, China
| | - Qing-Man He
- Affiliated Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Peng-Long Yu
- Chongqing Key Laboratory of Development and Utilization of Genuine Medicinal Materials in Three Gorges Reservoir Area, Chongqing Three Gorges Medical College, China.
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2
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Stork EM, van Rijswijck DMH, van Schie KA, Hoek M, Kissel T, Scherer HU, Huizinga TWJ, Heck AJR, Toes REM, Bondt A. Antigen-specific Fab profiling achieves molecular-resolution analysis of human autoantibody repertoires in rheumatoid arthritis. Nat Commun 2024; 15:3114. [PMID: 38600082 PMCID: PMC11006680 DOI: 10.1038/s41467-024-47337-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 03/25/2024] [Indexed: 04/12/2024] Open
Abstract
The presence of autoantibodies is a defining feature of many autoimmune diseases. The number of unique autoantibody clones is conceivably limited by immune tolerance mechanisms, but unknown due to limitations of the currently applied technologies. Here, we introduce an autoantigen-specific liquid chromatography-mass spectrometry-based IgG1 Fab profiling approach using the anti-citrullinated protein antibody (ACPA) repertoire in rheumatoid arthritis (RA) as an example. We show that each patient harbors a unique and diverse ACPA IgG1 repertoire dominated by only a few antibody clones. In contrast to the total plasma IgG1 antibody repertoire, the ACPA IgG1 sub-repertoire is characterised by an expansion of antibodies that harbor one, two or even more Fab glycans, and different glycovariants of the same clone can be detected. Together, our data indicate that the autoantibody response in a prominent human autoimmune disease is complex, unique to each patient and dominated by a relatively low number of clones.
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Affiliation(s)
- Eva Maria Stork
- Department of Rheumatology, Leiden University Medical Center, Albinusdreef 2, Leiden, The Netherlands
| | - Danique M H van Rijswijck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht, The Netherlands
- Netherlands Proteomics Center, Padualaan 8, Utrecht, the Netherlands
| | - Karin A van Schie
- Department of Rheumatology, Leiden University Medical Center, Albinusdreef 2, Leiden, The Netherlands
| | - Max Hoek
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht, The Netherlands
- Netherlands Proteomics Center, Padualaan 8, Utrecht, the Netherlands
| | - Theresa Kissel
- Department of Rheumatology, Leiden University Medical Center, Albinusdreef 2, Leiden, The Netherlands
| | - Hans Ulrich Scherer
- Department of Rheumatology, Leiden University Medical Center, Albinusdreef 2, Leiden, The Netherlands
| | - Tom W J Huizinga
- Department of Rheumatology, Leiden University Medical Center, Albinusdreef 2, Leiden, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht, The Netherlands
- Netherlands Proteomics Center, Padualaan 8, Utrecht, the Netherlands
| | - Rene E M Toes
- Department of Rheumatology, Leiden University Medical Center, Albinusdreef 2, Leiden, The Netherlands
| | - Albert Bondt
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht, The Netherlands.
- Netherlands Proteomics Center, Padualaan 8, Utrecht, the Netherlands.
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Wang J, Lundström SL, Lu W, Huang Y, Rodin S, Zubarev RA. SpotLight proteomics identifies variable sequences of blood antibodies specific against deamidated human serum albumin. Mol Cell Proteomics 2023:100589. [PMID: 37301377 PMCID: PMC10345337 DOI: 10.1016/j.mcpro.2023.100589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 05/23/2023] [Accepted: 06/07/2023] [Indexed: 06/12/2023] Open
Abstract
Spontaneous deamidation of asparaginyl residues in proteins, if not repaired or cleared, can set in motion a cascade that leads to deteriorated health. Previously, we have discovered that deamidated human serum albumin (HSA) is elevated in blood of patients with Alzheimer's disease and other neurodegenerative diseases, while the level of endogenous antibodies against deamidated HSA is significantly diminished, creating an imbalance between the risk factor and the defense against it. Endogenous antibodies against deamidated proteins are still unexplored. In the current study, we employed the SpotLight proteomics approach to identify novel amino acid sequences in antibodies specific to deamidated HSA. The results provide new insights into the clearance mechanism of deamidated proteins, a possible avenue for prevention of neurodegeneration.
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Affiliation(s)
- Jijing Wang
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17 165 Stockholm, Sweden
| | - Susanna L Lundström
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17 165 Stockholm, Sweden
| | - Weiqi Lu
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17 165 Stockholm, Sweden; Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Yiqi Huang
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17 165 Stockholm, Sweden; Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Sergey Rodin
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17 165 Stockholm, Sweden; Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - Roman A Zubarev
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17 165 Stockholm, Sweden.
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Differences in IgG autoantibody Fab glycosylation across autoimmune diseases. J Allergy Clin Immunol 2023:S0091-6749(23)00091-X. [PMID: 36716825 DOI: 10.1016/j.jaci.2022.10.035] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 10/12/2022] [Accepted: 10/14/2022] [Indexed: 01/29/2023]
Abstract
BACKGROUND Increased prevalence of autoantibody Fab glycosylation has been demonstrated for several autoimmune diseases. OBJECTIVES To study whether elevated Fab glycosylation is a common feature of autoimmunity, this study investigated Fab glycosylation levels on serum IgG and its subclasses for autoantibodies associated with a range of different B cell-mediated autoimmune diseases, including rheumatoid arthritis, myasthenia gravis subtypes, pemphigus vulgaris, antineutrophil cytoplasmic antibody-associated vasculitis, systemic lupus erythematosus, anti-glomerular basement membrane glomerulonephritis, thrombotic thrombocytopenic purpura, and Guillain-Barré syndrome. METHODS The level of Fab glycosylated IgG antibodies was assessed by lectin affinity chromatography and autoantigen-specific immunoassays. RESULTS In 6 of 10 autoantibody responses, in 5 of 8 diseases, the investigators found increased levels of Fab glycosylation on IgG autoantibodies that varied from 86% in rheumatoid arthritis to 26% in systemic lupus erythematosus. Elevated autoantibody Fab glycosylation was not restricted to IgG4, which is known to be prone to Fab glycosylation, but was also present in IgG1. When autoimmune diseases with a chronic disease course were compared with more acute autoimmune illnesses, increased Fab glycosylation was restricted to the chronic diseases. As a proxy for chronic autoantigen exposure, the investigators determined Fab glycosylation levels on antibodies to common latent herpes viruses, as well as to glycoprotein 120 in individuals who are chronically HIV-1-infected. Immunity to these viral antigens was not associated with increased Fab glycosylation levels, indicating that chronic antigen-stimulation as such does not lead to increased Fab glycosylation levels. CONCLUSIONS These data indicate that in chronic but not acute B cell-mediated autoimmune diseases, disease-specific autoantibodies are enriched for Fab glycans.
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Treger RS, Fink SL. Beyond Titer: Expanding the Scope of Clinical Autoantibody Testing. J Appl Lab Med 2022; 7:99-113. [DOI: 10.1093/jalm/jfab123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 09/17/2021] [Indexed: 11/14/2022]
Abstract
Abstract
Background
Autoantibodies that bind self-antigens are a hallmark of autoimmune diseases, but can also be present in healthy individuals. Clinical assays that detect and titer antigen-specific autoantibodies are an important component of the diagnosis and monitoring of autoimmune diseases. Autoantibodies may contribute to disease pathogenesis via effector functions that are dictated by both the antigen-binding site and constant domain.
Content
In this review, we discuss features of antibodies, in addition to antigen-binding specificity, which determine effector function. These features include class, subclass, allotype, and glycosylation. We discuss emerging data indicating that analysis of these antibody features may be informative for diagnosis and monitoring of autoimmune diseases. We also consider methodologies to interrogate these features and consider how they could be implemented in the clinical laboratory.
Summary
Future autoantibody assays may incorporate assessment of additional antibody features that contribute to autoimmune disease pathogenesis and provide added clinical value.
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Affiliation(s)
- Rebecca S Treger
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Susan L Fink
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
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He J, Ju J, Wang X. The current status of anti-citrullinated protein antibodies and citrullinated protein-reactive B cells in the pathogenesis of rheumatoid arthritis. Mol Biol Rep 2021; 49:2475-2485. [PMID: 34855107 DOI: 10.1007/s11033-021-07034-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Accepted: 11/26/2021] [Indexed: 11/26/2022]
Abstract
Anti-citrullinated protein antibodies are a hallmark of rheumatoid arthritis. It is widely acknowledged that the presence of ACPAs is the result of the interaction of genes, the environment and epigenetic modifications. The mechanism by which the factors, especially citrullination and ACPA glycosylation, affect ACPAs is still unclear. In this article, we review the presence of the ACPAs in RA and their relationship with clinical manifestations. The pathogenicity of ACPAs and B cells in RA was also summarized. A growing body of evidence has shown that ACPA-positive patients have more serious bone erosion and destruction and poor clinical prognosis than ACPA-negative patients. Recently, with the direct study of citrullinated protein-reactive B cells, their role in the development of rheumatoid arthritis has been further understood. It indicates that further understanding of the mechanism of ACPAs and CP-reactive B cells would beneficial in the prevention and treatment of RA.
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Affiliation(s)
- Jia He
- School of Clinical Medicine, Weifang Medical University, Weifang, China
| | - JiYu Ju
- Department of Immunology, Weifang Medical University, Weifang, China
| | - XiaoDong Wang
- Department of Rheumatology and Immunology, Affiliated Hospital of Weifang Medical University, Weifang, China.
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Impact of Posttranslational Modification in Pathogenesis of Rheumatoid Arthritis: Focusing on Citrullination, Carbamylation, and Acetylation. Int J Mol Sci 2021; 22:ijms221910576. [PMID: 34638916 PMCID: PMC8508717 DOI: 10.3390/ijms221910576] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 09/23/2021] [Accepted: 09/26/2021] [Indexed: 12/24/2022] Open
Abstract
Rheumatoid arthritis (RA) is caused by prolonged periodic interactions between genetic, environmental, and immunologic factors. Posttranslational modifications (PTMs) such as citrullination, carbamylation, and acetylation are correlated with the pathogenesis of RA. PTM and cell death mechanisms such as apoptosis, autophagy, NETosis, leukotoxic hypercitrullination (LTH), and necrosis are related to each other and induce autoantigenicity. Certain microbial infections, such as those caused by Porphyromonasgingivalis, Aggregatibacter actinomycetemcomitans, and Prevotella copri, can induce autoantigens in RA. Anti-modified protein antibodies (AMPA) containing anti-citrullinated protein/peptide antibodies (ACPAs), anti-carbamylated protein (anti-CarP) antibodies, and anti-acetylated protein antibodies (AAPAs) play a role in pathogenesis as well as in prediction, diagnosis, and prognosis. Interestingly, smoking is correlated with both PTMs and AMPAs in the development of RA. However, there is lack of evidence that smoking induces the generation of AMPAs.
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Koneczny I. Update on IgG4-mediated autoimmune diseases: New insights and new family members. Autoimmun Rev 2020; 19:102646. [PMID: 32801046 DOI: 10.1016/j.autrev.2020.102646] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 03/08/2020] [Indexed: 12/23/2022]
Abstract
Antibodies of IgG4 subclass are exceptional players of the immune system, as they are considered to be immunologically inert and functionally monovalent, and as such may be part of classical tolerance mechanisms. IgG4 antibodies are found in a range of different diseases, including IgG4-related diseases, allergy, cancer, rheumatoid arthritis, helminth infection and IgG4 autoimmune diseases, where they may be pathogenic or protective. IgG4 autoimmune diseases are an emerging new group of diseases that are characterized by pathogenic, antigen-specific autoantibodies of IgG4 subclass, such as MuSK myasthenia gravis, pemphigus vulgaris and thrombotic thrombocytopenic purpura. The list of IgG4 autoantigens is rapidly growing and to date contains 29 candidate antigens. Interestingly, IgG4 autoimmune diseases are restricted to four distinct organs: 1) the central and peripheral nervous system, 2) the kidney, 3) the skin and mucous membranes and 4) the vascular system and soluble antigens in the blood circulation. The pathogenicity of IgG4 can be validated using our classification system, and is usually excerted by functional blocking of protein-protein interaction.
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Affiliation(s)
- Inga Koneczny
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria.
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Thiagarajan D, Fiskesund R, Frostegård A, Steen J, Rahman M, Vikström M, Lundström S, Frostegård J. Immunoglobulin G1 Antibodies Against Phosphorylcholine Are Associated With Protection in Systemic Lupus Erythematosus and Atherosclerosis: Potential Underlying Mechanisms. ACR Open Rheumatol 2020; 2:344-356. [PMID: 32392632 PMCID: PMC7301871 DOI: 10.1002/acr2.11127] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 02/10/2020] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE Immunoglobulin M antibodies against phosphorylcholine (anti-PCs) may be protective in atherosclerosis, cardiovascular disease (CVD), and systemic lupus erythematosus (SLE). We study immunoglobulin G1 (IgG1) and immunoglobulin G2 (IgG2) anti-PCs, with a focus on atherosclerosis and SLE. METHODS We determined anti-PCs by using the enzyme-linked immunosorbent assay in 116 patients with SLE and 110 age- and sex-matched controls. For functional studies, we used three in-house-generated, fully human monoclonal IgG1 anti-PCs (A01, D05, and E01). Apoptosis was induced in Jurkat T cells and preincubated with A01, D05, E01, or IgG1 isotype control, and effects on efferocytosis by human macrophages were studied. Anti-PC peptide/protein characterization was determined using a proteomics de novo sequencing approach. RESULTS IgG1, but not IgG2, anti-PC levels were higher among patients with SLE (P = 0.02). IgG1 anti-PCs were negatively associated with Systemic Lupus International Collaborating Clinics (SLICC) damage index and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores (odds ratio [OR]: 2.978 [confidence interval (CI): 0.876-10.098] and OR: 5.108 [CI 1.3-20.067], respectively) and negatively associated with CVD, atherosclerotic plaques, and echolucent plaques (potentially vulnerable plaques), but the association for the two former was not significant after controlling for confounders. D05 had a maximum effect on macrophage efferocytosis efficiency, followed by A01 and E01. The monoclonal antibodies showed differential binding specificity to PC and PC-associated neoepitopes. A peptide analysis showed a difference in the complementarity-determining region 3 of the three IgG1 anti-PC clones that are crucial for recognition of PC on apoptotic cell surfaces and other neoepitopes. CONCLUSION IgG1 anti-PCs are negatively associated with disease activity and disease damage in SLE, but the negative association with CVD is also dependent on confounding risk factors. One potential underlying mechanism could be increased clearance of dead cells.
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Affiliation(s)
| | - R Fiskesund
- Karolinska University Hospital, Huddinge, Sweden
| | | | - J Steen
- Karolinska Institutet, Stockholm, Sweden
| | - M Rahman
- Karolinska Institutet, Stockholm, Sweden
| | - M Vikström
- Karolinska Institutet, Stockholm, Sweden
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Autoantibodies as Diagnostic Markers and Mediator of Joint Inflammation in Arthritis. Mediators Inflamm 2019; 2019:6363086. [PMID: 31772505 PMCID: PMC6854956 DOI: 10.1155/2019/6363086] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 09/14/2019] [Indexed: 12/11/2022] Open
Abstract
Rheumatoid arthritis is a systemic, polygenic, and multifactorial syndrome characterized by erosive polyarthritis, damage to joint architecture, and presence of autoantibodies against several self-structures in the serum and synovial fluid. These autoantibodies (anticitrullinated protein/peptide antibodies (ACPAs), rheumatoid factors (RF), anticollagen type II antibodies, antiglucose-6 phosphate isomerase antibodies, anticarbamylated protein antibodies, and antiacetylated protein antibodies) have different characteristics, diagnostic/prognostic value, and pathological significance in RA patients. Some of these antibodies are present in the patients' serum several years before the onset of clinical disease. Various genetic and environmental factors are associated with autoantibody production against different autoantigenic targets. Both the activating and inhibitory FcγRs and the activation of different complement cascades contribute to the downstream effector functions in the antibody-mediated disease pathology. Interplay between several molecules (cytokines, chemokines, proteases, and inflammatory mediators) culminates in causing damage to the articular cartilage and bones. In addition, autoantibodies are proven to be useful disease markers for RA, and different diagnostic tools are being developed for early diagnosis of the clinical disease. Recently, a direct link was proposed between the presence of autoantibodies and bone erosion as well as in the induction of pain. In this review, the diagnostic value of autoantibodies, their synthesis and function as a mediator of joint inflammation, and the significance of IgG-Fc glycosylation are discussed.
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Lundström SL, Heyder T, Wiklundh E, Zhang B, Eklund A, Grunewald J, Zubarev RA. SpotLight Proteomics-A IgG-Enrichment Phenotype Profiling Approach with Clinical Implications. Int J Mol Sci 2019; 20:ijms20092157. [PMID: 31052352 PMCID: PMC6540603 DOI: 10.3390/ijms20092157] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 04/18/2019] [Accepted: 04/25/2019] [Indexed: 12/13/2022] Open
Abstract
Sarcoidosis is a systemic interstitial lung disease of unknown aetiology. Less invasive diagnostics are needed to decipher disease pathology and to distinguish sub-phenotypes. Here we test if SpotLight proteomics, which combines de novo MS/MS sequencing of enriched IgG and co-extracted proteins with subsequent label-free quantification of new and known peptides, can differentiate controls and sarcoidosis phenotypes (Löfgrens and non-Löfgrens syndrome, LS and nonLS). Intra-individually matched IgG enriched from serum and bronchial lavage fluid (BALF) from controls (n = 12), LS (n = 11) and nonLS (n = 12) were investigated. High-resolution mass-spectrometry SpotLight proteomics and uni- and multivariate-statistical analyses were used for data processing. Major differences were particularly observed in control-BALF versus sarcoidosis-BALF. However, interestingly, information obtained from BALF profiles was still present (but less prominent) in matched serum profiles. By using information from orthogonal partial least squares discriminant analysis (OPLS-DA) differentiating 1) sarcoidosis-BALF and control-BALF and 2) LS-BALF vs. nonLS-BALF, control-serum and sarcoidosis-serum (p = 0.0007) as well as LS-serum and nonLS-serum (p = 0.006) could be distinguished. Noteworthy, many factors prominent in identifying controls and patients were those associated with Fc-regulation, but also features from the IgG-Fab region and novel peptide variants. Differences between phenotypes were mostly IgG-specificity related. The results support the analytical utility of SpotLight proteomics which prospectively have potential to differentiate closely related phenotypes from a simple blood test.
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Affiliation(s)
- Susanna L Lundström
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden.
| | - Tina Heyder
- Respiratory Medicine Unit, Department of Medicine Solna & Centre for Molecular Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden.
| | - Emil Wiklundh
- Respiratory Medicine Unit, Department of Medicine Solna & Centre for Molecular Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden.
| | - Bo Zhang
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden.
| | - Anders Eklund
- Respiratory Medicine Unit, Department of Medicine Solna & Centre for Molecular Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden.
| | - Johan Grunewald
- Respiratory Medicine Unit, Department of Medicine Solna & Centre for Molecular Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden.
| | - Roman A Zubarev
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden.
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Peffers MJ, Smagul A, Anderson JR. Proteomic analysis of synovial fluid: current and potential uses to improve clinical outcomes. Expert Rev Proteomics 2019; 16:287-302. [PMID: 30793992 DOI: 10.1080/14789450.2019.1578214] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Synovial fluid (SF) is in close proximity to tissues which are primarily altered during articular disease and has significant potential to better understand the underlying disease pathogeneses of articular pathologies and biomarker discovery. Although development of mass spectrometry-based methods has allowed faster and higher sensitivity techniques, interrogation of the SF proteome has been hindered by its large protein concentration dynamic range, impeding quantification of lower abundant proteins. Areas covered: Recent advances have developed methodologies to reduce the large protein concentration dynamic range of SF and subsequently allow deeper exploration of the SF proteome. This review concentrates on methods to overcome biofluid complexity, mass spectrometry proteomics methodologies, extracellular vesicles proteomics and the application of advances within the field in clinical disease, including osteoarthritis, rheumatoid arthritis, spondyloarthritis and juvenile arthritis. A narrative review was conducted with articles searched using PubMed, 1991-2018. Expert opinion: The SF proteomics field faces various challenges, including the requirement for rigorous and standardised methods of sample collection/storage, the sensitivity and specificity of proteomic assays, techniques to combat the large protein concentration dynamic range and comprehensive data analysis to reduce falsely identified markers. Additionally, there are challenges in developing multi 'omic' integration techniques, with computational integration enhancing analysis.
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Affiliation(s)
- Mandy Jayne Peffers
- a Comparative Musculoskeletal Biology, Institute of Ageing and Chronic Disease , University of Liverpool , Liverpool , UK
| | - Aibek Smagul
- a Comparative Musculoskeletal Biology, Institute of Ageing and Chronic Disease , University of Liverpool , Liverpool , UK
| | - James Ross Anderson
- a Comparative Musculoskeletal Biology, Institute of Ageing and Chronic Disease , University of Liverpool , Liverpool , UK
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Patients with anti-Jo1 antibodies display a characteristic IgG Fc-glycan profile which is further enhanced in anti-Jo1 autoantibodies. Sci Rep 2018; 8:17958. [PMID: 30560888 PMCID: PMC6298993 DOI: 10.1038/s41598-018-36395-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 11/19/2018] [Indexed: 01/27/2023] Open
Abstract
IgG Fc-glycans affect IgG function and are altered in autoimmune diseases and autoantibodies. Anti-histidyl tRNA synthetase autoantibodies (anti-Jo1) are frequent in patients with idiopathic inflammatory myopathies (IIM) and anti-synthetase syndrome (ASS) with associated interstitial lung disease (ILD). Thus, we hypothesized that the total-IgG Fc-glycans from Jo1+ versus Jo1− patients and anti-Jo1-IgG would show characteristic differences, and that particular Fc-glycan features would be associated with specific clinical manifestations. By proteomics based mass spectrometry we observed a high abundance of agalactosylated IgG1 Fc-glycans in ASS/IIM patients (n = 44) compared to healthy age matched controls (n = 24). Using intra-individual normalization of the main agalactosylated glycan (FA2) of IgG1 vs FA2-IgG2, ASS/IIM and controls were distinguished with an area under the curve (AUC) of 79 ± 6%. For Jo1+ patients (n = 19) the AUCs went up to 88 ± 6%. Bisected and afucosylated Fc-glycans were significantly lower in Jo1+ compared to Jo1− patients. Anti-Jo1-IgG enriched from eleven patients contained even significantly lower abundances of bisected, afucosylated and galactosylated forms compared to matched total-IgG. ASS and ILD diagnosis, as well as lysozyme and thrombospondin correlated with Jo1+ characteristic Fc-glycan features. These results suggest that the anti-Jo1+ patient Fc-glycan profile contains phenotype specific features which may underlie the pathogenic role of Jo1 autoantibodies.
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Heyder T, Wiklundh E, Eklund A, James A, Grunewald J, Zubarev RA, Lundström SL. Altered Fc galactosylation in IgG 4 is a potential serum marker for chronic lung disease. ERJ Open Res 2018; 4:00033-2018. [PMID: 30083550 PMCID: PMC6066530 DOI: 10.1183/23120541.00033-2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 04/27/2018] [Indexed: 12/24/2022] Open
Abstract
Characterising chronic lung diseases is challenging. New, less invasive diagnostics are needed to decipher disease pathologies and subphenotypes. Fc galactosylation is known to affect IgG function, and is altered in autoimmune disorders and under other pathological conditions. We tested how well Fc glycans in IgG from bronchoalveolar lavage fluid (BALF) and serum correlated, and if the Fc glycan profile could reveal pulmonary inflammation. A shotgun proteomics approach was used to profile Fc glycans in serum and BALF of controls (n=12) and sarcoidosis phenotypes (Löfgren's syndrome (LS), n=11; and non-LS, n=12). Results were further validated in severe asthma (SA) (n=20) and published rheumatoid arthritis (RA) patient data (n=13) including clinical information. Intra-individually, Fc-galactosylation status of IgG1 (R2=0.87) and IgG4 (R2=0.95) correlated well between matrixes. Following GlycoAge-index correction, the ratio between agalactosylated and digalactosylated Fc glycans of IgG4 could distinguish sarcoidosis and SA from healthy and RA subjects with a mean±se area under the curve (AUC) of 78±6%. The AUC increased to 83±6% using the more chronic lung disease types (non-LS and SA) and most strikingly, to 87±6% for the SA subgroup. The results indicate that the Fc galactosylation status of IgG4 is a potential blood test marker for chronic lung inflammation. IgG4 Fc galactosylation correlates between serum and BALF (R2=0.95) and is a potential blood marker for chronic lung inflammationhttp://ow.ly/XaNd30k35wg
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Affiliation(s)
- Tina Heyder
- Respiratory Medicine Unit, Dept of Medicine Solna and Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Division of Physiological Chemistry I, Dept of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Joint first authors
| | - Emil Wiklundh
- Respiratory Medicine Unit, Dept of Medicine Solna and Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Joint first authors
| | - Anders Eklund
- Respiratory Medicine Unit, Dept of Medicine Solna and Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Anna James
- Centre for Allergy Research, Karolinska Institute, Stockholm, Sweden.,Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Johan Grunewald
- Respiratory Medicine Unit, Dept of Medicine Solna and Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Roman A Zubarev
- Division of Physiological Chemistry I, Dept of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Joint last authors
| | - Susanna L Lundström
- Division of Physiological Chemistry I, Dept of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Joint last authors
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15
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Nandakumar KS, Collin M, Happonen KE, Lundström SL, Croxford AM, Xu B, Zubarev RA, Rowley MJ, Blom AM, Kjellman C, Holmdahl R. Streptococcal Endo-β- N-Acetylglucosaminidase Suppresses Antibody-Mediated Inflammation In Vivo. Front Immunol 2018; 9:1623. [PMID: 30061892 PMCID: PMC6054937 DOI: 10.3389/fimmu.2018.01623] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 07/02/2018] [Indexed: 12/19/2022] Open
Abstract
Endo-β-N-acetylglucosaminidase (EndoS) is a family 18 glycosyl hydrolase secreted by Streptococcus pyogenes. Recombinant EndoS hydrolyzes the β-1,4-di-N-acetylchitobiose core of the N-linked complex type glycan on the asparagine 297 of the γ-chains of IgG. Here, we report that EndoS and IgG hydrolyzed by EndoS induced suppression of local immune complex (IC)-mediated arthritis. A small amount (1 µg given i.v. to a mouse) of EndoS was sufficient to inhibit IgG-mediated arthritis in mice. The presence of EndoS disturbed larger IC lattice formation both in vitro and in vivo, as visualized with anti-C3b staining. Neither complement binding in vitro nor antigen-antibody binding per se were affected. Thus, EndoS could potentially be used for treating patients with IC-mediated pathology.
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Affiliation(s)
- Kutty Selva Nandakumar
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China.,Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Mattias Collin
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kaisa E Happonen
- Department of Translational Medicine, Lund University, Lund, Sweden.,Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Susanna L Lundström
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Allyson M Croxford
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Bingze Xu
- Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Roman A Zubarev
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Merrill J Rowley
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Anna M Blom
- Department of Translational Medicine, Lund University, Lund, Sweden
| | | | - Rikard Holmdahl
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China.,Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
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16
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Holers VM, Banda NK. Complement in the Initiation and Evolution of Rheumatoid Arthritis. Front Immunol 2018; 9:1057. [PMID: 29892280 PMCID: PMC5985368 DOI: 10.3389/fimmu.2018.01057] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 04/27/2018] [Indexed: 01/03/2023] Open
Abstract
The complement system is a major component of the immune system and plays a central role in many protective immune processes, including circulating immune complex processing and clearance, recognition of foreign antigens, modulation of humoral and cellular immunity, removal of apoptotic and dead cells, and engagement of injury resolving and tissue regeneration processes. In stark contrast to these beneficial roles, however, inadequately controlled complement activation underlies the pathogenesis of human inflammatory and autoimmune diseases, including rheumatoid arthritis (RA) where the cartilage, bone, and synovium are targeted. Recent studies of this disease have demonstrated that the autoimmune response evolves over time in an asymptomatic preclinical phase that is associated with mucosal inflammation. Notably, experimental models of this disease have demonstrated that each of the three major complement activation pathways plays an important role in recognition of injured joint tissue, although the lectin and amplification pathways exhibit particularly impactful roles in the initiation and amplification of damage. Herein, we review the complement system and focus on its multi-factorial role in human patients with RA and experimental murine models. This understanding will be important to the successful integration of the emerging complement therapeutics pipeline into clinical care for patients with RA.
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Affiliation(s)
| | - Nirmal K. Banda
- Division of Rheumatology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
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17
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Lloyd KA, Steen J, Amara K, Titcombe PJ, Israelsson L, Lundström SL, Zhou D, Zubarev RA, Reed E, Piccoli L, Gabay C, Lanzavecchia A, Baeten D, Lundberg K, Mueller DL, Klareskog L, Malmström V, Grönwall C. Variable domain N-linked glycosylation and negative surface charge are key features of monoclonal ACPA: Implications for B-cell selection. Eur J Immunol 2018. [PMID: 29512823 DOI: 10.1002/eji.201747446] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Autoreactive B cells have a central role in the pathogenesis of rheumatoid arthritis (RA), and recent findings have proposed that anti-citrullinated protein autoantibodies (ACPA) may be directly pathogenic. Herein, we demonstrate the frequency of variable-region glycosylation in single-cell cloned mAbs. A total of 14 ACPA mAbs were evaluated for predicted N-linked glycosylation motifs in silico, and compared to 452 highly-mutated mAbs from RA patients and controls. Variable region N-linked motifs (N-X-S/T) were strikingly prevalent within ACPA (100%) compared to somatically hypermutated (SHM) RA bone marrow plasma cells (21%), and synovial plasma cells from seropositive (39%) and seronegative RA (7%). When normalized for SHM, ACPA still had significantly higher frequency of N-linked motifs compared to all studied mAbs including highly mutated HIV broadly-neutralizing and malaria-associated mAbs. The Fab glycans of ACPA-mAbs were highly sialylated, contributed to altered charge, but did not influence antigen binding. The analysis revealed evidence of unusual B-cell selection pressure and SHM-mediated decrease in surface charge and isoelectric point in ACPA. It is still unknown how these distinct features of anti-citrulline immunity may have an impact on pathogenesis. However, it is evident that they offer selective advantages for ACPA+ B cells, possibly through non-antigen driven mechanisms.
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Affiliation(s)
- Katy A Lloyd
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Johanna Steen
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Khaled Amara
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Philip J Titcombe
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden.,The Center for Immunology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Lena Israelsson
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Susanna L Lundström
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Diana Zhou
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Roman A Zubarev
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Evan Reed
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Luca Piccoli
- Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland
| | - Cem Gabay
- Division of Rheumatology, University Hospitals of Geneva, Geneva, Switzerland
| | - Antonio Lanzavecchia
- Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland
| | - Dominique Baeten
- Department of Clinical Immunology and Rheumatology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Karin Lundberg
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Daniel L Mueller
- The Center for Immunology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Lars Klareskog
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Vivianne Malmström
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Caroline Grönwall
- Department of Medicine, Rheumatology Unit, Karolinska Institutet, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
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18
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Behrendt I, Prądzińska M, Spodzieja M, Czaplewska P, Kołodziejczyk AS, Szymańska A, Kasprzykowski F, Lundström SL, Zubarev RA, Rodziewicz-Motowidło S. Identification and characterization of antibodies elicited by human cystatin C fragment. J Mol Recognit 2017; 31. [PMID: 29205549 DOI: 10.1002/jmr.2689] [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: 09/26/2017] [Revised: 10/23/2017] [Accepted: 10/28/2017] [Indexed: 11/11/2022]
Abstract
Amyloid formation is associated with a number of neurodegenerative diseases that affect the independence and quality of life of aging populations. One of rather atypical, occurring at a young age amyloidosis is hereditary cystatin C amyloid angiopathy (HCCAA) related to aggregation of L68Q variant of human cystatin C (hCC). Human cystatin C plays a very important role in many aspects of human health; however, its amyloidogenic properties manifested in HCCAA present a real, lethal threat to some populations and any work on factors that can affect possible influencing hCC aggregation is not to overestimate. It was proved that interaction of hCC with monoclonal antibodies suppresses significantly hCC dimerization process. Therefore, immunotherapy seems to be the right approach toward possible HCCAA treatment. In this work, the hCC fragment encompassing residue 60-70 (in 2 variants: linear peptide and multiple antigenic peptide) was used as an immunogen in rabbit immunization. As a result, specific anti-hCC antibodies were found in both rabbit sera. Surprisingly, rabbit antibodies were obtained after immunization with only a short peptide. The obtained antibodies were characterized, and their influence on the aggregation propensity of the hCC molecules was evaluated. The antibodies turned out not to have any significant influence on the cystatin C dimerization process. Nevertheless, we hope that antibodies elicited in rabbits by other hCC fragments could lead to elaboration of effective treatment against HCCAA.
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Affiliation(s)
| | | | | | - Paulina Czaplewska
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Gdańsk, Poland
| | | | | | | | - Susanna L Lundström
- Department of Medical Biochemistry and Biophysics, Division of Physiological Chemistry, Karolinska Institutet, Stockholm, Sweden
| | - Roman A Zubarev
- Department of Medical Biochemistry and Biophysics, Division of Physiological Chemistry, Karolinska Institutet, Stockholm, Sweden
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19
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Kempers AC, Hafkenscheid L, Scherer HU, Toes REM. Variable domain glycosylation of ACPA-IgG: A missing link in the maturation of the ACPA response? Clin Immunol 2017; 186:34-37. [PMID: 28882619 DOI: 10.1016/j.clim.2017.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 09/03/2017] [Indexed: 12/14/2022]
Abstract
Anti-citrullinated Protein Antibodies (ACPA) are excellent markers for Rheumatoid arthritis (RA) and are postulated to have a pathogenic role in the disease process. A multistep model for the evolution of the ACPA response in RA was proposed in which an initial break of tolerance causes, as "first hit", "silent" production of ACPA without any clinical symptoms. The model further proposes that the ACPA immune response matures upon a certain (unknown) trigger, a "second hit", which leads to epitope spreading, an increase in ACPA titres and extended isotype usage before clinical RA manifestations. These occurrences are indicative of an expansion of the citrulline-specific B cell response, though ACPA remain of low avidity even in established disease. This persistence of low avidity is puzzling, as the typical signs of maturation of the immune response seem to be uncoupled from the classical process of affinity maturation. In fact, it suggests that B cells expressing ACPA could bypass selection mechanisms that otherwise control the expansion of auto-reactive B cells. In the established, chronic phase, we recently found that ACPA-IgG are extensively glycosylated in the variable (Fab) domain. More than 90% of ACPA-IgG molecules carry Fab glycans that are highly sialylated. This molecular feature is striking and may provide a missing link in our understanding of the maturation of the ACPA immune response. This review, therefore, describes the current knowledge about ACPA Fab glycosylation in the pathogenesis of RA.
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Affiliation(s)
- Ayla C Kempers
- Department of Rheumatology, Leiden University Medical Center, P.O. Box 9600, Leiden 2300 RC, The Netherlands.
| | - Lise Hafkenscheid
- Department of Rheumatology, Leiden University Medical Center, P.O. Box 9600, Leiden 2300 RC, The Netherlands.
| | - Hans Ulrich Scherer
- Department of Rheumatology, Leiden University Medical Center, P.O. Box 9600, Leiden 2300 RC, The Netherlands.
| | - René E M Toes
- Department of Rheumatology, Leiden University Medical Center, P.O. Box 9600, Leiden 2300 RC, The Netherlands.
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20
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Lundström SL, Hensvold AH, Rutishauser D, Klareskog L, Ytterberg AJ, Zubarev RA, Catrina AI. IgG Fc galactosylation predicts response to methotrexate in early rheumatoid arthritis. Arthritis Res Ther 2017; 19:182. [PMID: 28793911 PMCID: PMC5549282 DOI: 10.1186/s13075-017-1389-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 07/17/2017] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Methotrexate (MTX) is the standard first-line therapy in rheumatoid arthritis (RA) with variable clinical efficacy that is difficult to predict. The glycosylation status of immunoglobulin G (IgG) is altered in RA and influenced by MTX treatment. We aimed to further investigate if IgG glycosylation in untreated early RA can predict therapeutic response to MTX. METHODS We used a shotgun proteomic approach to screen for the Fc glycopeptides in the serum of 12 control subjects and 59 untreated patients with early RA prior to and following MTX initiation. MTX treatment response was defined according to the European League Against Rheumatism at a median of 14 weeks (range 13-15) after treatment initiation. Seropositive patients were defined as those testing positive for anticitrullinated protein antibodies and/or rheumatoid factor at baseline (n = 44). Data analysis was performed using uni- and multivariate statistics. RESULTS We could confirm a low abundance of galactosylated glycans in untreated patients with early RA compared with control subjects that was partially restored by MTX treatment. This was more evident among future nonresponders than among responders to MTX treatment. Results were further validated and confirmed by multivariate statistical analysis of the baseline Fc glycan, proteomic, and clinical data. We found that the ratio between the main agalactosylated (FA2) and main mono- and di-galactosylated Fc glycans (FA2G1 and FA2G2) of IgG1 ranked as the most prominent factor distinguishing responders from nonresponders. A low baseline ratio of FA2/[FA2G1 + FA2G2]-IgG1 was associated with nonresponse (OR 5.3 [1.6-17.0]) and was able to discriminate future nonresponders from responders to MTX therapy with a sensitivity of 70% (95% CI 46-88%) and a specificity of 69% (95% CI 52-83%). For seropositive patients (n = 44), this trend was improved with a sensitivity of 73% (95% CI 45-92%) for nonresponse and a specificity of 79% (95% CI 60-92%). CONCLUSIONS We show that the FA2/[FA2G1 + FA2G2] of IgG1 is a biomarker candidate that is significantly associated with nonresponding patients and has potential value for prediction of MTX clinical response.
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Affiliation(s)
- Susanna L Lundström
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Scheelesväg 2, SE 17177, Stockholm, Sweden.
| | - Aase H Hensvold
- Rheumatology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.,Rheumatology Unit, Karolinska University Hospital, Stockholm, Sweden
| | - Dorothea Rutishauser
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Scheelesväg 2, SE 17177, Stockholm, Sweden
| | - Lars Klareskog
- Rheumatology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.,Rheumatology Unit, Karolinska University Hospital, Stockholm, Sweden
| | - A Jimmy Ytterberg
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Scheelesväg 2, SE 17177, Stockholm, Sweden.,Rheumatology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Roman A Zubarev
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Scheelesväg 2, SE 17177, Stockholm, Sweden.
| | - Anca I Catrina
- Rheumatology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.,Rheumatology Unit, Karolinska University Hospital, Stockholm, Sweden
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21
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Lourido L, Blanco FJ, Ruiz-Romero C. Defining the proteomic landscape of rheumatoid arthritis: progress and prospective clinical applications. Expert Rev Proteomics 2017; 14:431-444. [PMID: 28425787 DOI: 10.1080/14789450.2017.1321481] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION The heterogeneity of Rheumatoid Arthritis (RA) and the absence of clinical tests accurate enough to identify the early stages of this disease have hampered its management. Therefore, proteomics research is increasingly focused on the discovery of novel biological markers, which would not only be able make an early diagnosis, but also to gain insight into the different pathological mechanisms underlying the heterogeneity of RA and also to stratify patients, which is critical to enabling effective treatments. Areas covered: The proteomic approaches that have been utilised to provide knowledge about RA pathogenesis, and to identify biomarkers for RA diagnosis, prognosis, disease monitoring and prediction of response to therapy, are summarized. Expert commentary: Although each proteomic study is unique in its design, all of them have contributed to the understanding of RA pathogenesis and the discovery of promising biomarkers for patient stratification, which would improve clinical care of RA patients. Still, efforts need to be made to validate these findings and translate them into clinical practice.
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Affiliation(s)
- Lucía Lourido
- a Rheumatology Division, ProteoRed/ISCIII Proteomics Group , INIBIC - Hospital Universitario de A Coruña , A Coruña , Spain.,b RIER-RED de Inflamación y Enfermedades Reumáticas , INIBIC-CHUAC , A Coruña , Spain
| | - Francisco J Blanco
- a Rheumatology Division, ProteoRed/ISCIII Proteomics Group , INIBIC - Hospital Universitario de A Coruña , A Coruña , Spain.,b RIER-RED de Inflamación y Enfermedades Reumáticas , INIBIC-CHUAC , A Coruña , Spain
| | - Cristina Ruiz-Romero
- a Rheumatology Division, ProteoRed/ISCIII Proteomics Group , INIBIC - Hospital Universitario de A Coruña , A Coruña , Spain.,c CIBER-BBN Instituto de Salud Carlos III , INIBIC-CHUAC , A Coruña , Spain
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22
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SpotLight Proteomics: uncovering the hidden blood proteome improves diagnostic power of proteomics. Sci Rep 2017; 7:41929. [PMID: 28167817 PMCID: PMC5294601 DOI: 10.1038/srep41929] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 01/05/2017] [Indexed: 01/25/2023] Open
Abstract
The human blood proteome is frequently assessed by protein abundance profiling using a combination of liquid chromatography and tandem mass spectrometry (LC-MS/MS). In traditional sequence database search, many good-quality MS/MS data remain unassigned. Here we uncover the hidden part of the blood proteome via novel SpotLight approach. This method combines de novo MS/MS sequencing of enriched antibodies and co-extracted proteins with subsequent label-free quantification of new and known peptides in both enriched and unfractionated samples. In a pilot study on differentiating early stages of Alzheimer’s disease (AD) from Dementia with Lewy Bodies (DLB), on peptide level the hidden proteome contributed almost as much information to patient stratification as the apparent proteome. Intriguingly, many of the new peptide sequences are attributable to antibody variable regions, and are potentially indicative of disease etiology. When the hidden and apparent proteomes are combined, the accuracy of differentiating AD (n = 97) and DLB (n = 47) increased from ≈85% to ≈95%. The low added burden of SpotLight proteome analysis makes it attractive for use in clinical settings.
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23
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The role of anticitrullinated protein antibodies in the early stages of rheumatoid arthritis. Curr Opin Rheumatol 2016; 28:275-81. [PMID: 26945334 DOI: 10.1097/bor.0000000000000277] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW This review provides an update on the recent discoveries on the role of anticitrullinated protein antibodies (ACPA) in early rheumatoid arthritis (RA). RECENT FINDINGS RA is characterized by an immune response against posttranslationally modified proteins, in particular citrullinated proteins. Recent studies have found that the ACPA response matures shortly before clinical disease manifests itself and is characterized by an increase in titre, isotype switching, antigen-recognition profile, and a change in the Fc-glycosylation pattern. To date, many citrullinated autoantigens have been identified and novel studies suggest that the human leucocyte antigen class II locus may directly influence the maturation of the ACPA response via antigen-specific T cells. Clinical studies have demonstrated that effective treatment of arthritis can lead to reduced ACPA levels or a change in composition of ACPA. In addition to ACPA, autoantibodies targeting other posttranslational modifications have been identified and may be associated with disease prognosis. SUMMARY Key studies have demonstrated that autoimmunity against citrullinated proteins is already present in preclinical RA and matures over time. Future studies are required to reveal whether autoantibodies and the B cells that produce them play a role in disease development or can function as biomarkers for disease maturation.
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24
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Hafkenscheid L, Bondt A, Scherer HU, Huizinga TWJ, Wuhrer M, Toes REM, Rombouts Y. Structural Analysis of Variable Domain Glycosylation of Anti-Citrullinated Protein Antibodies in Rheumatoid Arthritis Reveals the Presence of Highly Sialylated Glycans. Mol Cell Proteomics 2016; 16:278-287. [PMID: 27956708 DOI: 10.1074/mcp.m116.062919] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 11/16/2016] [Indexed: 11/06/2022] Open
Abstract
Recently, we showed the unexpectedly high abundance of N-linked glycans on the Fab-domain of Anti-Citrullinated Protein Antibodies (ACPA). As N-linked glycans can mediate a variety of biological functions, we now aimed at investigating the structural composition of the Fab-glycans of ACPA-IgG to better understand their mediated biological effects. ACPA-IgG and noncitrulline specific (control) IgG from plasma and/or synovial fluid of nine ACPA positive rheumatoid arthritis patients were affinity purified. The N-linked glycosylation of total, Fc and F(ab')2 fragments, as well as heavy and light chains of ACPA-IgG and control IgG were analyzed by UHPLC and MALDI-TOF mass spectrometry. The Fc-glycosylation of ACPA-IgG and IgG was analyzed at the glycopeptide level using LC-MS. The structural analyses revealed that ACPA-IgG molecules contain highly sialylated glycans in their Fab-domain. Importantly, Fab-glycans were estimated to be present on over 90% of ACPA-IgG, which is five times higher than in control IgG isolated from the same patients. This feature was more prominent on ACPA isolated from synovial fluid compared with peripheral blood. These observations provide the first evidence pointing to the ability of ACPA-IgG to mediate novel immunological activities, for example through binding specific lectins via hyper-sialylated Fab-glycans.
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Affiliation(s)
- Lise Hafkenscheid
- From the ‡Department of Rheumatology, Leiden University Medical Center, 2300 RC Leiden, the Netherlands;
| | - Albert Bondt
- From the ‡Department of Rheumatology, Leiden University Medical Center, 2300 RC Leiden, the Netherlands.,§Center for Proteomics and Metabolomics, Leiden University Medical Center, 2300 RC Leiden, the Netherlands
| | - Hans U Scherer
- From the ‡Department of Rheumatology, Leiden University Medical Center, 2300 RC Leiden, the Netherlands
| | - Tom W J Huizinga
- From the ‡Department of Rheumatology, Leiden University Medical Center, 2300 RC Leiden, the Netherlands
| | - Manfred Wuhrer
- §Center for Proteomics and Metabolomics, Leiden University Medical Center, 2300 RC Leiden, the Netherlands
| | - René E M Toes
- From the ‡Department of Rheumatology, Leiden University Medical Center, 2300 RC Leiden, the Netherlands
| | - Yoann Rombouts
- From the ‡Department of Rheumatology, Leiden University Medical Center, 2300 RC Leiden, the Netherlands.,§Center for Proteomics and Metabolomics, Leiden University Medical Center, 2300 RC Leiden, the Netherlands.,¶Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, France
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25
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Prądzińska M, Behrendt I, Spodzieja M, Kołodziejczyk AS, Rodziewicz-Motowidło S, Szymańska A, Lundström SL, Zubarev RA, Macur K, Czaplewska P. Isolation and characterization of autoantibodies against human cystatin C. Amino Acids 2016; 48:2501-2518. [PMID: 27277188 DOI: 10.1007/s00726-016-2271-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 06/02/2016] [Indexed: 11/26/2022]
Abstract
Hereditary cystatin C amyloid angiopathy (HCCAA) is a severe neurodegenerative disorder related to the point mutation in cystatin C gene resulting in human cystatin C (hCC) L68Q variant. One of the potential immunotherapeutic approaches to HCCAA treatment is based on naturally occurring antibodies against cystatin C. A recent growing interest in autoantibodies, especially in the context of neurodegenerative diseases, emerges from their potential use as valuable diagnostic markers and for controlling protein aggregation. In this work, we present characteristics of natural anti-hCC antibodies isolated from the IgG fraction of human serum by affinity chromatography. The electrophoresis (1-D and 2-D) results demonstrated that the isolated NAbs are a polyclonal mixture, but their electrophoretic properties did not allow to classify the new autoantibodies to any particular type of IgG. The Fc-glycan status of the studied autoantibodies was assessed using mass spectrometry analysis. For the isolated NAbs, the epitopic fragments in hCC sequence were identified by MS-assisted proteolytic excision of the immune complex and compared with the ones predicted theoretically. The knowledge of hCC fragments binding to NAbs and other ligands may contribute to the search for new diagnostic methods for amyloidosis of different types and the search for their treatment.
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Affiliation(s)
- Martyna Prądzińska
- Faculty of Chemistry, Department of Biomedical Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland
| | - Izabela Behrendt
- Faculty of Chemistry, Department of Biomedical Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland
| | - Marta Spodzieja
- Faculty of Chemistry, Department of Biomedical Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland
| | - Aleksandra S Kołodziejczyk
- Faculty of Chemistry, Department of Biomedical Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland
| | - Sylwia Rodziewicz-Motowidło
- Faculty of Chemistry, Department of Biomedical Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland
| | - Aneta Szymańska
- Faculty of Chemistry, Department of Biomedical Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland
| | - Susanna L Lundström
- Division of Chemistry I, Head Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Scheelesvag 2, SE 17177, Stockholm, Sweden
| | - Roman A Zubarev
- Division of Chemistry I, Head Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Scheelesvag 2, SE 17177, Stockholm, Sweden
| | - Katarzyna Macur
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Kładki 24, 80-822, Gdansk, Poland
| | - Paulina Czaplewska
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Kładki 24, 80-822, Gdansk, Poland.
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26
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Barnidge DR, Lundström SL, Zhang B, Dasari S, Murray DL, Zubarev RA. Subset of Kappa and Lambda Germline Sequences Result in Light Chains with a Higher Molecular Mass Phenotype. J Proteome Res 2015; 14:5283-90. [DOI: 10.1021/acs.jproteome.5b00711] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Susanna L. Lundström
- Department of Medical Biochemistry & Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Bo Zhang
- Department of Medical Biochemistry & Biophysics, Karolinska Institutet, Stockholm, Sweden
| | | | | | - Roman A. Zubarev
- Department of Medical Biochemistry & Biophysics, Karolinska Institutet, Stockholm, Sweden
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27
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Iadarola P, Fumagalli M, Bardoni AM, Salvini R, Viglio S. Recent applications of CE- and HPLC-MS in the analysis of human fluids. Electrophoresis 2015; 37:212-30. [PMID: 26426542 DOI: 10.1002/elps.201500272] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 09/06/2015] [Accepted: 09/11/2015] [Indexed: 01/08/2023]
Abstract
The present review intends to cover the literature on the use of CE-/LC-MS for the analysis of human fluids, from 2010 until present. It has been planned to provide an overview of the most recent practical applications of these techniques to less extensively used human body fluids, including, bronchoalveolar lavage fluid, synovial fluid, nipple aspirate, tear fluid, breast fluid, amniotic fluid, and cerumen. Potential pitfalls related to fluid collection and sample preparation, with particular attention to sample clean-up procedures, and methods of analysis, from the research laboratory to a clinical setting will also be addressed. While being apparent that proteomics/metabolomics represent the most prominent approaches for global identification/quantification of putative biomarkers for a variety of human diseases, evidence is also provided of the suitability of these sophisticated techniques for the detection of heterogeneous components carried by these fluids.
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Affiliation(s)
- Paolo Iadarola
- Department of Biology and Biotechnologies "L. Spallanzani,", Biochemistry Unit, University of Pavia, Italy
| | - Marco Fumagalli
- Department of Biology and Biotechnologies "L. Spallanzani,", Biochemistry Unit, University of Pavia, Italy
| | - Anna Maria Bardoni
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Italy
| | - Roberta Salvini
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Italy
| | - Simona Viglio
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Italy
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28
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Brown EP, Normandin E, Osei-Owusu NY, Mahan AE, Chan YN, Lai JI, Vaccari M, Rao M, Franchini G, Alter G, Ackerman ME. Microscale purification of antigen-specific antibodies. J Immunol Methods 2015; 425:27-36. [PMID: 26078040 DOI: 10.1016/j.jim.2015.06.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 06/05/2015] [Accepted: 06/08/2015] [Indexed: 10/23/2022]
Abstract
Glycosylation of the Fc domain is an important driver of antibody effector function. While assessment of antibody glycoform compositions observed across total plasma IgG has identified differences associated with a variety of clinical conditions, in many cases it is the glycosylation state of only antibodies against a specific antigen or set of antigens that may be of interest, for example, in defining the potential effector function of antibodies produced during disease or after vaccination. Historically, glycoprofiling such antigen-specific antibodies in clinical samples has been challenging due to their low prevalence, the high sample requirement for most methods of glycan determination, and the lack of high-throughput purification methods. New methods of glycoprofiling with lower sample requirements and higher throughput have motivated the development of microscale and automatable methods for purification of antigen-specific antibodies from polyclonal sources such as clinical serum samples. In this work, we present a robot-compatible 96-well plate-based method for purification of antigen-specific antibodies, suitable for such population level glycosylation screening. We demonstrate the utility of this method across multiple antibody sources, using both purified plasma IgG and plasma, and across multiple different antigen types, with enrichment factors greater than 1000-fold observed. Using an on-column IdeS protease treatment, we further describe staged release of Fc and Fab domains, allowing for glycoprofiling of each domain.
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Affiliation(s)
- Eric P Brown
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States
| | - Erica Normandin
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States
| | - Nana Yaw Osei-Owusu
- Molecular and Cellular Biology Program, Dartmouth College, Hanover, NH 03755, United States
| | - Alison E Mahan
- Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, United States
| | - Ying N Chan
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States
| | - Jennifer I Lai
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States
| | - Monica Vaccari
- Animal Models and Vaccine Section, National Cancer Institute, Bethesda, MD 20814, United States
| | - Mangala Rao
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
| | - Genoveffa Franchini
- Animal Models and Vaccine Section, National Cancer Institute, Bethesda, MD 20814, United States
| | - Galit Alter
- Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, United States
| | - Margaret E Ackerman
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States.
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29
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The perfect storm: HLA antibodies, complement, FcγRs, and endothelium in transplant rejection. Trends Mol Med 2015; 21:319-29. [PMID: 25801125 DOI: 10.1016/j.molmed.2015.02.004] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 01/29/2015] [Accepted: 02/11/2015] [Indexed: 02/07/2023]
Abstract
The pathophysiology of antibody-mediated rejection (AMR) in solid organ transplants is multifaceted and predominantly caused by antibodies directed against polymorphic donor human leukocyte antigens (HLAs). Despite the clearly detrimental impact of HLA antibodies (HLA-Abs) on graft function and survival, the prevention, diagnosis, and treatment of AMR remain a challenge. The histological manifestations of AMR reflect the signatures of HLA-Ab-triggered injury, specifically endothelial changes, recipient leukocytic infiltrate, and complement deposition. We review the interconnected mechanisms of HLA-Ab-mediated injury that might synergize in a 'perfect storm' of inflammation. Characterization of antibody features that are critical for effector functions may help to identify HLA-Abs that are more likely to cause rejection. We also highlight recent advances that may pave the way for new, more effective therapies.
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