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Rebak AS, Hendriks IA, Elsborg JD, Buch-Larsen SC, Nielsen CH, Terslev L, Kirsch R, Damgaard D, Doncheva NT, Lennartsson C, Rykær M, Jensen LJ, Christophorou MA, Nielsen ML. A quantitative and site-specific atlas of the citrullinome reveals widespread existence of citrullination and insights into PADI4 substrates. Nat Struct Mol Biol 2024; 31:977-995. [PMID: 38321148 PMCID: PMC11189309 DOI: 10.1038/s41594-024-01214-9] [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: 12/22/2022] [Accepted: 01/04/2024] [Indexed: 02/08/2024]
Abstract
Despite the importance of citrullination in physiology and disease, global identification of citrullinated proteins, and the precise targeted sites, has remained challenging. Here we employed quantitative-mass-spectrometry-based proteomics to generate a comprehensive atlas of citrullination sites within the HL60 leukemia cell line following differentiation into neutrophil-like cells. We identified 14,056 citrullination sites within 4,008 proteins and quantified their regulation upon inhibition of the citrullinating enzyme PADI4. With this resource, we provide quantitative and site-specific information on thousands of PADI4 substrates, including signature histone marks and transcriptional regulators. Additionally, using peptide microarrays, we demonstrate the potential clinical relevance of certain identified sites, through distinct reactivities of antibodies contained in synovial fluid from anti-CCP-positive and anti-CCP-negative people with rheumatoid arthritis. Collectively, we describe the human citrullinome at a systems-wide level, provide a resource for understanding citrullination at the mechanistic level and link the identified targeted sites to rheumatoid arthritis.
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Affiliation(s)
- Alexandra S Rebak
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ivo A Hendriks
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jonas D Elsborg
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sara C Buch-Larsen
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Claus H Nielsen
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Lene Terslev
- Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Rebecca Kirsch
- Disease Systems Biology Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Dres Damgaard
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Nadezhda T Doncheva
- Disease Systems Biology Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Caroline Lennartsson
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Martin Rykær
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lars J Jensen
- Disease Systems Biology Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Michael L Nielsen
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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2
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Rydén M, Sjögren A, Önnerfjord P, Turkiewicz A, Tjörnstrand J, Englund M, Ali N. Exploring the Early Molecular Pathogenesis of Osteoarthritis Using Differential Network Analysis of Human Synovial Fluid. Mol Cell Proteomics 2024; 23:100785. [PMID: 38750696 PMCID: PMC11252953 DOI: 10.1016/j.mcpro.2024.100785] [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: 08/15/2023] [Revised: 04/17/2024] [Accepted: 05/11/2024] [Indexed: 06/23/2024] Open
Abstract
The molecular mechanisms that drive the onset and development of osteoarthritis (OA) remain largely unknown. In this exploratory study, we used a proteomic platform (SOMAscan assay) to measure the relative abundance of more than 6000 proteins in synovial fluid (SF) from knees of human donors with healthy or mildly degenerated tissues, and knees with late-stage OA from patients undergoing knee replacement surgery. Using a linear mixed effects model, we estimated the differential abundance of 6251 proteins between the three groups. We found 583 proteins upregulated in the late-stage OA, including MMP1, collagenase 3 and interleukin-6. Further, we selected 760 proteins (800 aptamers) based on absolute fold changes between the healthy and mild degeneration groups. To those, we applied Gaussian Graphical Models (GGMs) to analyze the conditional dependence of proteins and to identify key proteins and subnetworks involved in early OA pathogenesis. After regularization and stability selection, we identified 102 proteins involved in GGM networks. Notably, network complexity was lost in the protein graph for mild degeneration when compared to controls, suggesting a disruption in the regular protein interplay. Furthermore, among our main findings were several downregulated (in mild degeneration versus healthy) proteins with unique interactions in the healthy group, one of which, SLCO5A1, has not previously been associated with OA. Our results suggest that this protein is important for healthy joint function. Further, our data suggests that SF proteomics, combined with GGMs, can reveal novel insights into the molecular pathogenesis and identification of biomarker candidates for early-stage OA.
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Affiliation(s)
- Martin Rydén
- Clinical Epidemiology Unit, Department of Clinical Sciences Lund, Orthopedics, Faculty of Medicine, Lund University, Lund, Sweden
| | - Amanda Sjögren
- Clinical Epidemiology Unit, Department of Clinical Sciences Lund, Orthopedics, Faculty of Medicine, Lund University, Lund, Sweden.
| | - Patrik Önnerfjord
- Department of Clinical Sciences Lund, Rheumatology, Rheumatology and Molecular Skeletal Biology, Faculty of Medicine, Lund University, Lund, Sweden
| | - Aleksandra Turkiewicz
- Clinical Epidemiology Unit, Department of Clinical Sciences Lund, Orthopedics, Faculty of Medicine, Lund University, Lund, Sweden
| | - Jon Tjörnstrand
- Department of Orthopaedics, Skåne University Hospital, Lund, Sweden
| | - Martin Englund
- Clinical Epidemiology Unit, Department of Clinical Sciences Lund, Orthopedics, Faculty of Medicine, Lund University, Lund, Sweden
| | - Neserin Ali
- Clinical Epidemiology Unit, Department of Clinical Sciences Lund, Orthopedics, Faculty of Medicine, Lund University, Lund, Sweden
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3
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Thomas MA, Naik P, Wang H, Giles JT, Girgis AA, Kim SY, Johnson TP, Curran AM, Crawford JD, Jahanbani S, Bingham CO, Robinson WH, Na CH, Darrah E. The monocyte cell surface is a unique site of autoantigen generation in rheumatoid arthritis. Proc Natl Acad Sci U S A 2024; 121:e2304199121. [PMID: 38630712 PMCID: PMC11047081 DOI: 10.1073/pnas.2304199121] [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: 03/15/2023] [Accepted: 03/22/2024] [Indexed: 04/19/2024] Open
Abstract
Although anti-citrullinated protein autoantibodies (ACPAs) are a hallmark serological feature of rheumatoid arthritis (RA), the mechanisms and cellular sources behind the generation of the RA citrullinome remain incompletely defined. Peptidylarginine deiminase IV (PAD4), one of the key enzymatic drivers of citrullination in the RA joint, is expressed by granulocytes and monocytes; however, the subcellular localization and contribution of monocyte-derived PAD4 to the generation of citrullinated autoantigens remain underexplored. In this study, we demonstrate that PAD4 displays a widespread cellular distribution in monocytes, including expression on the cell surface. Surface PAD4 was enzymatically active and capable of citrullinating extracellular fibrinogen and endogenous surface proteins in a calcium dose-dependent manner. Fibrinogen citrullinated by monocyte-surface PAD4 could be specifically recognized over native fibrinogen by a panel of eight human monoclonal ACPAs. Several unique PAD4 substrates were identified on the monocyte surface via mass spectrometry, with citrullination of the CD11b and CD18 components of the Mac-1 integrin complex being the most abundant. Citrullinated Mac-1 was found to be a target of ACPAs in 25% of RA patients, and Mac-1 ACPAs were significantly associated with HLA-DRB1 shared epitope alleles, higher C-reactive protein and IL-6 levels, and more erosive joint damage. Our findings implicate the monocyte cell surface as a unique and consequential site of extracellular and cell surface autoantigen generation in RA.
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Affiliation(s)
- Mekha A. Thomas
- Division of Rheumatology, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD21224
| | - Pooja Naik
- Division of Rheumatology, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD21224
| | - Hong Wang
- Division of Rheumatology, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD21224
| | - Jon T. Giles
- Division of Rheumatology, Columbia University, College of Physicians and Surgeons, New York, NY10032
| | - Alexander A. Girgis
- Division of Rheumatology, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD21224
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD21224
| | - Seok-Young Kim
- Department of Neurology, Institute for Cell Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD21205
| | - Tory P. Johnson
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD20892
| | - Ashley M. Curran
- Division of Rheumatology, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD21224
| | - Jonathan D. Crawford
- Division of Rheumatology, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD21224
| | - Shaghayegh Jahanbani
- Division of Immunology and Rheumatology, Stanford University, Stanford, CA94304
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA94550
| | - Clifton O. Bingham
- Division of Rheumatology, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD21224
| | - William H. Robinson
- Division of Immunology and Rheumatology, Stanford University, Stanford, CA94304
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA94550
| | - Chan Hyun Na
- Department of Neurology, Institute for Cell Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD21205
| | - Erika Darrah
- Division of Rheumatology, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD21224
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Martinez GJ, Appleton M, Kipp ZA, Loria AS, Min B, Hinds TD. Glucocorticoids, their uses, sexual dimorphisms, and diseases: new concepts, mechanisms, and discoveries. Physiol Rev 2024; 104:473-532. [PMID: 37732829 PMCID: PMC11281820 DOI: 10.1152/physrev.00021.2023] [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: 05/22/2023] [Revised: 08/07/2023] [Accepted: 09/10/2023] [Indexed: 09/22/2023] Open
Abstract
The normal stress response in humans is governed by the hypothalamic-pituitary-adrenal (HPA) axis through heightened mechanisms during stress, raising blood levels of the glucocorticoid hormone cortisol. Glucocorticoids are quintessential compounds that balance the proper functioning of numerous systems in the mammalian body. They are also generated synthetically and are the preeminent therapy for inflammatory diseases. They act by binding to the nuclear receptor transcription factor glucocorticoid receptor (GR), which has two main isoforms (GRα and GRβ). Our classical understanding of glucocorticoid signaling is from the GRα isoform, which binds the hormone, whereas GRβ has no known ligands. With glucocorticoids being involved in many physiological and cellular processes, even small disruptions in their release via the HPA axis, or changes in GR isoform expression, can have dire ramifications on health. Long-term chronic glucocorticoid therapy can lead to a glucocorticoid-resistant state, and we deliberate how this impacts disease treatment. Chronic glucocorticoid treatment can lead to noticeable side effects such as weight gain, adiposity, diabetes, and others that we discuss in detail. There are sexually dimorphic responses to glucocorticoids, and women tend to have a more hyperresponsive HPA axis than men. This review summarizes our understanding of glucocorticoids and critically analyzes the GR isoforms and their beneficial and deleterious mechanisms and the sexual differences that cause a dichotomy in responses. We also discuss the future of glucocorticoid therapy and propose a new concept of dual GR isoform agonist and postulate why activating both isoforms may prevent glucocorticoid resistance.
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Affiliation(s)
- Genesee J Martinez
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
| | - Malik Appleton
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
| | - Zachary A Kipp
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
| | - Analia S Loria
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
- Barnstable Brown Diabetes Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States
| | - Booki Min
- Department of Microbiology and Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States
| | - Terry D Hinds
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
- Barnstable Brown Diabetes Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, United States
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5
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Rebak AS, Hendriks IA, Nielsen ML. Characterizing citrullination by mass spectrometry-based proteomics. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220237. [PMID: 37778389 PMCID: PMC10542455 DOI: 10.1098/rstb.2022.0237] [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: 03/15/2023] [Accepted: 05/25/2023] [Indexed: 10/03/2023] Open
Abstract
Citrullination is an important post-translational modification (PTM) of arginine, known to play a role in autoimmune disorders, innate immunity response and maintenance of stem cell potency. However, citrullination remains poorly characterized and not as comprehensively understood compared to other PTMs, such as phosphorylation and ubiquitylation. High-resolution mass spectrometry (MS)-based proteomics offers a valuable approach for studying citrullination in an unbiased manner, allowing confident identification of citrullination modification sites and distinction from deamidation events on asparagine and glutamine. MS efforts have already provided valuable insights into peptidyl arginine deaminase targeting along with site-specific information of citrullination in for example synovial fluids derived from rheumatoid arthritis patients. Still, there is unrealized potential for the wider citrullination field by applying MS-based mass spectrometry approaches for proteome-wide investigations. Here we will outline contemporary methods and current challenges for studying citrullination by MS, and discuss how the development of neoteric citrullination-specific proteomics approaches still may improve our understanding of citrullination networks. This article is part of the Theo Murphy meeting issue 'The virtues and vices of protein citrullination'.
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Affiliation(s)
- A. S. Rebak
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - I. A. Hendriks
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - M. L. Nielsen
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
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6
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Saifi MA, Ho IC. Citrullination of matrisomal proteins in health and diseases. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220244. [PMID: 37778384 PMCID: PMC10542447 DOI: 10.1098/rstb.2022.0244] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 04/24/2023] [Indexed: 10/03/2023] Open
Abstract
Proteins once translated are subjected to post-translational modifications (PTMs) that can critically modify their characteristics. Citrullination is a unique type of PTM that is catalysed by peptidylarginine deiminase (PAD) enzymes, which regulate a multitude of physiological functions such as apoptosis, gene expression and immune response by altering the structure and function of cellular proteins. However, emerging data have unravelled compelling evidence to support that PAD-mediated citrullination is not exclusive to cellular proteins; rather citrullination of extracellular matrix (ECM) proteins also plays a major contributing role in various physiological/pathological conditions. Here, we discuss putative mechanisms for citrullination-induced alterations in the function of ECM proteins. Further, we put emphasis on influential roles of ECM citrullination in various pathological scenarios to underscore the clinical potential of its manipulation in human diseases. This article is part of the Theo Murphy meeting issue 'The virtues and vices of protein citrullination'.
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Affiliation(s)
- Mohammad Aslam Saifi
- Division of Rheumatology, Inflammation, and Immunity, Department of Medicine, Brigham and Women's Hospital, 60 Fenwood Road, Boston, MA 02115, USA
- Harvard Medical School, Boston, MA 02115, USA
| | - I-Cheng Ho
- Division of Rheumatology, Inflammation, and Immunity, Department of Medicine, Brigham and Women's Hospital, 60 Fenwood Road, Boston, MA 02115, USA
- Harvard Medical School, Boston, MA 02115, USA
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7
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Neeli I, Moarefian M, Kuseladass J, Dwivedi N, Jones C, Radic M. Neutrophil attachment via Mac-1 ( αMβ2; CD11b/CD18; CR3) integrins induces PAD4 deimination of profilin and histone H3. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220247. [PMID: 37778386 PMCID: PMC10542442 DOI: 10.1098/rstb.2022.0247] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 08/07/2023] [Indexed: 10/03/2023] Open
Abstract
Neutrophil adhesion to endothelia, entry into tissues and chemotaxis constitute essential steps in the immune response to infections that drive inflammation. Neutrophils bind to other cells and migrate via adhesion receptors, notably the αMβ2 integrin dimer (also called Mac-1, CR3 or CD11b/CD18). Here, the response of neutrophils to integrin engagement was examined by monitoring the activity of peptidylarginine deiminase 4 (PAD4). Histone H3 deimination was strongly stimulated by manganese, an integrin-activating divalent cation, even in the absence of additional inflammatory stimuli. Manganese-induced cell attachment resulted in neutrophil swarm formation that paralleled histone deimination, whereas antibodies that impair integrin binding prevented both cell adhesion and histone deimination. Manganese treatment led to putative deimination of profilin, a protein that functions as an actin-organizing hub, as detected by two-dimensional gel electrophoresis and citrulline immunoblotting. Cl-amidine, a covalent inhibitor of PAD4, and GSK484, a specific PAD4 inhibitor, blocked profilin deimination. Neutrophil migration toward leukotriene B4 and toward synovial fluid from a rheumatoid arthritis patient were inhibited by chloramidine, thus supporting the contribution of deimination to chemotaxis. The data, based on a simplified system for integrin activation, imply a mechanism whereby integrin attachment coordinates neutrophil responses to inflammation and orchestrates deimination of nuclear and cytoskeletal proteins. This article is part of the Theo Murphy meeting issue 'The virtues and vices of protein citrullination'.
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Affiliation(s)
- Indira Neeli
- Department of Microbiology, Immunology, and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Maryam Moarefian
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Jayalakshmi Kuseladass
- Department of Microbiology, Immunology, and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Nishant Dwivedi
- Department of Microbiology, Immunology, and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Caroline Jones
- Department of Bioengineering, Erik Jonsson School of Engineering and Computer Science, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Marko Radic
- Department of Microbiology, Immunology, and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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Martin M, Nilsson SC, Eikrem D, Fromell K, Scavenius C, Vogt LM, Bielecka E, Potempa J, Enghild JJ, Nilsson B, Ekdahl KN, Kapetanovic MC, Blom AM. Citrullination of C1-inhibitor as a mechanism of impaired complement regulation in rheumatoid arthritis. Front Immunol 2023; 14:1203506. [PMID: 37426666 PMCID: PMC10326043 DOI: 10.3389/fimmu.2023.1203506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 06/05/2023] [Indexed: 07/11/2023] Open
Abstract
Background Dysregulated complement activation, increased protein citrullination, and production of autoantibodies against citrullinated proteins are hallmarks of rheumatoid arthritis (RA). Citrullination is induced by immune cell-derived peptidyl-Arg deiminases (PADs), which are overactivated in the inflamed synovium. We characterized the effect of PAD2- and PAD4-induced citrullination on the ability of the plasma-derived serpin C1-inhibitor (C1-INH) to inhibit complement and contact system activation. Methods Citrullination of the C1-INH was confirmed by ELISA and Western blotting using a biotinylated phenylglyoxal probe. C1-INH-mediated inhibition of complement activation was analyzed by C1-esterase activity assay. Downstream inhibition of complement was studied by C4b deposition on heat-aggregated IgGs by ELISA, using pooled normal human serum as a complement source. Inhibition of the contact system was investigated by chromogenic activity assays for factor XIIa, plasma kallikrein, and factor XIa. In addition, autoantibody reactivity to native and citrullinated C1-INH was measured by ELISA in 101 RA patient samples. Results C1-INH was efficiently citrullinated by PAD2 and PAD4. Citrullinated C1-INH was not able to bind the serine protease C1s and inhibit its activity. Citrullination of the C1-INH abrogated its ability to dissociate the C1-complex and thus inhibit complement activation. Consequently, citrullinated C1-INH had a decreased capacity to inhibit C4b deposition via the classical and lectin pathways. The inhibitory effect of C1-INH on the contact system components factor XIIa, plasma kallikrein, and factor XIa was also strongly reduced by citrullination. In RA patient samples, autoantibody binding to PAD2- and PAD4-citrullinated C1-INH was detected. Significantly more binding was observed in anti-citrullinated protein antibody (ACPA)-positive than in ACPA-negative samples. Conclusion Citrullination of the C1-INH by recombinant human PAD2 and PAD4 enzymes impaired its ability to inhibit the complement and contact systems in vitro. Citrullination seems to render C1-INH more immunogenic, and citrullinated C1-INH might thus be an additional target of the autoantibody response observed in RA patients.
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Affiliation(s)
- Myriam Martin
- Department of Translational Medicine, Division of Medical Protein Chemistry, Lund University, Malmö, Sweden
| | - Sara C. Nilsson
- Department of Translational Medicine, Division of Medical Protein Chemistry, Lund University, Malmö, Sweden
| | - David Eikrem
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Karin Fromell
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Carsten Scavenius
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Leonie M. Vogt
- Department of Translational Medicine, Division of Medical Protein Chemistry, Lund University, Malmö, Sweden
| | - Ewa Bielecka
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | - Jan Potempa
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, United States
| | - Jan J. Enghild
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Bo Nilsson
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Kristina N. Ekdahl
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
- School of Natural Sciences, Linnæus University, Kalmar, Sweden
| | - Meliha C. Kapetanovic
- Department of Clinical Sciences Lund, Rheumatology, Lund University, Skåne University Hospital, Lund, Sweden
| | - Anna M. Blom
- Department of Translational Medicine, Division of Medical Protein Chemistry, Lund University, Malmö, Sweden
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Reis LR, Souza Junior DR, Tomasin R, Bruni-Cardoso A, Di Mascio P, Ronsein GE. Citrullination of actin-ligand and nuclear structural proteins, cytoskeleton reorganization and protein redistribution across cellular fractions are early events in ionomycin-induced NETosis. Redox Biol 2023; 64:102784. [PMID: 37356135 DOI: 10.1016/j.redox.2023.102784] [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: 05/17/2023] [Revised: 06/07/2023] [Accepted: 06/12/2023] [Indexed: 06/27/2023] Open
Abstract
Neutrophil extracellular traps (NETs) are web-like structures of DNA coated with cytotoxic proteins and histones released by activated neutrophils through a process called NETosis. NETs release occurs through a sequence of highly organized events leading to chromatin expansion and rupture of nuclear and cellular membranes. In calcium ionophore-induced NETosis, the enzyme peptidylargine deiminase 4 (PAD4) mediates chromatin decondensation through histone citrullination, but the biochemical pathways involved in this process are not fully understood. Here we use live-imaging microscopy and proteomic studies of the neutrophil cellular fractions to investigate the early events in ionomycin-triggered NETosis. We found that before ionomycin-stimulated neutrophils release NETs, profound biochemical changes occur in and around their nucleus, such as, cytoskeleton reorganization, nuclear redistribution of actin-remodeling related proteins, and citrullination of actin-ligand and nuclear structural proteins. Ionomycin-stimulated neutrophils rapidly lose their characteristic polymorphic nucleus, and these changes are promptly communicated to the extracellular environment through the secretion of proteins related to immune response. Therefore, our findings revealed key biochemical mediators in the early process that subsequently culminates with nuclear and cell membranes rupture, and extracellular DNA release.
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Affiliation(s)
- Lorenna Rocha Reis
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | - Rebeka Tomasin
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Alexandre Bruni-Cardoso
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Paolo Di Mascio
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Graziella Eliza Ronsein
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil.
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10
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Castellar-Mendoza C, Castillo DM, Chila-Moreno L, Bautista-Molano W, Romero-Sánchez C. Porphyromonas gulae and PPAD antibodies are not related to citrullination in rheumatoid arthritis. Clin Oral Investig 2023:10.1007/s00784-023-04964-w. [PMID: 37133700 DOI: 10.1007/s00784-023-04964-w] [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: 07/21/2022] [Accepted: 03/19/2023] [Indexed: 05/04/2023]
Abstract
INTRODUCTION Porphyromonas gulae have the enzyme PPAD, as P. gingivalis, which is responsible for citrullination related to the pathophysiology of rheumatoid arthritis and periodontitis; this implies the presence of two species of PPAD-producing bacteria in the mouth as well as the presence of citrullinated proteins. There are no previous reports or studies investigating an association between P. gulae PPAD in rheumatoid arthritis (RA). OBJECTIVE To assess the presence of P. gulae and anti-citrullinated peptide antibodies of P. gulae PAD in patients with RA and their possible relationship with clinical activity markers. SUBJECTS AND METHODS A total of 95 patients with RA and 95 controls were included. Erythrocyte sedimentation rate (ESR), C-reactive protein, anti-citrullinated protein antibodies (ACPAs) and rheumatoid factor (RF) were measured. Activity index-28 (DAS28) and SCDAI. The periodontal diagnosis was established. Presence of P. gulae and P. gingivalis. An ELISA was used to determine antibodies against citrullinated peptides of P. gulae PAD. RESULTS A P. gulae frequency of 15.8% was observed in the RA group and 9.5% in the control group. Higher levels of ACPA were found in the P. gulae-positive patients of the RA group, finding no significant difference, but if in patients positive for P. gingivalis with statistical significance (p = 0.0001). The frequency of anti-VDK-cit and anti-LPQ-cit9 antibodies to PPAD of P. gulae was higher in the RA group than in the control group without significant difference. No relationship was found with the clinical variables despite the presence of P. gulae and anti-citrullinated peptide antibodies of P. gulae PPAD in patients with RA CONCLUSIONS: It was not possible to establish a connection with clinical variables in RA and P. gulae; as a result, the presence of P. gingivalis continues to contribute significantly to the increase in antibodies against citrullinated proteins/peptides from exogenous sources of citrullination in RA and periodontitis.
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Affiliation(s)
| | - Diana Marcela Castillo
- Oral Basic Research Unit (UIBO), Research Vice-Rectory, School of Dentistry, Universidad El Bosque, Av. Carrera 9 #131A-02, Bogotá, Colombia
| | - Lorena Chila-Moreno
- School of Dentistry, INMUBO Cellular and Molecular Immunology Group, Universidad El Bosque, Av. Carrera 9 #131A-02, Bogotá, Colombia
- School of Medicine, Clinical Immunology Group, Universidad Militar Nueva Granada/Hospital Militar Central, Transversal 3ª #49-00, Bogotá, Colombia
| | - Wilson Bautista-Molano
- School of Dentistry, INMUBO Cellular and Molecular Immunology Group, Universidad El Bosque, Av. Carrera 9 #131A-02, Bogotá, Colombia
- School of Medicine, Clinical Immunology Group, Universidad Militar Nueva Granada/Hospital Militar Central, Transversal 3ª #49-00, Bogotá, Colombia
| | - Consuelo Romero-Sánchez
- School of Dentistry, INMUBO Cellular and Molecular Immunology Group, Universidad El Bosque, Av. Carrera 9 #131A-02, Bogotá, Colombia.
- Department of Rheumatology and Immunology/Clinical Immunology Group, Hospital Militar Central, Transversal 3ª #49-00, Bogotá, Colombia.
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11
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Christensen AO, Li G, Young CH, Snow B, Khan SA, DeVore SB, Edwards S, Bouma GJ, Navratil AM, Cherrington BD, Rothfuss HM. Peptidylarginine deiminase enzymes and citrullinated proteins in female reproductive physiology and associated diseases†. Biol Reprod 2022; 107:1395-1410. [PMID: 36087287 PMCID: PMC10248218 DOI: 10.1093/biolre/ioac173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/30/2022] [Accepted: 09/07/2022] [Indexed: 09/15/2023] Open
Abstract
Citrullination, the post-translational modification of arginine residues, is catalyzed by the four catalytically active peptidylarginine deiminase (PAD or PADI) isozymes and alters charge to affect target protein structure and function. PADs were initially characterized in rodent uteri and, since then, have been described in other female tissues including ovaries, breast, and the lactotrope and gonadotrope cells of the anterior pituitary gland. In these tissues and cells, estrogen robustly stimulates PAD expression resulting in changes in levels over the course of the female reproductive cycle. The best-characterized targets for PADs are arginine residues in histone tails, which, when citrullinated, alter chromatin structure and gene expression. Methodological advances have allowed for the identification of tissue-specific citrullinomes, which reveal that PADs citrullinate a wide range of enzymes and structural proteins to alter cell function. In contrast to their important physiological roles, PADs and citrullinated proteins are also involved in several female-specific diseases including autoimmune disorders and reproductive cancers. Herein, we review current knowledge regarding PAD expression and function and highlight the role of protein citrullination in both normal female reproductive tissues and associated diseases.
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Affiliation(s)
- Amanda O Christensen
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | - Guangyuan Li
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | - Coleman H Young
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | - Bryce Snow
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | | | - Stanley B DeVore
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Sydney Edwards
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Gerrit J Bouma
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Amy M Navratil
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | - Brian D Cherrington
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | - Heather M Rothfuss
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
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12
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Yang ML, Kibbey RG, Mamula MJ. Biomarkers of autoimmunity and beta cell metabolism in type 1 diabetes. Front Immunol 2022; 13:1028130. [PMID: 36389721 PMCID: PMC9647083 DOI: 10.3389/fimmu.2022.1028130] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 10/13/2022] [Indexed: 09/10/2023] Open
Abstract
Posttranslational protein modifications (PTMs) are an inherent response to physiological changes causing altered protein structure and potentially modulating important biological functions of the modified protein. Besides cellular metabolic pathways that may be dictated by PTMs, the subtle change of proteins also may provoke immune attack in numerous autoimmune diseases. Type 1 diabetes (T1D) is a chronic autoimmune disease destroying insulin-producing beta cells within the pancreatic islets, a result of tissue inflammation to specific autoantigens. This review summarizes how PTMs arise and the potential pathological consequence of PTMs, with particular focus on specific autoimmunity to pancreatic beta cells and cellular metabolic dysfunction in T1D. Moreover, we review PTM-associated biomarkers in the prediction, diagnosis and in monitoring disease activity in T1D. Finally, we will discuss potential preventive and therapeutic approaches of targeting PTMs in repairing or restoring normal metabolic pathways in pancreatic islets.
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Affiliation(s)
- Mei-Ling Yang
- Section of Rheumatology, Allergy and Immunology, Department of Internal Medicine, Yale University, New Haven, CT, United States
| | - Richard G. Kibbey
- Section of Endocrinology, Department of Internal Medicine, Yale University, New Haven, CT, United States
| | - Mark J. Mamula
- Section of Rheumatology, Allergy and Immunology, Department of Internal Medicine, Yale University, New Haven, CT, United States
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13
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Darie-Ion L, Whitham D, Jayathirtha M, Rai Y, Neagu AN, Darie CC, Petre BA. Applications of MALDI-MS/MS-Based Proteomics in Biomedical Research. Molecules 2022; 27:6196. [PMID: 36234736 PMCID: PMC9570737 DOI: 10.3390/molecules27196196] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 11/22/2022] Open
Abstract
Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) is one of the most widely used techniques in proteomics to achieve structural identification and characterization of proteins and peptides, including their variety of proteoforms due to post-translational modifications (PTMs) or protein-protein interactions (PPIs). MALDI-MS and MALDI tandem mass spectrometry (MS/MS) have been developed as analytical techniques to study small and large molecules, offering picomole to femtomole sensitivity and enabling the direct analysis of biological samples, such as biofluids, solid tissues, tissue/cell homogenates, and cell culture lysates, with a minimized procedure of sample preparation. In the last decades, structural identification of peptides and proteins achieved by MALDI-MS/MS helped researchers and clinicians to decipher molecular function, biological process, cellular component, and related pathways of the gene products as well as their involvement in pathogenesis of diseases. In this review, we highlight the applications of MALDI ionization source and tandem approaches for MS for analyzing biomedical relevant peptides and proteins. Furthermore, one of the most relevant applications of MALDI-MS/MS is to provide "molecular pictures", which offer in situ information about molecular weight proteins without labeling of potential targets. Histology-directed MALDI-mass spectrometry imaging (MSI) uses MALDI-ToF/ToF or other MALDI tandem mass spectrometers for accurate sequence analysis of peptide biomarkers and biological active compounds directly in tissues, to assure complementary and essential spatial data compared with those obtained by LC-ESI-MS/MS technique.
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Affiliation(s)
- Laura Darie-Ion
- Laboratory of Biochemistry, Department of Chemistry, “Alexandru Ioan Cuza” University of Iasi, Carol I bvd, No. 11, 700506 Iasi, Romania
| | - Danielle Whitham
- Biochemistry & Proteomics Laboratories, Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699, USA
| | - Madhuri Jayathirtha
- Biochemistry & Proteomics Laboratories, Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699, USA
| | - Yashveen Rai
- Biochemistry & Proteomics Laboratories, Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699, USA
| | - Anca-Narcisa Neagu
- Laboratory of Animal Histology, Faculty of Biology, “Alexandru Ioan Cuza” University of Iasi, Carol I bvd, No. 22, 700505 Iasi, Romania
| | - Costel C. Darie
- Biochemistry & Proteomics Laboratories, Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699, USA
| | - Brînduşa Alina Petre
- Laboratory of Biochemistry, Department of Chemistry, “Alexandru Ioan Cuza” University of Iasi, Carol I bvd, No. 11, 700506 Iasi, Romania
- Biochemistry & Proteomics Laboratories, Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699, USA
- Center for Fundamental Research and Experimental Development in Translation Medicine–TRANSCEND, Regional Institute of Oncology, 700483 Iasi, Romania
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14
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Gómez-Bañuelos E, Konig MF, Andrade F. Microbial pathways to subvert host immunity generate citrullinated neoantigens targeted in rheumatoid arthritis. Curr Opin Struct Biol 2022; 75:102423. [PMID: 35834948 PMCID: PMC9668488 DOI: 10.1016/j.sbi.2022.102423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 06/08/2022] [Accepted: 06/13/2022] [Indexed: 11/03/2022]
Abstract
The specific association between antibodies to citrullinated proteins and rheumatoid arthritis (RA) has centered interest on understanding why citrullinated proteins become immunogenic in this disease, which is believed to inform the origins of autoimmunity in RA. Since citrullination is a physiologic post-translational modification (PTM), one theory is that conditions promoting abnormal citrullination are initiators of self-reactive immune responses to citrullinated proteins in RA. Foremost candidates that dysregulate the normal balance of citrullination are microbial agents, which can exploit citrullination as an effector mechanism to subvert host antimicrobial activities and maximize their progeny. Here, we will use the host-pathogen interface as a unifying model to link microbe-induced citrullination and the loss of immunological tolerance to citrullinated antigens in RA.
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Affiliation(s)
- Eduardo Gómez-Bañuelos
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA. https://twitter.com/@Eduardo95668787
| | - Maximilian F Konig
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA. https://twitter.com/@MaxKonigMD
| | - Felipe Andrade
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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15
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Chen Y, Weng L, Liu W, Deng C, Xuan J, Ma Y, Li C, Jiang J, Chen J, Ge S. Characterization of Monoclonal Antibodies Recognizing Citrulline-Modified Residues. Front Immunol 2022; 13:849779. [PMID: 35359951 PMCID: PMC8961739 DOI: 10.3389/fimmu.2022.849779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
BackgroundCitrullination is a post-translational protein modification linked to the occurrence and development of a variety of diseases. The detection of citrullinated proteins is predominately based on antibody detection although currently available reagents demonstrate detection bias according to the environmental context of the citrullinated residues. This study aimed to develop improved antibody reagents capable of detecting citrullinated residues in proteins in an unbiased manner.MethodsBALB/c mice were sequentially immunized using citrulline conjugates with different carrier proteins, and specific monoclonal antibodies (mAbs) identified by primary screening using citrulline-conjugated proteins unrelated to the immunogen. Secondary screening was performed to identify mAbs whose reactivity could be specifically blocked by free citrulline, followed by identification and performance assessment.ResultsTwo mAbs, 22F1 and 30G2, specifically recognizing a single citrulline residue were screened from 22 mAbs reacting with citrulline conjugates. Compared with commercially available anti-citrulline antibodies (AB6464, AB100932 and MABN328), 22F1 and 30G2 demonstrated significantly higher reactivity as well as a broader detection spectrum against different citrullinated proteins. 22F1 and 30G2 also had higher specificity than commercial antibodies and overall better applicability to a range of different immunoassays.ConclusionTwo mAbs specifically recognizing a single citrulline residue were successfully produced, each possessing good specificity against different citrullinated proteins. The improved utility of these reagents is expected to make a strong contribution to protein citrullination-related research.
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Affiliation(s)
- Yaqiong Chen
- Department of Rheumatology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Lin Weng
- Department of Rheumatology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Wei Liu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen, China
| | - Chenxi Deng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen, China
| | - Jinxiu Xuan
- Department of Rheumatology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Yuan Ma
- Department of Rheumatology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Cao Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen, China
| | - Jinlu Jiang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen, China
| | - Juan Chen
- Department of Rheumatology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
- *Correspondence: Juan Chen, ; Shengxiang Ge,
| | - Shengxiang Ge
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen, China
- *Correspondence: Juan Chen, ; Shengxiang Ge,
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16
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Trejo-Zambrano MI, Gómez-Bañuelos E, Andrade F. Redox-Mediated Carbamylation As a Hapten Model Applied to the Origin of Antibodies to Modified Proteins in Rheumatoid Arthritis. Antioxid Redox Signal 2022; 36:389-409. [PMID: 33906423 PMCID: PMC8982126 DOI: 10.1089/ars.2021.0064] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 04/16/2021] [Indexed: 12/23/2022]
Abstract
Significance: The production of antibodies to posttranslationally modified antigens is a hallmark in rheumatoid arthritis (RA). In particular, the presence of citrullination-associated antibodies, targeting both citrullinating enzymes (the peptidylarginine deiminases [PADs]) and citrullinated antigens (anticitrullinated protein antibodies [ACPAs]), has suggested that dysregulated citrullination is relevant for disease pathogenesis. Antibodies to other protein modifications with physicochemical similarities to citrulline, such as carbamylated-lysine and acetylated-lysine, have also gained interest in RA, but their mechanistic relation to ACPAs remains unclear. Recent Advances: Recent studies using RA-derived monoclonal antibodies have found that ACPAs are cross-reactive to carbamylated and acetylated peptides, challenging our understanding of the implications of such cross-reactivity. Critical Issues: Analogous to the classic antibody response to chemically modified proteins, we examine the possibility that antibodies to modified proteins in RA are more likely to resemble antihapten antibodies rather than autoantibodies. This potential shift in the autoantibody paradigm in RA offers the opportunity to explore new mechanisms involved in the origin and cross-reactivity of pathogenic antibodies in RA. In contrast to citrullination, carbamylation is a chemical modification associated with oxidative stress, it is highly immunogenic, and is considered in the group of posttranslational modification-derived products. We discuss the possibility that carbamylated proteins are antigenic drivers of cross-reacting antihapten antibodies that further create the ACPA response, and that ACPAs may direct the production of antibodies to PAD enzymes. Future Directions: Understanding the complexity of autoantibodies in RA is critical to develop tools to clearly define their origin, identify drivers of disease propagation, and develop novel therapeutics. Antioxid. Redox Signal. 36, 389-409.
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Affiliation(s)
| | - Eduardo Gómez-Bañuelos
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Felipe Andrade
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Volkov M, Kampstra ASB, van Schie KA, Kawakami A, Tamai M, Kawashiri S, Maeda T, Huizinga TWJ, Toes REM, van der Woude D. Evolution of anti-modified protein antibody responses can be driven by consecutive exposure to different post-translational modifications. Arthritis Res Ther 2021; 23:298. [PMID: 34876234 PMCID: PMC8653599 DOI: 10.1186/s13075-021-02687-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 11/28/2021] [Indexed: 11/22/2022] Open
Abstract
Background Besides anti-citrullinated protein antibodies (ACPA), rheumatoid arthritis patients (RA) often display autoantibody reactivities against other post-translationally modified (PTM) proteins, more specifically carbamylated and acetylated proteins. Immunizing mice with one particular PTM results in an anti-modified protein antibody (AMPA) response recognizing different PTM-antigens. Furthermore, human AMPA, isolated based on their reactivity to one PTM, cross-react with other PTMs. However, it is unclear whether the AMPA-reactivity profile is “fixed” in time or whether consecutive exposure to different PTMs can shape the evolving AMPA response towards a particular PTM. Methods Longitudinally collected serum samples of 8 human individuals at risk of RA and 5 with early RA were tested with ELISA, and titers were analyzed to investigate the evolution of the AMPA responses over time. Mice (13 per immunization group in total) were immunized with acetylated (or carbamylated) protein (ovalbumin) twice or cross-immunized with an acetylated and then a carbamylated protein (or vice versa) and their serum was analyzed for AMPA responses. Results Human data illustrated dynamic changes in AMPA-reactivity profiles in both individuals at risk of RA and in early RA patients. Mice immunized with either solely acetylated or carbamylated ovalbumin (AcOVA or CaOVA) developed reactivity against both acetylated and carbamylated antigens. Irrespective of the PTM-antigen used for the first immunization, a booster immunization with an antigen bearing the other PTM resulted in increased titers to the second/booster PTM. Furthermore, cross-immunization skewed the overall AMPA-response profile towards a relatively higher reactivity against the “booster” PTM. Conclusions The relationship between different reactivities within the AMPA response is dynamic. The initial exposure to a PTM-antigen induces cross-reactive responses that can be boosted by an antigen bearing this or other PTMs, indicating the formation of cross-reactive immunological memory. Upon subsequent exposure to an antigen bearing another type of PTM, the overall reactivity pattern can be skewed towards better recognition of the later encountered PTM. These data might explain temporal differences in the AMPA-response profile and point to the possibility that the PTM responsible for the initiation of the AMPA response may differ from the PTM predominantly recognized later in time. Supplementary Information The online version contains supplementary material available at 10.1186/s13075-021-02687-5.
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Affiliation(s)
- M Volkov
- Department of Rheumatology, Leiden University Medical Center, PO Box 9600, Albinusdreef 2, 2300 RC, Leiden, The Netherlands.
| | - A S B Kampstra
- Department of Rheumatology, Leiden University Medical Center, PO Box 9600, Albinusdreef 2, 2300 RC, Leiden, The Netherlands
| | - K A van Schie
- Department of Rheumatology, Leiden University Medical Center, PO Box 9600, Albinusdreef 2, 2300 RC, Leiden, The Netherlands
| | - A Kawakami
- Department of Immunology and Rheumatology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - M Tamai
- Department of Immunology and Rheumatology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - S Kawashiri
- Department of Community Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - T Maeda
- Department of General Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - T W J Huizinga
- Department of Rheumatology, Leiden University Medical Center, PO Box 9600, Albinusdreef 2, 2300 RC, Leiden, The Netherlands
| | - R E M Toes
- Department of Rheumatology, Leiden University Medical Center, PO Box 9600, Albinusdreef 2, 2300 RC, Leiden, The Netherlands
| | - D van der Woude
- Department of Rheumatology, Leiden University Medical Center, PO Box 9600, Albinusdreef 2, 2300 RC, Leiden, The Netherlands
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18
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Israr MZ, Bernieh D, Salzano A, Cassambai S, Yazaki Y, Suzuki T. Matrix-assisted laser desorption ionisation (MALDI) mass spectrometry (MS): basics and clinical applications. Clin Chem Lab Med 2021; 58:883-896. [PMID: 32229653 DOI: 10.1515/cclm-2019-0868] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 02/21/2020] [Indexed: 01/23/2023]
Abstract
Background Matrix-assisted laser desorption ionisation (MALDI) mass spectrometry (MS) has been used for more than 30 years. Compared with other analytical techniques, it offers ease of use, high throughput, robustness, cost-effectiveness, rapid analysis and sensitivity. As advantages, current clinical techniques (e.g. immunoassays) are unable to directly measure the biomarker; rather, they measure secondary signals. MALDI-MS has been extensively researched for clinical applications, and it is set for a breakthrough as a routine tool for clinical diagnostics. Content This review reports on the principles of MALDI-MS and discusses current clinical applications and the future clinical prospects for MALDI-MS. Furthermore, the review assesses the limitations currently experienced in clinical assays, the advantages and the impact of MALDI-MS to transform clinical laboratories. Summary MALDI-MS is widely used in clinical microbiology for the screening of microbial isolates; however, there is scope to apply MALDI-MS in the diagnosis, prognosis, therapeutic drug monitoring and biopsy imaging in many diseases. Outlook There is considerable potential for MALDI-MS in clinic as a tool for screening, profiling and imaging because of its high sensitivity and specificity over alternative techniques.
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Affiliation(s)
- Muhammad Zubair Israr
- Department of Cardiovascular Sciences and NIHR Leicester Biomedical Research Centre, University of Leicester, Leicester, UK
| | - Dennis Bernieh
- Department of Cardiovascular Sciences and NIHR Leicester Biomedical Research Centre, University of Leicester, Leicester, UK
| | - Andrea Salzano
- IRCCS SDN, Diagnostic and Nuclear Research Institute, Naples, Italy
| | - Shabana Cassambai
- Department of Cardiovascular Sciences and NIHR Leicester Biomedical Research Centre, University of Leicester, Leicester, UK
| | - Yoshiyuki Yazaki
- Department of Cardiovascular Sciences and NIHR Leicester Biomedical Research Centre, University of Leicester, Leicester, UK
| | - Toru Suzuki
- Department of Cardiovascular Sciences and NIHR Leicester Biomedical Research Centre, University of Leicester, Leicester, UK
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Huang J, Fu X, Chen X, Li Z, Huang Y, Liang C. Promising Therapeutic Targets for Treatment of Rheumatoid Arthritis. Front Immunol 2021; 12:686155. [PMID: 34305919 PMCID: PMC8299711 DOI: 10.3389/fimmu.2021.686155] [Citation(s) in RCA: 87] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 06/23/2021] [Indexed: 12/12/2022] Open
Abstract
Rheumatoid arthritis (RA) is a systemic poly-articular chronic autoimmune joint disease that mainly damages the hands and feet, which affects 0.5% to 1.0% of the population worldwide. With the sustained development of disease-modifying antirheumatic drugs (DMARDs), significant success has been achieved for preventing and relieving disease activity in RA patients. Unfortunately, some patients still show limited response to DMARDs, which puts forward new requirements for special targets and novel therapies. Understanding the pathogenetic roles of the various molecules in RA could facilitate discovery of potential therapeutic targets and approaches. In this review, both existing and emerging targets, including the proteins, small molecular metabolites, and epigenetic regulators related to RA, are discussed, with a focus on the mechanisms that result in inflammation and the development of new drugs for blocking the various modulators in RA.
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Affiliation(s)
- Jie Huang
- Department of Biology, Southern University of Science and Technology, Shenzhen, China
| | - Xuekun Fu
- Department of Biology, Southern University of Science and Technology, Shenzhen, China
| | - Xinxin Chen
- Department of Biology, Southern University of Science and Technology, Shenzhen, China
| | - Zheng Li
- Department of Biology, Southern University of Science and Technology, Shenzhen, China
| | - Yuhong Huang
- Department of Biology, Southern University of Science and Technology, Shenzhen, China
| | - Chao Liang
- Department of Biology, Southern University of Science and Technology, Shenzhen, China.,Institute of Integrated Bioinfomedicine and Translational Science (IBTS), School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China
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Alghamdi MF, Redwan EM. Advances in the diagnosis of autoimmune diseases based on citrullinated peptides/proteins. Expert Rev Mol Diagn 2021; 21:685-702. [PMID: 34024239 DOI: 10.1080/14737159.2021.1933946] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Introduction: Autoimmune diseases are still one of the hard obstacles associated with humanity. There are many exogenous and endogenous etiological factors behind autoimmune diseases, which may be combined or dispersed to stimulate the autoimmune responses. Protein citrullination represents one of these factors. Harnessing specific citrullinated proteins/peptides could early predict and/or diagnose some of the autoimmune diseases. Many generations of diagnostic tools based on citrullinated peptides with comparable specificity/sensitivity are available worldwide.Areas covered: In this review, we discuss the deimination reaction behind the citrullination of most known autoantigens targeted, different generations of diagnostic tools based on citrullinated probes with specificity/sensitivity of each as well as newly developed assays. Furthermore, the most advanced molecular analytical tools to detect the citrullinated residues in the biological fluid and their performance are also evaluated, providing new avenues to early detect autoimmune diseases with high accuracy.Expert opinion: With the current specificity/sensitivity tools available for autoimmune disease detection, emphasis must be placed on developing more advance and effective, early, rapid, and simple diagnostic devices for autoimmune disease monitoring (similar to a portable device for sugar test at home). The molecular analytical devices with dual and/or multiplexe functions should be more simplified and invested in clinical laboratories.
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Affiliation(s)
- Mohammed F Alghamdi
- Biological Sciences Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia.,Laboratory Department, University Medical Services Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Elrashdy M Redwan
- Biological Sciences Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia.,Therapeutic and Protective Proteins Laboratory, Protein Research Department, Genetic Engineering and Biotechnology Research Institute, City for Scientific Research and Technology Applications, New Borg EL-Arab, Alexandria, Egypt
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21
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Yang ML, Sodré FMC, Mamula MJ, Overbergh L. Citrullination and PAD Enzyme Biology in Type 1 Diabetes - Regulators of Inflammation, Autoimmunity, and Pathology. Front Immunol 2021; 12:678953. [PMID: 34140951 PMCID: PMC8204103 DOI: 10.3389/fimmu.2021.678953] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/11/2021] [Indexed: 02/06/2023] Open
Abstract
The generation of post-translational modifications (PTMs) in human proteins is a physiological process leading to structural and immunologic variety in proteins, with potentially altered biological functions. PTMs often arise through normal responses to cellular stress, including general oxidative changes in the tissue microenvironment and intracellular stress to the endoplasmic reticulum or immune-mediated inflammatory stresses. Many studies have now illustrated the presence of 'neoepitopes' consisting of PTM self-proteins that induce robust autoimmune responses. These pathways of inflammatory neoepitope generation are commonly observed in many autoimmune diseases including systemic lupus erythematosus, rheumatoid arthritis, multiple sclerosis, and type 1 diabetes (T1D), among others. This review will focus on one specific PTM to self-proteins known as citrullination. Citrullination is mediated by calcium-dependent peptidylarginine deiminase (PAD) enzymes, which catalyze deimination, the conversion of arginine into the non-classical amino acid citrulline. PADs and citrullinated peptides have been associated with different autoimmune diseases, notably with a prominent role in the diagnosis and pathology of rheumatoid arthritis. More recently, an important role for PADs and citrullinated self-proteins has emerged in T1D. In this review we will provide a comprehensive overview on the pathogenic role for PADs and citrullination in inflammation and autoimmunity, with specific focus on evidence for their role in T1D. The general role of PADs in epigenetic and transcriptional processes, as well as their crucial role in histone citrullination, neutrophil biology and neutrophil extracellular trap (NET) formation will be discussed. The latter is important in view of increasing evidence for a role of neutrophils and NETosis in the pathogenesis of T1D. Further, we will discuss the underlying processes leading to citrullination, the genetic susceptibility factors for increased recognition of citrullinated epitopes by T1D HLA-susceptibility types and provide an overview of reported autoreactive responses against citrullinated epitopes, both of T cells and autoantibodies in T1D patients. Finally, we will discuss recent observations obtained in NOD mice, pointing to prevention of diabetes development through PAD inhibition, and the potential role of PAD inhibitors as novel therapeutic strategy in autoimmunity and in T1D in particular.
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Affiliation(s)
- Mei-Ling Yang
- Section of Rheumatology, Allergy and Clinical Immunology, Department of Internal Medicine, Yale University, New Haven, CT, United States
| | - Fernanda M C Sodré
- Department of Chronic Diseases, Metabolism and Ageing, Laboratory of Clinical and Experimental Endocrinology (CEE), KU Leuven, Leuven, Belgium
| | - Mark J Mamula
- Section of Rheumatology, Allergy and Clinical Immunology, Department of Internal Medicine, Yale University, New Haven, CT, United States
| | - Lut Overbergh
- Department of Chronic Diseases, Metabolism and Ageing, Laboratory of Clinical and Experimental Endocrinology (CEE), KU Leuven, Leuven, Belgium
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22
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Molecular Dynamic Simulations Suggest That Metabolite-Induced Post-Translational Modifications Alter the Behavior of the Fibrinogen Coiled-Coil Domain. Metabolites 2021; 11:metabo11050307. [PMID: 34065002 PMCID: PMC8150326 DOI: 10.3390/metabo11050307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/07/2021] [Accepted: 05/08/2021] [Indexed: 12/02/2022] Open
Abstract
Fibrinogen is an abundant blood plasma protein that, inter alia, participates in blood coagulation. It polymerizes to form a fibrin clot that is among the major components of the thrombus. Fibrinogen reactions with various reactive metabolites may induce post-translational modifications (PTMs) into the protein structure that affect the architecture and properties of fibrin clots. We reviewed the previous literature to find the positions of PTMs of fibrinogen. For 7 out of 307 reported PTMs, we used molecular dynamics simulations to characterize their effect on the behavior of the fibrinogen coiled-coil domain. Interactions of the γ-coil with adjacent chains give rise to π-helices in Aα and Bβ chains of even unmodified fibrinogen. The examined PTMs suppress fluctuations of the γ-coil, which may affect the fibrinolysis and stiffness of the fibrin fibers. Citrullination of AαR104 and oxidations of γP70 and γP76 to glutamic semialdehyde unfold the α-helical structure of Aα and Bβ chains. Oxidation of γM78 to methionine sulfoxide induces the formation of an α-helix in the γ-coil region. Our findings suggest that certain PTMs alter the protein secondary structure. Thus, the altered protein structure may indicate the presence of PTMs in the molecule and consequently of certain metabolites within the system.
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23
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Bay-Jensen AC, Siebuhr AS, Damgaard D, Drobinski P, Thudium C, Mortensen J, Nielsen CH. Objective and noninvasive biochemical markers in rheumatoid arthritis: where are we and where are we going? Expert Rev Proteomics 2021; 18:159-175. [PMID: 33783300 DOI: 10.1080/14789450.2021.1908892] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Rheumatoid arthritis (RA) is a chronic autoimmune disease that affects approximately 1% of the adult population. RA is multi-factorial, and as such our understanding of the molecular pathways involved in the disease is currently limited. An increasing number of studies have suggested that several molecular phenotypes (i.e. endotypes) of RA exist, and that different endotypes respond differently to various treatments. Biochemical markers may be an attractive means for achieving precision medicine, as they are objective and easily obtainable. AREAS COVERED We searched recent publications on biochemical markers in RA as either diagnostic or prognostic markers, or as markers of disease activity. Here, we provide a narrative overview of different classes of markers, such as autoantibodies, citrulline products, markers of tissue turnover and cytokines, that have been tested in clinical cohorts or trials including RA patients. EXPERT OPINION Although many biochemical markers have been identified and tested, few are currently being used in clinical practice. As more treatment options are becoming available, the need for precision medicine tools that can aid physicians and patients in choosing the right treatment is growing.
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Affiliation(s)
- Anne C Bay-Jensen
- ImmunoScience, Nordic Bioscience Biomarkers and Research, Herlev, Denmark
| | - Anne Sofie Siebuhr
- ImmunoScience, Nordic Bioscience Biomarkers and Research, Herlev, Denmark
| | - Dres Damgaard
- Center for Rheumatolology and Spine Diseases, Institute for Inflammation Research, University of Copenhagen, Copenhagen Ø, Denmark
| | - Patryk Drobinski
- ImmunoScience, Nordic Bioscience Biomarkers and Research, Herlev, Denmark
| | - Christian Thudium
- ImmunoScience, Nordic Bioscience Biomarkers and Research, Herlev, Denmark
| | - Joachim Mortensen
- ImmunoScience, Nordic Bioscience Biomarkers and Research, Herlev, Denmark
| | - Claus H Nielsen
- Center for Rheumatolology and Spine Diseases, Institute for Inflammation Research, University of Copenhagen, Copenhagen Ø, Denmark
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24
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Lim JJ, Jones CM, Loh TJ, Ting YT, Zareie P, Loh KL, Felix NJ, Suri A, McKinnon M, Stevenaert F, Sharma RK, Klareskog L, Malmström V, Baker DG, Purcell AW, Reid HH, La Gruta NL, Rossjohn J. The shared susceptibility epitope of HLA-DR4 binds citrullinated self-antigens and the TCR. Sci Immunol 2021; 6:6/58/eabe0896. [PMID: 33863750 DOI: 10.1126/sciimmunol.abe0896] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 03/18/2021] [Indexed: 12/11/2022]
Abstract
Individuals expressing HLA-DR4 bearing the shared susceptibility epitope (SE) have an increased risk of developing rheumatoid arthritis (RA). Posttranslational modification of self-proteins via citrullination leads to the formation of neoantigens that can be presented by HLA-DR4 SE allomorphs. However, in T cell-mediated autoimmunity, the interplay between the HLA molecule, posttranslationally modified epitope(s), and the responding T cell repertoire remains unclear. In HLA-DR4 transgenic mice, we show that immunization with a Fibβ-74cit69-81 peptide led to a population of HLA-DR4Fibβ-74cit69-81 tetramer+ T cells that exhibited biased T cell receptor (TCR) β chain usage, which was attributable to selective clonal expansion from the preimmune repertoire. Crystal structures of pre- and postimmune TCRs showed that the SE of HLA-DR4 represented a main TCR contact zone. Immunization with a double citrullinated epitope (Fibβ-72,74cit69-81) altered the responding HLA-DR4 tetramer+ T cell repertoire, which was due to the P2-citrulline residue interacting with the TCR itself. We show that the SE of HLA-DR4 has dual functionality, namely, presentation and a direct TCR recognition determinant. Analogous biased TCR β chain usage toward the Fibβ-74cit69-81 peptide was observed in healthy HLA-DR4+ individuals and patients with HLA-DR4+ RA, thereby suggesting a link to human RA.
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Affiliation(s)
- Jia Jia Lim
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Claerwen M Jones
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Tiing Jen Loh
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Yi Tian Ting
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Pirooz Zareie
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Khai L Loh
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Nathan J Felix
- Janssen Research & Development LLC, Horsham, Philadelphia, PA, USA
| | - Anish Suri
- Janssen Research & Development, Turnhoutseweg 30, BE-2340, Beerse, Belgium
| | - Murray McKinnon
- Janssen Research & Development LLC, Horsham, Philadelphia, PA, USA
| | | | - Ravi K Sharma
- Rheumatology Division, Department of Medicine, Karolinska Institutet, Karolinska University Hospital, 17177 Stockholm, Sweden
| | - Lars Klareskog
- Rheumatology Division, Department of Medicine, Karolinska Institutet, Karolinska University Hospital, 17177 Stockholm, Sweden
| | - Vivianne Malmström
- Rheumatology Division, Department of Medicine, Karolinska Institutet, Karolinska University Hospital, 17177 Stockholm, Sweden
| | - Daniel G Baker
- Janssen Research & Development LLC, Horsham, Philadelphia, PA, USA
| | - Anthony W Purcell
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Hugh H Reid
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia. .,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Nicole L La Gruta
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.
| | - Jamie Rossjohn
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia. .,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.,Institute of Infection and Immunity, Cardiff University, School of Medicine, Heath Park, Cardiff CF14 4XN, UK
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25
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Epitope-Based Chicken-Derived Novel Anti-PAD2 Monoclonal Antibodies Inhibit Citrullination. J Immunol Res 2021; 2021:6659960. [PMID: 33937418 PMCID: PMC8055403 DOI: 10.1155/2021/6659960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/10/2021] [Accepted: 03/25/2021] [Indexed: 01/10/2023] Open
Abstract
The aberrant upregulation of protein arginine deiminase 2- (PAD2-) catalyzed citrullination is reported in various autoimmune diseases (rheumatoid arthritis and multiple sclerosis) and several cancers. Currently, there are no anti-PAD2 monoclonal antibodies (mAbs) that can inhibit the citrullination reaction. Here, an epitope 341YLNRGDRWIQDEIEFGY357 was examined as an antigenic site of PAD2. Chickens were immunized with this epitope, and the generated mAbs were screened for its reactivity against the full-length PAD2. Enzyme-linked immunosorbent assay revealed that six mAbs, which were screened from the phage display library, crossreacted with mouse PAD2. Kinetic analysis revealed that mAbs are bound to PAD2 in the nanomolar range, which indicated a strong binding. Results of the in vitro citrullination inhibition assay revealed that the half-maximal effective concentration values of mAbs for the inhibition of histone or benzoyl-L-arginine ethyl ester citrullination were in the range of 6–75 nM which supports strong inhibition capabilities. Alanine scanning of epitope revealed that the peptide fragment 344RGDRWIQDEIEF355 was responsible for generating strong antibody responses that inhibit the PAD2-catalyzed citrullination reaction. These antibodies can aid in understanding the extracellular PAD2 function and treating diseases associated with aberrant citrullination.
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26
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Villacrés C, Spicer V, Krokhin OV. Confident Identification of Citrullination and Carbamylation Assisted by Peptide Retention Time Prediction. J Proteome Res 2021; 20:1571-1581. [PMID: 33523662 DOI: 10.1021/acs.jproteome.0c00775] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The chromatographic behavior of peptides carrying citrulline and homocitrulline residues in proteomic two-dimensional (2D) liquid chromatography-mass spectrometry (LC-MS) experiments has been investigated. The primary goal of this study was to determine the chromatographic conditions that allow differentiating between arginine citrullination and deamidation of asparagine based on retention data, improving the confidence of MS-based identifications. Carbamylation was used as a reference point due to a high degree of similarity between modification products and anticipated changes in chromatographic behavior. We applied 2D LC-MS/MS (a high-pH-low-pH reversed phase (RP), hydrophilic interaction liquid chromatography (HILIC)-low-pH RP, and strong cation exchange (SCX)-low-pH RP) to acquire retention data for modified-nonmodified peptide pairs in the four separation modes. Modifications of a standard protein mixture were induced enzymatically (PAD-2) or chemically (urea) for citrullination and carbamylation, respectively. Deamidation occurs spontaneously. Similar retention shifts were observed for all three modifications in a high-pH RP (decrease) and a low-pH RP (increase), thus limiting the applicability of this 2D LC combination. HILIC on bare silica and strong cation exchange separations have been probed to amplify the effect of charge loss upon citrullination, with SCX demonstrating the most differentiating power: the elimination of basic residues upon citrullination/carbamylation results in an ∼58 mM KCl retention decrease, while retention of deamidated products decreases slightly.
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Affiliation(s)
- Carina Villacrés
- Manitoba Centre for Proteomics and Systems Biology, Department of Internal Medicine, University of Manitoba, Winnipeg, MB R3E 3P4, Canada
| | - Victor Spicer
- Manitoba Centre for Proteomics and Systems Biology, Department of Internal Medicine, University of Manitoba, Winnipeg, MB R3E 3P4, Canada
| | - Oleg V Krokhin
- Manitoba Centre for Proteomics and Systems Biology, Department of Internal Medicine, University of Manitoba, Winnipeg, MB R3E 3P4, Canada.,Internal Medicine, University of Manitoba, Winnipeg, MB R3E 3P4, Canada
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27
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Wu CY, Yang HY, Luo SF, Lai JH. From Rheumatoid Factor to Anti-Citrullinated Protein Antibodies and Anti-Carbamylated Protein Antibodies for Diagnosis and Prognosis Prediction in Patients with Rheumatoid Arthritis. Int J Mol Sci 2021; 22:ijms22020686. [PMID: 33445768 PMCID: PMC7828258 DOI: 10.3390/ijms22020686] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/04/2021] [Accepted: 01/06/2021] [Indexed: 02/07/2023] Open
Abstract
Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease mainly involving synovial inflammation and articular bone destruction. RA is a heterogeneous disease with diverse clinical presentations, prognoses and therapeutic responses. Following the first discovery of rheumatoid factors (RFs) 80 years ago, the identification of both anti-citrullinated protein antibodies (ACPAs) and anti-carbamylated protein antibodies (anti-CarP Abs) has greatly facilitated approaches toward RA, especially in the fields of early diagnosis and prognosis prediction of the disease. Although these antibodies share many common features and can function synergistically to promote disease progression, they differ mechanistically and have unique clinical relevance. Specifically, these three RA associating auto-antibodies (autoAbs) all precede the development of RA by years. However, while the current evidence suggests a synergic effect of RF and ACPA in predicting the development of RA and an erosive phenotype, controversies exist regarding the additive value of anti-CarP Abs. In the present review, we critically summarize the characteristics of these autoantibodies and focus on their distinct clinical applications in the early identification, clinical manifestations and prognosis prediction of RA. With the advancement of treatment options in the era of biologics, we also discuss the relevance of these autoantibodies in association with RA patient response to therapy.
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Affiliation(s)
- Chao-Yi Wu
- Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 33303, Taiwan;
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Huang-Yu Yang
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
- Department of Nephrology, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Shue-Fen Luo
- Division of Allergy, Immunology, and Rheumatology, Department of Internal Medicine, Chang Gung Memorial Hospital, Chang Gung University, Taoyuan 333, Taiwan;
| | - Jenn-Haung Lai
- Division of Allergy, Immunology, and Rheumatology, Department of Internal Medicine, Chang Gung Memorial Hospital, Chang Gung University, Taoyuan 333, Taiwan;
- Graduate Institute of Medical Science, National Defense Medical Center, Taipei 114, Taiwan
- Correspondence: ; Tel.: +886-2-8791-8382; Fax: +886-2-8791-8382
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28
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Hefton A, Liang SY, Ni K, Carter V, Ukadike K, Lood C, Mustelin T. Autoantibodies against citrullinated serum albumin in patients with rheumatoid arthritis. J Transl Autoimmun 2020; 2:100023. [PMID: 32743509 PMCID: PMC7388351 DOI: 10.1016/j.jtauto.2019.100023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 11/04/2019] [Indexed: 11/27/2022] Open
Abstract
Rheumatoid arthritis (RA) is a chronic, potentially debilitating, inflammatory disease that primarily affects synovial joints. While the etiology of RA remains incompletely understood, it is clear that the disease is autoimmune in nature. A hallmark of RA is that the specific epitopes on self-antigens that are targeted by the immune system are often modified by arginine deimination, also referred to as citrullination. In fact, anti-citrullinated protein autoantibodies (ACPA) at high enough titers are diagnostic of RA and appear to have many different targets. Here, we report that RA patients have IgG autoantibodies that react with human serum albumin (HSA) when it had been citrullinated by protein arginine deiminase (PAD) 4, but not by PAD2. Unmodified albumin was not recognized by autoantibodies. In a cohort of 79 RA patients, 38% had anti-citrullinated HSA (anti-cit-HSA) reactivity above the cut-off of the average plus two standard deviations in a healthy subject cohort (n = 16). The titers of these autoantibodies correlated with ACPA status and seropositivity. There was also a trend toward correlation with the presence of radiographic joint erosions, but this did not reach statistical significance. Finally, patients with anti-cit-HSA were more frequently treated with biologics and combination regimens than patients without these autoantibodies. We conclude that ACPA directed against citrullinated albumin exist in a subset of RA patients. Because of the abundance of albumin, its modification by citrullination, as well as autoantibodies binding to it, may have deleterious consequences for the health of affected RA patients. Novel autoantigen in rheumatoid arthritis: citrullinated serum albumin. Anti-citrullinated albumin IgG autoantibodies correlate with clinical parameters. Even a low stoichiometry citrullination of the very abundant albumin may have health consequences. Use of poly(Gly, Lys, Tyr) for blocking to detect citrullinated proteins without high background.
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Affiliation(s)
- Amanda Hefton
- Division of Rheumatology, Department of Medicines, University of Washington, 750 Republican Street, Room E507, Seattle, WA 99108, United States
| | - Shu Ying Liang
- Division of Rheumatology, Department of Medicines, University of Washington, 750 Republican Street, Room E507, Seattle, WA 99108, United States
| | - Kathryn Ni
- Division of Rheumatology, Department of Medicines, University of Washington, 750 Republican Street, Room E507, Seattle, WA 99108, United States
| | - Victoria Carter
- Division of Rheumatology, Department of Medicines, University of Washington, 750 Republican Street, Room E507, Seattle, WA 99108, United States
| | - Kennedy Ukadike
- Division of Rheumatology, Department of Medicines, University of Washington, 750 Republican Street, Room E507, Seattle, WA 99108, United States
| | - Christian Lood
- Division of Rheumatology, Department of Medicines, University of Washington, 750 Republican Street, Room E507, Seattle, WA 99108, United States
| | - Tomas Mustelin
- Division of Rheumatology, Department of Medicines, University of Washington, 750 Republican Street, Room E507, Seattle, WA 99108, United States
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29
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Wu CY, Yang HY, Lai JH. Anti-Citrullinated Protein Antibodies in Patients with Rheumatoid Arthritis: Biological Effects and Mechanisms of Immunopathogenesis. Int J Mol Sci 2020; 21:ijms21114015. [PMID: 32512739 PMCID: PMC7312469 DOI: 10.3390/ijms21114015] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 05/30/2020] [Accepted: 06/02/2020] [Indexed: 12/11/2022] Open
Abstract
Individuals with high anti-citrullinated protein antibody (ACPA) titers have an increased risk of developing rheumatoid arthritis (RA). Although our knowledge of the generation and production of ACPAs has continuously advanced during the past decade, our understanding on the pathogenic mechanisms of how ACPAs interact with immune cells to trigger articular inflammation is relatively limited. Citrullination disorders drive the generation and maintenance of ACPAs, with profound clinical significance in patients with RA. The loss of tolerance to citrullinated proteins, however, is essential for ACPAs to exert their pathogenicity. N-linked glycosylation, cross-reactivity and the structural interactions of ACPAs with their citrullinated antigens further direct their biological functions. Although questions remain in the pathogenicity of ACPAs acting as agonists for a receptor-mediated response, immune complex (IC) formation, complement system activation, crystallizable fragment gamma receptor (FcγR) activation, cross-reactivity to joint cartilage and neutrophil extracellular trap (NET)-related mechanisms have all been suggested recently. This paper presents a critical review of the characteristics and possible biological effects and mechanisms of the immunopathogenesis of ACPAs in patients with RA.
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Affiliation(s)
- Chao-Yi Wu
- Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan;
- Chang Gung University, College of Medicine, Taoyuan 333, Taiwan;
| | - Huang-Yu Yang
- Chang Gung University, College of Medicine, Taoyuan 333, Taiwan;
- Department of Nephrology, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Jenn-Haung Lai
- Division of Allergy, Immunology, and Rheumatology, Department of Internal Medicine, Chang Gung Memorial Hospital, Chang Gung University, Taoyuan 333, Taiwan
- Graduate Institute of Medical Science, National Defense Medical Center, Taipei 114, Taiwan
- Correspondence: ; Tel.: +886-2-8791-8382; Fax: +886-2-8791-8382
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30
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Desclos-Theveniau M, Bonnaure-Mallet M, Meuric V. [Protein arginine deiminase of oral microbiome plays a causal role in the polyarthritis rheumatoid initiating]. Med Sci (Paris) 2020; 36:465-471. [PMID: 32452368 DOI: 10.1051/medsci/2020078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In the last decade, the association between the periodontitis and rheumatoid arthritis (RA) has been established, suggesting that oral microbiome plays a causal role by initiating this chronic autoimmune inflammatory disease of articulation. Both pathogenesis are similar in term of chronic inflammation, tissue breakdown and bone resorption. Molecular aspects have also revealed that citrullination, a post-translational modification catalyzed by peptidyl-arginine deiminases (PADs), is involved in both diseases. For RA, citrullinated proteins production leads to the synthesis the of anti-citrullinated protein antibodies triggering the loss of immune tolerance. In humans, five PADs have been identified. Recently, studies have found that only Porphyromonas species possess PAD. Thus, a major periodontal pathogen, Porphyromonas gingivalis, is able to generate citrullinated epitopes, and could consequently induce anti-citrullinated protein antibodies. In this review, citrullination process, periodontitis and RA are described to put them in relation with molecular, clinical and epidemiological studies establishing the association between periodontitis and RA.
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Affiliation(s)
- Marie Desclos-Theveniau
- Inserm, INRAE, Univ Rennes 1, CHU de Rennes, Nutrition, Métabolismes et Cancer, 2 avenue du professeur Léon Bernard, 35043 Rennes, France
| | - Martine Bonnaure-Mallet
- Inserm, INRAE, Univ Rennes 1, CHU de Rennes, Nutrition, Métabolismes et Cancer, 2 avenue du professeur Léon Bernard, 35043 Rennes, France
| | - Vincent Meuric
- Inserm, INRAE, Univ Rennes 1, CHU de Rennes, Nutrition, Métabolismes et Cancer, 2 avenue du professeur Léon Bernard, 35043 Rennes, France
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31
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Khatri S, Hansen J, Astakhova K. Antibodies to synthetic citrullinated peptide epitope correlate with disease activity and flares in rheumatoid arthritis. PLoS One 2020; 15:e0232010. [PMID: 32324839 PMCID: PMC7179858 DOI: 10.1371/journal.pone.0232010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 04/05/2020] [Indexed: 01/13/2023] Open
Abstract
Rheumatoid arthritis (RA), caused by the abnormal recognition of human joint cells by autoimmune antibodies, remains the world’s most prevalent autoimmune disease, with over five million people affected and as much as 4% of the population at risk of RA. To prevent rapid disease development, hormonal and anti-inflammatory therapies require fast and reliable RA diagnosis. However, difficulty in detecting early specific biomarkers for RA means that it is unclear when treatment needs to begin. Here, we combined synthesis of citrullinated peptide epitopes with molecular diagnostics to verify a new specific biomarker for early RA diagnosis and flare prediction. A fibrinogen-derived 21-amino-acid-long citrullinated peptide showed high reactivity toward autoantibodies in RA samples. Additionally, the level of antibodies to this epitope was elevated prior to flares. In contrast, other citrullinated protein variants had lower reactivity and poorer sensitivity to disease activity. In conclusion, fibrinogen-derived epitope E2 subjected to citrullination facilitated a reliable RA diagnosis with a strong correlation to disease activity. This is of a high value for the diagnosis and management of RA patients who respond poorly to treatment.
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Affiliation(s)
- Sangita Khatri
- Department of Chemistry, Technical University of Denmark, Kgs Lyngby, Denmark
| | - Jonas Hansen
- Department of Chemistry, Technical University of Denmark, Kgs Lyngby, Denmark
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Kira Astakhova
- Department of Chemistry, Technical University of Denmark, Kgs Lyngby, Denmark
- * E-mail:
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Li G, Young CH, Snow B, Christensen AO, Demoruelle MK, Nemmara VV, Thompson PR, Rothfuss HM, Cherrington BD. Identification and Characterization of the Lactating Mouse Mammary Gland Citrullinome. Int J Mol Sci 2020; 21:ijms21072634. [PMID: 32290104 PMCID: PMC7177251 DOI: 10.3390/ijms21072634] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/07/2020] [Accepted: 04/08/2020] [Indexed: 02/07/2023] Open
Abstract
Citrullination is a post-translational modification (PTM) in which positively charged peptidyl-arginine is converted into neutral peptidyl-citrulline by peptidylarginine deiminase (PAD or PADI) enzymes. The full protein citrullinome in many tissues is unknown. Herein, we used mass spectrometry and identified 107 citrullinated proteins in the lactation day 9 (L9) mouse mammary gland including histone H2A, α-tubulin, and β-casein. Given the importance of prolactin to lactation, we next tested if it stimulates PAD-catalyzed citrullination using mouse mammary epithelial CID-9 cells. Stimulation of CID-9 cells with 5 µg/mL prolactin for 10 min induced a 2-fold increase in histone H2A citrullination and a 4.5-fold increase in α-tubulin citrullination. We next investigated if prolactin-induced citrullination regulates the expression of lactation genes β-casein (Csn2) and butyrophilin (Btn1a1). Prolactin treatment for 12 h increased β-casein and butyrophilin mRNA expression; however, this increase was significantly inhibited by the pan-PAD inhibitor, BB-Cl-amidine (BB-ClA). We also examined the effect of tubulin citrullination on the overall polymerization rate of microtubules. Our results show that citrullinated tubulin had a higher maximum overall polymerization rate. Our work suggests that protein citrullination is an important PTM that regulates gene expression and microtubule dynamics in mammary epithelial cells.
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Affiliation(s)
- Guangyuan Li
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA; (G.L.); (C.H.Y.); (B.S.); (A.O.C.); (H.M.R.)
| | - Coleman H. Young
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA; (G.L.); (C.H.Y.); (B.S.); (A.O.C.); (H.M.R.)
| | - Bryce Snow
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA; (G.L.); (C.H.Y.); (B.S.); (A.O.C.); (H.M.R.)
| | - Amanda O. Christensen
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA; (G.L.); (C.H.Y.); (B.S.); (A.O.C.); (H.M.R.)
| | - M. Kristen Demoruelle
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, CO 80045, USA;
| | - Venkatesh V. Nemmara
- Department of Chemistry and Biochemistry, Rowan University, Glassboro, NJ 08028, USA;
| | - Paul R. Thompson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA;
| | - Heather M. Rothfuss
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA; (G.L.); (C.H.Y.); (B.S.); (A.O.C.); (H.M.R.)
| | - Brian D. Cherrington
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA; (G.L.); (C.H.Y.); (B.S.); (A.O.C.); (H.M.R.)
- Correspondence:
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Liu Y, Sun Y, Li S, Liu M, Qin X, Chen X, Lin Y. Tetrahedral Framework Nucleic Acids Deliver Antimicrobial Peptides with Improved Effects and Less Susceptibility to Bacterial Degradation. NANO LETTERS 2020; 20:3602-3610. [PMID: 32272018 DOI: 10.1021/acs.nanolett.0c00529] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Yuhao Liu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yue Sun
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Songhang Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Mengting Liu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xin Qin
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xingyu Chen
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yunfeng Lin
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Vogt LM, Kwasniewicz E, Talens S, Scavenius C, Bielecka E, Ekdahl KN, Enghild JJ, Mörgelin M, Saxne T, Potempa J, Blom AM. Apolipoprotein E Triggers Complement Activation in Joint Synovial Fluid of Rheumatoid Arthritis Patients by Binding C1q. THE JOURNAL OF IMMUNOLOGY 2020; 204:2779-2790. [PMID: 32253242 DOI: 10.4049/jimmunol.1900372] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 03/10/2020] [Indexed: 12/11/2022]
Abstract
We identified apolipoprotein E (ApoE) as one of the proteins that are found in complex with complement component C4d in pooled synovial fluid of rheumatoid arthritis (RA) patients. Immobilized human ApoE activated both the classical and the alternative complement pathways. In contrast, ApoE in solution demonstrated an isoform-dependent inhibition of hemolysis and complement deposition at the level of sC5b-9. Using electron microscopy imaging, we confirmed that ApoE interacts differently with C1q depending on its context; surface-bound ApoE predominantly bound C1q globular heads, whereas ApoE in a solution favored the hinge/stalk region of C1q. As a model for the lipidated state of ApoE in lipoprotein particles, we incorporated ApoE into phosphatidylcholine/phosphatidylethanolamine liposomes and found that the presence of ApoE on liposomes increased deposition of C1q and C4b from serum when analyzed using flow cytometry. In addition, posttranslational modifications associated with RA, such as citrullination and oxidation, reduced C4b deposition, whereas carbamylation enhanced C4b deposition on immobilized ApoE. Posttranslational modification of ApoE did not alter C1q interaction but affected binding of complement inhibitors factor H and C4b-binding protein. This suggests that changed ability of C4b to deposit on modified ApoE may play an important role. Our data show that posttranslational modifications of ApoE alter its interactions with complement. Moreover, ApoE may play different roles in the body depending on its solubility, and in diseased states such as RA, deposited ApoE may induce local complement activation rather than exert its typical role of inhibition.
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Affiliation(s)
- Leonie M Vogt
- Division of Medical Protein Chemistry, Department of Translational Medicine, Lund University, 21428 Malmö, Sweden
| | - Ewa Kwasniewicz
- Division of Medical Protein Chemistry, Department of Translational Medicine, Lund University, 21428 Malmö, Sweden
| | - Simone Talens
- Division of Medical Protein Chemistry, Department of Translational Medicine, Lund University, 21428 Malmö, Sweden
| | - Carsten Scavenius
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Ewa Bielecka
- Malopolska Centre of Biotechnology, Jagiellonian University, PL-30-387 Kraków, Poland
| | - Kristina N Ekdahl
- Rudbeck Laboratory, Department of Immunology, Genetics, and Pathology, Uppsala University, 751 85 Uppsala, Sweden.,Linnaeus Centre for Biomaterials Chemistry, Linnaeus University, 391 82 Kalmar, Sweden
| | - Jan J Enghild
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Matthias Mörgelin
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, 221 84 Lund, Sweden
| | - Tore Saxne
- Department of Clinical Sciences Lund, Section of Rheumatology, Lund University, S-22185 Lund, Sweden
| | - Jan Potempa
- Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland; and.,Department of Oral Immunity and Infectious Diseases, University of Louisville School of Dentistry, Louisville, KY 40202
| | - Anna M Blom
- Division of Medical Protein Chemistry, Department of Translational Medicine, Lund University, 21428 Malmö, Sweden;
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Fert-Bober J, Darrah E, Andrade F. Insights into the study and origin of the citrullinome in rheumatoid arthritis. Immunol Rev 2019; 294:133-147. [PMID: 31876028 DOI: 10.1111/imr.12834] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 12/08/2019] [Indexed: 12/11/2022]
Abstract
The presence of autoantibodies and autoreactive T cells to citrullinated proteins and citrullinating enzymes in patients with rheumatoid arthritis (RA), together with the accumulation of citrullinated proteins in rheumatoid joints, provides substantial evidence that dysregulated citrullination is a hallmark feature of RA. However, understanding mechanisms that dysregulate citrullination in RA has important challenges. Citrullination is a normal process in immune and non-immune cells, which is likely activated by different conditions (eg, inflammation) with no pathogenic consequences. In a complex inflammatory environment such as the RA joint, unique strategies are therefore required to dissect specific mechanisms involved in the abnormal production of citrullinated proteins. Here, we will review current models of citrullination in RA and discuss critical components that, in our view, are relevant to understanding the accumulation of citrullinated proteins in the RA joint, collectively referred to as the RA citrullinome. In particular, we will focus on potential caveats in the study of citrullination in RA and will highlight methods to precisely detect citrullinated proteins in complex biological samples, which is a confirmatory approach to mechanistically link the RA citrullinome with unique pathogenic pathways in RA.
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Affiliation(s)
- Justyna Fert-Bober
- The Smidt Heart Institute, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California
| | - Erika Darrah
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Felipe Andrade
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
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Wang C, Wang Q, Li R, Qin J, Song L, Zhang Q, Liu M, Chen J, Wang C. LTF, PRTN3, and MNDA in Synovial Fluid as Promising Biomarkers for Periprosthetic Joint Infection: Identification by Quadrupole Orbital-Trap Mass Spectrometry. J Bone Joint Surg Am 2019; 101:2226-2234. [PMID: 31644522 DOI: 10.2106/jbjs.18.01483] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Diagnosing periprosthetic joint infection (PJI) requires various laboratory and clinical criteria. The purpose of this study was to explore novel biomarkers that could rapidly diagnose PJI with high accuracy. METHODS In this retrospective study of prospectively collected samples, 50 synovial fluid aspirates, 20 from the hip and 30 from the knee, were collected before surgery; 25 of the patients were diagnosed as having aseptic loosening (non-PJI) and 25, as having PJI according to the Musculoskeletal Infection Society criteria. A quadrupole orbital-trap mass spectrometry (MS) instrument was used to compare expression of proteins in patients with and without PJI. Proteins that were most efficacious for diagnosis of PJI were then determined using prediction analysis of microarray software and a random forest model. The most promising proteins were selected, and altered expression of these selected proteins was verified by ELISA (enzyme-linked immunosorbent assay) in an extended sample cohort. RESULTS A total of 256 proteins were significantly upregulated (≥3.0-fold) and 14 proteins were downregulated in synovial fluid of patients with PJI compared with patients without PJI. The 3 most promising proteins were lactoferrin (LTF), polymorphonuclear leukocyte serine protease 3 (PRTN3), and myeloid nuclear differentiation antigen (MNDA). When MS was used for diagnosis of PJI, the area under the curve was 0.9888 for LTF, 0.9488 for PRTN3, and 0.9632 for MNDA. ELISA results verified that LTF, MNDA, and PRTN3 were sensitive, while LTF and MNDA were specific, for diagnosis of PJI. CONCLUSIONS This proteomic study identified a previously noted protein and 2 novel candidate proteins as promising synovial fluid biomarkers for PJI diagnosis, and they should be further validated in future clinical trials. LEVEL OF EVIDENCE Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.
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Affiliation(s)
- Chi Wang
- Departments of Clinical Laboratory Medicine (Chi Wang, Q.W., Q.Z., and Chengbin Wang) and Orthopedics (Q.W., R.L., and J.C.), People's Liberation Army General Hospital, Beijing, People's Republic of China
| | - Qi Wang
- Departments of Clinical Laboratory Medicine (Chi Wang, Q.W., Q.Z., and Chengbin Wang) and Orthopedics (Q.W., R.L., and J.C.), People's Liberation Army General Hospital, Beijing, People's Republic of China
| | - Rui Li
- Departments of Clinical Laboratory Medicine (Chi Wang, Q.W., Q.Z., and Chengbin Wang) and Orthopedics (Q.W., R.L., and J.C.), People's Liberation Army General Hospital, Beijing, People's Republic of China
| | - Jun Qin
- State Key Laboratory of Proteomics, National Center for Protein Sciences (The PHOENIX Center), Beijing Proteome Research Center, Beijing, People's Republic of China
| | - Lei Song
- State Key Laboratory of Proteomics, National Center for Protein Sciences (The PHOENIX Center), Beijing Proteome Research Center, Beijing, People's Republic of China
| | - Qian Zhang
- Departments of Clinical Laboratory Medicine (Chi Wang, Q.W., Q.Z., and Chengbin Wang) and Orthopedics (Q.W., R.L., and J.C.), People's Liberation Army General Hospital, Beijing, People's Republic of China
| | - Mingwei Liu
- State Key Laboratory of Proteomics, National Center for Protein Sciences (The PHOENIX Center), Beijing Proteome Research Center, Beijing, People's Republic of China
| | - Jiying Chen
- Departments of Clinical Laboratory Medicine (Chi Wang, Q.W., Q.Z., and Chengbin Wang) and Orthopedics (Q.W., R.L., and J.C.), People's Liberation Army General Hospital, Beijing, People's Republic of China
| | - Chengbin Wang
- Departments of Clinical Laboratory Medicine (Chi Wang, Q.W., Q.Z., and Chengbin Wang) and Orthopedics (Q.W., R.L., and J.C.), People's Liberation Army General Hospital, Beijing, People's Republic of China
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Zheng Z, Mergaert AM, Fahmy LM, Bawadekar M, Holmes CL, Ong IM, Bridges AJ, Newton MA, Shelef MA. Disordered Antigens and Epitope Overlap Between Anti-Citrullinated Protein Antibodies and Rheumatoid Factor in Rheumatoid Arthritis. Arthritis Rheumatol 2019; 72:262-272. [PMID: 31397047 DOI: 10.1002/art.41074] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 08/06/2019] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Anti-citrullinated protein antibodies (ACPAs) and rheumatoid factor (RF) are commonly present in rheumatoid arthritis (RA) without a clear rationale for their coexistence. Moreover, autoantibodies develop against proteins with different posttranslational modifications and native proteins without obvious unifying characteristics of the antigens. We undertook this study to broadly evaluate autoantibody binding in seronegative and seropositive RA to identify novel features of reactivity. METHODS An array was created using a total of 172,828 native peptides, citrulline-containing peptides, and homocitrulline-containing peptides derived primarily from proteins citrullinated in the rheumatoid joint. IgG and IgM binding to peptides were compared between cyclic citrullinated peptide (CCP)-positive RF+, CCP+RF-, CCP-RF+, and CCP-RF- serum from RA patients (n = 48) and controls (n = 12). IgG-bound and endogenously citrullinated peptides were analyzed for amino acid patterns and predictors of intrinsic disorder, i.e., unstable 3-dimensional structure. Binding to IgG-derived peptides was specifically evaluated. Enzyme-linked immunosorbent assay confirmed key results. RESULTS Broadly, CCP+RF+ patients had high citrulline-specific IgG binding to array peptides and CCP+RF- and CCP-RF+ patients had modest citrulline-specific IgG binding (median Z scores 3.02, 1.42, and 0.75, respectively; P < 0.0001). All RA groups had low homocitrulline-specific binding. CCP+RF+ patients had moderate IgG binding to native peptides (median Z score 2.38; P < 0.0001). The highest IgG binding was to citrulline-containing peptides, irrespective of protein identity, especially if citrulline was adjacent to glycine or serine, motifs also seen in endogenous citrullination in the rheumatoid joint. Highly bound peptides had multiple features predictive of disorder. IgG from CCP+RF+ patients targeted citrulline-containing IgG-derived peptides. CONCLUSION Disordered antigens, which are frequently citrullinated, and common epitopes for ACPAs and RF are potentially unifying features for RA autoantibodies.
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Affiliation(s)
| | | | | | | | | | - Irene M Ong
- University of Wisconsin-Madison and University of Wisconsin Carbone Comprehensive Cancer Center
| | - Alan J Bridges
- University of Wisconsin-Madison and William S. Middleton Memorial Veterans Hospital
| | | | - Miriam A Shelef
- University of Wisconsin-Madison and William S. Middleton Memorial Veterans Hospital
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Rantapää Dahlqvist S, Andrade F. Individuals at risk of seropositive rheumatoid arthritis: the evolving story. J Intern Med 2019; 286:627-643. [PMID: 31562671 PMCID: PMC6878216 DOI: 10.1111/joim.12980] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The aetiology of the autoimmune disease rheumatoid arthritis (RA) involves a complex interplay between genetic and environmental factors that initiate many years before the onset of clinical symptoms. These interactions likely include both protective and susceptibility factors which together determine the risk of developing RA. More than 100 susceptibility loci have been linked to RA. The strongest association is with HLA-DRB1 alleles encoding antigen presenting molecules containing a unique sequence in the peptide-binding grove called the 'shared epitope'. Female sex, infections during childhood, lifestyle habits (e.g. smoking and diet) and distinct microbial agents, amongst many others, are interacting risk factors thought to contribute to RA pathogenesis by dysregulating the immune system in individuals with genetic susceptibility. Interestingly, patients with RA develop autoantibodies many years before the clinical onset of disease, providing strong evidence that the lack of tolerance to arthritogenic antigens is amongst the earliest events in the initiation of seropositive RA. Here, we will discuss the clinical and mechanistic evidence surrounding the role of different environmental and genetic factors in the phases leading to the production of autoantibodies and the initiation of symptomatic RA. Understanding this complexity is critical in order to develop tools to identify drivers of disease initiation and propagation and to develop preventive therapeutics.
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Affiliation(s)
- S Rantapää Dahlqvist
- Institution of Public Health and Clinical Medicine/Rheumatology, Umeå University, Umeå, Sweden
| | - F Andrade
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Li B, Li P, Bi L. Iguratimod dose dependently inhibits the expression of citrullinated proteins and peptidylarginine deiminases 2 and 4 in neutrophils from rheumatoid arthritis patients. Clin Rheumatol 2019; 39:899-907. [PMID: 31758423 DOI: 10.1007/s10067-019-04835-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 09/29/2019] [Accepted: 10/31/2019] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Anti-citrullinated protein antibodies (ACPAs) play an important role in rheumatoid arthritis (RA). Citrullinated proteins (CPs), which are produced by post-translational modification via peptidylarginine deiminase (PAD), are the target antigen of ACPAs and promote the generation thereof. Herein, we investigated whether iguratimod (IGU) affects the generation of CPs via PAD. METHODS Neutrophils and peripheral blood mononuclear cells (PBMCs) were isolated from three patients diagnosed with RA and treated with various concentrations of IGU, methotrexate (MTX), or dexamethasone (DXM) or without any drugs as a control for 8 h. The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-8 in culture supernatants were tested by ELISA. CPs were measured by western blot, and the expression of PAD2 and PAD4 in cells was detected by qRT-PCR and western blot. RESULTS PAD2 and PAD4 expressions in neutrophils but not in PBMCs were decreased by IGU at both the protein and mRNA levels (P < 0.05). CP expression in neutrophils but not in PBMCs was also inhibited by IGU. The inhibitory effect of IGU was dose-dependent. IGU, MTX, and DXM dose dependently decreased the secretion of TNF-α, IL-1β, IL-6, and IL-8 in neutrophils and PBMCs (P < 0.05); the inhibitory effect of IGU was not significantly different from that of MTX and DXM. CONCLUSIONS IGU inhibited the expression of CPs by downregulating PADs in neutrophils from RA patients, and the effect was comparable to that of MTX and DXM at appropriate concentrations. These findings may provide guidance for more appropriate treatment of RA.Key Points• Iguratimod inhibited citrullinated protein expression in neutrophils from rheumatoid arthritis patients similarly to methotrexate and dexamethasone at appropriate concentrations.• The inhibitory effect was mediated by downregulation of peptidylarginine deiminases, providing insight into the mechanism of iguratimod as a treatment for rheumatoid arthritis.• This study may guide rheumatoid arthritis treatment and facilitate identification of other therapeutic targets.
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Affiliation(s)
- Bingtong Li
- Department of Rheumatology and Immunology, China-Japan Union Hospital of Jilin University, 126 Xiantai Street, Changchun, 130033, China
| | - Ping Li
- Department of Rheumatology and Immunology, China-Japan Union Hospital of Jilin University, 126 Xiantai Street, Changchun, 130033, China
| | - Liqi Bi
- Department of Rheumatology and Immunology, China-Japan Union Hospital of Jilin University, 126 Xiantai Street, Changchun, 130033, China.
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Martinez-Prat L, Palterer B, Vitiello G, Parronchi P, Robinson WH, Mahler M. Autoantibodies to protein-arginine deiminase (PAD) 4 in rheumatoid arthritis: immunological and clinical significance, and potential for precision medicine. Expert Rev Clin Immunol 2019; 15:1073-1087. [DOI: 10.1080/1744666x.2020.1668778] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Laura Martinez-Prat
- Research and Development, Inova Diagnostics, San Diego, CA, USA
- Department of Experimental Science, Francisco de Vitoria University, Madrid, Spain
| | - Boaz Palterer
- specialist in Allergy and Clinical Immunology, Experimental and Clinical Medicine Department, University of Florence, Florence, Italy
| | - Gianfranco Vitiello
- resident in Allergy and Clinical Immunology, Experimental and Clinical Medicine Department, University of Florence, Florence, Italy
| | - Paola Parronchi
- (Allergy and Clinical Immunology), Laboratory Head, Experimental and Clinical Medicine Department, University of Florence, Florence, Italy
| | - William H. Robinson
- (Immunology and Rheumatology), Division of Immunology and Rheumatology, Stanford University, Stanford, CA, USA
- Geriatric Research Education and Clinical [GRECC] Division, VA Palo Alto Health Care System, Palo Alto, CA, USA
| | - Michael Mahler
- Research and Development, Inova Diagnostics, San Diego, CA, USA
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Gómez-Bañuelos E, Mukherjee A, Darrah E, Andrade F. Rheumatoid Arthritis-Associated Mechanisms of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. J Clin Med 2019; 8:jcm8091309. [PMID: 31454946 PMCID: PMC6780899 DOI: 10.3390/jcm8091309] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 08/20/2019] [Accepted: 08/21/2019] [Indexed: 12/19/2022] Open
Abstract
Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology characterized by immune-mediated damage of synovial joints and antibodies to citrullinated antigens. Periodontal disease, a bacterial-induced inflammatory disease of the periodontium, is commonly observed in RA and has implicated periodontal pathogens as potential triggers of the disease. In particular, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans have gained interest as microbial candidates involved in RA pathogenesis by inducing the production of citrullinated antigens. Here, we will discuss the clinical and mechanistic evidence surrounding the role of these periodontal bacteria in RA pathogenesis, which highlights a key area for the treatment and preventive interventions in RA.
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Affiliation(s)
- Eduardo Gómez-Bañuelos
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA
| | - Amarshi Mukherjee
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA
| | - Erika Darrah
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA
| | - Felipe Andrade
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
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Sharma M, Damgaard D, Senolt L, Svensson B, Bay-Jensen AC, Nielsen CH, Hägglund P. Expanding the citrullinome of synovial fibrinogen from rheumatoid arthritis patients. J Proteomics 2019; 208:103484. [PMID: 31408709 DOI: 10.1016/j.jprot.2019.103484] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 08/06/2019] [Accepted: 08/09/2019] [Indexed: 12/22/2022]
Abstract
Citrullination is a post-translational protein modification, which is associated with inflammation in general and is thought to play an important pathogenic role in rheumatoid arthritis (RA). Here a mass spectrometry-based proteomics approach was applied to identify citrullination sites in synovial fluid fibrinogen from four RA patients. In general, high disease activity correlated with increased number of identified citrullination sites and higher relative citrulline occupancy. Altogether, 23 sites were identified, of which 9 have not been previously reported to be citrullinated in vivo. Citrullination at site α84, α123, α129, α547, α573, α591, β334 and γ134 was identified in more than one patient, and these positions were therefore regarded as hotspots. Following citrullination of fibrinogen in vitro using human recombinant peptidylarginine deiminase 2 (PAD2), a total of 46 citrullination sites were identified, including 6 hitherto unreported in vitro citrullination sites. Twenty-two out of the 23 citrullination sites identified in vivo were also detected in vitro, supporting the validity of the identifications. SIGNIFICANCE: This work provides information about previously uncharacterized citrullination sites in synovial fluid fibrinogen from rheumatoid arthritis patients. Detection of these novel citrullination sites may prove to have diagnostic or prognostic value in RA and enhance our understanding of the immune pathogenesis.
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Affiliation(s)
- Mandvi Sharma
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Dres Damgaard
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark; Section for Periodontology, Microbiology and Community Dentistry, Department of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ladislav Senolt
- Institute of Rheumatology and Department of Rheumatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Birte Svensson
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | | | - Claus Henrik Nielsen
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark; Section for Periodontology, Microbiology and Community Dentistry, Department of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Per Hägglund
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark.
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Nemtsova MV, Zaletaev DV, Bure IV, Mikhaylenko DS, Kuznetsova EB, Alekseeva EA, Beloukhova MI, Deviatkin AA, Lukashev AN, Zamyatnin AA. Epigenetic Changes in the Pathogenesis of Rheumatoid Arthritis. Front Genet 2019; 10:570. [PMID: 31258550 PMCID: PMC6587113 DOI: 10.3389/fgene.2019.00570] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 05/31/2019] [Indexed: 01/06/2023] Open
Abstract
Rheumatoid arthritis (RA) is a systemic autoimmune disease that affects about 1% of the world’s population. The etiology of RA remains unknown. It is considered to occur in the presence of genetic and environmental factors. An increasing body of evidence pinpoints that epigenetic modifications play an important role in the regulation of RA pathogenesis. Epigenetics causes heritable phenotype changes that are not determined by changes in the DNA sequence. The major epigenetic mechanisms include DNA methylation, histone proteins modifications and changes in gene expression caused by microRNAs and other non-coding RNAs. These modifications are reversible and could be modulated by diet, drugs, and other environmental factors. Specific changes in DNA methylation, histone modifications and abnormal expression of non-coding RNAs associated with RA have already been identified. This review focuses on the role of these multiple epigenetic factors in the pathogenesis and progression of the disease, not only in synovial fibroblasts, immune cells, but also in the peripheral blood of patients with RA, which clearly shows their high diagnostic potential and promising targets for therapy in the future.
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Affiliation(s)
- Marina V Nemtsova
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.,Laboratory of Epigenetics, Research Centre for Medical Genetics, Moscow, Russia
| | - Dmitry V Zaletaev
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.,Laboratory of Epigenetics, Research Centre for Medical Genetics, Moscow, Russia
| | - Irina V Bure
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Dmitry S Mikhaylenko
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.,Laboratory of Epigenetics, Research Centre for Medical Genetics, Moscow, Russia
| | - Ekaterina B Kuznetsova
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.,Laboratory of Epigenetics, Research Centre for Medical Genetics, Moscow, Russia
| | - Ekaterina A Alekseeva
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.,Laboratory of Epigenetics, Research Centre for Medical Genetics, Moscow, Russia
| | - Marina I Beloukhova
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Andrei A Deviatkin
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Alexander N Lukashev
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.,Martsinovsky Institute of Medical Parasitology, Tropical and Vector Borne Diseases, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Andrey A Zamyatnin
- Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.,A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
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44
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Jung N, Bueb JL, Tolle F, Bréchard S. Regulation of neutrophil pro-inflammatory functions sheds new light on the pathogenesis of rheumatoid arthritis. Biochem Pharmacol 2019; 165:170-180. [PMID: 30862503 DOI: 10.1016/j.bcp.2019.03.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 03/07/2019] [Indexed: 02/08/2023]
Abstract
For more than two centuries now, rheumatoid arthritis (RA) is under investigation intending to discover successful treatment. Despite decades of scientific advances, RA is still representing a challenge for contemporary medicine. Current drug therapies allow to improve significantly the quality of life of RA patients; however, they are still insufficient to reverse tissue injury and are often generating side-effects. The difficulty arises from the considerable fluctuation of the clinical course of RA among patients, making the predictive prognosis difficult. More and more studies underline the profound influence of the neutrophil multifaceted functions in the pathogenesis of RA. This renewed interest in the complexity of neutrophil functions in RA offers new exciting opportunities for valuable therapeutic targets as well as for safe and well-tolerated RA treatments. In this review, we aim to update the recent findings on the multiple facets of neutrophils in RA, in particular their impact in promoting the RA-based inflammation through the release of the cytokine-like S100A8/A9 protein complex, as well as the importance of NETosis in the disease progression and development. Furthermore, we delve into the complex question of neutrophil heterogeneity and plasticity and discuss the emerging role of miRNAs and epigenetic markers influencing the inflammatory response of neutrophils in RA and how they could constitute the starting point for novel attractive targets in RA therapy.
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Affiliation(s)
- N Jung
- Life Sciences Research Unit, Immune Cells and Inflammatory Diseases group, University of Luxembourg, 6 Avenue du Swing, L-4367 Belvaux, Luxembourg
| | - J-L Bueb
- Life Sciences Research Unit, Immune Cells and Inflammatory Diseases group, University of Luxembourg, 6 Avenue du Swing, L-4367 Belvaux, Luxembourg
| | - F Tolle
- Life Sciences Research Unit, Immune Cells and Inflammatory Diseases group, University of Luxembourg, 6 Avenue du Swing, L-4367 Belvaux, Luxembourg
| | - S Bréchard
- Life Sciences Research Unit, Immune Cells and Inflammatory Diseases group, University of Luxembourg, 6 Avenue du Swing, L-4367 Belvaux, Luxembourg.
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45
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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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Raj Christian SD, Thirugnanasambantham K, Islam MIH, Sudalaimuthu MK, Sundaram S, Ashok G, Senthilkumar V, Muralidaran S, Subramanian S. Identification of Expressed miRNAs in Human Rheumatoid Arthritis Using Computational Approach - Discovery of a New miR-7167 from Human. Microrna 2018; 8:147-154. [PMID: 30514198 DOI: 10.2174/2211536608666181204111438] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 10/08/2018] [Accepted: 11/22/2018] [Indexed: 01/03/2023]
Abstract
BACKGROUND Rheumatoid Arthritis (RA) is a chronic inflammatory and autoimmune disease leading to bones and joints destruction. It is one of the major causes of lifetime disability and mortality among humans in the developing and developed countries. It was evident that epigenetic dysregulation is related to the pathogenesis of RA. MicroRNAs (miRNAs) are small non-coding RNAs that are epigenetic regulators for diverse biological processes and also provided novel molecular insights in the formation of arthritis. OBJECTIVE The influences of miRNAs in the alteration of gene regulation during the pathogenesis of arthritis were exposed in recent years. METHOD The computational approach to identify miRNA through EST-based homology is more powerful, economical and time-efficient. In this study, we applied EST-based homology search to identify miRNAs responsible for the development of arthritis in human beings. RESULTS Our study on 36519 ESTs in human RA condition revealed the expression of four miRNAs, HSA-miR-198, HSA-miR-4647, has-miR-7167-5p and has-miR-7167-3p. The present study is the first report about has-miR-7167 that was homologous to Macaca mulatta. CONCLUSION The predicted targets of these identified miRNAs revealed many biological functions in the pathogenesis of RA. Further elaborated studies on these miRNAs will help to understand their function in the development of RA and the use of miRNAs as therapeutic targets in the future.
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Affiliation(s)
- Simon Durai Raj Christian
- Department of Pathology, Sri Ramachandra Medical College and Research Institute, Porur, Chennai, India
| | | | - Mohamed Ibrahim Hairul Islam
- Pondicherry Centre for Biological Science and Educational Trust, Jawahar Nagar, Pondicherry, India.,Department of Biotechnology, Karpaga Vinayaga College of Engineering and Technology, Tamil Nadu, India
| | | | - Sandhya Sundaram
- Department of Pathology, Sri Ramachandra Medical College and Research Institute, Porur, Chennai, India
| | - Ganapathy Ashok
- Pondicherry Centre for Biological Science and Educational Trust, Jawahar Nagar, Pondicherry, India
| | - Venugopal Senthilkumar
- Pondicherry Centre for Biological Science and Educational Trust, Jawahar Nagar, Pondicherry, India
| | - Senguttuvan Muralidaran
- Department of Biotechnology, A.V.C. College (Autonomous), Mannampandal, Mayiladuthurai, Tamil Nadu, India
| | - Saravanan Subramanian
- Pondicherry Centre for Biological Science and Educational Trust, Jawahar Nagar, Pondicherry, India
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47
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Zhou Y, An LL, Chaerkady R, Mittereder N, Clarke L, Cohen TS, Chen B, Hess S, Sims GP, Mustelin T. Evidence for a direct link between PAD4-mediated citrullination and the oxidative burst in human neutrophils. Sci Rep 2018; 8:15228. [PMID: 30323221 PMCID: PMC6189209 DOI: 10.1038/s41598-018-33385-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 09/26/2018] [Indexed: 01/14/2023] Open
Abstract
Neutrophils are critical for the defense against pathogens, in part through the extrusion of extracellular DNA traps, phagocytosis, and the production of reactive oxygen species. Neutrophils may also play an important role in the pathogenesis of rheumatoid arthritis (RA) through the activation of protein arginine deiminases (PADs) that citrullinate proteins that subsequently act as autoantigens. We report that PAD4 is physically associated with the cytosolic subunits of the oxidative burst machinery, p47phox (also known as neutrophil cytosol factor 1, NCF1) and p67phox (NCF2). Activation of PAD4 by membranolytic insults that result in high levels of intracellular calcium (higher than physiological neutrophil activation) leads to rapid citrullination of p47phox/NCF1 and p67phox/NCF2, as well as their dissociation from PAD4. This dissociation prevents the assembly of an active NADPH oxidase complex and an oxidative burst in neutrophils stimulated by phorbol-ester or immune complexes. In further support of a substrate-to-inactive enzyme interaction, small-molecule PAD inhibitors also disrupt the PAD4-NCF complex and reduce oxidase activation and phagocytic killing of Staphylococcus aureus. This novel role of PAD4 in the regulation of neutrophil physiology suggests that targeting PAD4 with active site inhibitors for the treatment of RA may have a broader impact on neutrophil biology than just inhibition of citrullination.
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Affiliation(s)
- Yebin Zhou
- Department of Respiratory, Inflammation, and Autoimmunity, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States
| | - Ling-Ling An
- Department of Respiratory, Inflammation, and Autoimmunity, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States
| | - Raghothama Chaerkady
- Antibody Discovery and Protein Engineering, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States
| | - Nanette Mittereder
- Department of Respiratory, Inflammation, and Autoimmunity, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States
| | - Lori Clarke
- Antibody Discovery and Protein Engineering, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States
| | - Taylor S Cohen
- Department of Microbial Sciences, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States
| | - Bo Chen
- Department of Respiratory, Inflammation, and Autoimmunity, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States
| | - Sonja Hess
- Antibody Discovery and Protein Engineering, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States
| | - Gary P Sims
- Department of Respiratory, Inflammation, and Autoimmunity, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States.
| | - Tomas Mustelin
- Department of Respiratory, Inflammation, and Autoimmunity, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878, United States. .,Division of Rheumatology, School of Medicine, University of Washington, 750 Republican Street, Seattle, WA98109, United States.
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48
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Damgaard D, Bawadekar M, Senolt L, Stensballe A, Shelef MA, Nielsen CH. Relative efficiencies of peptidylarginine deiminase 2 and 4 in generating target sites for anti-citrullinated protein antibodies in fibrinogen, alpha-enolase and histone H3. PLoS One 2018; 13:e0203214. [PMID: 30161253 PMCID: PMC6117052 DOI: 10.1371/journal.pone.0203214] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 08/16/2018] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE Peptidylarginine deiminase 2 (PAD2) and PAD4 are expressed in the synovium of rheumatoid arthritis (RA) patients and catalyze citrullination of arginine residues in proteins targeted by anti-citrullinated protein antibodies (ACPAs). Little is known about the relative importance of PAD2 and PAD4 in generating citrullinated self-antigens. Here we investigate the ability of PAD2 and PAD4 to generate citrullinated targets for ACPAs in four human proteins. METHODS Synovial fluid (SF) and plasma were collected from 42 RA patients. Human fibrinogen, human alpha-enolase (ENO1), human histone H3, and human serum albumin (HSA) were citrullinated in vitro by PAD2 or PAD4. The total degree of citrullination was determined using the anti-modified citrulline approach. Antibody binding to native and citrullinated proteins was measured by ELISA. RESULTS ACPAs within pooled SF from multiple RA patients reacted equally well with, and cross-reacted with, PAD2- and PAD4-citrullinated fibrinogen. ACPAs from most individual patient SF and plasma samples bound equally well to PAD2- and PAD4-citrullinated fibrinogen or ENO1. When histone H3 was used as target, PAD4 was generally superior in generating epitopes recognized by ACPAs. No binding to citrullinated HSA was observed. CONCLUSION In most patients, PAD2 and PAD4 are equally efficient in generating citrullinated target sites for ACPAs in fibrinogen and ENO1. The binding of autoantibodies to histone H3 was generally higher after citrullination with PAD4 than with PAD2. Citrullinated HSA is not a target for ACPAs.
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Affiliation(s)
- Dres Damgaard
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Section for Periodontology, Microbiology and Community Dentistry, Department of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- * E-mail:
| | - Mandar Bawadekar
- Department of Medicine, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Ladislav Senolt
- Institute of Rheumatology and Department of Rheumatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Allan Stensballe
- Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Miriam A. Shelef
- Department of Medicine, University of Wisconsin, Madison, Wisconsin, United States of America
- William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin, United States of America
| | - Claus H. Nielsen
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Section for Periodontology, Microbiology and Community Dentistry, Department of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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49
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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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50
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The Rheumatoid Arthritis-Associated Citrullinome. Cell Chem Biol 2018; 25:691-704.e6. [PMID: 29628436 DOI: 10.1016/j.chembiol.2018.03.002] [Citation(s) in RCA: 146] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 12/14/2017] [Accepted: 02/28/2018] [Indexed: 01/12/2023]
Abstract
Increased protein citrullination is linked to various diseases including rheumatoid arthritis (RA), lupus, and cancer. Citrullinated autoantigens, a hallmark of RA, are recognized by anti-citrullinated protein antibodies (ACPAs) which are used to diagnose RA. ACPA-recognizing citrullinated enolase, vimentin, keratin, and filaggrin are also pathogenic. Here, we used a chemoproteomic approach to define the RA-associated citrullinome. The identified proteins include numerous serine protease inhibitors (Serpins), proteases and metabolic enzymes. We demonstrate that citrullination of antiplasmin, antithrombin, t-PAI, and C1 inhibitor (P1-Arg-containing Serpins) abolishes their ability to inhibit their cognate proteases. Citrullination of nicotinamide N-methyl transferase (NNMT) also abolished its methyltransferase activity. Overall, these data advance our understanding of the roles of citrullination in RA and suggest that extracellular protein arginine deiminase (PAD) activity can modulate protease activity with consequent effects on Serpin-regulated pathways. Moreover, our data suggest that inhibition of extracellular PAD activity will be therapeutically relevant.
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