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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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2
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Xu M, Du R, Xing W, Chen X, Wan J, Wang S, Xiong L, Nandakumar KS, Holmdahl R, Geng H. Platelets derived citrullinated proteins and microparticles are potential autoantibodies ACPA targets in RA patients. Front Immunol 2023; 14:1084283. [PMID: 36761728 PMCID: PMC9902922 DOI: 10.3389/fimmu.2023.1084283] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 01/12/2023] [Indexed: 01/25/2023] Open
Abstract
Citrullinated neoepitopes have emerged as key triggers of autoantibodies anti-citrullinated protein antibodies (ACPA) synthesis in rheumatoid arthritis (RA) patients. Apart from their critical role in homeostasis and thrombosis, platelets have a significant contribution to inflammation as well. Although anuclear in nature, platelets have an intricate post-translational modification machinery. Till now, citrullination in platelets and its contribution to trigger autoantibodies ACPA production in RA is an unexplored research direction. Herein, we investigated the expression of peptidylarginine deiminase (PAD) enzymes and citrullinated proteins/peptides in the human platelets and platelet derived microparticles (PDP). Both PAD4 mRNA and protein, but not the other PAD isoforms, are detectable in the human platelets. With a strict filtering criterion,108 citrullination sites present on 76 proteins were identified in the human platelets, and 55 citrullinated modifications present on 37 different proteins were detected in the PDPs. Among them, some are well-known citrullinated autoantigens associated with RA. Citrullinated forms of thrombospondin-1, β-actin, and platelet factor-4 (also known as CXCL4) are highly immunogenic and bound by autoantibodies ACPA. Furthermore, ACPA from RA sera and synovial fluids recognized citrullinated proteins from platelets and significantly activated them as evidenced by P-selectin upregulation and sCD40 L secretion. These results clearly demonstrate the presence of citrullinated autoantigens in platelets and PDPs, thus could serve as potential targets of ACPA in RA.
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Affiliation(s)
- Minjie Xu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Rong Du
- Department of Rheumatology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wenping Xing
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Xueting Chen
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Jian Wan
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Shengqing Wang
- Department of Dermatology, Hospital affiliated to Central China Normal University, Wuhan, China
| | - Li Xiong
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Kutty Selva Nandakumar
- Department of Environmental and Biosciences, School of Business, Innovation and Sustainability, Halmstad University, Halmstad, Sweden
| | - Rikard Holmdahl
- Division of Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Hui Geng
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
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3
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Zhu C, Liu C, Chai Z. Role of the PADI family in inflammatory autoimmune diseases and cancers: A systematic review. Front Immunol 2023; 14:1115794. [PMID: 37020554 PMCID: PMC10067674 DOI: 10.3389/fimmu.2023.1115794] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 02/08/2023] [Indexed: 04/07/2023] Open
Abstract
The peptidyl arginine deiminase (PADI) family is a calcium ion-dependent group of isozymes with sequence similarity that catalyze the citrullination of proteins. Histones can serve as the target substrate of PADI family isozymes, and therefore, the PADI family is involved in NETosis and the secretion of inflammatory cytokines. Thus, the PADI family is associated with the development of inflammatory autoimmune diseases and cancer, reproductive development, and other related diseases. In this review, we systematically discuss the role of the PADI family in the pathogenesis of various diseases based on studies from the past decade to provide a reference for future research.
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Affiliation(s)
- Changhui Zhu
- Department of Plastic Surgery, Shandong Provincial Qianfoshan Hospital, School of Basic Medical Sciences, Weifang Medical University, Weifang, Shandong, China
- Shandong Provincial Key Laboratory for Rheumatic Disease and Translational Medicine, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Chunyan Liu
- Shandong Provincial Key Laboratory for Rheumatic Disease and Translational Medicine, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Jinan, China
- *Correspondence: Chunyan Liu, ; Zhengbin Chai,
| | - Zhengbin Chai
- Department of Clinical Laboratory Medicine, Shandong Public Health Clinical Center, Shandong University, Jinan, China
- *Correspondence: Chunyan Liu, ; Zhengbin Chai,
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4
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Citrullination: A modification important in the pathogenesis of autoimmune diseases. Clin Immunol 2022; 245:109134. [DOI: 10.1016/j.clim.2022.109134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 09/13/2022] [Accepted: 09/19/2022] [Indexed: 11/18/2022]
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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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6
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Rast JP, D'Alessio S, Kraev I, Lange S. Post-translational protein deimination signatures in sea lamprey (Petromyzon marinus) plasma and plasma-extracellular vesicles. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 125:104225. [PMID: 34358577 DOI: 10.1016/j.dci.2021.104225] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/30/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
Lampreys are a jawless vertebrate species belonging to an ancient vertebrate lineage that diverged from a common ancestor with humans ~500 million years ago. The sea lamprey (Petromyzon marinus) has a filter feeding ammocoete larval stage that metamorphoses into a parasitic adult, feeding both on teleost and elasmobranch fish. Lampreys are a valuable comparative model species for vertebrate immunity and physiology due to their unique phylogenetic position, unusual adaptive immune system, and physiological adaptions such as tolerance to salinity changes and urea. Peptidylarginine deiminases (PADs) are a phylogenetically conserved enzyme family which catalyses post-translational deimination/citrullination in target proteins, enabling proteins to gain new functions (moonlighting). The identification of deiminated protein targets in species across phylogeny may provide novel insights into post-translational regulation of physiological and pathophysiological processes. Extracellular vesicles (EVs) are membrane vesicles released from cells that carry cargos of small molecules and proteins for cellular communication, involved in both normal and pathological processes. The current study identified deimination signatures in proteins of both total plasma and plasma-EVs in sea lamprey and furthermore reports the first characterisation of plasma-EVs in lamprey. EVs were poly-dispersed in the size range of 40-500 nm, similar to what is observed in other taxa, positive for CD63 and Flotillin-1. Plasma-EV morphology was confirmed by transmission electron microscopy. Assessment of deimination/citrullination signatures in lamprey plasma and plasma-EVs, revealed 72 deimination target proteins involved in immunity, metabolism and gene regulation in whole plasma, and 37 target proteins in EVs, whereof 24 were shared targets. Furthermore, the presence of deiminated histone H3, indicative of gene-regulatory mechanisms and also a marker of neutrophil extracellular trap formation (NETosis), was confirmed in lamprey plasma. Functional protein network analysis revealed some differences in KEGG and GO pathways of deiminated proteins in whole plasma compared with plasma-EVs. For example, while common STRING network clusters in plasma and plasma-EVs included Peptide chain elongation, Viral mRNA translation, Glycolysis and gluconeogenesis, STRING network clusters specific for EVs only included: Cellular response to heat stress, Muscle protein and striated muscle thin filament, Nucleosome, Protein processing in endoplasmic reticulum, Nucleosome and histone deacetylase complex. STRING network clusters specific for plasma were: Adipokinetic hormone receptor activity, Fibrinogen alpha/beta chain family, peptidase S1A, Glutathione synthesis and recycling-arginine, Fructose 1,6-bisphosphate metabolic process, Carbon metabolism and lactate dehydrogenase activity, Post-translational protein phosphorylation, Regulation of insulin-like growth factor transport and clotting cascade. Overall, for the EV citrullinome, five STRING network clusters, 10 KEGG pathways, 15 molecular GO pathways and 29 Reactome pathways were identified, compared with nine STRING network clusters, six KEGG pathways, two Molecular GO pathways and one Reactome pathway specific for whole plasma; while further pathways were shared. The reported findings indicate that major pathways relevant for immunity and metabolism are targets of deimination in lamprey plasma and plasma-EVs, with some differences, and may help elucidating roles for the conserved PAD enzyme family in regulation of immune and metabolic function throughout phylogeny.
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Affiliation(s)
- Jonathan P Rast
- Emory University School of Medicine, Pathology & Laboratory Medicine, Atlanta, GA, 30322, USA.
| | - Stefania D'Alessio
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London, W1W 6UW, UK
| | - Igor Kraev
- Electron Microscopy Suite, Faculty of Science, Technology, Engineering and Mathematics, Open University, Milton Keynes, MK7 6AA, UK.
| | - Sigrun Lange
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London, W1W 6UW, UK.
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7
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Martín Monreal MT, Rebak AS, Massarenti L, Mondal S, Šenolt L, Ødum N, Nielsen ML, Thompson PR, Nielsen CH, Damgaard D. Applicability of Small-Molecule Inhibitors in the Study of Peptidyl Arginine Deiminase 2 (PAD2) and PAD4. Front Immunol 2021; 12:716250. [PMID: 34737738 PMCID: PMC8560728 DOI: 10.3389/fimmu.2021.716250] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 09/20/2021] [Indexed: 11/13/2022] Open
Abstract
Citrullination, the conversion of peptidyl-arginine into peptidyl-citrulline, is involved in the breakage of self-tolerance in anti-CCP-positive rheumatoid arthritis. This reaction is catalyzed by peptidyl arginine deiminases (PADs), of which PAD2 and PAD4 are thought to play key pathogenic roles. Small-molecule PAD inhibitors such as the pan-PAD inhibitor BB-Cl-amidine, the PAD2-specific inhibitor AFM-30a, and the PAD4-specific inhibitor GSK199 hold therapeutic potential and are useful tools in studies of citrullination. Using an ELISA based on the citrullination of fibrinogen, we found that AFM-30a inhibited the catalytic activity of PADs derived from live PMNs or lysed PBMCs and PMNs and of PADs in cell-free synovial fluid samples from RA patients, while GSK199 had minor effects. In combination, AFM-30a and GSK199 inhibited total intracellular citrullination and citrullination of histone H3 in PBMCs, as determined by Western blotting. They were essentially nontoxic to CD4+ T cells, CD8+ T cells, B cells, NK cells, and monocytes at concentrations ranging from 1 to 20 μM, while BB-Cl-amidine was cytotoxic at concentrations above 1 μM, as assessed by flow cytometric viability staining and by measurement of lactate dehydrogenase released from dying cells. In conclusion, AFM-30a is an efficient inhibitor of PAD2 derived from PBMCs, PMNs, or synovial fluid. AFM-30a and GSK199 can be used in combination for inhibition of PAD activity associated with PBMCs but without the cytotoxic effect of BB-Cl-amidine. This suggests that AFM-30a and GSK199 may have fewer off-target effects than BB-Cl-amidine and therefore hold greater therapeutic potential.
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Affiliation(s)
- María Teresa Martín Monreal
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Alexandra Stripp Rebak
- Department of Proteomics, Novo Nordisk Foundation Center for Protein Research (NNF CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Laura Massarenti
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Santanu Mondal
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, Worcester, MA, United States
| | - Ladislav Šenolt
- Institute of Rheumatology and Department of Rheumatology, 1st Faculty of Medicine, Charles University, Prague, Czechia
| | - Niels Ødum
- LEO Foundation Skin Immunology Research Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Michael L Nielsen
- Department of Proteomics, Novo Nordisk Foundation Center for Protein Research (NNF CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Paul R Thompson
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, Worcester, MA, United States
| | - Claus H Nielsen
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Section for Periodontology, Department of Odontology, 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
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8
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Massarenti L, Enevold C, Damgaard D, Ødum N, Garred P, Frisch M, Shelef MA, Jacobsen S, Nielsen CH. PADI4 Polymorphisms Confer Risk of Anti-CCP-Positive Rheumatoid Arthritis in Synergy With HLA-DRB1*04 and Smoking. Front Immunol 2021; 12:707690. [PMID: 34733271 PMCID: PMC8558474 DOI: 10.3389/fimmu.2021.707690] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 09/14/2021] [Indexed: 01/31/2023] Open
Abstract
Peptidylarginine deiminases (PADs) catalyze citrullination, a post-translational modification playing a pathogenic role in anti-citrullinated protein antibody (ACPA)-positive rheumatoid arthritis (RA). The interplay between single nucleotide polymorphisms (SNPs) in the PADI genes and known risk factors for ACPA-positive RA, including smoking, HLA-DR4 and -1, and the PTPN22 R620W polymorphism, was investigated. We typed four PADI2 SNPs, four PADI4 SNPs, and the PTPN22 R620W SNP in 445 Danish RA patients and 533 age-matched healthy controls, as well as in 200 North American RA patients and 100 age- and sex-matched controls. The HLA-DRB1 locus was typed in the Danish cohort. Logistic regression analyses, adjusted for age, sex, smoking status, and PTPN22 R620W, revealed increased risk of anti-CCP-positive RA in carriers of rs11203367(T) (OR: 1.22, p=0.03) and reduced risk in carriers of rs2240335(A) in PADI4 (OR: 0.82, p=0.04). rs74058715(T) in PADI4 conferred reduced risk of anti-CCP-negative RA (OR: 0.38, p=0.003). In HLA-DRB1*04-positive individuals, specifically, the risk of anti-CCP-positive RA was increased by carriage of PADI4 rs1748033(T) (OR: 1.54, p=0.007) and decreased by carriage of PADI4 rs74058715(T) (OR: 0.44, p=0.01), and we observed an interaction between these SNPs and HLA-DRB1*04 (p=0.004 and p=0.008, respectively) Thus, PADI4 polymorphisms associate with ACPA-positive RA, particularly in HLA-DRB1*04-positive individuals, and with ACPA-negative RA independently of HLA-DRB1*04.
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Affiliation(s)
- Laura Massarenti
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Section 7521, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Christian Enevold
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Section 7521, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Dres Damgaard
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Section 7521, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Niels Ødum
- LEO Foundation Skin Immunology Research Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Peter Garred
- Laboratory of Molecular Medicine, Department of Clinical Immunology, Section 7631, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Morten Frisch
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
| | - Miriam A Shelef
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States.,William S. Middleton Memorial Veterans Hospital, Madison, WI, United States
| | - Søren Jacobsen
- Copenhagen Lupus and Vasculitis Clinic, Center for Rheumatology and Spine Diseases, Section 4242, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Claus Henrik Nielsen
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Section 7521, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.,Department of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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9
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Poulsen TBG, Damgaard D, Jørgensen MM, Senolt L, Blackburn JM, Nielsen CH, Stensballe A. Identification of potential autoantigens in anti-CCP-positive and anti-CCP-negative rheumatoid arthritis using citrulline-specific protein arrays. Sci Rep 2021; 11:17300. [PMID: 34453079 PMCID: PMC8397748 DOI: 10.1038/s41598-021-96675-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 08/09/2021] [Indexed: 11/17/2022] Open
Abstract
The presence or absence of autoantibodies against citrullinated proteins (ACPAs) distinguishes two main groups of rheumatoid arthritis (RA) patients with different etiologies, prognoses, disease severities, and, presumably, disease pathogenesis. The heterogeneous responses of RA patients to various biologics, even among ACPA-positive patients, emphasize the need for further stratification of the patients. We used high-density protein array technology for fingerprinting of ACPA reactivity. Identification of the proteome recognized by ACPAs may be a step to stratify RA patients according to immune reactivity. Pooled plasma samples from 10 anti-CCP-negative and 15 anti-CCP-positive RA patients were assessed for ACPA content using a modified protein microarray containing 1631 different natively folded proteins citrullinated in situ by protein arginine deiminases (PADs) 2 and PAD4. IgG antibodies from anti-CCP-positive RA plasma showed high-intensity binding to 87 proteins citrullinated by PAD2 and 99 proteins citrullinated by PAD4 without binding significantly to the corresponding native proteins. Curiously, the binding of IgG antibodies in anti-CCP-negative plasma was also enhanced by PAD2- and PAD4-mediated citrullination of 29 and 26 proteins, respectively. For only four proteins, significantly more ACPA binding occurred after citrullination with PAD2 compared to citrullination with PAD4, while the opposite was true for one protein. We demonstrate that PAD2 and PAD4 are equally efficient in generating citrullinated autoantigens recognized by ACPAs. Patterns of proteins recognized by ACPAs may serve as a future diagnostic tool for further subtyping of RA patients.
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Affiliation(s)
- Thomas B G Poulsen
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 5, 9220, Aalborg, Denmark.,Sino-Danish College (SDC), University of Chinese Academy of Sciences, Beijing, China
| | - Dres Damgaard
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Malene M Jørgensen
- Department of Clinical Immunology, Aalborg University Hospital, Aalborg, Denmark.,Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | - Ladislav Senolt
- Institute of Rheumatology and Department of Rheumatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Jonathan M Blackburn
- Department of Integrative Biomedical Sciences and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Claus H Nielsen
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Allan Stensballe
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 5, 9220, Aalborg, Denmark.
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10
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Discovery of new inhibitor for the protein arginine deiminase type 4 (PAD4) by rational design of α-enolase-derived peptides. Comput Biol Chem 2021; 92:107487. [PMID: 33957477 DOI: 10.1016/j.compbiolchem.2021.107487] [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] [Received: 02/28/2021] [Accepted: 04/21/2021] [Indexed: 12/13/2022]
Abstract
Rheumatoid arthritis (RA) is an inflammatory autoimmune disease affecting about 0.24 % of the world population. Protein arginine deiminase type 4 (PAD4) is believed to be responsible for the occurrence of RA by catalyzing citrullination of proteins. The citrullinated proteins act as autoantigens by stimulating an immune response. Citrullinated α-enolase has been identified as one of the autoantigens for RA. Hence, α-enolase serves as a suitable template for design of potential peptide inhibitors against PAD4. The binding affinity of α-enolase-derived peptides and PAD4 was virtually determined using PatchDock and HADDOCK docking programs. Synthesis of the designed peptides was performed using a solid phase peptide synthesis method. The inhibitory potential of each peptide was determined experimentally by PAD4 inhibition assay and IC50 measurement. PAD4 assay data show that the N-P2 peptide is the most favourable substrate among all peptides. Further modification of N-P2 by changing the Arg residue to canavanine [P2 (Cav)] rendered it an inhibitor against PAD4 by reducing the PAD4 activity to 35 % with IC50 1.39 mM. We conclude that P2 (Cav) is a potential inhibitor against PAD4 and can serve as a starting point for the development of even more potent inhibitors.
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11
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Julià A, López-Lasanta M, Blanco F, Gómez A, Haro I, Mas AJ, Erra A, Vivar MLG, Monfort J, Sánchez-Fernández S, González I, Alperi M, Castellanos-Moreira R, Fernández-Nebro A, Díaz-Torné C, Palau N, Lastra R, Lladós J, Sanmartí R, Marsal S. Interactions between rheumatoid arthritis antibodies are associated with the response to anti-tumor necrosis factor therapy. BMC Musculoskelet Disord 2021; 22:372. [PMID: 33882889 PMCID: PMC8061050 DOI: 10.1186/s12891-021-04248-y] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 04/12/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Blocking of the Tumor Necrosis Factor (TNF) activity is a successful therapeutic approach for 50-60% of rheumatoid arthritis (RA) patients. However, there are yet no biomarkers to stratify patients for anti-TNF therapy. Rheumatoid factor (RF) and anti-cyclic-citrullinated antibodies (anti-CCP) have been evaluated as biomarkers of response but the results have shown limited consistency. Anti-carbamylated protein (anti-CarP) and anti-peptidylarginine deiminase type 4 (anti-PAD4) antibodies have been much less studied. Despite being linked to common immune processes, the interaction between these markers has not been evaluated yet. Our aim was to analyze the interaction between these four antibodies in relation to the response to anti-TNF therapy. METHODS For this objective, a prospective cohort of n = 80 RA patients starting anti-TNF therapy was recruited. Serum determinations at baseline were performed for RF, anti-CCP, anti-CarP and anti-PAD4 antibodies using enzyme-linked immunosorbent assays (ELISA). The clinical response to anti-TNF therapy was determined at week 12 using the change in DAS28 score. Association was performed using multivariate linear regression adjusting for baseline DAS28, sex and age. RESULTS The interaction between pairs of antibodies was tested by the addition of an interaction term. We found two highly significant antibody interactions associated with treatment response: anti-CarP with anti-PAD4 (p = 0.0062), and anti-CCP with RF (p = 0.00068). The latter antibody interaction was replicated in an independent retrospective cohort of RA patients (n = 199, p = 0.04). CONCLUSIONS The results of this study suggest that antibody interaction effects are important factors in the response to anti-TNF therapy in RA.
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Affiliation(s)
- Antonio Julià
- Rheumatology Research Group, Vall d'Hebron University Hospital Research Institute, 08035, Barcelona, Spain.
| | - María López-Lasanta
- Rheumatology Research Group, Vall d'Hebron University Hospital Research Institute, 08035, Barcelona, Spain
| | - Francisco Blanco
- Rheumatology Department, INIBIC-Hospital Universitario A Coruña, A Coruña, Spain
| | - Antonio Gómez
- Rheumatology Research Group, Vall d'Hebron University Hospital Research Institute, 08035, Barcelona, Spain
| | - Isabel Haro
- Unitat de Síntesi i Aplicacions Biomèdiques de Pèptids, IQAC-CSIC, Barcelona, Spain
| | - Antonio Juan Mas
- Rheumatology Department, Hospital Universitario Son Llàtzer, Mallorca, Spain
| | - Alba Erra
- Rheumatology Research Group, Vall d'Hebron University Hospital Research Institute, 08035, Barcelona, Spain
| | | | - Jordi Monfort
- Rheumatology Department, Hospital del Mar, Barcelona, Spain
| | | | - Isidoro González
- Rheumatology Department, Hospital Universitario La Princesa, Madrid, Spain
| | - Mercedes Alperi
- Rheumatology Department, Hospital Universitario Central de Asturias, Oviedo, Spain
| | | | | | - César Díaz-Torné
- Rheumatology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Núria Palau
- Rheumatology Research Group, Vall d'Hebron University Hospital Research Institute, 08035, Barcelona, Spain
| | - Raquel Lastra
- Rheumatology Research Group, Vall d'Hebron University Hospital Research Institute, 08035, Barcelona, Spain
| | - Jordi Lladós
- Rheumatology Research Group, Vall d'Hebron University Hospital Research Institute, 08035, Barcelona, Spain
| | - Raimon Sanmartí
- Rheumatology Department, Fundació Clínic Recerca Biomèdica, Barcelona, Spain
| | - Sara Marsal
- Rheumatology Research Group, Vall d'Hebron University Hospital Research Institute, 08035, Barcelona, Spain
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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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13
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Song W, Ye J, Pan N, Tan C, Herrmann M. Neutrophil Extracellular Traps Tied to Rheumatoid Arthritis: Points to Ponder. Front Immunol 2021; 11:578129. [PMID: 33584645 PMCID: PMC7878527 DOI: 10.3389/fimmu.2020.578129] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 12/14/2020] [Indexed: 02/05/2023] Open
Abstract
In recent years, neutrophil extracellular traps at the forefront of neutrophil biology have proven to help capture and kill pathogens involved in the inflammatory process. There is growing evidence that persistent neutrophil extracellular traps drive the pathogenesis of autoimmune diseases. In this paper, we summarize the potential of neutrophil extracellular traps to drive the pathogenesis of rheumatoid arthritis and experimental animal models. We also describe the diagnosis and treatment of rheumatoid arthritis in association with neutrophil extracellular traps.
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Affiliation(s)
- Wenpeng Song
- Department of Rheumatology, West China Hospital of Sichuan University, Chengdu, China
| | - Jing Ye
- Department of Rheumatology, West China Hospital of Sichuan University, Chengdu, China
| | - Nanfang Pan
- Department of Rheumatology, West China Hospital of Sichuan University, Chengdu, China
| | - Chunyu Tan
- Department of Rheumatology, West China Hospital of Sichuan University, Chengdu, China
| | - Martin Herrmann
- Department of Internal Medicine 3, Universitätsklinik Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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14
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Bezuidenhout JA, Venter C, Roberts TJ, Tarr G, Kell DB, Pretorius E. Detection of Citrullinated Fibrin in Plasma Clots of Rheumatoid Arthritis Patients and Its Relation to Altered Structural Clot Properties, Disease-Related Inflammation and Prothrombotic Tendency. Front Immunol 2020; 11:577523. [PMID: 33424834 PMCID: PMC7793985 DOI: 10.3389/fimmu.2020.577523] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 11/05/2020] [Indexed: 01/19/2023] Open
Abstract
Aims The risk of cardiovascular events in patients with Rheumatoid Arthritis (RA) is disproportionately heightened as a result of systemic inflammation. The relative effect of autoimmune-associated citrullination on the structure and thrombotic potential of fibrin(ogen) remains unknown. We therefore compared indices of vascular function, inflammation, coagulation and fibrin clot composition in RA patients with healthy controls and evaluated parameter association with disease presence. Methods Blood samples were collected from 30 RA patients and 30 age- and gender-matched healthy volunteers. Levels of serum amyloid A (SAA), c-reactive protein (CRP), soluble intercellular adhesion molecule 1 (sICAM-1) and soluble vascular cell adhesion molecule 1 (sVCAM-1) was measured using a sandwich immunoassay. Whole blood coagulation was assessed using Thromboelastography (TEG®). Fibrin clot networks and fiber structure was investigated using Scanning Electron Microscopy. The detection and quantification of citrullination in formed fibrin clots was performed using a fluorescently labeled Citrulline monoclonal antibody with Fluorescence Wide Field Microscopy. Results Concentrations of SAA, CRP and ICAM-1 were significantly elevated in RA patients compared to controls. TEG parameters relating to coagulation initiation, rate of fibrin cross-linking, and time to reach maximum thrombus generation were attenuated in RA patients. Microscopic analysis revealed denser networks of thicker fibrin fibers in RA patients compared to controls and multiple citrullinated regions within fibrin clot structures in RA patients were present. Conclusion Our findings provide novel evidence for the citrullination of fibrin within vasculature is more prominent in RA plasma compared to control plasma and plasma is more accessible than synovial fluid. Citrullinated fibrinogen could play a role as a determinant of thrombotic risk in RA patients.
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Affiliation(s)
- Johannes A Bezuidenhout
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| | - Chantelle Venter
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| | - Timothy J Roberts
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa.,Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom.,Department of Clinical Epidemiology, University College London Hospital NHS Foundation Trust, London, United Kingdom
| | - Gareth Tarr
- Division of Rheumatology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Douglas B Kell
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa.,Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom.,The Novo Nordisk Foundation Centre for Biosustainability, Kemitorvet, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Etheresia Pretorius
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
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15
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Bowden TJ, Kraev I, Lange S. Extracellular Vesicles and Post-Translational Protein Deimination Signatures in Mollusca-The Blue Mussel ( Mytilus edulis), Soft Shell Clam ( Mya arenaria), Eastern Oyster ( Crassostrea virginica) and Atlantic Jacknife Clam ( Ensis leei). BIOLOGY 2020; 9:biology9120416. [PMID: 33255637 PMCID: PMC7760292 DOI: 10.3390/biology9120416] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 12/20/2022]
Abstract
Simple Summary Oysters and clams form an important component of the food chain and food security and are of considerable commercial value worldwide. They are affected by pollution and climate change, as well as a range of infections, some of which are opportunistic. For aquaculture purposes they are furthermore of great commercial value and changes in their immune responses can also serve as indicators of changes in ocean environments. Therefore, studies into understanding new factors in their immune systems may aid new biomarker discovery and are of considerable value. This study assessed new biomarkers relating to changes in protein function in four economically important marine molluscs, the blue mussel, soft shell clam, Eastern oyster, and Atlantic jacknife clam. These findings indicate novel regulatory mechanisms of important metabolic and immunology related pathways in these mollusks. The findings provide new understanding to how these pathways function in diverse ways in different animal species as well as aiding new biomarker discovery for Mollusca aquaculture. Abstract Oysters and clams are important for food security and of commercial value worldwide. They are affected by anthropogenic changes and opportunistic pathogens and can be indicators of changes in ocean environments. Therefore, studies into biomarker discovery are of considerable value. This study aimed at assessing extracellular vesicle (EV) signatures and post-translational protein deimination profiles of hemolymph from four commercially valuable Mollusca species, the blue mussel (Mytilus edulis), soft shell clam (Mya arenaria), Eastern oyster (Crassostrea virginica), and Atlantic jacknife clam (Ensis leei). EVs form part of cellular communication by transporting protein and genetic cargo and play roles in immunity and host–pathogen interactions. Protein deimination is a post-translational modification caused by peptidylarginine deiminases (PADs), and can facilitate protein moonlighting in health and disease. The current study identified hemolymph-EV profiles in the four Mollusca species, revealing some species differences. Deiminated protein candidates differed in hemolymph between the species, with some common targets between all four species (e.g., histone H3 and H4, actin, and GAPDH), while other hits were species-specific; in blue mussel these included heavy metal binding protein, heat shock proteins 60 and 90, 2-phospho-D-glycerate hydrolyase, GTP cyclohydrolase feedback regulatory protein, sodium/potassium-transporting ATPase, and fibrinogen domain containing protein. In soft shell clam specific deimination hits included dynein, MCM3-associated protein, and SCRN. In Eastern oyster specific deimination hits included muscle LIM protein, beta-1,3-glucan-binding protein, myosin heavy chain, thaumatin-like protein, vWFA domain-containing protein, BTB domain-containing protein, amylase, and beta-catenin. Deiminated proteins specific to Atlantic jackknife clam included nacre c1q domain-containing protein and PDZ domain-containing protein In addition, some proteins were common as deiminated targets between two or three of the Bivalvia species under study (e.g., EP protein, C1q domain containing protein, histone H2B, tubulin, elongation factor 1-alpha, dominin, extracellular superoxide dismutase). Protein interaction network analysis for the deiminated protein hits revealed major pathways relevant for immunity and metabolism, providing novel insights into post-translational regulation via deimination. The study contributes to EV characterization in diverse taxa and understanding of roles for PAD-mediated regulation of immune and metabolic pathways throughout phylogeny.
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Affiliation(s)
- Timothy J. Bowden
- Aquaculture Research Institute, School of Food & Agriculture, University of Maine, Orono, ME 04469-5735, USA;
| | - Igor Kraev
- Electron Microscopy Suite, Faculty of Science, Technology, Engineering and Mathematics, Open University, Milton Keynes MK7 6AA, UK;
| | - Sigrun Lange
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London W1W 6UW, UK
- Correspondence: ; Tel.: +44-(0)207-911-5000
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16
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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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Curran AM, Naik P, Giles JT, Darrah E. PAD enzymes in rheumatoid arthritis: pathogenic effectors and autoimmune targets. Nat Rev Rheumatol 2020; 16:301-315. [PMID: 32341463 DOI: 10.1038/s41584-020-0409-1] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2020] [Indexed: 12/11/2022]
Abstract
Peptidylarginine deiminases (PADs) have an important role in the pathogenesis of rheumatoid arthritis (RA) owing to their ability to generate citrullinated proteins - the hallmark autoantigens of RA. Of the five PAD enzyme isoforms, PAD2 and PAD4 are the most strongly implicated in RA at both genetic and cellular levels, and PAD inhibitors have shown therapeutic efficacy in mouse models of inflammatory arthritis. PAD2 and PAD4 are additionally targeted by autoantibodies in distinct clinical subsets of patients with RA, suggesting anti-PAD antibodies as possible biomarkers for RA diagnosis and prognosis. This Review weighs the evidence that supports a pathogenic role for PAD enzymes in RA as both promoters and targets of the autoimmune response, as well as discussing the mechanistic and therapeutic implications of these findings in the wider context of RA pathogenesis. Understanding the origin and consequences of dysregulated PAD enzyme activity and immune responses against PAD enzymes will be important to fully comprehend the pathogenic mechanisms involved in this disease and for the development of novel strategies to treat and prevent RA.
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Affiliation(s)
- Ashley M Curran
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Pooja Naik
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jon T Giles
- Division of Rheumatology, Columbia University Vagelos College of Physicians & Surgeons, New York, NY, USA
| | - Erika Darrah
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Romero V, Darrah E, Andrade F. Generation of Distinct Patterns of Rheumatoid Arthritis Autoantigens by Peptidylarginine Deiminase Types 2 and 4 During Perforin-Induced Cell Damage. Arthritis Rheumatol 2020; 72:912-918. [PMID: 31876120 DOI: 10.1002/art.41196] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 12/19/2019] [Indexed: 12/14/2022]
Abstract
OBJECTIVE To address the independent roles of peptidylarginine deiminase type 2 (PAD2) and PAD4 in generating rheumatoid arthritis (RA) autoantigens by using a system that mimics intracellular citrullination in the RA joint. METHODS PAD2- or PAD4-expressing 293T cells and mock-transfected cells were used as targets in cytotoxic assays using lymphokine-activated killer cells, cytotoxic YT cell granule contents, or purified human perforin. Protein citrullination and autoantigen production were determined by immunoblotting using the anti-modified citrulline-Senshu method and RA sera (n = 30), respectively. RESULTS RA sera recognized at least 3 categories of autoantigens in PAD-expressing target cells killed by the cytotoxic lymphocyte granule-induced death pathway. These included: 1) autoantigens targeted in their native form, 2) citrullinated antigens, and 3) antigens cleaved by cytotoxic proteases (e.g., granzymes). Interestingly, although target cells expressing PAD2 or PAD4 showed prominent hypercitrullination of a broad range of proteins during cytotoxic granule-induced cell damage, autoantibodies in RA sera targeted only a very limited number of antigens in hypercitrullinated cells. Furthermore, RA sera showed distinct reactivities to autoantigens generated by PAD2 or PAD4. CONCLUSION The cytotoxic granule-induced death pathway has the capacity to modify antigens by inducing hypercitrullination and antigen cleavage in target cells. Interestingly, among a large number of citrullinated proteins generated by PAD2 and PAD4 in cells, only a few are likely involved in the production of autoantibodies in RA.
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Affiliation(s)
- Violeta Romero
- The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Erika Darrah
- The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Felipe Andrade
- The Johns Hopkins University School of Medicine, Baltimore, Maryland
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Li J, Zhi X, Chen S, Shen X, Chen C, Yuan L, Guo J, Meng D, Chen M, Yao L. CDK9 inhibitor CDKI-73 is synergetic lethal with PARP inhibitor olaparib in BRCA1 wide-type ovarian cancer. Am J Cancer Res 2020; 10:1140-1155. [PMID: 32368391 PMCID: PMC7191097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 03/09/2020] [Indexed: 06/11/2023] Open
Abstract
Poly (adenosine diphosphate ribose) polymerase (PARP) inhibitors benefit a small percentage of ovarian cancer patients with homologous recombination (HR) deficiency (HRD), which greatly limits the applications of PARP inhibitors. Given the function of CDK9 in homologous recombination repair (HRR), here, we show how to extend the utility of PARP inhibitors in BRCA1-proficient ovarian cancer by targeting CDK9. We found that high CDK9 expression is associated with a higher tumor stage in epithelial ovarian cancer patients, and CDK9 is co-expressed with BRCA1 by analyzing a public database. By using a CDK9 inhibitor CDKI-73, we found that its combination with the PARP inhibitor olaparib significantly suppressed cell viability and colony formation and induced apoptosis in BRCA1-proficient ovarian cancer cells. Consistently, the combination treatment remarkably reduced the tumor growth in mouse xenograft models. We demonstrated that CDKI-73 could downregulate BRCA1 expression, resulting in hypersensitivity to olaparib in BRCA1-proficient ovarian cancer. Taken together, our results show a synergetic effect of CDKI-73 combined with olaparib in BRCA1-proficient ovarian cancer, facilitating the clinical use of CDK9 as a predictive biomarker to exploit PARP inhibitors.
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Affiliation(s)
- Jiajia Li
- Department of Gynecology, Obstetrics & Gynecology Hospital, Fudan UniversityShanghai 200011, China
| | - Xiuling Zhi
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan UniversityShanghai 200032, China
| | - Shuyi Chen
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan UniversityShanghai 200032, China
| | - Xiaoqing Shen
- Department of Gynecology, Obstetrics & Gynecology Hospital, Fudan UniversityShanghai 200011, China
| | - Chen Chen
- Department of Gynecology, Obstetrics & Gynecology Hospital, Fudan UniversityShanghai 200011, China
| | - Lei Yuan
- Department of Gynecology, Obstetrics & Gynecology Hospital, Fudan UniversityShanghai 200011, China
| | - Jieyu Guo
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan UniversityShanghai 200032, China
| | - Dan Meng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan UniversityShanghai 200032, China
| | - Mo Chen
- Department of Gynecology, Obstetrics & Gynecology Hospital, Fudan UniversityShanghai 200011, China
| | - Liangqing Yao
- Department of Gynecology, Obstetrics & Gynecology Hospital, Fudan UniversityShanghai 200011, China
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Magnadóttir B, Uysal-Onganer P, Kraev I, Svansson V, Hayes P, Lange S. Deiminated proteins and extracellular vesicles - Novel serum biomarkers in whales and orca. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2020; 34:100676. [PMID: 32114311 DOI: 10.1016/j.cbd.2020.100676] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 01/16/2020] [Accepted: 02/17/2020] [Indexed: 02/06/2023]
Abstract
Peptidylarginine deiminases (PADs) are a family of phylogenetically conserved calcium-dependent enzymes which cause post-translational protein deimination. This can result in neoepitope generation, affect gene regulation and allow for protein moonlighting via functional and structural changes in target proteins. Extracellular vesicles (EVs) carry cargo proteins and genetic material and are released from cells as part of cellular communication. EVs are found in most body fluids where they can be useful biomarkers for assessment of health status. Here, serum-derived EVs were profiled, and post-translationally deiminated proteins and EV-related microRNAs are described in 5 ceataceans: minke whale, fin whale, humpback whale, Cuvier's beaked whale and orca. EV-serum profiles were assessed by transmission electron microscopy and nanoparticle tracking analysis. EV profiles varied between the 5 species and were identified to contain deiminated proteins and selected key inflammatory and metabolic microRNAs. A range of proteins, critical for immune responses and metabolism were identified to be deiminated in cetacean sera, with some shared KEGG pathways of deiminated proteins relating to immunity and physiology, while some KEGG pathways were species-specific. This is the first study to characterise and profile EVs and to report deiminated proteins and putative effects of protein-protein interaction networks via such post-translationald deimination in cetaceans, revealing key immune and metabolic factors to undergo this post-translational modification. Deiminated proteins and EVs profiles may possibly be developed as new biomarkers for assessing health status of sea mammals.
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Affiliation(s)
- Bergljót Magnadóttir
- Institute for Experimental Pathology, University of Iceland, Keldur v. Vesturlandsveg, 112 Reykjavik, Iceland.
| | - Pinar Uysal-Onganer
- Cancer Research Group, School of Life Sciences, University of Westminster, London W1W 6UW, UK.
| | - Igor Kraev
- Electron Microscopy Suite, Faculty of Science, Technology, Engineering and Mathematics, Open University, Milton Keynes MK7 6AA, UK.
| | - Vilhjálmur Svansson
- Institute for Experimental Pathology, University of Iceland, Keldur v. Vesturlandsveg, 112 Reykjavik, Iceland
| | - Polly Hayes
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London W1W 6UW, UK.
| | - Sigrun Lange
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London W1W 6UW, UK.
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21
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Phillips RA, Kraev I, Lange S. Protein Deimination and Extracellular Vesicle Profiles in Antarctic Seabirds. BIOLOGY 2020; 9:E15. [PMID: 31936359 PMCID: PMC7168935 DOI: 10.3390/biology9010015] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 12/19/2019] [Accepted: 01/07/2020] [Indexed: 02/06/2023]
Abstract
Pelagic seabirds are amongst the most threatened of all avian groups. They face a range of immunological challenges which seem destined to increase due to environmental changes in their breeding and foraging habitats, affecting prey resources and exposure to pollution and pathogens. Therefore, the identification of biomarkers for the assessment of their health status is of considerable importance. Peptidylarginine deiminases (PADs) post-translationally convert arginine into citrulline in target proteins in an irreversible manner. PAD-mediated deimination can cause structural and functional changes in target proteins, allowing for protein moonlighting in physiological and pathophysiological processes. PADs furthermore contribute to the release of extracellular vesicles (EVs), which play important roles in cellular communication. In the present study, post-translationally deiminated protein and EV profiles of plasma were assessed in eight seabird species from the Antarctic, representing two avian orders: Procellariiformes (albatrosses and petrels) and Charadriiformes (waders, auks, gulls and skuas). We report some differences between the species assessed, with the narrowest EV profiles of 50-200 nm in the northern giant petrel Macronectes halli, and the highest abundance of larger 250-500 nm EVs in the brown skua Stercorarius antarcticus. The seabird EVs were positive for phylogenetically conserved EV markers and showed characteristic EV morphology. Post-translational deimination was identified in a range of key plasma proteins critical for immune response and metabolic pathways in three of the bird species under study; the wandering albatross Diomedea exulans, south polar skua Stercorarius maccormicki and northern giant petrel. Some differences in Gene Ontology (GO) biological and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways for deiminated proteins were observed between these three species. This indicates that target proteins for deimination may differ, potentially contributing to a range of physiological functions relating to metabolism and immune response, as well as to key defence mechanisms. PAD protein homologues were identified in the seabird plasma by Western blotting via cross-reaction with human PAD antibodies, at an expected 75 kDa size. This is the first study to profile EVs and to identify deiminated proteins as putative novel plasma biomarkers in Antarctic seabirds. These biomarkers may be further refined to become useful indicators of physiological and immunological status in seabirds-many of which are globally threatened.
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Affiliation(s)
- Richard A. Phillips
- British Antarctic Survey, Natural Environment Research Council, Cambridge CB3 0ET, UK;
| | - Igor Kraev
- Electron Microscopy Suite, Faculty of Science, Technology, Engineering and Mathematics, Open University, Milton Keynes MK7 6AA, UK;
| | - Sigrun Lange
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London W1W 6UW, UK
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22
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Criscitiello MF, Kraev I, Lange S. Deiminated proteins in extracellular vesicles and serum of llama (Lama glama)-Novel insights into camelid immunity. Mol Immunol 2020; 117:37-53. [PMID: 31733447 PMCID: PMC7112542 DOI: 10.1016/j.molimm.2019.10.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 10/05/2019] [Accepted: 10/23/2019] [Indexed: 02/07/2023]
Abstract
Peptidylarginine deiminases (PADs) are phylogenetically conserved calcium-dependent enzymes which post-translationally convert arginine into citrulline in target proteins in an irreversible manner, causing functional and structural changes in target proteins. Protein deimination causes generation of neo-epitopes, affects gene regulation and also allows for protein moonlighting. Furthermore, PADs have been found to be a phylogenetically conserved regulator for extracellular vesicle (EVs) release. EVs are found in most body fluids and participate in cellular communication via transfer of cargo proteins and genetic material. In this study, post-translationally deiminated proteins in serum and serum-EVs are described for the first time in camelids, using the llama (Lama glama L. 1758) as a model animal. We report a poly-dispersed population of llama serum EVs, positive for phylogenetically conserved EV-specific markers and characterised by TEM. In serum, 103 deiminated proteins were overall identified, including key immune and metabolic mediators including complement components, immunoglobulin-based nanobodies, adiponectin and heat shock proteins. In serum, 60 deiminated proteins were identified that were not in EVs, and 25 deiminated proteins were found to be unique to EVs, with 43 shared deiminated protein hits between both serum and EVs. Deiminated histone H3, a marker of neutrophil extracellular trap formation, was also detected in llama serum. PAD homologues were identified in llama serum by Western blotting, via cross reaction with human PAD antibodies, and detected at an expected 70 kDa size. This is the first report of deiminated proteins in serum and EVs of a camelid species, highlighting a hitherto unrecognized post-translational modification in key immune and metabolic proteins in camelids, which may be translatable to and inform a range of human metabolic and inflammatory pathologies.
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Affiliation(s)
- Michael F Criscitiello
- Comparative Immunogenetics Laboratory, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843, USA; Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M Health Science Center, Texas A&M University, College Station, TX, 77843, USA.
| | - Igor Kraev
- Electron Microscopy Suite, Faculty of Science, Technology, Engineering and Mathematics, Open University, Milton Keynes, MK7 6AA, UK.
| | - Sigrun Lange
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London W1W 6UW, UK.
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23
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Lo KC, Sullivan E, Bannen RM, Jin H, Rowe M, Li H, Pinapati RS, Cartwright AJ, Tan JC, Patel J, Keystone EC, Siminovitch KA. Comprehensive Profiling of the Rheumatoid Arthritis Antibody Repertoire. Arthritis Rheumatol 2019; 72:242-250. [DOI: 10.1002/art.41089] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 08/20/2019] [Indexed: 01/13/2023]
Affiliation(s)
- Ken C. Lo
- Roche Sequencing Solutions Madison Wisconsin
| | | | | | - Huiyan Jin
- Roche Sequencing Solutions Madison Wisconsin
| | - Mark Rowe
- Roche Sequencing Solutions Madison Wisconsin
| | - Hanying Li
- Roche Sequencing Solutions Madison Wisconsin
| | | | | | - John C. Tan
- Roche Sequencing Solutions Madison Wisconsin
| | - Jigar Patel
- Roche Sequencing Solutions Madison Wisconsin
| | | | - Katherine A. Siminovitch
- University of Toronto, Mount Sinai Hospital, and Toronto General Hospital Toronto Ontario Canada
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24
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Citrullination of fibrinogen by peptidylarginine deiminase 2 impairs fibrin clot structure. Clin Chim Acta 2019; 501:6-11. [PMID: 31730822 DOI: 10.1016/j.cca.2019.10.033] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 10/14/2019] [Accepted: 10/21/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND Citrullination is the post-translational conversion of arginine into citrulline in proteins. The reaction is catalyzed by peptidylarginine deiminase (PAD), of which five isoforms exist. Fibrinogen is a substrate for PAD2 and PAD4, and citrullinated fibrinogen (cFBG) has been detected in patients with inflammatory diseases. In purified systems, cFBG is known to inhibit the release of fibrinopeptide A (FPA) and B (FPB) and impairs fibrin polymerization. However, the effect of cFBG on fibrin structure and fibrinolysis in a plasma environment remains unclear. We hypothesized that citrullination of fibrinogen impairs fibrin properties. METHODS Fibrinogen was citrullinated by recombinant PAD2 and PAD4. The impact of cFBG on fibrin structure was investigated by turbidity measurements in fibrinogen-deficient plasma spiked with cFBG or native fibrinogen. RESULTS Citrullination of fibrinogen by PAD2 dose-dependently reduced the rate of fibrin polymerization, as well as the overall hemostasis potential of fibrin, the maximum velocity of fibrin formation, the fibrin mass/length ratio, and the lysis of fibrin clots. CONCLUSION Citrullination of fibrinogen by PAD2 affects not only fibrin polymerization but also fibrin fiber properties, indicating that the fibrin network formed in the presence of cFBG may influence hemostasis. Our results suggest that citrullination of fibrinogen alters the composition of fibrin fibers which may lead to a looser fibrin network that is more susceptible to fibrinolysis and thereby affecting the hemostatic balance.
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25
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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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26
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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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27
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Peptidyl-arginine deiminase-type IV as a diagnostic and prognostic marker in rheumatoid arthritis patients. EGYPTIAN RHEUMATOLOGIST 2019. [DOI: 10.1016/j.ejr.2018.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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28
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Magnadóttir B, Bragason BT, Bricknell IR, Bowden T, Nicholas AP, Hristova M, Guðmundsdóttir S, Dodds AW, Lange S. Peptidylarginine deiminase and deiminated proteins are detected throughout early halibut ontogeny - Complement components C3 and C4 are post-translationally deiminated in halibut (Hippoglossus hippoglossus L.). DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2019; 92:1-19. [PMID: 30395876 DOI: 10.1016/j.dci.2018.10.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 10/30/2018] [Accepted: 10/30/2018] [Indexed: 06/08/2023]
Abstract
Post-translational protein deimination is mediated by peptidylarginine deiminases (PADs), which are calcium dependent enzymes conserved throughout phylogeny with physiological and pathophysiological roles. Protein deimination occurs via the conversion of protein arginine into citrulline, leading to structural and functional changes in target proteins. In a continuous series of early halibut development from 37 to 1050° d, PAD, total deiminated proteins and deiminated histone H3 showed variation in temporal and spatial detection in various organs including yolksac, muscle, skin, liver, brain, eye, spinal cord, chondrocytes, heart, intestines, kidney and pancreas throughout early ontogeny. For the first time in any species, deimination of complement components C3 and C4 is shown in halibut serum, indicating a novel mechanism of complement regulation in immune responses and homeostasis. Proteomic analysis of deiminated target proteins in halibut serum further identified complement components C5, C7, C8 C9 and C1 inhibitor, as well as various other immunogenic, metabolic, cytoskeletal and nuclear proteins. Post-translational deimination may facilitate protein moonlighting, an evolutionary conserved phenomenon, allowing one polypeptide chain to carry out various functions to meet functional requirements for diverse roles in immune defences and tissue remodelling.
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Affiliation(s)
- Bergljót Magnadóttir
- Institute for Experimental Pathology, University of Iceland, Keldur v. Vesturlandsveg, 112 Reykjavik, Iceland.
| | - Birkir Thor Bragason
- Institute for Experimental Pathology, University of Iceland, Keldur v. Vesturlandsveg, 112 Reykjavik, Iceland.
| | - Ian R Bricknell
- Aquaculture Research Institute School of Marine Sciences, University of Maine, Orono, ME, USA.
| | - Timothy Bowden
- Aquaculture Research Institute School of Food & Agriculture, University of Maine, University of Maine, Orono, ME, USA.
| | - Anthony P Nicholas
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Mariya Hristova
- Perinatal Brain Protection and Repair Group, EGA Institute for Women's Health, University College London, London, WC1E 6HX, UK.
| | - Sigríður Guðmundsdóttir
- Institute for Experimental Pathology, University of Iceland, Keldur v. Vesturlandsveg, 112 Reykjavik, Iceland.
| | - Alister W Dodds
- MRC Immunochemistry Unit, Department of Biochemistry, University of Oxford, Oxford, UK.
| | - Sigrun Lange
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London, W1W 6UW, UK.
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Darrah E, Giles JT, Davis RL, Naik P, Wang H, Konig MF, Cappelli LC, Bingham CO, Danoff SK, Andrade F. Autoantibodies to Peptidylarginine Deiminase 2 Are Associated With Less Severe Disease in Rheumatoid Arthritis. Front Immunol 2018; 9:2696. [PMID: 30515171 PMCID: PMC6255931 DOI: 10.3389/fimmu.2018.02696] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/31/2018] [Indexed: 12/22/2022] Open
Abstract
Objective: Peptidylarginine deiminases (PAD) 2 and 4 are key enzymes in rheumatoid arthritis (RA) pathogenesis due to their ability to generate the protein targets of anti-citrullinated protein antibodies (ACPA). Anti-PAD4 antibodies that cross-react with PAD3 (anti-PAD3/4) have been identified and are associated with severe joint and lung disease. Here, we examined whether anti-PAD2 antibodies were present in patients with RA and defined their clinical significance. Patients and Methods: A PAD2 ELISA was established to screen for anti-PAD2 IgG in sera from RA patients from a prospective observational cohort study (n = 184) and healthy controls (n = 100). RA patient characteristics were compared according to anti-PAD2 antibody status. Multivariable models were constructed to explore the independent associations of anti-PAD2 antibodies with clinical variables. Results: Anti-PAD2 antibodies were found in 18.5% of RA patients and 3% of healthy controls (p < 0.001). Among RA patients, anti-PAD2 antibodies were not associated with traditional genetic or serologic RA risk factors, including HLA-DRβ1 shared epitope alleles, ACPA, rheumatoid factor (RF), or anti-PAD3/4 antibodies. In addition, antibodies to PAD2 were associated with fewer swollen joints, a lower prevalence of interstitial lung disease, and less progression of joint damage. In subset analyses in which patients were stratified by the baseline presence of ACPA/RF or anti-PAD3/4 antibodies, anti-PAD2 antibodies provided additional value in identifying patients with the least progressive joint disease. Conclusions: Anti-PAD2 antibodies represent a novel serologic marker in RA that identifies a genetically and clinically unique subset of patients with less severe joint and lung disease.
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Affiliation(s)
- Erika Darrah
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Jon T Giles
- Division of Rheumatology, College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Ryan L Davis
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Pooja Naik
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Hong Wang
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Maximilian F Konig
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Laura C Cappelli
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Clifton O Bingham
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Sonye K Danoff
- Division of Pulmonary and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Felipe Andrade
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
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30
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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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31
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Olsen I, Singhrao SK, Potempa J. Citrullination as a plausible link to periodontitis, rheumatoid arthritis, atherosclerosis and Alzheimer's disease. J Oral Microbiol 2018; 10:1487742. [PMID: 29963294 PMCID: PMC6022223 DOI: 10.1080/20002297.2018.1487742] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Accepted: 05/29/2018] [Indexed: 12/12/2022] Open
Abstract
Periodontitis, rheumatoid arthritis (RA), atherosclerosis (AS), and Alzheimer’s disease (AD) are examples of complex human diseases with chronic inflammatory components in their etiologies. The initial trigger of inflammation that progresses to these diseases remains unresolved. Porphyromonas gingivalis is unique in its ability to secrete the P. gingivalis-derived peptidyl arginine deiminase (PPAD) and consequently offers a plausible and exclusive link to these diseases through enzymatic conversion of arginine to citrulline. Citrullination is a post-translational enzymatic modification of arginine residues in proteins formed as part of normal physiological processes. However, PPAD has the potential to modify self (bacterial) and host proteins by deimination of arginine amino acid residues, preferentially at the C-terminus. Migration of P. gingivalis and/or its secreted PPAD into the bloodstream opens up the possibility that this enzyme will citrullinate proteins at disparate body sites. Citrullination is associated with the pathogenesis of multifactorial diseases such as RA and AD, which have an elusive external perpetrator as they show epidemiological associations with periodontitis. Therefore, PPAD deserves some prominence as an external antigen, in at least, a subset of RA and AD cases, with as yet unidentified, immune/genetic vulnerabilities.
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Affiliation(s)
- Ingar Olsen
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Sim K Singhrao
- Dementia and Neurodegeneration Research Group, Faculty of Clinical and Biomedical Sciences, University of Central Lancashire, Preston, UK
| | - Jan Potempa
- Faculty of Biochemistry, Biophysics and Biotechnology, Department of Microbiology, Jagiellonian University, Kraków, Poland.,Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, KY, USA
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32
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Abstract
PURPOSE OF REVIEW Dysregulated citrullination is a key element that drives the production and maintenance of antibodies to citrullinated proteins, a hallmark in rheumatoid arthritis (RA). This article reviews recent literature on the origin of citrullinated antigens in RA. RECENT FINDINGS The study of synovial fluid from patients with RA has provided important insights into the identity of citrullinated proteins that accumulate in the RA joint (the RA citrullinome) and mechanisms that control their generation. SUMMARY Citrullinating enzymes (peptidylarginine deiminases, PADs) are tightly controlled to limit their hyperactivation. Calcium and redox conditions are important regulators of PAD activity. Studies suggest that citrullination is dysregulated both intra- and extracellularly in RA. In neutrophils, host (i.e., perforin and the membrane attack complex) and bacterial (i.e., toxins) pore-forming proteins induce prominent calcium influx, cytolysis, and hyperactivation of PADs. These factors likely drive hypercitrullination in the RA joint and at extraarticular sites of disease initiation, respectively. As oxidizing conditions present in the extracellular environment are known to inactivate PADs, extracellular citrullination in RA probably requires the constant release of active enzymes from dying cells and may be accelerated by autoantibodies that activate PADs.
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Affiliation(s)
- Erika Darrah
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Felipe Andrade
- Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Bawadekar M, Shim D, Johnson CJ, Warner TF, Rebernick R, Damgaard D, Nielsen CH, Pruijn GJM, Nett JE, Shelef MA. Peptidylarginine deiminase 2 is required for tumor necrosis factor alpha-induced citrullination and arthritis, but not neutrophil extracellular trap formation. J Autoimmun 2017; 80:39-47. [PMID: 28188029 DOI: 10.1016/j.jaut.2017.01.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 01/23/2017] [Accepted: 01/31/2017] [Indexed: 10/20/2022]
Abstract
Citrullination, the post-translational conversion of arginines to citrullines, may contribute to rheumatoid arthritis development given the generation of anti-citrullinated protein antibodies (ACPAs). However, it is not known which peptidylarginine deiminase (PAD) catalyzes the citrullination seen in inflammation. PAD4 exacerbates inflammatory arthritis and is critical for neutrophil extracellular traps (NETs). NETs display citrullinated antigens targeted by ACPAs and thus may be a source of citrullinated protein. However, PAD4 is not required for citrullination in inflamed lungs. PAD2 is important for citrullination in healthy tissues and is present in NETs, but its role in citrullination in the inflamed joint, NETosis and inflammatory arthritis is unknown. Here we use mice with TNFα-induced inflammatory arthritis, a model of rheumatoid arthritis, to identify the roles of PAD2 and PAD4 in citrullination, NETosis, and arthritis. In mice with TNFα-induced arthritis, citrullination in the inflamed ankle was increased as determined by western blot. This increase was unchanged in the ankles of mice that lack PAD4. In contrast, citrullination was nearly absent in the ankles of PAD2-deficient mice. Interestingly, PAD2 was not required for NET formation as assessed by immunofluorescence or for killing of Candida albicans as determined by viability assay. Finally, plasma cell numbers as assessed by flow cytometry, IgG levels quantified by ELISA, and inflammatory arthritis as determined by clinical and pathological scoring were all reduced in the absence of PAD2. Thus, PAD2 contributes to TNFα-induced citrullination and arthritis, but is not required for NETosis. In contrast, PAD4, which is critical for NETosis, is dispensable for generalized citrullination supporting the possibility that NETs may not be a major source of citrullinated protein in arthritis.
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Affiliation(s)
- Mandar Bawadekar
- Department of Medicine, University of Wisconsin, Madison, WI, USA
| | - Daeun Shim
- Department of Medicine, University of Wisconsin, Madison, WI, USA
| | - Chad J Johnson
- Department of Medicine, University of Wisconsin, Madison, WI, USA
| | - Thomas F Warner
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI, USA
| | - Ryan Rebernick
- Department of Medicine, University of Wisconsin, Madison, WI, USA
| | - Dres Damgaard
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Claus H Nielsen
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Ger J M Pruijn
- Institute for Molecules and Materials and Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Jeniel E Nett
- Department of Medicine, University of Wisconsin, Madison, WI, USA; Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
| | - Miriam A Shelef
- Department of Medicine, University of Wisconsin, Madison, WI, USA; William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.
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