Identification of a HERV-K env surface peptide highly recognized in Rheumatoid Arthritis (RA) patients: a cross-sectional case-control study.
Endogenous retroviruses (HERV) are believed to be pathogenic in several autoimmune diseases. Among them, HERV-K viruses have been reported recently to be involved in the pathogenesis of rheumatoid arthritis (RA). In this study we have explored the role of humoral immune response against HERV-K as a potential pathogenetic mechanism in RA. Four different peptides from the extracellular portion of the env protein of HERV-K (env-su19-37, env-su109-126, env-su164-186, env-su209-226) were selected by bioinformatic analysis on the basis of their putative immunogenicity. Indirect enzyme-linked immunosorbent assay (ELISA) was then carried out to quantify antibodies against those peptides on blood samples of 70 consecutive RA patients and 71 healthy controls (HC). Differences between the two groups were analysed using the Mann-Whitney test. Potential correlations between RA laboratory, clinical descriptors and immunoglobulin (Ig)G levels were explored by bivariate regression analysis. Serum autoantibodies against one of four tested peptides of HERV-K (env-su19-37) were significantly higher in RA than in HC (19 versus 3%, P = 0·0025). Subgroup analysis showed no association between anti-HERV-K peptide humoral response and clinical, serological and clinimetric RA disease descriptors. Serum from RA patients in our series reacted significantly against HERV-K env-su19-37peptide in comparison to the general population suggesting a role for the HERV-K- related, secondary antigenic-driven immune response in the pathogenesis of RA. Further studies are needed to confirm these results and to explore the role of this HERV-K surface peptide as a potential therapeutic target.
Dipartimento di Scienze Biomediche, Microbiologia Clinica e Sperimentale, Università degli Studi di Sassari, Sassari, Italy.
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Mameli
Dipartimento di Medicina Clinica e Sperimentale, Cattedra e Unità di Reumatologia, Università e AOU di Sassari, Sassari, Italy.
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Erre
Dipartimento di Scienze Biomediche, Microbiologia Clinica e Sperimentale, Università degli Studi di Sassari, Sassari, Italy.
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Caggiu
Dipartimento di Medicina Clinica e Sperimentale, Cattedra e Unità di Reumatologia, Università e AOU di Sassari, Sassari, Italy.
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Mura
Dipartimento di Scienze Biomediche, Microbiologia Clinica e Sperimentale, Università degli Studi di Sassari, Sassari, Italy.
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Cossu
Dipartimento di Scienze Biomediche, Microbiologia Clinica e Sperimentale, Università degli Studi di Sassari, Sassari, Italy.
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Bo
Dipartimento di Scienze Biomediche, Microbiologia Clinica e Sperimentale, Università degli Studi di Sassari, Sassari, Italy.
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Cadoni
Dipartimento di Medicina Clinica e Sperimentale, Cattedra e Unità di Reumatologia, Università e AOU di Sassari, Sassari, Italy.
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Piras
Dipartimento di Medicina Clinica e Sperimentale, Cattedra e Unità di Reumatologia, Università e AOU di Sassari, Sassari, Italy.
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Mundula
Dipartimento di Medicina Clinica e Sperimentale, Cattedra e Unità di Reumatologia, Università e AOU di Sassari, Sassari, Italy.
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Colombo
Dipartimento di Medicina Clinica e Sperimentale, Cattedra e Unità di Reumatologia, Università e AOU di Sassari, Sassari, Italy.
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Buscetta
Dipartimento di Medicina Clinica e Sperimentale, Cattedra e Unità di Reumatologia, Università e AOU di Sassari, Sassari, Italy.
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Passiu
Dipartimento di Scienze Biomediche, Microbiologia Clinica e Sperimentale, Università degli Studi di Sassari, Sassari, Italy.
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0000-0003-0566-2049
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Sechi
D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D020077:Endogenous Retroviruses / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D056724:Immunity, Humoral; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D010455:Peptides / Q000276:immunology; D014759:Viral Envelope Proteins / Q000276:immunology*
D000914:Antibodies, Viral; D001323:Autoantibodies; D007074:Immunoglobulin G; D010455:Peptides; D014759:Viral Envelope Proteins
Herv-K; humoral response; molecular mimicry; peptides; rheumatoid arthritis