{"@type": "dcat:Dataset", "accessLevel": "public", "bureauCode": ["009:25"], "contactPoint": {"@type": "vcard:Contact", "fn": "NIH", "hasEmail": "mailto:info@nih.gov"}, "description": "Most patients with rheumatoid arthritis (RA) express HLA-DR4, HLA-DR1 or HLA-DR10. These alleles share a common amino acid motif in their third hypervariable regions: the shared epitope. In normals and patients with RA, HLA-DR genes exert a major influence on the CD4 \u03b1\u03b2 T-cell repertoire, as shown by studies of AV and BV gene usage and by BV BJ gene usage by peripheral blood CD4 \u03b1\u03b2 T-cells. However, the rheumatoid T-cell repertoire is not entirely under HLA-DR influence, as demonstrated by discrepancies in VB JB gene usage between identical twins discordant for RA and by contraction of the CD4 \u03b1\u03b2 T-cell repertoire in RA patients. Shared epitope positive HLA-DR alleles may shape the T-cell repertoire by presenting self peptides to CD4 T cells in the thymus. Peptides processed from HLA-DR molecules and encompassing the shared epitope may also be presented by HLA-DQ and select CD4 \u03b1\u03b2 T cells in the thymus. Thus, shared epitope-positive alleles impose a frame on the T-cell repertoire. This predisposing frame is further modified (by unknown factors) to obtain the contracted rheumatoid repertoire.", "distribution": [{"@type": "dcat:Distribution", "description": "Visit the original government dataset for complete information, documentation, and data access.", "downloadURL": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC130006/", "mediaType": "text/html", "title": "Official Government Data Source"}], "identifier": "https://healthdata.gov/api/views/jfx7-rdvs", "issued": "2025-07-14", "keyword": ["hla-dr4", "nih", "rheumatoid-arthritis", "shared-epitope", "t-cell-repertoire"], "landingPage": "https://healthdata.gov/d/jfx7-rdvs", "modified": "2025-09-06", "programCode": ["009:048"], "publisher": {"@type": "org:Organization", "name": "National Institutes of Health"}, "theme": ["NIH"], "title": "Association of MHC and rheumatoid arthritis: Association of RA with HLA-DR4 - the role of repertoire selection"}