{"@type": "dcat:Dataset", "accessLevel": "public", "bureauCode": ["009:25"], "contactPoint": {"@type": "vcard:Contact", "fn": "NIH", "hasEmail": "mailto:info@nih.gov"}, "description": "An excess of the proinflammatory substance IL-18 is present in joints of patients with rheumatoid arthritis (RA), and expression of IL-18 receptor (IL-18R) regulates IL-18 bioactivity in various cell types. We examined the expression of IL-18R \u03b1-chain and \u03b2-chain and the biologic effects of IL-18 in fibroblast-like synoviocytes (FLS) after long-term culture. The presence of both IL-18R chains was a prerequisite for IL-18 signal transduction in FLS. However, all FLS cultures studied were either resistant or barely responsive to IL-18 stimulation as regards cell proliferation, expression of adhesion molecules ICAM-1 and vascular cell adhesion molecule (VCAM)-1, and the release of interstitial collagenase and stromelysin, IL-6 and IL-8, prostaglandin E2, or nitric oxide. We conclude that the presence of macrophages or IL-18R+ T cells that can respond directly to IL-18 is essential for the proinflammatory effects of IL-18 in synovitis in RA.", "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/PMC83844/", "mediaType": "text/html", "title": "Official Government Data Source"}], "identifier": "https://healthdata.gov/api/views/rxdp-m9n5", "issued": "2025-07-14", "keyword": ["nih", "rheumatoid-arthritis", "il-18-receptor", "synovial-inflammation", "fibroblast-synoviocytes"], "landingPage": "https://healthdata.gov/d/rxdp-m9n5", "modified": "2025-09-06", "programCode": ["009:037"], "publisher": {"@type": "org:Organization", "name": "National Institutes of Health"}, "theme": ["NIH"], "title": "Expression of interleukin-18 receptor in fibroblast-like synoviocytes"}