{"@type": "dcat:Dataset", "accessLevel": "public", "bureauCode": ["009:25"], "contactPoint": {"@type": "vcard:Contact", "fn": "NIH", "hasEmail": "mailto:info@nih.gov"}, "description": "Interleukin-1 receptor antagonist (IL-1Ra) is a natural IL-1 inhibitor possessing anti-inflammatory properties. IL-1Ra is produced as different isoforms, one secreted (sIL-1Ra) and three intracellular (icIL-1Ra1, icIL-1Ra2 and icIL-1Ra3), derived from the same gene. We examined the production of IL-1Ra species by cultured human articular chondrocytes in response to various cytokines. The levels of IL-1Ra were undetectable in culture supernatants of untreated cells, but were significantly increased by IL-1\u03b2. Cell lysates contained very low levels of IL-1Ra, even in response to IL-1\u03b2, suggesting that chondrocytes produce predominantly sIL-1Ra. IL-6, which had no effect on its own, enhanced the effect of IL-1\u03b2, while dexamethasone prevented the response. We observed by RT-PCR that IL-1\u03b2 and IL-6 induced primarily the production of sIL-1Ra mRNA. Furthermore, IL-1\u03b2 alone or combined with IL-6 increased the levels of nascent unspliced sIL-1Ra mRNA, suggesting that sIL-1Ra expression is regulated at the transcriptional level. Reporter gene assays in immortalized chondrocytes, C-20/A4, consistently showed increased sIL-1Ra promoter activity in response to IL-1\u03b2 and IL-6. In conclusion, human articular chondrocytes produce sIL-1Ra in response to IL-1\u03b2 and IL-6. The production of sIL-1Ra by chondrocytes may have a protective effect against articular inflammatory and catabolic responses.", "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/PMC111027/", "mediaType": "text/html", "title": "Official Government Data Source"}], "identifier": "https://healthdata.gov/api/views/g45v-qsw4", "issued": "2025-07-14", "keyword": ["articular-chondrocytes", "cytokine-response", "il-1ra", "nih", "osteoarthritis-research"], "landingPage": "https://healthdata.gov/d/g45v-qsw4", "modified": "2025-09-06", "programCode": ["009:033"], "publisher": {"@type": "org:Organization", "name": "National Institutes of Health"}, "theme": ["NIH"], "title": "Production of interleukin-1 receptor antagonist by human articular chondrocytes"}