INFLUENCE OF INTERLEUKIN-1-BETA ON TENASCIN DISTRIBUTION IN HUMAN NORMAL AND OSTEOARTHRITIC CARTILAGE - A QUANTITATIVE IMMUNOHISTOCHEMICAL STUDY

Objective - To determine the influence of IL-1 beta on the presence an d the distribution of tenascin in matrix of human normal and osteoarth ritic cartilage explants. Methods - Cartilage was grown in organotypic culture with or without IL-1 beta (10 ng ml(1)). Tenascin antigen was detected on cryopreserved cartilage sections by immunohistochemical t echniques with a monoclonal antibody directed against all tenascin iso forms (BC-4), and then quantified by video imaging densitometry. Resul ts - Tenascin was present in normal cartilage explants and increased i n osteoarthritic cartilage explants. Treatment of normal and osteoarth ritic cartilage explants with IL-1 beta (10 ng ml(-1)) induced an incr ease in tenascin content, which was particularly high in normal cartil age and predominated in the superficial layers of damaged cartilage. T here was no obvious correlation between proteoglycan loss and presence of tenascin. Conclusions - In human normal and osteoarthritic cartila ge explants, the presence and the distribution of tenascin are influen ced by IL-1 beta.