ABSTRACT
OBJECTIVE: To determine the influence of IL-1 beta on the presence and the distribution of tenascin in matrix of human normal and osteoarthritic cartilage explants. METHODS: Cartilage was grown in organotypic culture with or without IL-1 beta (10 ng ml1). Tenascin antigen was detected on cryopreserved cartilage sections by immunohistochemical techniques with a monoclonal antibody directed against all tenascin isoforms (BC-4), and then quantified by video imaging densitometry. RESULTS: Tenascin was present in normal cartilage explants and increased in osteoarthritic cartilage explants. Treatment of normal and osteoarthritic cartilage explants with IL-1 beta (10 ng ml-1) induced an increase in tenascin content, which was particularly high in normal cartilage and predominated in the superficial layers of damaged cartilage. There was no obvious correlation between proteoglycan loss and presence of tenascin. CONCLUSIONS: In human normal and osteoarthritic cartilage explants, the presence and the distribution of tenascin are influenced by IL-1 beta.
Subject(s)
Cartilage, Articular/metabolism , Interleukin-1/pharmacology , Osteoarthritis/metabolism , Tenascin/metabolism , Aged , Cartilage, Articular/chemistry , Culture Techniques , Densitometry , Female , Humans , Image Processing, Computer-Assisted , Immunohistochemistry , Male , Tenascin/analysisABSTRACT
It is generally agreed that gingival overgrowth results from an increase in the levels of gingival extracellular macromolecules infiltrated with various numbers of inflammatory cells. The relative amounts of extracellular matrix macromolecules observed in 12 cases of gingival hyperplasia associated with the use of cyclosporin, hydantoin or nifedipine were compared with those obtained in a control group on the basis of histological and immunohistochemical investigations. From tissue sections, the quantification was by computerized morphometric analysis on a BFM 186 microcomputer to which were implemented the transformations of mathematical morphology. The area fractions (AA%) occupied by total collagen, type III and type IV collagen, vessels, fibroblasts, fibronectin and elastic fibres were estimated and compared. The overall histological aspects of drug-induced gingival overgrowth were similar, but quantification of different extracellular matrix components showed differences. In the nifedipine and cyclosporin groups, the area occupied by fibroblasts were not significantly greater than in healthy gingiva and chronic gingivitis. The area occupied by collagen was significantly greater in the nifedipine group than in the other pathological groups. Fibronectin was also strongly expressed in the nifedipine group, and the elastic fibre network was preserved in this group.
