Presence of fibronectin in articular cartilage in two animal models of osteoarthritis.

Fibronectin content was determined in articular cartilage in a spontaneous dog model and in a meniscectomy rabbit model of osteoarthritis. Determination of the fibronectin content of urea extracts of articular cartilage by an enzyme linked immunosorbent assay (ELISA) disclosed that degenerated cartilage contained from 10- to 40-fold more fibronectin than normal cartilage. The finding that cartilage fibronectin content was increased in both animal models suggests that elevated cartilage fibronectin content is a general feature of the osteoarthritic process.