The Effect of Synovial Tissue on the Breakdown of Articular Cartilage in Organ Culture

UNLABELLED: Living (pig) cartilage in contact with synovium lost both proteoglycan and collagen and sometimes became reduced to a mass of fibroblast-like chondrocytes without matrix; dead cartilage lost proteoglycan but less collagen. Similar changes appeared in living cartilage grown at a distance from the synovium but in the same dish; dead cartilage was unaffected. CONCLUSION: the synovium has a) a direct, presumably enzymatic action on cartilage matrix and b) an indirect effect mediated through the chondrocytes.