Characterization of type V collagenase (gelatinase) in synovial fluid of patients with inflammatory arthritis.

Gelatin degrading matrix metalloproteinases in synovial fluid from 21 patients with inflammatory arthritis were shown to consist of two distinct gene products, 92 and 70 kDa gelatinases. The gelatinolytic activity of 92 kDa enzyme, which is released from stimulated neutrophils, was positively correlated to neutrophil count in the fluid. By contrast, 70 kDa molecule did not correlate with neutrophil cell count. Purification of these enzymes revealed they could degrade type XI collagen, a cartilage component resistant to interstitial collagenase. The elevated levels of 92 kDa gelatinase in rheumatoid arthritis samples compared to osteoarthritis suggest a role of this enzyme in cartilage destruction.