Latent collagenase of rheumatoid synovial fluid is not of granulocytic origin

The physicochemical properties of three latent collagenases derived from rheumatoid synovial fluid, polymorphonuclear leucocytes and culture medium of rheumatoid synovium were compared. It has been shown that synovial fluid enzyme is similar to that of synovium collagenase from tissue culture and differs significantly in molecular size and protein charge from granulocyte collagenase. The results indicate that the latent, trypsin-activable collagenase present in rheumatoid synovial fluid is not of granulocytic origin and seems to derive from the synovial membrane.