Human collagenases: comparative and immunolocalization studies.

Four human collagenases derived from different tissues or cells were shown to have different physicochemical properties with regard to molecular size and protein charge. Such differences have been used to demonstrate that the collagenase activity of rheumatoid synovial fluids is of granulocytic origin. Immunolocalization studies have demonstrated that immunoreactive collagenase is present in a variety of human tissues. Its production by cells in normal tissues suggests a role in collagen remodelling processes, whereas its more frequent occurrence in diseased tissues suggests an important role in pathological collagen resorption. In nearly all the positive specimens examined the enzyme was restricted to a single cell or small groups of cells, or collagenous elements, suggesting microenvironmental rather than widespread collagenolytic activity.