Activation of latent collagenase of human leukocytes and gingival fluid by bacterial plaque

Collagenase activity was studied in human leukocytes, gingival crevicular fluid and bacterial plaque, with soluble radioactive collagen as substrate. Inflamed gingiva liberated vertebrate type collagenase into the crevicular fluid in active form. Healthy gingiva, in contrast, released collagenase in a latent form that could be activated by trypsin or plaque. Plaque also stimulated leukocytes to release collagenase, and activated the latent enzyme.