Human Latent PMN Leukocyte Collagenase and Regulation of Activity via Disulfide-Thiol Interchange as Catalyzed by the Glutathione Cycle

Since the initial demonstration of collagenolytic activity in leukocytes [1], it has been shown that the enzyme exists in both active and latent forms in extracts of human leukocytes [2], The latent collagenase can be activated by other active neutral proteinases [3–5] with a concomitant decrease in molecular weight of 10,000–20,000. In previous years various proteolytic enzymes have been used by many groups to activate latent collagenases obtained from a variety of other tissues and a multistep scheme has been proposed for collagenase activation by limited proteolysis [6–9].