ABSTRACT
Proteolytic enzymes play a major role in maintaining homeostasis in man through their involvement in a multitude of physiological processes including digestion, coagulation, fibrinolysis, complement activation, intracellular protein turnover, and phagocytosis. Because of the potential for causing tissue damage, however, tight control is placed on the activities of this class of enzyme by protein proteinase inhibitors which strictly regulate their activities. Indeed, it seems clear that the role of inhibitors is twofold. The most important function would appear to be to totally inhibit proteinases which diffuse away from their principal site of action so that nonspecific and, therefore, uncontrolled proteolysis resulting in tissue damage cannot occur. An alternate function, of course, is to regulate proteolysis at a given site of action so that only limited digestion occurs.
