Proteases of human leukocytes.

By L. A. MOUNTER AND WASFI ATIYEH T HE EXISTENCE of considerable proteolvtic activities associated with leukocytes has previously been reported, but little characterization of the enzymes has been carried out.13 Experiments with leukocyte preparations using newer enzyme inhibitors are very limited and it seemed probable that improved characterization might result from studies of this type. It was also hoped that the studies might indicate whether leukocyte protease activity could be sufficient to contribute appreciably to the breakdown of damaged tissues invaded by a high concentration of white cells. The present report describes the results of preliminary studies indicating the existence of at least three intracellular proteolytic enzymes in human leukocytes.