Role of medullasin in granulocytes in biophylaxis. Elastinolytic activity and the potentiation of cytostatic activity of human monocytes.

Medullasin, a serine protease in bone marrow cells, resembles elastase, but is essentially devoid of elastinolytic activity. The protease revealed elastinolytic activity when small amounts of other proteases such as trypsin, papain, chymotrypsin, or collagenase coexisted in the incubation mixture. In vitro treatment of human monocytes with medullasin caused an increment of their cytostatic activity. Since medullasin failed to increase the cytostatic activity in the supernatant of monocytes, the enhancement of cytostatic activity of monocytes by medullasin is considered to be not mediated through the production of soluble factors from monocytes.