THE FATE OF HUMAN POLYMORPHONUCLEAR LEUKOCYTE AMINOPEPTIDASES UPON CELL STIMULATION WITH PHAGOCYTIC AND CHEMICAL STIMULI

1. After being treated with nonopsonized zymosan A or phorbol-12-myristate-13-acetate, human polymorphonuclear leukocytes release aminopeptidases together with granules marker-enzymes and vitamin B-12-binding protein. 2. Chemotactic peptide, fMet-Leu-Phe and its analogs, fMet-Phe, fMet-Ala and fMet-Leu-Phe-Lys have a similar effect. 3. By their isoelectric point determinations the released aminopeptidases correspond to the enzymes from granules. Among aminopeptidases released the highest activities were those toward methionine- and alanine-2-naphthylamide and the lowest one toward arginine-2-naphthylamide.