In vitro effects of protease inhibitors on murine natural killer cell activity.
To test whether proteolytic events are involved in natural killer (NK) cell mediated lysis of tumour cells, twenty-three different protease inhibitors were added to in vitro assays of natural killer cell reactivity. Of all of the materials tested, only tosyl-L-lysine chloromethyl ketone (TLCK), tosyl-L-phenylalanine chloromethyl ketone (TPCK) and benzamidine unequivocally inhibited killing at concentrations approaching those needed to affect appropriate purified proteases. All of the effective inhibitors, and none of the others tested, inhibited binding of effector to target cells. The action of TLCK was focused on both effector and target cells, in that cytolysis was completely inhibited by a 1 hr pretreatment of effectors with 10(-4) M TLCK, and 60% inhibited by a 1 hr treatment of targets only.
D000818:Animals; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D007694:Killer Cells, Natural / Q000187:drug effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008970:Molecular Weight; D011480:Protease Inhibitors / Q000494:pharmacology*; D013997:Time Factors; D014107:Tosyllysine Chloromethyl Ketone / Q000494:pharmacology; D014108:Tosylphenylalanyl Chloromethyl Ketone / Q000494:pharmacology
D011480:Protease Inhibitors; D014107:Tosyllysine Chloromethyl Ketone; D014108:Tosylphenylalanyl Chloromethyl Ketone