title: Enhancement of naturally occurring human spontaneous monocyte-mediated cytotoxicity by cis-diamminedichloroplatinum(II).
abstract: The effect of the antineoplastic agent cis-diamminedichloroplatinum(II) (cis-DDP) on spontaneous cytotoxicity of human mononuclear cells in vitro was assessed. cis-DDP enhanced spontaneous monocyte-mediated cytotoxicity 300% compared to control values. Further, this spontaneous monocyte killing developed earlier (3 to 4 days) than did that of untreated cells (5 to 7 days). Since monocyte cytotoxicity is under the control of lymphocyte suppressor cells, the effect of cis-DDP on separated populations of lymphocytes and monocytes was examined. Unlike X-irradiation which enhanced monocyte cytotoxicity through the indirect pathway of inactivation of lymphocyte suppressors, cis-DDP directly stimulated the monocyte population. Direct stimulation of killer monocytes may be an important mechanism of the antitumor effect of cis-DDP.
mesh_terms: D002469:Cell Separation; D002478:Cells, Cultured; D002945:Cisplatin / Q000494:pharmacology*; D003602:Cytotoxicity, Immunologic / Q000187:drug effects* / Q000528:radiation effects; D006801:Humans; D009000:Monocytes / Q000187:drug effects* / Q000276:immunology / Q000528:radiation effects; D010587:Phagocytosis; D013268:Stimulation, Chemical; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology / Q000528:radiation effects; D014965:X-Rays
chemical_list: D002945:Cisplatin