title: Enhancement of natural killer cytotoxicity by cis-diamminedichloroplatinum (II) in vivo and in vitro.
abstract: To investigate the immunomodulating properties of cis-diamminedichloroplatinum (II) (CDDP), we studied the drug's effects on natural killer (NK) lymphocyte cytotoxicity. i.p. injections of CDDP (2-6 mg/kg) into adult mice significantly enhanced cytolysis of YAC-1 and K562 targets mediated by peritoneal and spleen cells. Lysis of the NK-resistant targets P815, EL-4, MOT, and RAJI was not increased, nor was the lysis of a YAC variant which had been specifically rendered resistant to NK lysis. Activated cytotoxicity was first noted 24 h after injection and returned to baseline by 7 days. Although i.p. injection enhanced peritoneal and spleen cell lysis, i.v. injection only activated spleen cells. Two analogues of CDDP, carbo- and iproplatin, effectively enhanced NK activity, but transplatin had no effect. Activated effector cells were non-adherent to nylon wool and serum-coated plates; they co-separated with lymphocytes on Percoll gradients, and they expressed asialo GM1 determinants. Incubation of targets with CDDP for 1 or 18 h significantly increased their sensitivity to lysis by normal murine spleen cells. These data indicate that CDDP has potent effects on NK cytotoxicity.
mesh_terms: D000818:Animals; D002945:Cisplatin / Q000494:pharmacology* / Q000627:therapeutic use; D003131:Combined Modality Therapy; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007113:Immunity, Innate / Q000187:drug effects*; D007694:Killer Cells, Natural / Q000276:immunology*; D051379:Mice; D009374:Neoplasms, Experimental / Q000188:drug therapy / Q000628:therapy*; D013997:Time Factors
chemical_list: D002945:Cisplatin