In vivo changes of heterogeneity of mouse peritoneal macrophages induced by cis-diamminedichloroplatinum (II) (cis-DDP) and related platinum compounds.

The s.c. injection of cis-DDP into ABD2F1 mice (8 mg/kg b.m.) resulted in alterations of size and surface structure of peritoneal macrophages (PM) and in a reduction of the mean number of Concanavalin A (ConA) binding sites of PM. The PM population of control mice which received physiological saline only consisted of 2 subgroups with a higher and a lower mean ConA binding site number per cell. Contrarily, PM of cis-DDP-treated mice failed the subpopulation with higher ConA binding site number. A loss of this subpopulation was also found in mice treated with platinum salt K2PtCl4 or K2PtCl6. X-ray microanalytically determined elemental contents of PM of control and treated mice showed a correlation between ConA binding site number and cellular concentration of phosphorus or sulphur with the exception of a small group of PM which was characterized by a high content of sulphur and a low number of ConA binding site. This correlation was not found in normal mice.