[Effect of soedomycin (M3) on the phagocytosis in the mouse (author's transl)]

Effect of M3, an anticancer agent, on the phagocytic activity of the mouse reticuloendothelial system was studied by the carbon clearance method. Lysosomal enzyme activities of peritoneal exudate cells solution (PECs) and peritoneal macrophage (Mp), and morphological changes of Mp were also examined. The K index (phagocytic index) was significantly increased 24 hr after the administration of M3 (250,300 mg/kg, i.p. X 3) as well as that of zymosan (Z: 50 mg/kg, i.p. X 3). The time course on phagocytic activity of Me (300 mg/kg) was also investigated. The index was increased 2, 4, and 96 hr after i.p. administration, but on i.v. administration the index was decreased at 2 and 4 hr, although increased at 72 hr. Microscopically, carbon particles were internalized by Mp of marginal zones between white and red pulp in the spleen, and in the liver, mainly by Kupffer cells. Lysosomal enzyme activities (acid phosphatase and beta-glucuronidase) and cell numbers of PECs were increased as follows: Z greater than M3 greater than Na2HPO4. These enzyme activities in Mp were also increased significantly 72 and 96 hr after i.p. administration. Observing of morphology by Giemsa staining, saline and Na2HPO4 groups showed round monocytes, but in the M3 and Z groups there were enlarged cells with many projections. These results suggest that M3 promotes the phagocytic activity on the reticuloendothelial system in mice and has a stimulatory effect on Mp because of the increase in the lysosomal enzyme activities and morphological changes in the cells.