INVITRO AND INVIVO CYTOTOXICITY OF ADRIAMYCIN AND DAUNOMYCIN FOR MURINE MACROPHAGES

Abstract

In vitro exposure of mouse lymphoma cells to adriamycin and daunomycin (DM) for 24 h resulted in comparable cytotoxicity as assessed by viable cell counts and inhibition of DNA synthesis. The spontaneous DNA synthesis of spleen lymphocytes in vitro was also equally affected by the 2 agents. When the in vitro effects of the 2 drugs on macrophage monolayers were investigated, DM was at least 4 times more toxic than AM. In vivo administered DM was more suppressive than AM of Corynebacterium parvum induced spleen macrophage cytotoxicity. The fact that DM is less effective than AM as a cancer chemotherapeutic agent in vivo may be due to the greater destruction of macrophages by DM and a resultant reduction in the contribution of host immunity to antitumor action.