BENEFICIAL-EFFECTS OF MYRISTIC, STEARIC OR OLEIC-ACID AS PART OF LIPOSOMES ON EXPERIMENTAL-INFECTION AND ANTITUMOR EFFECT IN A MURINE MODEL

Liposomes consisting of dicetyl-phosphate, cholesterol, lecithin and s tearic or myristic or oleic acid, exert a protective effect for mice a gainst experimental infection by Salmonella typhimurium, and delay bot h the onset and mortality B16 melanoma in these animals. Liposomes lab elled with H-3-myristic acid were used as probes in the spleen and liv er. We found that the treatment schedule rather than route of administ ration of liposomes, is important. The results show that in order to i nduce protection, preventive treatment must start at least three days before. Longer treatments do not increase the degree of protection, an d treatments started at the same time as or following experimental inf ection or tumor transplantation, have no effect.