Pre- and postirradiation hemopoietic effects of liposomal muramyl tripeptide phosphatidylethanolamine (MTP-PE) administered to C57Bl/6 mice before irradiation.

The effect of muramyl tripeptide (MTP-PE) encapsulated in liposomes (multilamellar vesicles, MLV) on hemopoiesis and hemopoietic recovery after sublethal single irradiation with a dose of 6 Gy was investigated. MTP-PE/MLV during 24 h after administration stimulated the monocyte/macrophage system and accelerated recovery from radiation-induced damage of hemopoiesis. The above reparative processes were accompanied by hyperplasia of granulocytes in the bone marrow on days 6-8 after irradiation, acceleration of erythropoiesis in the spleen and recovery of granulocyte count in the peripheral blood. The repair of thymic and splenic lymphoid tissues as well as recovery of the number of mononuclear cells in peripheral blood was not influenced by MTP-PE/MLV application.