Antibody formation for malignant tumor. II. Antigenicity of Ehrlich ascites tumor lipoprotein

A unique low density lipoprotein was obtained from the tumor transplanted with a cultured cell line of Ehrlich ascites tumor, JTC-ll cell. The tumor low density lipoprotein electrophoretically migrated as a single band, and the mobility was different from that of other organs. The chemical composition of lipid, cholesterol and phospholipids in tumor low density lipoprotein were characteristic. The flotation rate was Sf 5.9, and thus the molecular weight was estimated to be about 130 x 104. The inhibitory effect on tumor growth of the immune serum was most elevated at 25th day after the intraperitoneal administration of tumor low density lipoprotein. The main fraction effective for inhibition of tumor growth existed in γ-globulin.