Immunotherapy of an Intramuscular Tumor in Strain-2 Guinea Pigs: Prevention of Tumor Growth by Intradermal Immunization and by Systemic Transfer of Tumor Immunity

Abstract

Immunotherapy of tumor cells inoculated intramuscularly was accomplished by intradermal immunization with living tumor cells. Immunization with cells of the ascites variant of the same tumor cell line resulted in protection of 27% of the animals, and immunization with tumor cells grown in tissue culture resulted in protection of 50% of the animals. Intradermal immunization with frozen-thawed ascites tumor cells, spleen cells, X-irradiated ascites tumor cells, and with tumor cells antigenically unrelated to the challenge inoculum did not prevent growth of the intramuscular tumor. Immunotherapy with intradermal immunization and with systemic transfer of peritoneal exudate cells was effective only when the tumor mass was relatively small. Systemic transfer of immunized peritoneal exudate cells to a tumor-bearing animal prevented tumor growth in 60% of the animals.