Tumor-Specific Antigen(s) in a Spontaneous Mammary Carcinoma of C3H Mice. II. Active Immunization of Mammary-Tumor-Agent-Free Mice

(C57BL × C3H/He)F1 mice,which do not carry a mammary tumor agent (MTA) that induces development of breast carcinoma, were actively immunized by: 1) three injections of radiation-killed tumor cells at weekly intervals, Freund' s adjuvant being included in the first injection, or 2) a tumortransplant allowed to growto ≈ 250 mm3 and then exposed to a tumor lethal dose of X radiation. In both instances, this immunity was adoptively transferred. Normal spleen and lymph node cells were not effective in immunizing against the tumor. These results contrasted with those from studies based on C3H/He and (C3H/He × C57BL)F1 mice which do carry the MTA. In these animals immunization against subsequent challenge to the mammary carcinoma was not achieved. Tests for presence of enhancing or cytotoxic antibodies in sera of (C57BL × C3H/He)F1 mice bearing a transplanted mammary carcinoma were negative.