Malignant melanoma: specific immunity induced by bacillus Calmette-Guérin in BALB-c mice.

Previous treatment of BALB/c mice with bacillus Calmette-Guérin (BCG) will significantly protect them against intramuscular challenge of S-91 melanoma but not against a mammary carcinoma or a methylcholanthrene-induced sarcoma. Lymphocyte-mediated cytotoxicity studies correlate with in vivo data in showing that BCG-immune lymphocytes are specifically cytotoxic to S-91 melanoma target cells but not to the carcinoma or sarcoma target cells.