Generation of cytotoxic antibodies to the B16 murine melanoma using a formalinized vaccine

The goal of our experiments was to determine the extent to which the humoral response to a melanoma vaccine elicits the production of cytotoxic antibodies in tumor‐challenged mice. Mice were immunized with a vaccine produced from formalinized extracellular antigens (FECA) derived from B 16 F 10 melanomas. The production of antibodies that recognized the vaccine preparation was determined by ELISA, as was their cross‐reactivity with the B700 melanoma,antigen. The antibodies were shown to be anti‐proliferative by inhibition of tritiated thymidine incorporation into the DNA of cultured target cells and cytotoxic by assays for complement‐mediated and antibodydependent cellular cytotoxicity. Flow cytometric analyses indicated that‐60% of the target cells specifically bound antibody from the immune sera. These results confirm that B700 is a significant antigenic component of the FECA vaccine, and provide encouragement for this approach to developing useful melanoma vaccines.