Cytotoxic antibodies to cultured melanoma cells in the sera of melanoma patients.

By means of the complement-dependent microcytotoxicity test, cytotoxic antibodies to melanoma cells in long-term culture were detected in 34 of 90 sera from melanoma patients. The incidence of cytotoxic antibodies in melanoma patients was significantly greater than in subjects free of malignant disease but not significantly greater than in patients with other types of cancer. The sera were cytolytic to melanoma cells only in conjunction with rabbit complement, and they reacted with the pabel of melanoma cells in a distinct fashion. No association was found between presence of cytotoxic antibodies and the occurrence of metastasis.