Serological responses of melanoma patients to vaccines derived from allogeneic cultured melanoma cells
Signal Processing, Computer-Assisted
Twenty melanoma patients were immunized with a whole-cell vaccine prepared from irradiated cells of the melanoma cell line SK-MEL-13. This line, derived from the melanoma of patient AH, expresses a differentiation antigen (initially defined by autologous antibody) which is restricted to melanomas and other cells of neural crest origin. The patients' sera were tested in rosetting assays before and after vaccination for antibodies against cell surface antigens of autologous cultured melanoma cells and SK-MEL-13, and the specificity of observed reactions was defined by absorption tests. Nine patients developed antibodies against autologous cultured melanoma cells. In only one case, patient DM, were these antibodies directed against the AH antigen. In the remaining patients, the antibodies were related to fetal bovine serum in the vaccine growth medium. All patients developed antibodies against cell surface HLA alloantigens of the immunizing cell, SK-MEL-13, as demonstrated by absorption analysis with B cells from the donor of SK-MEL-13 and by serological typing with a panel of HLA typed peripheral blood T cells and B-cell CLL cells. No specificity other than the AH antibody found in patient DM was detected after removal of alloantigens with B cells. We conclude that vaccines prepared from irradiated allogeneic melanoma cells expressing AH antigen, a demonstrably immunogenic differentiation antigen of the melanocyte lineage, are not effective in inducing AH antibody.