Antigens on melanoma cells detected by leukocyte dependent antibody assays of human melanoma antisera.
Antibody-dependent cell-mediated cytotoxic assays have been used to examine antigens on human melanoma cells obtained either directly from patients or from long-term melanoma cell lines. A panel of melanoma antisera was selected from human subjects which could be shown not to have significant reactivity to histocompatibility antigens. With these antisera extensive cross-reactions between melanoma cells were found. However, the cross-reactivity was incomplete and the pattern of reactivity was different for each antiserum tested. These results were not consistent with a common melanoma antigen on human melanoma cells but rather indicated heterogeneity of melanoma antigens and multiple antibody specificities in the sera tested. This appeared to be confirmed by extensive cross-absorption studies which indicated limited cross-reactivity of antigens on melanoma cells from either long-term or short-term cultures. Several changes in the antigenic profile of melanoma cells in vitro from both long-term and short-term cultures were documented which resulted from contamination of the melanoma cell lines with non-melanoma cells and fibroblasts. Melanoma antisera may therefore be useful to mintor changes in long-term cultures which would otherwise give spurious results in in vitro tests. These results appear to have considerable significance for understanding tumour/host relationships and for the establishment of rational immunotherapeutic procedures and diagnostic tests in melanoma.
D000906:Antibodies; D000918:Antibody Specificity; D000951:Antigens, Neoplasm / Q000032:analysis*; D002460:Cell Line; D003429:Cross Reactions; D003601:Cytotoxicity Tests, Immunologic; D000939:Epitopes; D006649:Histocompatibility Antigens; D006801:Humans; D007106:Immune Sera; D007962:Leukocytes / Q000276:immunology; D008545:Melanoma / Q000276:immunology*; D013997:Time Factors
D000906:Antibodies; D000951:Antigens, Neoplasm; D000939:Epitopes; D006649:Histocompatibility Antigens; D007106:Immune Sera