Comparison of histocompatibility antigens on cultured human tumor cells and fibroblasts by quantitative antibody absorption and sensitivity to cell-mediated cytotoxicity.

Human tumor and febroblast tissue culture cells were compared to determine the suitability of fibroblasts as control cells in experiments on human tumor serology and cellular immunology. Fibroblasts expressed the same HL-A antigen profile as did melanoma cells. Furthermore, the quantitative expression of the determinants was similar on both cell types. In four of five pairs tested, the fibroblasts displayed similar sensitivity to effector cells generated by mixed lymphocyte culture as did the tumor cells from the same donor, but there were some differences in the effects of specific alloimmune effector cells at high and low effector-to-target ratios on the two types of target cells. Results indicated that fibroblasts are legitimate control target cells for studies in human tumor immunology, if screening assays are done to verify their antigenicity and sensitivity to cell-mediated cytolysis.