Human tumor-lymphocyte interaction in vitro. VI. Specificity of primary and secondary autologous lymphocyte-mediated cytotoxicity.

A T-cell-enriched lymphocyte subset of samples from 15 tumor patients was tested for primary cytotoxicity against autologous tumor cell preparations and against 1-3 different allogeneic tumor cell preparations from biopsy material. Allogeneic cytotoxicity occurred in only 1 of 10 patients with autologous reactivity. The lymphocytes of 14 patients were cultured with autologous cells from biopsy material for 6 days. These lymphocytes killed autologous targets, but only 1 patient's lymphocytes were cytotoxic against 1 of the 4 allogeneic tumors tested. Cocultivation with allogeneic cells from biopsy specimens generated cytotoxicity toward the sensitizing allogeneic cells in 3 of 9 test combinations. In 2 of 3 instances the effectors were also active against the autologous tumor cells. Cytotoxicity in primary and secondary tests occurred thus only rarely against allogeneic targets. This indicated either the presence of individual tumor-related antigens on the cells from biopsy material or reflected the histocompatibility restriction of T-cell-mediated cytotoxicity.