Generation of human cytotoxic T lymphocytes against fresh autologous and allogeneic solid tumors by mixed lymphocyte tumor cell culture with T cell growth factor.

Autologous mixed lymphocyte tumor cell culture (MLTC) induced cytotoxic lymphocytes against autologous tumor cells in 4 out of 14 donors (29%). Further cultivation of MLTC-activated lymphocytes with T cell growth factor (TCGF) resulted not only in the propagation of cytotoxic T lymphocytes (CTL) and an increase of cytotoxicity against autologous tumors, but also in the induction of killer cells against allogeneic tumor cells. Briefly, the results of crisscross tests using fresh tumor cells from 17 donors and lymphocytes from 10 donors indicate that cultivation of MLTC-activated lymphocytes with TCGF generated killer cells against allogeneic tumor cells in most cases, but not against autologous or allogeneic phytohemagglutinin-induced lymphoblasts. These effector cells were mainly OKT3+, OKT8+, OKM1- and Leu7-. Further, the results of cold target inhibition tests undertaken in an autologous tumor killing system suggest that at least 2 different subsets, specifically cytotoxic for autologous tumors and cytotoxic for both autologous and allogeneic tumors, were developed in the CTL induced by autologous MLTC followed by cultivation with TCGF.