In vitro cytotoxicity of lymphocyte subpopulations against autologous human bladder tumor cells.

The in vitro cytotoxicity of unfractionated blood lymphocytes and T and non-T lymphocytes respectively, was tested against autologous tumor cells from 21 patients with grade III-IV urothelial bladder carcinomas. Generally, little or no cytotoxicity was seen. However, some differences in autologous cytotoxicity between T and non-T lymphocytes were detectable. Four of 21 patients had cytotoxic non-T lymphocytes against autologous bladder tumor cells. The results indicate, that the effector cells are primarily non-T lymphocytes, and that cytotoxicity appears at lower levels of T lymphocytes in unfractionated lymphocyte preparations.