[Identification and characterization of effector lymphocytes lysing autologous tumor cells]

Effector lymphocytes cytotoxic to autologous tumor cells consist of heterogeneous populations. In this communication, we have presented the results of experiments, in which these heterogeneous effector cells were classified based on their surface markers and modes of differentiation depending upon culture conditions. NK cells with a typical phenotype of CD2+ 3-16+ were one of major populations, which could respond to IL-2 and be differentiated into lymphokine activated killer (LAK) cells. LAK cells were also induced from a CD3+4-8- T cell subset by IL-2 stimulation. Effector cells with a phenotype of CD2+ 3-4-8-16-, which may belong to the T cells at early stages of differentiation, could also be induced by stimulation of immunoadjuvants. Finally, it was shown that the effector cells with a typical phenotype of cytotoxic T lymphocytes, CD3+4-8+16-, and a non-MHC-restricted cytotoxicity were induced by IL-2 in the tumor infiltrating lymphocytes.