Detection of cytotoxicity of freshly obtained lymphocytes and of lymphocytes activated with recombinant interleukin II (rIL-2) against lung cancer cell lines by human tumor clonogenic assay (HTCA).

The cytotoxicity of freshly obtained human peripheral blood lymphocytes and lymphocytes activated with human recombinant interleukin II (rIL-2) was evaluated against lung cancer cell lines by the human tumor clonogenic assay. Colony formation of all human lung cancer cell lines, PC-1, 3, 6, 7, 9, 13 and 14 were suppressed by lymphocytes activated with 100 units/ml of human rIL-2 for 72 hr. However, the degree of the suppression of colony formation by lymphocytes activated with rIL-2 was different for each cell line. The per cent inhibition of colony formation obtained by HTCA correlated well with the per cent cytolysis obtained by 51Cr-release assay for all cell lines. HTCA provides a very useful tool for the detection of cytotoxicity of lymphocytes against clonogenic tumor cells.