Production of lymphokine-activated lymphocytes. Lysis of human head and neck squamous cell carcinoma cell lines.

Lymphokine-activated killer cells are thought to be important mediators of host tumor defense. In the present study, the cytotoxic potential of lymphokine-activated lymphocytes against different head and neck squamous cell carcinoma cell lines was investigated. Lymphokine-activated killer cells were derived from peripheral blood lymphocytes. Effector peripheral blood lymphocyte cell suspensions were incubated in the presence or absence of recombinant interleukin-2. Cytotoxicity of incubated cells or fresh peripheral blood lymphocytes was determined in a 3-hour chromium 51 release assay. Target cell lines included K562 (a natural killer-sensitive target) and the following head and neck squamous cell carcinoma cell lines: Cal 27, UMSCC-1, UMSCC-8, UMSCC-16, UMSCC-19, and UMSCC-22a. Fresh peripheral blood lymphocytes and peripheral blood lymphocytes cultured in the absence of added interleukin-2 demonstrated minimal cytotoxic effects against the squamous cell carcinoma targets. In contrast, these fresh and incubated lymphocytes showed significant cytotoxic effects against K562. Cells preincubated in the presence of interleukin-2 demonstrated a statistically significant increase in cytotoxic effects against K562 and all squamous cell carcinoma targets. These investigations support the possible role of lymphokine-activated killer cells in host defense against squamous cell carcinoma. In vitro natural killer cell activity against head and neck squamous cell carcinoma cell lines is low; however, significant lymphokine-activated killer cell cytotoxicity is present.