Lymphokine activated killer (LAK) cells in patients with gastrointestinal cancer.

Lymphokine activated killer (LAK) cells are a recently described cellular immune phenomenon with exciting potential for the treatment of tumours arising from solid organs. A comparison of some aspects of LAK cell precursors and LAK cell function was undertaken in 44 control subjects and 44 preoperative patients suffering from gastrointestinal cancer (20 localised and 24 advanced). Lymphokine activated killer cell precursor (natural killer (NK) cell) activity was significantly diminished in patients with advanced tumours (p less than 0.02) as was fully mature LAK cell activity against an NK resistant target cell (p less than 0.012). T-lymphocyte responses were not significantly different between the three groups. The reduced LAK cell generation was associated with a significantly diminished proliferative response of LAK precursors to stimulation with high dose IL-2 in vitro (p less than 0.012). Impaired LAK cell generation may explain the failure of adoptive cellular immunotherapy with LAK cells in some patients with advanced gastrointestinal cancer and prompts the search for means of augmenting this activity in such patients.