Lymphokine-activated killer cytotoxicity against leukaemic blast cells.

While the sensitivity of cell lines and solid tumours to lymphokine-activated killer (LAK) cell cytotoxicity is extensively reported, the ability of these generated cytotoxic cells to lyse leukaemic blast cells is controversial. This study reports the successful generation of LAK cells with specificity for leukaemic blast cells. Control donors, patients in remission and patients with active leukaemia were capable of lysing allogeneic leukaemic blast cells. One patient was also capable of lysing autologous leukaemic blast cells. Successful LAK generation was achieved by the use of high dose recombinant interleukin-2 (rIL-2) while combinations of lymphokines did not improve LAK specificity or efficacy. These findings suggest that LAK immunotherapy may be considered for the treatment of patients with acute leukaemia.