Lysis of lymphoma cells by autologous and allogeneic natural killer cells

Studies were undertaken to determine whether natural killer (NK) cells would lyse autologous and allogeneic lymphoma cells. When large granular lymphocytes, which are known to mediate NK activity, were enriched from peripheral blood and used as effector cells, they lysed autologous lymphoma cells of all of eight patients tested, and those of healthy donors lysed lymphoma cells of all of ten patients tested. The addition of interferon to the culture medium enhanced their cytotoxicity in three of the eight patients in the autologous effector- tumor system and in four of the ten patients in the above allogeneic system. On the basis of the unlabeled target competition test and the decrease in cytotoxicity with anti-NK antibody treatment, NK cells appeared to be the main cytotoxic effector cells for autologous and allogeneic lymphoma cells.