Abstract

Studies were undertaken to determine whether in vitro-propagated large granular lymphocytes (LGL), which are known to mediate natural killer (NK) activity, would lyse autologous and allogeneic lymphoma cells. LGL from ten patients and two healthy donors were propagated in vitro for two to four weeks with interleukin 2-containing medium, and their cytotoxicity was tested in a 5-h 51Cr-release assay. Cultured LGL from all the patients and healthy donors demonstrated strong cytotoxicity against K562 target cells, a standard target in NK assay, while cultured LGL from the patients lysed autologous lymphoma cells from three of the ten patients tested and those of the two healthy donors lysed lymphoma cells from four of the ten patients. These findings indicate that, when LGL propagated in vitro in large numbers show lytic activity against autologous lymphoma cells, these LGL may have potential application in clinical trials.