Cytotoxicity of TCL cells under different culture conditions. TCLs were stimulated with CD40-FL in the presence of different cytokine combinations, and cytotoxicity was measured by JAM test. As targets, autologous CD40-FL cells (•), FL cells (▪), autologous CD40-B cells (□), and allogeneic CD40-FL cells (⋄) were used. (A) Cytotoxicity after one stimulation with CD40-FL, (B) after three stimulations with exogenous cytokines added at day 3 of culture, and (C) after three stimulations with exogenous cytokines added at commencement of culture.