Addition of exogenous cytokines does not rescue TSA-treated cells. (A) Effect of IL-2 on cell survival. CD4+ T-cells were isolated by magnetic cell separation from C57BL/6 mouse splenocytes and cultured in medium containing 100 nM TSA (+TSA) or DMSO alone (-TSA) for 20 hours in the presence of growing concentrations of rmIL-2 (0–200 U/ml). Cell survival of TSA-treated cells is plotted in the right coordinates axis whereas that of non-treated cells is plotted in the left axis. (B) Effect of exogenous cytokine addition on cell survival. CD4+ T-cells were cultured in medium containing TSA at growing concentrations (+TSA) or DMSO alone (-TSA) and in the presence of various cytokines or stimuli (legend inset in graphic). PI staining of nuclei determined cell survival after 20 hours. Shown is the mean percentage of survival; bars represent SD. All data are representative of three independent experiments.