Short-term and multidose treatment.

(A) Short-term treatment (“pulsing”) of Fas-transduced T cells with AP1903. LV′VFas-transduced primary human T lymphocytes were incubated with 10 nM AP1903 for 1, 2, or 4 hours and were washed extensively, and survival was assayed after 24 (open bars) or 48 (shaded bars) hours, as described in “Materials and methods.” As a control, cells were incubated in the absence of AP1903 (−) or in the continuous presence of 10 nM AP1903 (cont.). Values are the mean ± SD of duplicate points. (B) Multidose treatment of Fas-transduced T cells. LV′VFas-transduced T lymphocytes were treated once or twice (48 hours apart) without drug (open bars) or with two 2-hour pulses (doses) of 10 nM AP1903 (shaded bars). In parallel, as a control, cells were treated identically without the addition of drug (open bars). Survival was assayed 48 hours after drug treatment. Values are the mean ± SD of 2 independent experiments.