FIGURE 3.

Kinetics of transcription factor expression in activated naive and memory CD4⁺ T cells. Naive and memory CD4⁺ T cells were stimulated with immobilized anti-CD3 (1 μg/ml) and anti-CD28 (1 μg/ml) for 0 to 72 h. The kinetics of transcription factor expression in activated cells were analyzed by FACS (a). By intracellular staining analysis, at early time of stimulation (before 6 h), there was significantly higher T-bet expression in memory CD4⁺ T cells compared with naive CD4⁺ T cells, but the expression of pSTAT-1 and pSTAT-4 (b) was not significantly different between activated naive and memory CD4⁺ T cells. BFA was added 6 h before cells were harvested at different time points, and IFN-γ and T-bet were detected by FACS (c). Statistical data shown are for the results from three independent experiments.