Figure 3.

Normal interleukin-2 (IL-2) signalling and phosphorylated signal transducer and activator of transcription 5 (pSTAT5) activation in cultures stimulated with T helper instructive cytokines. (a) Cell-free supernatants were collected 48 hr after CD4⁺ T cells were plated in the indicated culture conditions. Interleukin-2 production was tested using enzyme-linked immunosorbent assay. Data are represented as mean ± SD of two independent replicates. Results are representative of at least two independent experiments. (b) CD4⁺ T cells were cultured in the indicated conditions ± 100 U/ml hIL-2 for 3 days. After 3 days, cells were collected, washed and intracellularly stained for Foxp3 expression. Data are represented as mean ± SD of two replicate samples. Results are representative of two independent experiments. (c) CD4⁺ T cells were cultured in the indicated conditions for 72 hr and stained with anti-CD25 and anti-Foxp3 for analysis by flow cytometry. Numbers represent percentage of cells present in the upper left and upper right quadrant. Results are representative of two independent experiments. (d) CD4⁺ T cells cultured in the indicated conditions for 4, 24 or 48 hr were collected for intracellular staining with anti-pSTAT5 and anti-Foxp3. Numbers represent the percentage of total pSTAT5⁺ cells. Results are representative of two to three independent experiments.