FIGURE 7.

PRMT5 is important for maintaining IL-7 and IL-2 signaling in T cells. (A,C) Naïve CD8⁺ and CD4⁺ T cells were purified from control and CD4^Cre PRMT5^fl/fl mice and stimulated for the indicated times with anti-CD3 and anti-CD28-coated beads in the presence of IL-2 or anti-IL-2 blocking antibody, and analyzed by flow cytometry for the expression of Nur77, CD69, CD25, γc, and pSTAT5. Representative histograms and plots are shown from at least two independent experiments. (B) Naïve CD4⁺ T cells were purified from control and CD4^Cre PRMT5^fl/fl mice and stimulated for the indicated times with biotinylated anti-CD3, anti-CD4, and anti-CD28 plus streptavidin. The phosphorylation of ERK1/2 was analyzed by Western blot. Total PLCγ1 was used as a loading control. The data are representative of two independent experiments. (D) Naïve CD8⁺ and CD4⁺ T cells were purified from control and CD4^Cre PRMT5^fl/fl mice and left unstimulated or stimulated for 30 min with IL-7, followed by flow cytometric analysis of pSTAT5 expression. The frequency of pSTAT5⁺ cells among IL-7-stimulated T cells of control and CD4^Cre PRMT5^fl/fl mice (n = 4) from two independent experiments is plotted as mean ± SEM. **P < 0.01 by unpaired two-tailed Student’s t-test. (E,F) T cell subsets from the thymus and spleen of control and CD4^Cre PRMT5^fl/fl mice were analyzed for expression of CD25, CD122, CD127, and γc by flow cytometry. Gating strategy is shown in Figures 1A,D and Supplementary Figure S3C. Representative histograms are shown from three independent experiments.