FIG 6.

CD69 expression rescues iTreg cell differentiation in the absence of the IL-2Rγc/Foxp3 signaling pathway. (A) Naive CD4⁺ T cells from Foxp3-mRFP/cd69^+/+ or Foxp3-mRFP/cd69^−/− littermates were cultured for 72 h under Treg-skewed conditions and treated with a chemical Jak3 inhibitor or an equal concentration of dimethyl sulfoxide (DMSO) for the last 9 h. The percentages of phospho-STAT5⁺ cells and the levels of STAT5 phosphorylation determined by FACS analysis and compared to an isotype Ab are shown. (B) Quantification of reporter Foxp3-mRFP⁺ cells treated as described above for panel A. (C) Naive CD4⁺ T cells from Il2rγ^−/−/cd69^−/− and Il2rγ^−/− mice were cultured as described above for panel A, and the percentages of phospho-STAT5⁺ cells and the levels of STAT5 phosphorylation were determined by FACS analysis. (D) Quantification of CD25⁺ Treg cells by FACS analysis. Data are from two independent experiments (n = 3 for each genotype). Error bars show standard deviations. Data were evaluated by ANOVA followed by Bonferroni's multiple-comparison test. *, P < 0.05; **, P < 0.01; ***, P < 0.001.