Effect of Stat5b-CA TG expression on Treg phenotype homeostasis and suppressor function. (A) Flow cytometric analysis of fresh WT and Stat5b-CA TG LN CD4⁺FoxP3⁺ T cells incubated with monoclonal antibody specific for the indicated Ag; representative data from 1 of 2 mice per group are shown. The percentage donor CD4⁺CD45.2⁺ expressing T cells in the spleen (B) and small intestine (C) isolated from lethally irradiated B10.BR recipients injected with 10⁷ BM and 10⁶ WT CD45.1⁺CD4⁺CD25⁻ T cells together with WT or Stat5b-CA TG CD45.2⁺CD4⁺CD25⁺ Tregs on day 10 after transplantation. (D) Expression of IFN-γ and TNF-α in CD45.1⁺CD4⁺ T cells isolated from the small intestine of lethally irradiated B10.BR recipients injected with 10⁷ BM and 10⁶ WT CD45.1⁺CD4⁺CD25⁻ T cells with or without WT or Stat5b-CA TG CD45.2⁺CD4⁺CD25⁺ Tregs on day 10 after transplantation. (B-D) P values are as indicated. Data are from 1 experiment with 4 to 6 mice/group.