Effect of Stat5b overexpression on CD4 T-cell function in a GVHD model. (A) CD25 and FoxP3 expression of pooled CD4⁺ T cells purified from LNs of WT (left) and Stat5b-CA TG (right) mice, used for the experiment shown in panel B. (B) Survival and weights of lethally irradiated B10.BR recipients injected with 10⁷ BM (*) and 1 × 10⁶ (▼, ▽) or 3 × 10⁶ (♦, ◇) CD4⁺ T cells isolated from WT (▼, ♦) or Stat5b-CA TG (▽, ◇) mice. P = .003, ▼ vs ▽. P < .001, ♦ vs ◇. (C) Values are for one experiment; n = 8 mice/group. CD25 and FoxP3 expression of CD4⁺CD25⁺ T cells purified from pooled LNs of WT (left) and Stat5b-CA TG (right) mice, used for the experiment shown in panel D. (D) Survival and weights of lethally irradiated bm12 recipient injected with 10⁷ BM (*) and 2 × 10⁶ B6 CD4⁺CD25⁻ T cells alone (▼) or along with 2 × 10⁶ CD4⁺CD25⁺ Tregs isolated from WT (♦) or Stat5b-CA TG (◇) mice. P = .001, ♦ vs ◇. P < .001, ▼ vs ♦ and ◇. Pooled data are from 2 experiments; n = 16 mice/group total. (E) CD25 and FoxP3 expression of purified CD4⁺CD25⁺ T cells isolated from pooled LNs of WT (left) and Stat5b-CA TG (right) mice, used for experiment shown in panel F. (F) Survival and weights of lethally irradiated B10.BR recipients injected with 10⁷ BM (*) and 1.5 × 10⁶ B6 CD4⁺CD25⁻ T cells alone (▼) or along with 1.125 × 10⁶ CD4⁺CD25⁺ Tregs isolated from WT (♦) or Stat5b-CA TG (◇) mice. P = .003, ♦ vs ◇. P = .02, ▼ vs ♦. P < .001, ▼ vs ◇. Pooled data are from 2 experiments; n = 16 mice/group total. (G) Survival and weights of lethally irradiated B10.BR recipients injected with 10⁷ BM (*) and 1.5 × 10⁶ B6 CD4⁺CD25⁻ T cells alone (▼) or along with 0.375 × 10⁶ CD4⁺CD25⁺ Tregs isolated from Stat5b-CA TG (◇) mice. P = not significant, ▼ vs ◇. Pooled data are from 2 experiments; n = 16 mice/group total.