Gamma chain cytokines maintain CD25 and Foxp3 expression in T
cells. Histograms of CD25 expression (a) or Foxp3 (b), of live Tcon or Treg cells from WT (two upper panels) or Bim-/- (two lower panels) mice stimulated for 3 days with soluble anti-CD3 and anti-CD28. Cytokines were added at indicated 20 ng/ml concentrations in cultures at the beginning of stimulation. Gates show CD25high (a) or Foxp3high (b) cells.