Figure 3  Th2- or IL-4–Producing Cells Lack FOXP3
(A) FACS analysis of intracellular FOXP3 and IL-4 expression following PMA/Ionomycin stimulation. CD4+ T cells were gated on the basis of CD45RO and CD25 surface expression (upper panel), and gated cells are shown below for the CD45RO+CD25− (A, left panel), the CD45RO+CD25+ (right panel), and the CD45RO−CD25− subsets (central panel). A statistical analysis of eight independent donors after subtraction of the isotype control are shown in (B). The dotted gray line indicates the IC background level. The error bars show the error of the mean. (C) Similarly, a Th2 clone (BR8), CRTH2+ Th2 cells, IL-4-secreting cells, and memory T cells (CD45RO) were stained for FOXP3 and IL-4. Data are representative of three independent experiments.