Induction of FOXP3 in CD45RA⁺ cells activated with dendritic cells required TGFβ but was insufficient to suppress IL-2 production. (A) Flow cytometric analyses of FOXP3 with 259D on day 5-activated CD45RA⁺ cells stimulated with allogeneic monocyte-derived immature dendritic cells (iDC), mature dendritic cells (mDC), or CD3-depleted PBMC (APC) in the presence or absence of TGFβ1. The iDC and mDC were characterized based on their expression of CD86 and CD83. (B) Flow cytometric analyses of FOXP3, IFNγ, and IL-2 on day 7 TGFβ-treated CD45RA⁺ cells activated with iDC or mDC restimulated with PMA and ionomycin. Data are representative of 3 independent experiments. Numbers in each quadrant as in Figure 1.