Induction of Foxp3 expression is TGF-β dependent. (A-B) CD4⁺ T cells were stimulated with anti-CD3/CD28/CD2 beads and cocultured in the absence or presence of CD14⁺HLA-DR⁺ and CD14⁺HLA-DR^−/low cells. Anti–TGF-β was added at different concentrations as indicated. The expression of Foxp3 and IL-17 was performed by ICS on day 3 gating on CD4⁺ T cells. Shown are representative dot plots for 4 independent experiments (A) or results for single donors were plotted as bars gating on CD4⁺ T cells (B; *P < .05). Numbers represent percentages of events within the respective quadrants.