Inverse relationship between Foxp3 and Th17 in TLo, but not THi, conditions. (A) Human CD4⁺ T cells were cultured under THi or TLo conditions for 6 days. Expression of IL-17 and Foxp3 was determined by intracellular flow cytometry. Plots are representative of 4 independent experiments. (B) Human CD4⁺ T cells were cultured under THi or TLo conditions for 3, 6, or 10 days. To generate day 10 cells, beads were removed at day 6 and cells were washed, replated, and cultured for 4 more days. Expression of IL-17 and Foxp3 were determined by intracellular flow cytometry (n = 3). IL-17 data shown in Figure 3D were plotted in this graph. (C) IPEX patient PBMCs were cultured under THi or TLo conditions. Expression of IL-17 and IFN-γ were determined by intracellular flow cytometry.