Fig. 4.

Absence of Ahr in BMDC inhibited Treg development and facilitated Th17 cell generation from naive T cells. WT and Ahr^−/− BMDC were stimulated with LPS or CpG for 24 h. MACS-sorted naive T cells from WT mice were then cocultured with or without stimulated BMDC for 4 d. Synthetic L-Kyn (50 μM) was added to some samples as indicated. (A) After 4 d coculture, Foxp3 expression in T cells was examined using FITC-conjugated anti-mouse Foxp3 antibodies and stained cells were analyzed using FACS. (B) After 4 d coculture, T cells were stimulated with PMA/ionomycin for 5 h; GolgiStop was added for the final 2 h. T cells were then intracellularly stained for IL-17 and IFN-γ and analyzed using FACS. Data are shown as dot blots. (C) Levels of IL-17 in coculture supernatants of LPS- or CpG-stimulated WT and Ahr^−/− BMDC with naive T cells after 4 d. Supernatants were harvested from BMDC–T-cell coculture after 4 d. IL-17 was measured in coculture supernatants using ELISA. These results are representative of three independent experiments.