Fig. 6.

Tregs primed by IDO⁺pDCs are suppressive in vivo and control EAE development. (A, B) CD4⁺CD25^hi cells were purified from dLNs of WT → WT, pIII + IV^−/− → WT and IDO^−/− → WT BM chimeras 10 days after EAE induction, and transferred (arrow) into WT recipients further immunized for EAE the day after. (A) Experimental design is represented. Foxp3 expression in sorted cells. (B) Clinical scores were followed daily in control mice (⊡) and in mice transferred with WT Treg (■), IDO^−/− Tregs () or pIII + IV^−/− Tregs (○) (two-way ANOVA with Bonferroni post Hoc test). (A, B) Results are representative of at least 2 independent experiments. Error bars depict mean ± SEM. *P < 0.05, **P < 0.01. See also Table 1. (C, D) CD4⁺CD25^hi cells were purified from total skin LNs of naïve WT → WT and IDO^−/− → WT BM chimeras or from dLNs of WT → WT and IDO^−/− → WT BM chimeras 10 days after EAE induction. (C) CD4⁺CD25^hi cells were with proliferation dye-labeled 2D2 CD4⁺ T cells and LPS activated, MOG_35–55 loaded, cDCs. 2D2 T cell proliferation was assessed after 5 days. Flow cytometry histograms represent 2D2 T cell proliferation for indicated conditions. Histograms represent the percentages of Treg-mediated suppression (two-tailed Mann-Whitney test). Results are representative of 2 independent experiments. Error bars depict mean ± SEM. **P < 0.01, NS = Non significant. (D) CD4⁺CD25^hi cells were transferred into WT recipients further immunized for EAE the day after. Clinical scores and incidence (d15) are depicted. Data are representative of 2 experiments. Error bars represent mean ± SEM. One-way ANOVA with Bonferroni post Hoc test was used. *P < 0.05.