CD8⁺ DCs inhibit the allostimulatory capacity of DCs from CTX-treated mice in vitro. CD11c⁺ DCs from CTX-treated or naive mice were magnetically sorted from LNs. CD8⁺ and CD8⁻ DCs of naive mice were also magnetically or FACS sorted from the spleen. DCs (naive DC indicates DCs from naive mice; CTX DCs, DCs from CTX-treated mice; CD8⁺, CD8⁺ DCs; and CD8⁻, CD8⁻ DCs) were cocultured with the combinations indicated with CFSE-labeled CD3⁺ T cells from allogeneic Balb/c mice for 4 days. (A) CD4⁺ and CD8⁺ T-cell proliferation was examined by measurement of CFSE dilution and the T-cell activation marker, CD44. To assess IFN-γ production, T cells were stimulated with phorbol myristate acetate and ionomycin for 6 hours; brefeldin A was present during the last 5 hours, and then stained for intracellular IFN-γ. Results are the mean ± SEM of triplicate wells. Data are representative of 3 experiments. (B) The proportion, proliferation, and IFN-γ secretion of CD4⁺ Foxp3⁺Tregs were also examined. Results are the mean ± SEM of triplicate wells. Data are representative of 3 experiments. *Statistically significant.