Role of B7 family members in the ability of systemic and MLN CD11c⁺ DCs to generate antigen-specific T_H17 cells from CD4⁺Foxp3^– T cells. Generation of KJ1-26⁺IL-17⁺ T cells from Sp KJ1-26⁺Foxp3^EGFP− T cells by Sp (A-B) or MLN (A,C) CD11c⁺ DCs obtained from WT mice and the B7^−/− mice in neutral conditions in the presence or absence of TGF-β1, IL-6 plus TGF-β1, or CpG ODN plus TGF-β1 was analyzed by flow cytometry. Data are represented by a dot plot, and numbers represent the proportion of IL-17⁺ cells among gated CD4⁺ T cells in each quadrant (A) and are the percentage of positive cells (B-C). *P < .01 compared with WT mice. Data are the mean ± SD, and the results are representative of 4 independent experiments.