Figure 8.

IFN-γ as a candidate downstream target of T-bet in regulating TFH cell expansion. (A) Flow cytometry of IFN-γ production in TFH cells (left), with the summary of IFN-γ percentages (right) derived from WT and Tbx21^−/− mice at day 8 post LCMV infection. (B) Flow cytometry of IFN-γ production in WT and Tbx21^−/− TFH cells (left), with the summary of IFN-γ percentages (right) derived from same bone marrow chimera mice at day 8 post LCMV infection. (C,D) WT, Tbx21^−/− and Ifng^−/− mice were infected with LCMV. Spleens were harvested at day 8 post infection. (C) Flow cytometry of TFH cells (left) with the summary of percentages and numbers (right) in these mice. (D) Flow cytometry of T-bet expression (left), and the summary of T-bet expression (showed as MFI) in TFH cells of WT, Tbx21^−/−, and Ifng^−/− mice. Numbers adjacent to outlined areas in (A–C) indicate percent of each cell subset in parent subset. ns, not significant; ^*P < 0.05, ^**P < 0.01, ^***P < 0.001, ^****P < 0.0001 (unpaired two-tailed t-test). Data are representative of two independent experiments with 3–5 mice per group (error bars, SEM).