Fig 2: UTX increases inhibitory receptor expressionWT and UTX-deficient P14+CD8+ T cells were transferred into separate mice and analyzed for their expression of inhibitory receptors at multiple times after LCMV-A22 infection.(A–D) Time course showing the percent of donor P14s expressing PD-1 (A), LAG-3 (B), TIM-3 (C), and 2B4 (D) in blood.(E) The gMFI of inhibitory receptors on donor P14s collected from blood at day 15 post-infection. The measurement was determined for donor cells that stained positive for the indicated molecule.(F) The viral titer in the liver at various days post-infection.Data show one representative experiment of three independent experiments with 2–5 mice per group. Error bars display mean ± SEM. Significance was determined using an unpaired Student’s t test (*p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001).See also Figure S4.

Fig 3: T and B GC Cells Express T-bet Following Influenza InfectionZsGreen_T-bet reporter mice were infected with influenza and dLNs analyzed.(A–C) Representative confocal micrograph at indicated days p.i. T-bet+ cells (yellow) in GC LZ (IgD-GL7+CD35+) and DZ (IgD-GL7+CD35+). Arrow indicates T-bet+GL7+ cell at d4 p.i. Dashed lines mark GC regions, bottom panels show T-bet+ cells without GC markers (A). Day 8 p.i. T-bet+ GC co-stained with CD4 (cyan) (B) and co-stained with B220 (cyan) (C).(D) Representative flow cytometry plots showing frequency of T-bet+ TFH (red, CD44+PSGL-1- Ly6c- PD-1+ CXCR5+) and T-bet+ TH1 (blue, CD44+ PSGL-1+Ly6c+) at indicated days p.i.(E and F) Frequency (E) and total numbers (F) of T-bet+ TFH and TH1 cells.(G) Flow cytometry plots showing frequency of T-bet+ GC B cells (red, B220+IgD-CD95+CD38-) and plasma cells (blue, B220lo CD138+).(H and I) Frequency (H) and total numbers (I) of T-bet+ GC B and plasma cells.In (E), (F), (H), and (I), data are pooled from three independent experiments. Data are mean ± SEM.

Fig 4: T Cell-Intrinsic T-bet Deficiency Regulates TFH Cytokine Production, While Neither T Cell- or B Cell-Intrinsic T-bet Deficiency Overtly Affects GC Structure(A–C) CD4Cre_IL-21GFP and Tbx21?T_IL-21GFP mice were infected with influenza, and dLN TFH (CD44+PSGL-1-Ly6c-PD-1+CXCR5+) cells were re-stimulated and analyzed d8 p.i. Representative flow cytometry plots (A) and frequency (B and C) of IFN? and IL-21GFP in indicated mice.(D–G) CD4cre and Tbx21?T mice were infected with influenza and dLNs analyzed at d8 p.i. Representative flow cytometry plots (D) and total number of GC B cells (B220+IgD-CD95+CD38-) (E). Plots of DZ (CXCR4+CD86-) and LZ (CXCR4-CD86+) GC B cells (F). Confocal micrographs of dLN (white, IgD+ B cell follicles; magenta, GL7+ GCs) from indicated mice (G).(H–L) CD23cre and Tbx21?B mice were infected with influenza, and dLNs were analyzed at d8 p.i. Representative flow cytometry plots (H) and total number of GC B cells (B220+IgD-CD95+CD38-) (I). (J) Plots of DZ (CXCR4+CD86-) and LZ (CXCR4-CD86+) GC B cells. Confocal micrographs of dLNs (white, IgD+ B cell follicles; magenta, GL7+ GCs) from indicated mice (K). Confocal micrographs of dLN GCs from indicated mice (blue, IgD+ B cell follicles; magenta, GL7+ GCs; white, CD35+ LZ) (L).In (A)–(F) and (H)–(J), data are representative of three independent experiments, n = 3–5 mice/group. In (G), (K), and (L), data are representative of two independent experiments, n = 3–5 mice/group. Data are mean ± SEM.

Fig 5: T Cell-Specific Tbx21 Deficiency Promotes TFH Differentiation following Influenza InfectionCD4cre and Tbx21?T mice were infected with influenza, and dLN CD4+CD44+ polyclonal and antigen-specific cells were analyzed at d8 p.i.(A–D) Representative flow cytometry plots of polyclonal CD4+CD44+ (A and C) with frequency and total number (B and D) of natural repertoire of TH1 (CD44+PSGL-1+Ly6c+) (A and B) and TFH (CD44+PSGL-1-Ly6c-PD1+CXCR5+) (C and D).(E and F) Plots (E) and frequency and total number (F) of NP311 CD4+ T cells.(G–J) Plots (G and I) and frequency and total number (H and J) of TH1 (NP311+CD44+PSGL-1+Ly6c+) (G and H) and TFH (NP311+ PSGL-1-Ly6c-PD-1+CXCR5+) (I and J).Data are representative of three independent experiments, n = 3–5 mice/group. Data are mean ± SEM.