Extended Data Fig. 6: B cell expression of IFNγ receptor, but not T-bet, is necessary for maximal PB response during Salmonella infection.
a-d, Additional data described in Fig. 5a, data combined from two experiments, n = 11 HK B-WT, n = 12 Inf B-WT, n = 13 HK B-KO and Inf B-KO. a, NP-specific IgG1 and IgG2b antibody forming cells (AFC), and the sum of IgM+IgG1 + IgG2b + IgG2c. Symbols represent individual mice and bars the mean +/−SD, P values calculated by two-tailed t-tests. b, Example gating for IFNγ producing T and B cells (summarized in Fig. 5c). For CD4 + T cells, examples are shown from both infected and HK control mice as different gates for CD44+ cells were necessary. c, Example upstream gating for intracellular IFNgR stain, CD19+ and/or CD138+ gate represents B cells + PB, which is then separated in to ‘PB’ or CD138- cells, and then ‘GC’ and the remainder are called ‘non-GC/PB’ which represents a majority naïve cells. d, Histograms showing selection of Cre-escape cells among PB populations from B-KO mice (filled histograms). e, Additional ELISPOT data as described in Fig. 5e. Data combined from 2 experiments, n = 14 (HK B-WT, HK B-KO, Inf B-WT), n = 16 Inf B-KO, symbols represent individual mice and bars the mean +/- SD, all P values calculated by two-tailed t-test. f, Histograms showing T-bet expression among cells gated as in panel (c) with CD19+ and/or CD138+ gate. g, Splenocytes from mice treated for 3 days with recombinant IL-12 in vivo (Fig. 2c), were stained for T-bet expression in B cells. A population of T-bet+ IRF4- cells was found to be expanded in IL-12 treated mice. This population (orange) was overlayed on all B cells (gray) to show their CD38 CD95 staining in relation to CD38low CD95hi early GC B cells. FACS plots are representative of n = 10 mice per group. h, Proliferation index of in vitro cultured CD19-Cre+/− T-bet flox B cells from Fig. 5i, n = 3 biological replicates; symbols are mean +/- SD, analyzed by two-way ANOVA. One of two independent experiments with similar results is shown. i, Representative FACS plots of T-bet staining among CD19-Cre+/− T-bet flox B cells in indicated conditions from Fig. 5i. For all charts (a, e, h), NS = not significant, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.
