Bhlhe40 suppresses Chlamydia-specific Tr1 differentiation in a T cell-intrinsic manner.

(A-C) WT and Bhlhe40^-/- mice were infected intravaginally with 1×10⁵ C. muridarum and analyzed at 10 dpi. (A) Representative FACS plots depicting IFNγ- and IL-10-producing CD4 T cells (gated on live CD90.2⁺CD4⁺CD44^hi cells). (B) Percentages and total cell numbers of IFNγ⁺, IL-10⁺ and IFNγ⁺IL-10⁺ CD4 T cells within the CD4⁺CD44^hi population. (C) Mean fluorescence intensities (MFIs) of IFNγ and IL-10 in CD4⁺CD44^hiIFNγ⁺ and CD4⁺CD44^hiIL-10⁺ T cells, respectively. Data are from two independent experiments with 8 mice per group. Each data point represents an individual mouse. (D-H) Mixed WT and Bhlhe40^-/- CD4 T cell adoptive transfer. (D) Experimental workflow. (E) Normalized ratios of Bhlhe40^-/- (CD45.2⁺) and WT (CD45.1⁺) donor CD4 T cells in TCRβ^-/- host. Representative FACS plots (F), summary data (G) and MFI (H) of cytokine-producing donor CD4 T cells in TCRβ^-/- FRT. Data are from two independent experiments with 6 mice per group. Each pair of data points represents the two donor T cell populations in an individual TCRβ^-/- host. (I-K) Chlamydia-specific TP1 CD4 T cell adoptive transfer. (I) Experimental workflow. Representative FACS plots (J) and summary data (K) of cytokine-producing Bhlhe40^-/- TP1 (CD45.2⁺CD90.1^-), WT TP1 (CD45.2⁺CD90.1⁺) and B6 host (CD45.2^-CD90.1^-) CD4 T cells in the host FRT. Data are from two independent experiments with 6 samples per group. Each data point represents a pooled FRT sample from 4 mice. Error bars represent the mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, ns, not significant by unpaired t test in (B-C), and paired t test in (E-K).