Fig. 1: Endogenous MAIT cells do not contribute to host protection following Mtb infection.

Wild-type (WT) C57BL/6 mice were infected with ~150 CFU of Mtb by aerosol and lungs were harvested at the indicated time points. a Representative FACS plots of MR1/5-OP-RU and I-A^b/ESAT-6_4-17 tetramer staining of lung cells. b Kinetics of the frequency of MAIT cells and I-A^b/ESAT-6_4-17⁺ CD4 T cells among TCRβ⁺ cells in the lungs. Bacterial CFU in the lungs are also shown. c Number of total lung cells, MAIT cells and I-A^b/ESAT-6_4-17⁺ CD4 T cells over time. d Representative histogram plots of PD-1, CTLA4, or Ki-67 expression by lung MAIT cells at the indicated time points. Numbers indicate the geometric MFI (PD-1) or % positive (CTLA4 and Ki-67) in the gated MAIT cells. e Representative FACS plots and histograms of CD45 intravascular (i.v.) staining of lung MAIT cells. f Kinetics of the frequency of CD45 i.v. staining negative (CD45 i.v.⁻) MAIT cells in the lungs. g Representative FACS plots of cytokine production by lung MAIT cells after stimulation with PMA and ionomycin. h Kinetics of the frequency of IL-17A-, TNF-, and IFN-γ-producing MAIT cells in the lungs. i Survival curve of WT and MR1^−/− mice (n = 5 per group) after aerosol Mtb infection. Date are representative of at least two experiments with three or more mice per time point or group. Error bars represent mean ± SEM.