Fig. 4

Type I IFNs regulates lung myeloid cell recruitment during M. bovis infection. Mice treated with αIFNAR1 antibody or isotype antibody followed by infection with M. bovis. Myeloid cell populations in infected lung tissues were analyzed by flow cytometry at 21 days p.i. a Lung cells were gated on single live cells using forward and side scatter parameters. Gating strategy for quantification of myeloid cell populations is shown. R1 (CD11b^lo CD11c⁺): alveolar macrophages; R2 (CD11b^hi CD11c⁺): myeloid dendritic cells (DCs); gating on R3 (CD11b^hi CD11c^neg), R4 (CD11b^hi CD11c^neg Ly6C^lo/neg): recruited macrophages; R5 (CD11b^hi CD11c^neg Ly6C^int/hi Ly6G^neg): monocytes; and R6 (CD11b^hi CD11c^neg Ly6C^int Ly6G^hi): neutrophils. b-f Quantification of myeloid cells phenotypes. Each bar represents mean ± SD (n = 5). Data are a pool of two independent experiments. g H&E staining of lung sections were performed to measure neutrophils infiltration (scale bar: 10 μm). Arrows: neutrophils. h The number of neutrophils infiltrating the lungs of αIFNAR1 mice was evaluated at 21 days p.i. (I) Expression of MHC class II on myeloid DCs in the lungs of mice at 21 days p.i. Data are expressed as MFI ± SE (n = 3). j-l Expression of costimulatory molecules, (j) CD40, (k) CD80, and (l) CD86 on myeloid DCs in the lungs of mice at 21 days p.i; Data are expressed as MFI ± SE (n = 3). (* P < 0.05; ** P < 0.01)