Fig. 5

High diversity of infiltrating immune cells in brains of IRF7-deficient mice upon LGTV infection. WT and Irf7^−/− mice were infected intraperitoneally with 10⁴ FFU LGTV (n = 6) and immune cells were isolated from brains for flow cytometric characterization. A representative gating strategy (A-K). FSC and SSC gating of immune cells (A). Life cell selection (B) and separation from doublets (C). Neutrophil granulocytes Ly6G + CD11b + (D), differentiation of remaining mononuclear cells by CD45 and CD11b expression (E). Identification of NK1.1⁺ and NK1.1⁻CD3⁺ cells within CD45⁺CD11b⁻ population (F). NK1.1⁻CD3⁺ cells were gated for CD4 and CD8 (G). Remaining NK1.1⁻CD3⁻ cells from (F) were separated in B220⁺CD11c⁻ B cells (H). B220⁺CD11c⁺ cells (H) which were further assessed for MHC class II (MHCII) and Ly6C expression show plasmacytoid dendritic cells (pDCs) (I). CD45⁺CD11b⁺ cells from (E) were gated for CD45 and CD206 separating brain-resident microglia from border-associated macrophages (BAMs) and infiltrating myeloid cells (J). MHCII and CD11c expression of myeloid cells to distinguish conventional dendritic cells (cDCs) and monocytes/macrophages (K). Monocytes and macrophages characterization by CD11b and Ly6C expression: Ly6C^hi inflammatory monocytes, Ly6Clow macrophages (L). Clustering of Infiltrating immune Uniform Manifold Approximation and Projection for Dimension Reduction (UMAP), constructing a framework of cells while preserving the global structure of sample. Cells within clusters were subsequently identified by overlaying previously gated populations (M) and compared between groups of LGTV-infected WT and Irf7^−/− mice on day 7 post-infection (N). Stacked bar charts display the overall frequency of immune cell subsets within the brains of mice on day 0 and 7 post-infection (O)