Fig. 5. TLR2 expression by both hematopoietic and non-hematopoietic lineages contribute to early innate immune responses to mucosal vaccination with Pam₂Cys Spike.

a Experimental outline. Tlr2−/− (KO) or wild type (WT) mice (n = 6) were irradiated then received transfer of Tlr2−/− or WT bone marrow (BM) cells intravenously (i.v). Mice were rested for 12 weeks to allow hematopoietic reconstitution and replacement, then immunized once with Pam₂Cys Spike i.n. Immune cells in the lungs were characterized at 24 h post vaccination. b To verify bone marrow replacement, unsupervised clustering of lung CD45⁺ cells was performed on flow cytometry data and relative expression of TLR2 was examined by FIt-SNE for each experimental group. c Mean proportions of CD45⁺ cell populations in the lungs were determined by flow cytometry, with (d) quantitation of populations of interest (KO host KO BM, black; KO host WT BM, red; WT host KO BM, blue; WT host WT BM, purple). Data are for individual mice (n = 6). Box and whiskers plots show median (centre), 25th and 75th percentile (box), lowest and highest value (whiskers). Statistics: p-values indicated, Kruskal–Wallis test, Dunn’s multiple comparisons. Source data are provided as a Source Data file.