Figure 3.
RT and IAV alter lung macrophage population size and phenotype. CD45+ immune cells isolated from lung digests, collected 26 week following exposure to RT and IAV, either alone or in combination, or from non-exposed control mice, were analyzed by flow cytometry. Early IAV was administered 1 week after RT, whereas late IAV was administered 20 weeks after RT. A) Following the exclusion of doublets, dead cells, and Ly6G+ cells, macrophages were identified by the positive expression of CD45, F4/80, and, for TR-AMs, autofluorescence. Distinct lung macrophage subsets were identified as tissue-resident alveolar macrophages (TR-AMs; CD11blow, CD11c+), monocyte-derived alveolar macrophages (Mo-AMs; CD11b+, CD11c+), and monocyte-derived macrophages (Mo-MPs; CD11b+, CD11c-). B) Proportions of TR-AMs, Mo-AMs, and Mo-MPs within the total macrophage population. C) Percentages of TR-AMs, Mo-AMs, and Mo-MPs in each experimental condition. D) Percentages of CD206+ cells within TR-AMs, Mo-AMs, and Mo-MPs. E) Percentages of Ly6C+ cells within Mo-AMs and Mo-MPs. Bars represent mean ± SEM. Symbols (circles) represent each mouse. n=4 mice per condition. Significantly different comparisons are as indicated by brackets. *P<0.05, **P<0.01, ***P<0.001, ****P<0.0001.