In contrast, the number of alveolar macrophages (MHC-II+Ly6G-Ly6C-CD11blowCD11c+) and monocyte-derived alveolar macrophages (MDMs) (MerTK+ CD11c+ CD11b- MHC-II+ CCR2+) decreased in infected mice compared to non-infected ones (p<0.05, between the numbers at any time point post infection versus the non-infected mice; one-way ANOVA) (Fig 1B). Here, CCR2 is linked to infection.