Fig. 4: Monocyte recruitment to the brain is not required to mount an inflammatory response.

a–g Mice were subjected to photothrombotic (PT) stroke or sham control for 3 or 24 h, perfused brains were dissociated, and cells were stained for analysis by spectral flow cytometry. Single, viable cells (also see Fig. S2) were used to identify monocyte-derived macrophages (mono-mac; CD45^hiCD11b⁺Ly6G⁻F4/80^midLy6C⁺). Mean fluorescence intensity of a CD206, b CD80 c CD86, d MHC-II, e Arg1, f EGR2 and g iNOS are displayed as fold-change versus sham control of the same region (IL—Ipsilateral, CL—contralateral; sham n = 4, PT n = 6). h–n C57BL/6 (WT—wild type) or Ccr2^rfp/rfp (Ccr2^−/−) mice were subjected to a PT stroke 24 h. h Deficiency of functional mouse CCR2 in Ccr2^rpf/rfp mice. Image created with BioRender.com. Perfused brains were dissociated, and cell populations were analyzed by flow cytometry for i microglia (CD45^midCD11b⁺Ly6G⁻F4/80^hiLy6C⁻), j neutrophils (CD45^hiCD11b⁺Ly6G⁺), k monocytes (CD45^hiCD11b⁺Ly6G⁻F4/80^loLy6C⁺) and l monocyte-derived macrophages (CD45^hiCD11b⁺Ly6G⁻F4/80^midLy6C⁺). m Perfused brains were homogenized, and the supernatant was analyzed using a LEGENDplex cytokine panel. Analytes taken from infarct core homogenate were assessed and compared to contralateral (CL) tissue, presented as log₂ fold-change (C57BL/6 n = 6, ccr2^−/− n = 8). n Time mice were able to remain on a suspended wire. Dotted line represents mean sham hang time (n = 6). A one-way ANOVA was used for analysis of multiple groups, and a Mann–Whitney test was performed when analyzing the wire hang test. *p  <  0.05, **p  <  0.01, ***p  <  0.001, ****p  <  0.0001, ns no significance.