Figure 1. Muscularis macrophages demonstrate a shift from anti-inflammatory to proinflammatory state with aging.
On flow cytometry, MMs (CD45+F4/80+ cells) were found to be the predominant immune cell in the muscularis layer, comprising between 15–20% of all live cells, but their numbers did not differ significantly with age (A). MMs sorted from old and mid-aged mice revealed a decline in expression of M2 markers CD206, FIZZ1 and TGFβ (B), and a rise in expression of M1 markers, particularly IL-6, which reached statistical significance in old (C) compared to young mice by qRT-PCR. n≥10 for all groups, *p<.05, ***p<.001 by one-way ANOVA with Bonferroni’s multiple comparisons test.
