Figure 5. Young MSC-EVs diminished macrophage recruitment in vivo. Mice were divided into 4 groups: control, LPS, LPS + young MSC-EVs (100 μg), LPS + aging MSCs-EVs (100 μg). (A) Total cells in the BAL were harvested at 24 h and 48 h after LPS treatment. Total macrophages were quantitated by percentage of F4/80+ macrophages multiplying by total cells in BAL. (B) Dot plots represent gating strategy to stain macrophage subpopulations from BAL of LPS-treated mice. Macrophages were identified as F4/80+. Recruited macrophages were defined as F4/80+Siglec F-CD11b+. (C) Percentage of recruited macrophages in BAL at 24 h was analyzed via flow cytometry. Data are presented as mean ± SEM, n = 8–12. *p < 0.05, **p < 0.01, *** p < 0.001.