The delivery of AdMSC-Exos alleviates lung inflammation and injury in mice. C57BL/6 mice (n = 5 mice/group) were challenged with LPS (1 mg/kg, intratracheally) for 4 h, and then tail vein injected with PBS or Exos (10 μg/mL). 24 h later, mice were sacrificed and subjected to the functional analysis. (A) Representative H&E staining of lung tissues (Scale bar, 50 μm). The histogram shows the lung tissue pathological damage score. (B) BALF cell counts; (C) MPO level in lungs; (D) total protein level; and (E) cytokine concentration in the BAL fluid. (F) Flow cytometry analysis of Alveolar macrophages (CD11c+ Siglec F+) in BAL fluid (Gate on CD11b- CD64+). (G) Flow cytometry analysis of macrophages (CD11b+ F4/80+) in BAL fluid. (H) Flow cytometry analysis of neutrophils (CD11b+ Ly6G+) in BAL fluid. (I) Survival rate of the mice that were challenged with LPS at a high dose (10 mg/kg, i.t.) and then treated with Exos or PBS (Injection via tail vein). Kaplan-Meier survival plots were depicted (n = 15 mice/group). All the data are expressed as the mean ± SD; *P < 0.05, **P < 0.01, ***P < 0.001.