Fig. 5

Therapeutic effects of EPC exosomes on LPS-induced acute lung injury by histological analysis and myeloperoxidase (MPO) activity. Lung (a) sections were stained with H&E and examined histologically at 48 h after LPS instillation. The representative sections are shown at × 400 original magnification, and scale bars are 20 mm. The PBS group showed normal lung tissue including thin alveolar walls and few alveolar macrophages. Yellow arrows indicate neutrophils in the alveolar space, green arrows indicate neutrophils in the interstitial space, blue arrows indicates hyaline membranes, and black arrows indicate thickening of the alveolar walls. Lung injury scores (b) were assessed. *p < 0.05 compared with the PBS group; ^#p < 0.05 compared with the LPS group. n = 4 mice per group. Results are represented as mean ± SE. MPO activity (c) in the lung tissue were measured at 24 h after LPS instillation. *p < 0.05 compared with the PBS group; ^#p < 0.05 compared with the LPS group. n = 3–6 mice per group. Results are represented as mean ± SE