Fig. 2
uMSC-EVs alleviated BLM-induced pulmonary fibrosis. Mice were intratracheally instilled with a single dose of BLM (3 U/kg), and then each mouse was randomly allocated to receive either uMSC (1 × 106) or uMSC-EVs (20 μg) in 100 μL of PBS or equal volumes of PBS alone via intravenous injection on days 7 and 21; normal mice were served as control. a Schematic of the experimental design. b, c Survival rate and change of body weight after BLM treatment. d H&E and Masson staining was subjected for lung tissue sections. Scale bar = 100 μm. e Ashcroft score of histological images was determined by pathologists blind to the study design. f HYP content of lung tissue. Mean ± SEM; *p < 0.05, **p < 0.01, ***p < 0.001; n = 5. BLM, bleomycin; control (CTRL); H&E, hematoxylin and eosin; HYP, hydroxyproline