Fig. 5

MSC-EVs inhibit influenza virus-induced apoptosis. a Swine/MN/08; H1N1 (SwIV; MOI = 1) was incubated with Dulbecco’s modified Eagle’s medium (DMEM) or 10 μg/ml MSC extracellular vesicles (EVs) for 20 min at room temperature. After the incubation, pig lung epithelial cells were incubated for 1 h with SwIV or SwIV pre-incubated with MSC-EVs. At 24 h after infection, apoptotic cells were detected by TUNEL assay using the ApopTag Fluorescein Apoptosis Detection Kit (EMD Millipore). b TUNEL-positive cells in SwIV-infected and MSC-EV-treated LECs were counted at 24 h after infection. Values are expressed as mean ± SD of apoptotic cells in five microscopic fields (20×). *P < 0.05