Fig. 5.

sEV uptake by iHCECs. (A) Schematic illustration on experimental procedures of labeling sEVs by lipophilic fluorescent dye PKH26. The sEVs are isolated from both SEED-treated (SEED) and untreated (Control) BM-MSCs, while the 4-fold diluted sEV sample from the SEED group is regarded as Dilution group. To eliminate background noise, PKH26 solution with identical dye concentration is processed by the same experimental procedure to set the basal level of residual PKH26 molecules (Background). (B) Fluorescence images on iHCECs (scale bars: 20 ​μm). SEED (first column), Control (second column), Dilution (third column), and Background (fourth column) represent that iHCECs are co-incubated with the corresponding labeling samples for 14 ​h, respectively. (C, D) Fluorescent intensity (F.I.) per cell of (C) nucleus and (D) PKH26 quantified from (B), normalized by the intensity of Control group. All error bars represent mean ​± ​standard error of the mean (N ​= ​3, ∗∗P ​< ​0.01, NS represents no statistical significance).