Fig. 2 |. In vitro ROS-trigged exosome release and biocompatibility of EES.
a, Schematic illustration of ROS-responsive EES. Upon exposure to H2O2, the aryl boronic ester group is oxidized and subsequently hydrolyzed to unmask a phenol group. b, Accumulative release of MSC-XOs from EES in PBS with or without H2O2 (100 μM or 1 mM). n=3. c, Size distribution of MSC-XOs released from EES determined by NanoSight. n=5. d, Representative SEM images of EES after release studies. Top image: EES in PBS; bottom image: EES in 100 μM H2O2. Scale bar, 20 μm. e, MSC-XOs (DiD-labeled) release and uptake by HUVECs (at 4 h and 12 h). Scale bar, 100 μm. n=5. f-g, Representative fluorescent images and SEM images of BMS and EES after incubation with platelet-rich plasma (f) and activated monocytes (g). Adhered platelets and U937 monocytes were pointed by red arrows. h, Quantification of adherent platelets and monocytes. n=5. P values are shown on the graph. Student’s two-tailed independent t-test was used to determine differences between two groups.