Figure 2. Characterization and uptake of BMSC exosomes. (A) Transmission electron microscopy (TEM) showed that BMSC-derived exosomes had a typical cup-like morphology. Scale bar: 50 nm. (B) Nanosight Tracking Analysis (NTA) detection revealed that the average vesicle diameter was about 140 nm. (C) Western blot analysis of exosome lysates revealed positive expression of the exosome surface markers, CD63, CD81 and CD9. No cerulein was detected in BMSC-derived exosomes. (D) Detection of exosome uptake by BMSCs. Dil : red, DAPI: blue. Scale bar: 20 μm.