Figure 1.

Isolation and characterization of umbilical cord mesenchymal stem cells (UCMSCs)-derived exosomes (U-exo). UCMSCs were cultured in medium containing exosome-depleted FBS for 48 h and culture supernatant was collected and centrifuged at 300 × g for 10 min to remove cellular debris and 0.22 μm filtration using syringe was used to discard small particles including apoptotic bodies. Subsequently, conditioned medium (CM) was collected and exosome was isolated using Exo-spin precipitation and size exclusion chromatography purification method. (A) Nanoparticle tracking analysis of exosomes isolated and purified from UCMSCs. The mean diameter of the isolated exosomes was measured to be under 150 nm, indicative of the majority of extracellular vesicles (EVs) being exosomes. (B) Transmission electron microscopy of U-exo at 70,000x magnification. Scale bar =200 nm (C) Immunoblot analysis of U-exo markers (Alix, TSG101, CD9, and CD63) is shown. Calnexin (Endoplasmic reticulum marker) was used as a negative control. WCL: whole cell lysates; Exo: U-exo.