EVs were isolated by the combination of ultrafiltration (Amicon Ultra-15 Centrifugal Filter Device, Merck) and Total Exosome Isolation Kit (Life Technologies Australia Pty Ltd.), according to manufacturers’ instructions. Briefly, conditioned culture media were centrifuged at 2000g for 30 min to further remove cells and debris. The 12 ml of resulting conditioned culture media was then transferred to an Ultra-15 50-kDa device and concentrated to 120 μl using an Allegra X-22R centrifuge at 4000g for 20 min at 4°C. The concentrate was transferred to a new tube and mixed with 60 μl of Total Exosome Isolation reagent by vortexing. The concentrate/reagent mixture was incubated overnight at 4°C and subsequently centrifuged at 10,000g for 1 hour at 4°C. The supernatants were discarded, and EVs were contained in the pellet at the bottom of the tube.