Fig. 4

Isolated EVs contain latent enzyme. After isolating at pelleting EVs from the host UMSC, the pellet was resuspended, and the suspension was measured for GALNS (a) or GUSB (b) activity. The EV-free supernatant of the isolation process contained no detectable GALNS or GUSB activities. Suspending the EVs in PBS contained a small amount of available GALNS and GUSB. Mechanical disruption by sonication increased the amount of available active GALNS enzyme. Finally, detergent-based lysis of EVs showed a significant increase in available active enzyme for both GALNS and GUSB. Error bars: mean ± SD. (*P < 0.05, **P < 0.01, ***P < 0.001, two-tailed unpaired t test with Welch’s correction)