Ultracentrifugal separation, characterization, and functional study of extracellular vesicles derived from serum-free cell culture.

Extracellular vesicles (EVs) play important roles in extracellular trafficking and signaling. Here, we separate EVs by differential centrifugation. EVs separated by this approach are called large EVs (l-EVs) and small EVs (s-EVs), reflecting particle size, which sediment based on different ultracentrifugation forces. The resulting EVs can be quantified and analyzed using nanoparticle tracking analysis, immunoblotting, and functional assays. This protocol was applied to a suspension cell line with high transfection efficiency adapted to a high-density, serum-free culture. For complete details on the use and execution of this protocol, please refer to Nishimura et al. (2021).