Comparative study of commercial protocols for high recovery of high-purity mesenchymal stem cell-derived extracellular vesicle isolation and their efficient labeling with fluorescent dyes

Nanomedicine. 2021 Apr 15;102396. doi: 10.1016/j.nano.2021.102396. Online ahead of print.

Abstract

The extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) can be used as carriers for therapeutic molecules and drugs to target disordered tissues. This aimed to compare the protocols used for isolation of MSC-derived EVs by comparing EV collection conditions and three commercial purification kits. We also determined appropriate fluorescent dyes for labeling EVs. MSC-derived EVs were efficiently secreted during cell growth and highly purified by the phosphatidyl serine-based affinity kit. Although the EV membrane was more efficiently labeled with the fluorescent dye PKH67 compared to other probes, the efficiency was not enough to accurately analyze the endothelial cellular uptake of EVs. Results verified the easy protocol for isolating and fluorescently labeling EVs with commercial reagents and kits, but meanwhile, further modification of the protocol is required in order to scale up the amount of EVs derived from MSCs using fluorescent probes.

Keywords: Drug delivery; Exosome; Extracellular vesicle; Mesenchymal stem cell; Regenerative medicine.