Abstract

The Importance of Suitable Media for Exosome Production

Joo Youn Lee, CTO, Xcell Therapeutics Inc.

Mesenchymal stem cells (MSCs) are commonly used as a source of regenerative medicine due to their strong immunosuppressive and regenerative effects. Paracrine effect is one of the key mechanisms of MSC. Recently, it has been shown that the extracellular vesicles (EVs), which include exosomes and microvesicles, orchestrate the principle mechanisms of action of MSCs after infusion. These vesicles are involved in cell-to-cell communication, cell signaling, and altering cell or tissue metabolism at short or long distances in the body. Exosomes are nanoscale-specific lipid bilayer vesicles secreted by cells, with a diameter of 30-150 nm. The use of MSC-derived exosomes may provide several advantages over their counterpart live cells (MSC), potentially reducing undesirable side effects including immune reaction and low stability. However, for effective pharmaceutical research, only the target cell-derived exosomes must be produced and isolated, but contamination of animal/human component-derived exosomes already contained in cell culture media has reduced the purity of exosomes. Therefore, this study aims to introduce the ideal culture environment for the production of exosomes by cultivating MSCs in a serum-free chemically defined media (CDM) and confirming the characteristics of secreted exosomes. MSC derived exosome productivity was compared using several media including CDM. Wound healing assay and angiogenesis assay were conducted to evaluate the characteristics of the produced exosomes.