Mesenchymal stem cell-derived extracellular vesicles

Therapeutic benefits of mesenchymal stem/stromal cells (MSCs) are now widely believed to come from their paracrine signalling, i.e. secreted factors such as cytokines, chemokines, and extracellular vesicles (EVs). Cell-free therapy using EVs is an active and emerging field in regenerative medicine. The cellular environment of MSCs is of critical importance when directing paracrine activity. Typical 2D cultivation of stem cells on tissue culture plastic is far removed from the physiological environment of MSCs. The application of 3D cell culture allows MSCs to adapt to their cellular niche environment which, in turn, influences their paracrine signalling activity. In this study we evaluated the impact of 3D MSCs culture on EVs secretion and cargo proteome composition and functional assessment. The outcome highlights critical differences between MSC-EVs obtained from different culture microenvironments, which should be considered when scaling up MSC culture for clinical manufacturing.