Mechanistic analysis of extracellular vesicles derived from a clonal MSC line

Mesenchymal stromal cells (MSCs) derived extracellular vesicles (EVs) are nano-sized, membrane-bound carriers that can be considered a novel therapeutic. In particular, these EVs show the pro-regenerative and anti-inflammatory therapeutic benefits of MSCs whilst remaining a safer and cheaper cell free therapy with an excellent delivery method. There is a high level of interest in EVs being able to combine the potency of stem cell treatment with the practicality of a pharmaceutical. However, progress is hindered due to problems with consistency and scalability.
This study focuses on an immortalised clonal MSC line called Y201s which releases a constant supply of EVs with pro-regenerative and anti-inflammatory properties. Such mechanisms could be argued to be related to the corona of proteins on the surface of EVs.
Therefore, this project will focus on the analysis of Y201-derived EV mechanisms of action with a distinct focus on corona proteins. We will aim to identify core EV proteins present within the corona and use EV shaving techniques to remove proteins within the corona, target and manipulate candidate functional EV proteins to determine mechanism of action.
This research led to multiple key ECM proteins being identified on the EV corona, involved in a multitude of binding and pathways. RGD proteins are not as involved in mechanisms of action as previously thought. EVs can be partially shaved through proteinase k treatment without affecting size, integrity or function. Finally HSPG2 has a key role in the pro-regenerative effects produced by Y201 EVs. This work has proven important as it highlights a key mechanism of action and opens up more avenues for further research into the importance of the corona.