Therapeutic Prospects of Stem Cell-Derived EVs: Upcoming Avenues, Promises, and Challenges

Stem cell therapies are gaining popularity around the world. There have been several clinical trials which have demonstrated the safety and efficacy of stem cells infusion. The most common type of stem cells employed in regenerative medicine are the adult sourced mesenchymal stem cells (MSCs). However, there are still several concerns with whole cell therapy, which therefore pave way for cell-free therapy. This involves the use of cellular products and derivatives, for e.g., extracellular vesicles (EVs). These membranes bound structures vary across a range of sizes lying mostly in the nanoscale and having various functionalities such as intercell communication, cellular clearance, and homeostasis. Extracellular vesicles include many diverse types of vesicles such as exomeres, exosomes, microvesicles, apoptotic bodies, etc. All of these being diverse in their functionality and cargo content serve differently in their applications. In case of stem cells, especially small EVs have found to mimic the regenerative action of their parent cells thereby gaining limelight for utility in clinical applications instead of the whole cells. Many preclinical and clinical studies have now validated the functional significance of small EVs in a diverse range of disease spectrum. However, there are still a lot of disparities in the isolation, characterization, and application of EVs which pose a challenge to their translational use. This article talks about the promising capabilities of MSCs-derived small EVs in regenerative therapeutics for various diseases and disorders as well as the challenges posed in their off-the-shelf utility.