Stem cells and their extracellular vesicles as natural and bioinspired carriers for the treatment of neurological disorders

Abstract One of the most explored strategy to cure neurological disorders is the transplantation of stem cells and of their derived products. Different stem cells, as well as their extracellular vesicles (EV), modified or not, have been administrated in a large array of pre-clinical neurological disorder models. EV represent the hope of a “cell-free” therapy that would combine the therapeutic potential of stem cells without their drawbacks. Stem cells and EV showed various degrees of efficiency, but overall, provided benefits and improvements. The administration route has a considerable impact on stem cell and EV safety and therapeutic effect. However, despite evidences of pre-clinical success, the different strategies developed based on stem cells to treat neurological disorders do not exactly recapitulate in clinical trials. Discrepancies between pre-clinical and clinical experimental conditions and settings, cell availability and difficulties to scale-up and to produce cells and EV in a GMP environment limit translation.