Extracellular vesicles for remote brain repair.

ABSTRACT

Recovery of brain function lost to disease or in old age is a challenging task in regenerative medicine. In the last two decades, therapeutic strategies have undergone significant shifts by a succession of major discoveries from adult neural stem cells and neurogenesis to the development of induced pluripotent stem cells to technologies for reprogramming cells in vitro and in vivo. Now, extracellular vesicles, small membrane-bound vesicles released by all cells and containing lipids, proteins, and nucleic acids, emerge as the next major technological opportunity. While substantial progress has been made on their potential use in therapy and EVs have entered many clinical trials, major aspects of their physiological role, in particular regarding their influence on brain function, remain unknown. However, a better understanding of their actual in vivo function, scope of communication, and possibilities to alter cellular processes in target cells will be needed. This review places EVs in the developing landscape of strategies for cellular repair of the brain and highlights their potential by looking at some recent progress in our understanding of their function in vivo.