Stem cell-derived exosome transplantation as a new cell-free therapy for liver regeneration

Stem cell transplantation has been used to treat some diseases with promising results. Stem cells stem cells can rescue injured tissues through various mechanisms, such as stimulation of growth factor secretion, activation of other/local stem cells, differentiation into specialized cells, and modulation of the immune system. However, stem cell transplantation also carries risks related to immune rejection as well as tumorigenesis. In recent years, more evidence has suggested that transplantation of stem cell-derived exosomes can induce effects similar to stem cell transplantation. Particularly, exosomes are less immunogenic than the parent cells due to their low content of membrane proteins. This review aims to summarize the characteristics of exosomes, including their physiological functions, and to highlight the therapeutic effects of exosome injection in hepatic regeneration.