Preparation and characterization of extracellular vesicles and their cutting-edge applications in regenerative medicine

Extracellular vesicles (EVs) are biologically active nanoparticles secreted by cells, which have a variety of physiological functions, such as promoting cell proliferation, regulating immunity, anti-inflammation, and facilitating angiogenesis. However, the application of EVs is limited by defects such as low therapeutic efficiency, lack of targeting, and unstable therapeutic effects. In recent years, various engineering methods have been developed to enhance the function of EVs. In addition, the research on the isolation methods and mechanisms of EVs has also made significant progress. In this paper, we review the biogenesis, composition, and isolation techniques of EVs, summarize the potential therapeutic mechanisms of natural EVs as well as the engineering strategies for EV modification, and highlight the recent advances in the application of EVs in tissue regeneration. Finally, we discuss EVs' current problems and future perspectives in regenerative medicine.