Biology and Therapeutic Potential of Exosomes, Targeted Drug Delivery

Abstract

Exosomes are small vesicles released by various cell types—compounds of a lipid bilayer and surface proteins that facilitate their recognition, direction, and uptake by the target cell. Inside, exosomes contain proteins, lipids, and nucleic acids, the composition of which varies depending on the cell of origin. Exosomes can be internalized by the target cell by endocytosis, fusion, or ligand–receptor interaction. The main functions of these extracellular vesicles (EVs) are intercellular communication, gene regulation, and the activation of cell regeneration and repair processes. Due to these characteristics, exosomes emerge as a promising option for the treatment of various diseases. Therefore, this review addresses the biology of exosomes and provides examples of studies with the molecular mechanisms by which these vesicles are taken up by target cells; examples of factors that influence the secretion and molecular composition of exosomes, which can be modified through exosome engineering, to enhance their effects. Furthermore, it addresses a diverse range of examples of the potential therapeutic applications of exosomes, including those loaded with different types of molecules, to use them as vehicles for drug delivery, with the objective of achieving safer, more precise, and effective treatments. Finally, it includes some clinical studies conducted with exosomes.