Therapeutic and Drug-Delivery Applications of Extracellular Vesicles in the Brain, Lung, and Liver

Extracellular vesicles (EVs), encompassing exosomes, microvesicles, and apoptotic bodies, are pivotal mediators of intercellular communication, facilitating the transfer of nucleic acids, proteins, and lipids between cells and thereby influencing a wide range of physiological and pathological processes. Their inherent biocompatibility, nanoscale size, and ability to reflect the molecular signatures of their parental cells have positioned EVs as promising therapeutic agents for various diseases, including neurological, cardiovascular, hepatic, and pulmonary disorders, for which conventional therapies often provide limited or nonspecific benefits. Notably, EVs can traverse biological barriers such as the blood-brain barrier, enhancing their clinical applicability by enabling drug delivery to anatomically protected sites. Furthermore, patient-derived EVs exhibit distinct molecular profiles compared with healthy controls, underscoring their potential as diagnostic biomarkers and modulators of disease pathogenesis, with growing evidence demonstrating their ability to distinguish disease subtypes, predict prognosis, and monitor therapeutic responses. Accumulating evidence also indicates that EVs regulate immune responses, angiogenesis, and tissue remodeling, thereby contributing to both physiological homeostasis and pathological processes. Engineered EVs further offer innovative drug delivery solutions by improving therapeutic precision while minimizing adverse effects associated with conventional systems, and they hold considerable promise for future personalized- medicine strategies. This review summarizes current knowledge on the diverse roles of EVs across major organ diseases, highlights their translational potential as both therapeutic agents and biomarkers, and discusses emerging challenges that must be addressed for successful clinical translation. By providing a comprehensive overview, this study aims to advance the clinical translation of EVs in precision medicine.