Multifaceted Role of Extracellular Vesicles: Intercellular Messengers to Therapeutic Applications: A Narrative Review

Background and Aims: Extracellular vesicles (EVs) are nanoscale carriers, including exosomes, microvesicles, and apoptotic bodies, that mediate intercellular communication by transporting proteins, nucleic acids, lipids, and metabolites. They regulate immunity, tissue repair, and cell differentiation. Increasing evidence highlights their dual roles in disease, where they may promote tumor growth and immune evasion but also serve as diagnostic and therapeutic tools. This review synthesizes advances in EV biology, their roles in health and disease, and their therapeutic potential. Methods: We conducted a narrative review of recent literature, focusing on EV isolation methods, biological functions, and clinical applications. Sources were selected to capture both mechanistic insights and translational perspectives. Results: Advances in isolation technologies, from ultracentrifugation to microfluidics, have improved the precision of EV characterization. EVs exhibit distinct molecular signatures, positioning them as promising biomarkers in cancer, cardiovascular, neurodegenerative, autoimmune, and infectious diseases. Mechanistic studies demonstrate their roles in immune modulation, tissue remodeling, and regeneration. As therapeutic agents, EVs show promise as drug delivery systems and as platforms for gene and immunotherapies, offering enhanced targeting and reduced toxicity compared to synthetic nanoparticles. Engineered EVs and hybrid EV-liposome systems further expand their applications, though challenges persist in scalability, standardization, and safety. Conclusion: EVs are central mediators of intercellular communication with transformative potential in diagnostics and therapeutics. Their biological properties position them as valuable biomarkers and delivery vehicles in precision medicine. Overcoming translational challenges, such as immunogenicity, oncogenic risks, and manufacturing limitations, will be essential for their successful clinical integration.