Mesenchymal Stem Cell-Derived Exosomes: A Novel Frontier in Regenerative Medicine and Immunotherapy

Mesenchymal stem cells (MSCs) are a heterogeneous cell population that can be isolated from various tissues, including adipose tissue and bone marrow. Their ease of isolation and robust ex vivo expansion make MSCs an attractive candidate for regenerative and therapeutic applications, particularly in tissue repair and angiogenesis. Increasing evidence indicates that the therapeutic effects of MSCs are largely mediated through the secretion of extracellular vesicles, especially mesenchymal stem cell-derived exosomes (MSC-Exos). These exosomes contain diverse bioactive molecules, including proteins, nucleic acids, and lipids, which contribute to their regenerative, immunomodulatory, and therapeutic potential. Preclinical studies have demonstrated that MSC-Exos promote tissue repair, regulate immune responses, and alleviate pathological conditions associated with cardiovascular diseases, neurological disorders, musculoskeletal injuries, and immune-mediated diseases. The outcomes of these studies suggest that MSC-Exos represent a promising and effective therapeutic modality for a broad range of diseases. Compared with conventional MSC-based therapies, MSCExos offer several advantages, including reduced immunogenicity, lower tumorigenic risk, improved stability, and easier storage and handling, making them particularly suitable for clinical translation. This review provides a comprehensive overview of the current clinical and translational landscape of MSC-Exos therapy, highlighting their therapeutic applications, underlying mechanisms, and key challenges that must be addressed to facilitate successful clinical implementation. Collectively, the emerging evidence underscores the potential of MSC-Exos to advance regenerative medicine and suggests that exosome-based therapies may represent a transformative approach for the treatment of diverse human diseases.