The Application Prospects and Challenges of Mesenchymal Stem Cell-Derived Exosomes in Spinal Cord Injury Repair.

Spinal cord injury (SCI) is a severe, disabling condition for which current treatments are largely insufficient in restoring neurological function. Despite advances in surgical and pharmacological interventions, no effective treatment currently exists to reverse neurological deficits caused by SCI. Mesenchymal stem cells (MSCs), especially human umbilical cord-derived MSCs (hucMSCs), have shown promise in tissue regeneration due to their multipotency and low immunogenicity. However, challenges such as low engraftment rates, tumorigenicity, and potential immune responses limit their clinical application. In recent years, mesenchymal stem cell-derived exosomes (MSC-Exos) have emerged as a promising therapeutic approach, demonstrating significant potential in SCI treatment. MSC-Exos exerts its therapeutic effects through mechanisms such as immune modulation, promotion of angiogenesis and axon regeneration, and reduction of blood-spinal cord barrier (BSCB) permeability. Furthermore, hucMSC-Exos demonstrate advantages in scalability, safety, and therapeutic efficacy, making them a promising cell-free approach for SCI repair. This review summarizes the biological properties of MSC-Exos, their roles in tissue injury repair, and their mechanistic contributions across different phases of SCI pathophysiology. Understanding these mechanisms will help pave the way for clinical translation of MSC-Exos as a novel and effective therapeutic strategy for SCI.