SOX5 Overexpression in Schwann Cell Combined With Chitosan-Based Conduit Promotes Peripheral Nerve Regeneration

Severe peripheral nerve injury (PNI) remains a major clinical challenge, and functional recovery after conventional neurorrhaphy is often unsatisfactory due to fascicular mismatch, suture tension, and limited Schwann cell viability. To address these limitations, we previously developed a small-gap chitosan-based conduit that provides a controlled microenvironment for regenerative interventions. This study aimed to investigate whether SOX5 overexpression enhances Schwann cell regenerative potential and, when combined with this conduit, synergistically promotes peripheral nerve regeneration.

Schwann cells were transduced with SOX5 lentivirus and assessed for proliferation, migration, and neurotrophic factor secretion in vitro. In a rat sciatic nerve transection model (2-mm gap), animals received a chitosan conduit with intraluminal injection of SOX5 lentivirus. Histological, electrophysiological, and behavioral assessments were conducted at 12 weeks post-surgery.

SOX5 overexpression significantly enhanced Schwann cell proliferation, migration, and secretion of BDNF, NGF, CNTF, and VEGF, while maintaining the dedifferentiated repair phenotype. In vivo, the combination of SOX5 lentivirus and chitosan conduit improved axonal regeneration, reduced muscle atrophy, and increased conduction velocity and locomotor recovery relative to the empty conduit group.

Lentivirus-mediated SOX5 overexpression drives Schwann cells toward a repair phenotype and, when integrated with a small-gap chitosan-based conduit, effectively promotes structural and functional nerve regeneration.