Schwann cell strip for peripheral nerve repair

Many strategies have been investigated to provide an ideal substitute to treat a nerve gap injury. Initially, silicone conduits were used and more recently conduits fabricated from natural materials such as poly-3-hydroxybutyrate (PHB) showed good results but still have their limitations. Surgically, a new concept optimising harvested autologous nerve graft has been introduced as the single fascicle method. It has been shown that a single fascicle repair of nerve grafting is successful. We investigated a new approach using a PHB strip seeded with Schwann cells to mimic a small nerve fascicle. Schwann cells were attached to the PHB strip using diluted fibrin glue and used to bridge a 10-mm sciatic nerve gap in rats. Comparison was made with a group using conventional PHB conduit tubes filled with Schwann cells and fibrin glue. After 2 weeks, the nerve samples were harvested and investigated for axonal and Schwann cell markers. PGP9.5 immunohistochemistry showed a superior nerve regeneration distance in the PHB strip group versus the PHB tube group (< 10 mm, crossed versus 3.17+/- 0.32 mm respectively, P>0.05) as well as superior Schwann cell intrusion (S100 staining) from proximal (< 10 mm, crossed versus 3.40+/- 0.36 mm, P>0.01) and distal (< 10 mm, crossed versus 2.91+/- 0.31 mm, P>0.001) ends. These findings suggest a significant advantage of a strip in rapidly connecting a nerve gap lesion and imply that single fascicle nerve grafting is advantageous for nerve repair in rats.