Enhanced reinnervation after neurotization with Schwann cell transplantation

We investigated the feasibility of using Schwann cell transplantation to enhance reinnervation after direct nerve-to-muscle neurotization (NMN). The denervated anterior tibial muscle was neurotized by tibial nerve implantation, and Schwann cell suspension (transplantation group) or an equivalent volume of culture medium (control group) was injected at the implantation site. In the control group, few axons invaded the muscle, demonstrating that skeletal muscle was poorly permissive to the advancement of axons. In the transplantation group, a large number of regenerating axons grew for a longer distance throughout the muscle, and reinnervated motor endplates were significantly more abundant. Enhanced reinnervation and functional recovery of the muscle in the transplantation group was confirmed by a significant increase in the compound muscle action potential and in muscle weight. These results suggest that intramuscular Schwann cell transplantation has potential as a cell therapy to improve functional recovery after NMN.