Joint Use of a Chitosan/PLGA Scaffold and MSCs to Bridge an Extra Large Gap in Dog Sciatic Nerve

Background. Tissue-engineered nerve grafts (TENGs) constitute a promising alternative to nerve autografts that are recognized as the gold standard for surgical repair of peripheral nerve gaps. Objective. To investigate the feasibility of using TENGs for bridging extra large peripheral nerve gaps in large animals. Methods. TENGs were constructed by incorporating autologous bone marrow mesenchymal stem cells (MSCs) into a neural scaffold that consisted of a chitosan conduit inserted with poly(lactic-co-glycolic acid) (PLGA) fibers. A 60-mm-long sciatic nerve gap in dogs was bridged by TENGs, chitosan/PLGA scaffolds, or nerve autografts. At 12 months postsurgery, behavioral analysis, electrophysiology, retrograde fluorogold tracing, and histological examination were performed. Results. The outcomes of TENGs were similar to those of autografts and better than those of scaffolds alone. Conclusion. Introduction of autologous MSCs to a chitosan/PLGA scaffold improved the repair and rehabilitation of a large gap after peripheral nerve injury in dogs. Autologous MSCs may be a source of support cells for neural tissue engineering.