Development of Schwann cell-seeded conduit using chitosan-based biopolymers for nerve repair

The purpose of this study is to develop biodegradable nerve guidance conduits seeded with Schwann cells (SC) using chitosan-based biopolymers for improving nerve regeneration. Chitosan, prepared from alkaline hydrolysis of chitin, is a natural polysaccharide biopolymer, having biocompatibility and biodegradability. In this study, chitosan and chitosan-gelatin membranes were prepared, characterized, and evaluated. The SC isolated from rat sciatic nerve was seeded on chitosan and chitosan-gelatin membranes to investigate their interactions. To enhance the SC attachment and growth on the membranes, we incorporated the poly-L-lysine (PLL) into chitosan and chitosan-gelatin network at various ratios of 1:800, 1:200, 1:50 (chitosan or chitosan-gelatin: PLL). We have also investigated the effect of extracellular matrix (ECM) molecules on the proliferation of SC. We observed that SC proliferation on PLL-coated surface was significantly higher than that of ECM coated and uncoated surfaces. With the increase of PLL ratio into chitosan or chitosan-gelatin network, the attachment and growth of SCs were significantly enhanced. This study indicates that the incorporation of PLL into chitosan and chitosan-gelatin membranes significantly improves the bioactivity of the materials. The Schwann cell-seeded films can be used to construct a three-dimensional nerve conduit for enhancing nerve regeneration.