Regenerative potential of chitosan-coated poly-3-hydroxybutyrate conduits seeded with mesenchymal stem cells in a rat sciatic nerve injury model

Objectives: A number of chemical and biological factors, including mesenchymal stem cells (MSCs), have been developed to enhance nerve regeneration by introduction through a variety of nerve conduits. This study was designed to assess the efficacy of using chitosan-coated poly-3-hydroxybutyrate (PHB) nerve conduits seeded with human bone marrow-derived MSCs (hMSC-bm) to augment repair in an experimental rat model of sciatic nerve injury.Methods: A total of 30 rats were randomly assigned to one of three groups (n = 10). In each rat, a 10mm segment of the sciatic nerve was removed and was replaced by a chitosan-coated PHB conduit seeded with hMSC-bm (PHB/chitosan-hMSC-bm group), a chitosan-coated PHB conduit (PHB/chitosan group), or an autograft (autograft group) as the control. The results were evaluated 8 weeks postoperatively by observation, electromyography and histologic examination with light microscopy and immunostaining.Results: Histologic examination showed that both PHB/chitosan-hMSC-bm conduits and PHB/chitosan conduits led the damaged axons through the injured area. When the effects were compared, the results with the PHB/chitosan-hMSC-bm conduits were superior to those with the PHB/chitosan conduits (p < 0.05) but not as successful as with the autologous nerve grafts (p < 0.05).Conclusion: PHB/chitosan-hMSC-bm nerve conduits may be a useful artificial guide for nerve regeneration.