Repairing rat sciatic nerve defects via transplanting bilayer collagen conduit scaffolds carrying bone marrow mesenchymal stem cells

Objective To construct an artificial nerve graft as an alternative for autologous nerve grafting. Methods We fabricated an innovative tissue engineered nerve graft (TENG), which consists of a commercial bilayer collagen membrane (Bio-Gide)-based nerve scaffold and bone marrow mesenchymal stem cells (BMSCs) serving as support cells to bridge a 10 mm long sciatic nerve defect in rats, The 10 mm gap was left empty after resection in the blank group. In the other three groups, the sciatic nerve defect was, respectively, bridged with plain collagen tube (CT group), a collagen tube filled with BMSC suspension (C+ CT group), or reversed transected nerve segment (AG group). Results Histological and functional assessments showed that the developed TENG facilitated nerve regeneration (SFI: CT, -92.490±1.836; C+ CT, -70.010±7.805; AG, -70.130±8.744; F= 17.850, P 0.05) and better outcomes than the plain collagen tube (P<0.05). Conclusion These results manifested that the bilayer collagen conduit loaded BMSCs could be applied as a new biodegradable artificial nerve guide for nerve tissue engineering. Key words: Tissue engineer; Nerve graft; Bone marrow mesenchymal stem cells; Bilayer collagen conduit scaffold; Sciatic nerve injury; Peripheral nerve regeneration