Repairing rat sciatic nerve defects with the compound of acellular nerve graft and bone marrow mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND: Previous studies have successfully prepared the natural and biologically degraded acellular nerve graft and have proved the effect of promoting neural regeneration.OBJECTIVE: To construct tissue engineered artificial nerve with acellular nerve graft and bone marrow mesenchymal stem cells, and to observe the effect of promoting motor functional recovery and repairing rat sciatic nerve defects. DESIGN, TIME AND SETTING: Randomized control animal experiment was performed in the Medical TIssue Engineering Laboratory of the First Affiliated Hospital of Liaoning Medical University between June 2008 and February 2009. MATERIALS Wistar adult healthy male rats weighing 180-200 g were used to prepare acellular nerve graft, while Wistar adult healthy male rats weighing 100-120 g were used to prepare bone marrow mesenchymal stem cells. Tissue engineered artificial nerve was produced with acellular nerve graft co-cultured with bone marrow mesenchymal stem cells. METHODS: Sixty Wistar adult healthy male rats weighing 180-200 g were induced sciatic nerve defect models, 15 mm long. SD rats were divided into three groups at random with 20 animals in each group. ①Experiment group Rat sciatic nerve defects were bridged with tissue engineered artificial nerve. ②Blank control group Rat sciatic nerve defects were bridged with tissue engineered nerve scaffold. ③Autologous nerve control group Rat sciatic nerve defects were bridged with autologous nerve graft. MAIN OUTCOME MEASURES: At 12 weeks postoperation, the recovery of motor function was evaluated with gross observation, electrophysiology, histological observation and triceps surae wet weight.RESULTS: ①At 12 weeks postoperation, the toes at the operation side could separate and supported to the ground in the experiment group; there was no significant difference in the regenerated nerve conduction velocity between experimental group and autologous nerve graft group. ②At 12 weeks postoperation, histochemical stain results showed AchE-positive motor end-plate arranged regulady in the middle and superior part of gestrocnemius muscle to form end-plate zone in the experiment group. By use of silver staining, the regenerated nerve tract and the emergent branch were shown to be connected with motor end-plate.③There was no significant difference in the tibialis anterior muscle wet weight between experimental group and autologous nerve graft group. CONCLUSION: Bridging acellular nerve graft and bone marrow mesenchymal stem cells into rat sciatic nerve defects can promote motor functional recovery.