Objective To study the effect of transforming growth factor β1 (TGF-β1) plasmid on poly frosted-defrosted allogenic nerve transplantation. Methods Forty Wistar rats were randomly divided into two groups equally. A 2.0 cm sciatic nerve segment, 5 mm away from infrapiriformis muscle space, was removed and the defect was repaired with poly frosteddefrosted allogenic nerve. The TGF-β1 plasmids were injected into the nerve anastomosis and adjacent muscles in the experimental group, normal saline in the control group. The nerve specimens were sectioned for staining in the 6th and 12th weeks . Axonal count and statistical analyses were done. Results The grafted and distal nerve segments showed regenerated fibers in both groups. In the experimental group,less edema and more nerve fibers were observed in the 6th week. The grafted nerve segment was filled with regeneration axons, the myelinated nerve fibers arranged regularly, and the axons and the myelin sheaths developed well in the 12th week. There was significant difference in the number of regenerating axons between the experimental group 98.6±4.8／μm2 and control group 75.8±5.1／μm2 (Plt;0.01). Conclusion Multiple frost-defrost of allogenic nerve can reduce its antigenicity and increase itsusefulness in repairing nerve defects. Local use of TGF-β1 plasmid can enhance immunosuppression to reduce immuno rejection.
