背景:异体神经移植修复神经缺损,降低免疫排斥反应是关键问题之一,目前主要手段是降低移植神经段的抗原性和全身使用免疫抑制剂.目的:观察经反复冻融处理的冷藏异体神经移植,局部使用转化生长因子β1质粒处理的效果.设计:随机对照动物实验.单位:华中科技大学同济医学院附属协和医院手外科.材料:实验于2003-01/2004-12在华中科技大学同济医学院完成,选择健康成年不同窝的Wistar大鼠40只,随机分为实验组和对照组,每组各20只.方法:制备转化生长因子β1质粒及冷冻的异体坐骨神经.实验组和对照组大鼠将坐骨神经在梨状肌孔下0.5 cm处,切除2.0 cm,神经缺损用预制冷冻的异体神经2.0 cm移植修复,实验组局部肌肉及神经两断端注射转化生长因子β1质粒,对照组注射等量的生理盐水.分别于6,12周各组10只大鼠取材、切片、染色并进行轴索计数和统计学分析.结果:在实验过程中无动物死亡,均进入结果分析.6周时对照组神经移植段轴索间有轻度水肿,实验组轴索间基本无水肿,再生神经数量接近正常;12周时,实验组整个神经移植段基本被再生轴突充满,有髓纤维排列整齐,轴突和髓鞘发育良好,实验组再生轴突数显著高于对照组,差别具有极显著性[(98.6±4.8),(75.8±5.1)个/μm2,t=2.962,P＜0.01].结论:反复冻融冷藏保存可降低异体神经的抗原性,具有修复神经缺损的可能性.局部使用转化生长因子β1质粒,可在局部发挥免疫抑制作用,降低宿主的免疫排斥反应.%BACKGROUND: In repair of nerve defect with allogenic nerve graft, to reduce immune rejection is one of the key problems. At present, the main approach is to reduce antigenicity of grafted nerve segment and apply generally immune inhibitor.OBJECTIVE: To observe the effects of freeze/thaw treatment and local application of transforming growth factor beta 1 (TGF-β1) plasmid on frozen nerve allograft.DESIGN: Randomized controlled animal experiment was designed.SETTING: Department of Hand Surgery, Union Hospital, Tongji Medical College Affiliated to Huazhong University of Science and Technology.MATERIALS: The experiment was performed in Tongji Medical College of Huazhong University of Science and Technology from January 2003 to December 2004, in which 40 Wistar healthy and adult rats were employed,from different delivery and were randomized into experimental group and control, 20 rats in each one.METHODS: Transforming growth factor-β1 (TGF-β1) plasmid and frozen allogenic sciatic nerve were prepared. In experimental group and control,sciatic nerve was cut off 2.0 cm in length, in the foramen 0.5 cm beneath piriformis. The nerve defect was repaired with pre-frozen allogenic nerve 2.0 cm in length. In experimental group, TGF-β1 plasmid was injected in local muscle and two broken ends of nerve. In the control group, physiological saline of equal volume was injected. In the 6th and 12th weeks, the samples were collected from 10 rats in each group for sectioning, staining,axonal counting and statistical analysis.RESULTS: No any animal was died in experiment and all of animals entered result analysis. In the 6th weeks, in the control group, mild edema appeared among axons on the grafted segment of nerve and in the experimental group, there was no edema among axons and the regenerated nerve numbers were close to the normal. In the 12th week, in the experimental group, the entire grafted nerve segment was basically filled up by the regenerated axons;myelinated nerve fiber was arranged in order and both axons and myelins were developed well. The regenerated axonal count in experimental group was more significantly than the control, indicating extremely significant difference [(98.6±4.8), (75.8±5.1) counts/μm2, t=2.962, P ＜ 0.01].CONCLUSION: Freeze/thaw treatment can decrease antigenicity of allogenic nerve, which provides the possibility of repair of nerve defect. Local application of TGF-β1 plasmid can provide immune inhibition locally and reduce immune rejection in the host.
展开▼
