腺相关病毒介导的骨形态发生蛋白-2体内转染兔退变椎间盘的实验研究

目的 观察腺相关病毒介导的骨形态发生蛋白-2(AAV-BMP-2)基因对兔退变腰椎间盘的治疗作用.方法 将36只新西兰大白兔L2-3、L3-4、L4-5、L5-6椎间盘针刺制造退变模型后随机分为3组,其中12只注射AAV-BMP-2作为实验组,12只注射AAV作为实验对照组,12只注射生理盐水作为空白对照组.注射后的2、4、8周各组随机抽取4只兔行腰椎MRI扫描,扫描后将其处死,取L2-3、L3-4、L4-5、L5-6椎问盘髓核组织,用间苯三酚分光光度法检测髓核组织中的蛋白多糖含量.结果 在MRI影像学Thompson分级评估中,实验组各时间点椎间盘MRI信号比较,差异无统计学意义.实验对照组和空白对照组各时间点MRI信号比较,差异有统计学意义.实验组和实验对照组、实验组和空白对照组各时间点MRI髓核信号比较,差异有统计学意义;实验对照组和空白对照组比较,差异无统计学意义.在蛋白多糖含量测定中,实验组蛋白多糖含量在各时间点均高于实验对照组和空白对照组,实验对照组和空白对照组蛋白多糖均随时间的变化逐渐减少,各时间点两组比较无明显区别.结论 AAV-BMP-2对兔退变的腰椎间盘有治疗作用.

Experimental study of BMP-2 gene mediated by adeno-associated virus on the rabbit intervertebral disc degeneration

Objective To evaluate the potential of bone morphogenetic protein-2(BMP-2)gene therapy application on rabbit interverbral disc degeneration,using the recombinant Adeno-associated virusvector expressing BMP-2.Methods L2-3,L3-4,L4-5,L5-6 lumbar discs of 36 skeletally mature New Zealand white rabbits were punctured to set up interverbral disc degeneration model.Subsequently,36 rabbits were randomly divided into three groups.Group 1(n=12)were injected with the Adeno-associated virus expressing BMP-2,Group 2(n=12)were injected with Adeno-associated virus only while Group 3(n=12)were injected with saline.Four rabbits were randomly selected from each group after iniection 2 weeks,4 weeks and 8 weeks respectively,and killed after lumbar MRI scanning.The L2-3,L3-4,L4-5,L5-6 lumbar discs of each rabbit was collected.Speetrophotometry were performed to determine proteoglycan synthesis.Results In Group 1,there were no significant difference in magnetic resonance imaging(MRI)at all time points.In constrast,in Group 2,Group 3,there were significant differences in MRI at all time points.The comparison among these three group showed that there were significant differences between Group 1 and Group 2,Group 1 and Group 3,while there were no significant differences between Group 2 and Group 3.The proteoglycan quantity in the nucleus pulposus comparison showed that there were significant differences between Group 1 and Group 2,Group 1 and Group 3,while there was no significant differences between Group 2 and Group 3.Conclusion Our study indicates that BMP-2 gene mediated by adeno-associated virus induced a restoration of intervertebral disc degeneration.