髓核细胞与骨髓基质细胞移植对受损椎间盘退变的影响

Restraining Degeneration of Punctured Intervertebral Discs by Transplantation of Rabbit Nucleus Pulposus Cells and Marrow Stroma Cells

目的探讨移植兔骨髓基质细胞(MSC)和髓核细胞(NPC)对受损椎间盘退变的影响及影像学特点。方法采用原代细胞培养法获取并扩增NPC及MSC。2岁龄新西兰白兔随机分为3组:盐水注射组3只,MSC移植组6只,NPC移植组6只,L3/4、L4/5、L5/6椎间盘进行髓核穿刺抽吸后,分组注入盐水、MSC和NPC。未处理的L2/3、L6/7、L7/S1椎间盘作为对照组采集数据。术前及术后4、6、8周,相同条件下摄取腰椎侧位X光片,运用I mage-pro plus6.0测量椎间盘高度指数(DHI)计算%DHI;Merge eFil m Workstation测量MRI T2像椎间盘信号强度并进行标准化(ST2WI),计算%ST2WI。结果两细胞移植组较之盐水组均能够有效的抑制损伤椎间盘进行性的高度丢失、骨性终板破坏、骨赘形成、细胞外基质丧失等。NPC组第6周%DHI为(74.31±2.59)%,第8周为(79.29±2.53)%,两者间差异有统计学意义(P<0.05),提示8周时NPC组椎间盘高度恢复;且第8周时NPC组与MSC组的%DHI之差异无统计学意义。%ST2WI数据显示第8周时NPC组T2信号强度高于MSC组〔(70.63±7.60)%vs(54.32±7.92)%,P<0.05〕,提示NPC组细胞外基质的合成可能超过MSC组。结论NP及MSC两种细胞移植能够有效避免椎间盘损伤后发生的进行性的退变过程。8周后NPC组较MSC组显示出更强的基质合成能力,椎间盘高度及含水量出现恢复的迹象。提示外源性NPC能够良好的适应受体椎间盘环境,并发挥相应的细胞外基质分泌功能。

Objective To assess the ability of transplanted nucleus pulposus cells （NPC） and marrow stroma cells （MSC） in restraining the degeneration of punctured intervertebral discs in rabbits. Methods The passage 3 NPC and MSC were harvested for transplantation. Fifteen New Zealand white rabbits were divided into three groups： saline group （3）, MSC group （6） and NPC group （6）. The L3/4, L4/5, and L5/6 discs of the rabbits were stabbed and punctured using a 18G needle. The rabbits were then treated with saline, MSC, or NPC in their respective groups. The untreated L2/3, L6/7, and L7/S1 discs served as self controls. The lateral projection of lumbar vertebrae X rays and sagittal Nuclear Magnetic Resonance images of the lumbar verteral T2 weighed signals were collected before and 4, 6 and 8 weeks after the operations. The %DHI and standardized T2WI （ST2WI） were measured using Image-pro plus6.0 and Merge eFilm Workstation. Results All animals survived above 8 weeks after been transplanted. The transplantation effectively restrained the degeneration of the punctured discs. The NPC group had higher%DHI in week 8 （79.29±2.53）% than in week 6 （74. 31±2.59）% （P〈0.05）. However, no difference of % DHI appeared between the NPC and MSC group in week 8. The NPC group had stronger T2 weighed signals in week 8 than the MSC group. Conclusion Both NPC and MSC restrain the degeneration of punctured discs. NPC have shown stronger potential of extracellular matrix synthesis, and height and water content recovery of discs.