间充质干细胞移植中EGF、PDGF与HIF-1α、Ⅱ型胶原的量效研究

Dose effect of EGF,PDGF and HIF-1α,type Ⅱ collagen in transplantation of mesenchymal stem cell

目的探讨骨髓间充质干细胞（MSCs）移植在椎间盘退变修复过程中表皮生长因子（EGF）、血小板衍生因子（PDGF）与低氧诱导因子（HIF）-1α、Ⅱ型胶原的量效关系。方法用细针抽吸髓核构建兔椎间盘退变模型,体外培养MSCs,并采用绿色荧光蛋白（GFP）标记的腺病毒载体转染,标记MSCs。在模型构建成功2周后以每毫升5×106个细胞移植入退变椎间盘内。1、2、4、8周末用免疫荧光双染,并用激光共聚焦显微镜观测不同时间点MSCs中EGF、PDGF、HIF-1α、Ⅱ型胶原的表达及其变化规律。结果移植后MSCs中EGF、PDGF的表达在2周时达高峰,分别为（28.92±5.66）%、（40.77±8.13）%,随后下降;HIF-1α、Ⅱ型胶原缓慢上升,8周时达峰值,分别为（55.35±14.06）%、（37.23±9.53）%,2∽4周时上升速度最快。结论早期（2周时）MSCs以分泌营养细胞因子效应为主,后期（4周后）以发挥自我分化效应为主。

Objective To study the dose effect of epidermal growth factor（EGF）,platelet-derived growth factor（PDGF） and hypoxia-inducible factor（HIF）-1α,typeⅡcollagen in transplantation of mesenchymal stem cells（MSCs） during the repair of disc degeneration. Methods A rabbit model of disc degeneration was developed by fine-needle nucleus aspiration,the MSCs was cultured in vivo and transfected by adenovirus vector labeled with green fluorescent protein（GFP）. 2 weeks after successful devel-opment of rabbit model,5＆#215;106 mL-1 was transplanted into degenerated intervertebral disc. At the end of 1st,2nd,4th,8th week,im-munofluorescence and confocal laser scanning microscope were used to evaluate the expression and regularity of EGF,PDGF, HIF-1α,type II collagen in MSCs. Results At 2nd week,the expression of EGF and PDGF in MSCs hit the peak,which were （28.92±5.66）%and （40.77±8.13）%respectively,and then descended;the HIF-1αand typeⅡcollagen rose slowly,and peaked at the 8th week,which were（55.35±14.06）%and （37.23±9.53）%respectively,and the rising velocity was fastest during 2nd to 4th week. Conclusion The trophic effects play a major part in the MSCs in early（2nd week） period,then self differentiated effects play a ma-jor part in later regeneration（4 weeks later）.