人脐血间充质干细胞移植对骨折愈合作用的实验研究

Experimental study of human umbilical cord blood mesenchymal stem cell transplantation on fracture healing

目的探讨人脐血间充质干细胞(HUCBMSCs)移植对兔骨折愈合的作用,为进一步实验及临床应用提供理论依据。方法采用密度梯度离心和贴壁培养法在无菌条件下从脐带血中分离培养HUCBMSCs,取第3代细胞进行实验。制作新西兰大白兔胫骨横断骨折模型,随机分为骨折端注射1×1010L-1HUCBMSCs悬液组(A组)和等量生理盐水组(B组)。细胞移植后第2,4,6,8周时2组随机抽取6只白兔进行X射线检查、生物力学检测、组织学观察骨折愈合情况及骨痂形成情况。结果第2—8周X射线检查及骨折愈合X射线评分结果显示A组的骨折愈合速度明显快于B组(P<0.05);组织学观察及评分结果显示A组骨折愈合进程比B组快(P<0.05),愈合质量比B组好(P<0.05);生物力学结果示细胞移植后第4,6,8周时A组最大破坏载荷均高于B组(P均<0.05),第4,6周时A组最大位移均高于B组(P均<0.05)。结论 HUCBMSCs在骨折愈合中发挥了促进作用,对预防骨折延期愈合或骨不连具有重要作用。

Objective It is to explore the effect of Human umbilical cord blood mesenchymal stem cells（ HUCBMSCs） on fracture healing in rabbits,and to provide a theoretical basis for further experiments and clinical application. Methods HUCBMSCs from umbilical cord blood by density gradient centrifugation were isolated and cultured under sterile conditions and the 3rd generation cells were taken for experiments. New Zealand white rabbits were selected to establish models of transverse fracture of tibia and were randomly divided into HUCBMSCs group（ group A） which was injected with 1 × 1010L-1HUCBMSCs suspension from fracture endpoint and the normal saline group（ group B） which given normal saline. On the 2nd,4th and6 th and 8th weeks after cell transplantation,six rabbits in each group were randomly selected to perform on X-ray examination and biomechanical testing and observe fracture healing and callus formation by histological examination. Results The X-ray examination from the 2nd to 8th week and X-ray fracture healing score results showed than： the fracture healing rate of group A was faster than that of group B（ P 0. 05）; Histological observation and the results showed that the speed and quality of fracture healing were better in group A than that in group B（ P 0. 05）; The biomechanical tests showed that the maximum damage on the load at 4th,6th and 8th weeks after cell transplantation of group A were higher than that of group B,the maximum displacement of group A at 4th and 6th weeks were higher than that in group B（ P 0. 05）. Conclusion HUCBMSCs play a catalytic role in fracture healing and an important role in preventing delayed fractures healing or bone nonunion.