中文摘要：

背景：聚左旋乳酸材料有良好的支撑作用,具有三维模板作用,为细胞黏附、增殖和分化提供场所。目的：以人脐带间充质干细胞作为种子细胞、多孔聚左旋乳酸作为支架材料构建组织工程化骨异位成骨的可行性及效果。方法：制备聚左旋乳酸多孔支架材料。用酶消化法分离培养人脐带间充质干细胞,传代培养、鉴定及诱导成骨,ALP染色检测骨向分化。将人脐带间充质干细胞与聚左旋乳酸材料复合培养,MTT及扫描电镜检测细胞增殖和细胞材料复合情况,应用矿化诱导7d的细胞材料复合物植入兔大腿肌袋模型观察组织工程骨的异位成骨能力。4周后应用组织学观察新骨的形成情况。结果与结论：与聚左旋乳酸多孔支架材料复合的人脐带间充质干细胞生长良好,细胞增殖未受影响,扫描电镜示细胞在支架材料上吸附、生长良好。体外对人脐带间充质干细胞骨向诱导后ALP染色阳性。矿化诱导的人脐带间充质干细胞复合聚左旋乳酸材料植入动物4周时,形成明显的块状组织,质地坚硬。组织学检查见新形成的组织有成骨细胞及其周围有血管长入。提示聚左旋乳酸多孔材料对种子细胞人脐带间充质干细胞的增殖无影响;人脐带间充质干细胞细胞与聚左旋乳酸多孔材料复合体可在异位形成骨组织。

英文摘要：

BACKGROUND：Poly-L-lactide（PLLA） material has good supporting effect and provides place for cell adhesion,proliferation and differentiation as 3-D template action.OBJECTIVE：To study the feasibility and results of ectopic bone formation of PLLA porous scaffolds combined with human umbilical cord mesenchymal stem cells（hUCMSCs）.METHODS：PLLA porous scaffolds were prepared.The hUCMSCs were isolated from human umbilical cord by collagenase digestion.After serial subcultivation in vitro,the hUCMSCs were passaged and identified.Then induce their osteogenic differentiation,be tested and evaluated by specific staining methods.The PLLA porous scaffolds combined with hUCMSCs were implanted into thighs of rabbits at 7 days after osteogenic induction.The bone formation was observed by histopathologic study at 4 weeks after operation.RESULTS AND CONCLUSION：hUCMSCs grew well on the surface of the PLLA porous scaffolds.These cells were positive for alkaline phosphate staining after osteogenic induction.The mineralized PLLA porous scaffolds combined with hUCMSCs formed obvious block tissues at 4 weeks after implantation,which was hard and constituted of blood vessels examined by histological examination.It is revealed that PLLA porous scaffolds have not affect hUCMSCs proliferation;PLLA porous scaffolds combined with hUCMSCs exhibit the greatest ectopic osteogenesis potential in vivo.