骨髓间充质干细胞快速粘附机制的研究及在骨修复中的应用

项目名称： 骨髓间充质干细胞快速粘附机制的研究及在骨修复中的应用

项目编号： No.30801175

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 无线电电子学、电信技术

项目作者： 干耀恺

作者单位： 上海交通大学

项目金额： 20万元

中文摘要： 节段性骨缺损一直是临床的难点，干细胞体外培养技术应用于临床目前仍受到技术上和伦理学的制约。本课题针对节段性骨缺损的难点，利用骨髓间充质干细胞（Mesenchymal stem cells, MSCs）快速粘附的特性，通过研究发现：1）不同材料对MSCs的快速粘附作用不同，其中RGD多肽修饰的PLGA和胶原纤维对细胞的快速粘附效率较高，而玻璃对细胞快速粘附效率较低，皮质骨片和磷酸三钙居中。作为节段性骨修复材料，具有一定空间结构、力学强度和低免疫源性的磷酸三钙是较为合适的选择。2）MSCs在初期的快速粘附效应中，细胞膜表面的粘附分子beta1-整合素起着较为重要的作用，通过单克隆抗体封闭法实验显示约72.5%±9.3%的细胞在beta1-整合素被封闭后，不能快速粘附在多孔生物陶瓷表面。3）同时设计出循环滤过筛选富集骨髓干细胞的过滤复合器，研究筛选出最佳的选择性富集参数。4）实验表明应用这种新型装置，可以在手术同期快速制备复合骨髓干细胞的生物活性材料，植入体内，可以修复羊胫骨的3cm长的节段性骨缺损，明显优于单纯浸滞骨髓血或单纯材料组。该成果获多项国家专利，并申请了国际专利，已申请临床转化。

中文关键词： 骨髓间充质干细胞；细胞粘附；干细胞筛选复合器；生物复合材料；骨再生

英文摘要： Large segmental bone defect always presents a major challenge in orthopaedics clinic. The clinical wide applications of stem cells culture in vitro for bone regeneration are still limited because of many problems, such as long culture time, contaminated risk, higher cost, and ethic problems. Centre around the rapid adhesion phenomenon of bone marrow mesenchymal stem cells (MSCs), we conducted some interesting researches. We found firstly rapid adhesion of MSCs depended on deferent materials. Using PLGA modified with RGD peptide and collagen, more MSCs adhered on these materials than glass, and the cortical bone chips, tri-calcium phosphate (TCP) presented medium activity in MSCs rapid adhesion. But as a bone substitute, TCP is a good artificial biomaterial with acceptable porous structure, mechanical strength, and low immunogenicity. Secondly, in the initial rapid adhesion effects of MSCs, beta1-integin of cell membrane surface played an important role. Monoclone antibody blocking experiment showed about 72.5%±9.3% MSCs could not selected by porous biomaterial under initial adhesion effect when beta1-integin blocked. Thirdly, an innovation of a disposable rapid stem cells screen-enrich- combined circulating system was developed, with an integrated series of optimal screen-enriching parameters. The new circulating system could rapid produce peri-operatively biomaterials combining with bone marrow MSCs, without culture in vitro process. Finally, when the MSCs-enriched biomaterial implanted back into the graft site during the same operation, the critical segmental bone defect (3cm large) was perfectly repaired in goat tibia experiment 6 months post-operatipon. It was much better than biomaterial soaking in bone marrow or biomaterial alone. This positive result won several national patents and applied also an international patent. Without culture in vitro, it shows easy, rapid, economic, safe and effective. Related devices are being tested in clinical trials.

英文关键词： mesenchymal stem cells; cell adhesion; stem cells screen-combined system;biomaterial;bone regeneration