多样化运用UTMD在慢性肝损动物模型中促进骨髓间充质干细胞归巢及调控定向分化的实验研究

项目名称： 多样化运用UTMD在慢性肝损动物模型中促进骨髓间充质干细胞归巢及调控定向分化的实验研究

项目编号： No.81471666

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 李凡

作者单位： 上海交通大学

项目金额： 73万元

中文摘要： 骨髓间充质干细胞是治疗终末期肝病的理想种子细胞，目前制约其发展的难题是在持续肝损状态下细胞归巢困难及分化方向不确定。解决此问题的关键是①干细胞周围具备定向分化因子的稳定浓度②协同增强肝组织和干细胞归巢能力。申请人前期利用超声靶向破坏微泡(UTMD)联合重组腺相关病毒(rAAV)实现了基因在多潜能干细胞的稳定表达；本课题将以此为基础，对上述难题展开研究：建立慢性肝损动物模型；利用UTMD增强携带肝细胞生长因子（HGF）的rAAV转染骨髓间充质干细胞，HGF稳定表达使干细胞持续向肝细胞定向分化；借助UTMD辐照及HGF联合作用使骨髓间充质干细胞表面趋化因子/受体表达增多，细胞主动归巢能力增强；采用UTMD定位辐照进一步诱导肝组织血管壁出现分子邮政编码，增加干细胞归巢的吸引力；同时探讨UTMD促进干细胞分化及归巢中Wnt信号通路的参与机制；从而为骨髓间充质干细胞治疗终末期肝病探索出新的思路。

中文关键词： 超声治疗；骨髓间充质干细胞；重组腺相关病毒；肝细胞生长因子；信号通路

英文摘要： Bone marrow-derived mesenchymal stem cells (BM-MSCs) are ideal seed cells for the cell transplantation therapy of end-stage liver diseases. The bottleneck problem of this research currently includes: the undefined proliferation of BM-MSCs in vivo and the difficulty of homing into injured liver. The keys to solve the problem are①the stable concentration of regulating the oriented differentiation around the stem cells②the cooperative reinforcement of homing ability of injured liver and stem cells. The applicant previously demonstrated that enhancement effect and stable expression of exogenous genes in pluripotent stem cell was achieved by the ultrasound targeted microbubble destruction combining recombinant adeno-associated virus. Based on our previous original results, we will carry on further study to solve above-mentioned problems. We will establish the animal models of chronic liver injury, and then employ UTMD technique to promote the transfection of rAAV encoding hepatic growth factor(HGF) into BM-MSCs. The oriented differentiation of BM-MSCs into hepatic cells will be continuously stimulated by the stable expressing HGF. Meanwhile, the homing ability of BM-MSCs themselves will be enhanced by the upregulation of chemotatic factors and the corresponding receptors on the cell surface which through the irradiation of UTMD and secreted HGF. In addition, the application of UTMD irradiation on liver will increase the potential of attracting BM-MSCs from circulation by the occurrence of molecular zip code on the vessel wall in the injured livers, which will further promote the homing effect of BM-MSCs. The applicant will deeply investigate the mechanism of UTMD inducing the change of biological characteristics of BM-MSCs, through observing the involvement of Wnt/β-Catenin signaling pathway in relation with the proliferation and the differention of BM-MSCs, in order to provide a new method for the therapy of end-stage liver diseases by BM-MSCs transplantation.

英文关键词： ultrasound therapy;bone marrow derived mesenchymal stem cell;recombinant adeno-associated virus;hepatic growth factor;signaling pathway