新型多羟基超支化非病毒基因载体的构建及其在引导骨组织再生材料中应用的初步研究

阳离子聚合物是目前非病毒基因载体研究的主要领域，其发展趋势是具备更高的转染效率和更低的细胞毒性。本项目拟用多环氧基和多氨基的化合物，通过开环加成反应，制备系列低毒高效的新型多羟基超支化阳离子聚合物，研究反应条件对于聚合物分子结构、细胞转染能力和细胞毒性的影响，从中筛选出高效低毒的基因载体，并利用所得的系列聚合物基因载体携带骨形态发生蛋白基因转染骨髓间充质干细胞，研究其对细胞成骨分化的影响。将基因载体与引导骨组织再生材料结合，利用电纺丝法制备基因活化的纳米纤维支架，通过控制电纺丝过程中的各项参数，达到调控基因载体释放行为的目的。通过本项目的研究，有望获得系列低毒高效的新型多羟基超支化非病毒基因载体，并初步应用于引导骨组织再生材料中。

In recent years, the research of non-virus gene vector focuses on cationic polymers, whose development tendency is to increase the efficiency and reduce the toxicity of gene vector. In this project, a series of novel multi-hydroxyl hyperbranched cationic polymers will be synthesized under different conditions by the ring-opening addition process of reagents with multi-epoxy and multi-amino groups. The effects of reaction conditions on molecular structure, transfection efficiency and cell toxicity will be studied. Among these cationic polymers, the ones with high efficiency and low toxicity will be chosen as gene vectors and deliver the bone morphogenic protein gene into bone marrow mesenchymal stem cells (BMSC), and then the osteogenic differentiation of BMSCs will be comprehensively assessed. Moreover, in order to integrate gene vector with guided bone regeneration scaffolds, gene-activated scaffold will be prepared by electrospinning. The releasing behavior of gene vectors from the scaffold will be regulated by the conditions of the electrospinning process. Through this project, a series of novel multi-hydroxyl hyperbranched non-virus gene vectors with high efficiency and low toxicity could be developed and preliminarily applied in guided bone regeneration scaffold.