高分子复合材料作为高效、安全的基因载体的研究
发布时间：2018-08-24 16:47
【摘要】：阳离子高分子作为一类重要的非病毒基因递送载体,具有很多优于病毒类载体的特点:无免疫原性、无致癌性、易于合成且稳定,因此在过去的几十年里得到巨大的发展。然而,阳离子高分子在实际应用过程中存在着转染效率和细胞毒性之间的恶性关联:(1)转染效率高的阳离子高分子载体,细胞毒性也高;(2)细胞毒性低的阳离子高分子载体,转染效率也低。因此打破这一恶性关联,开发出高效、低毒的阳离子高分子载体,成为基因治疗这一科学领域亟待解决的重要问题。为此我们提出一个解决思路:构建基于阳离子树形高分子的超分子体系,从而获得高效、低毒的高分子复合物。本文提出以下两种方法来构建超分子体系:(1)开发一种核-壳结构的高分子复合物:用高代数的树形高分子作为核心高分子,在低氮磷比下压缩质粒DNA以抵消其正电性,然后以低分子量的阳离子聚合物作为外壳高分子,包裹在外部。我们选用三种高代数(Generation,G)的聚酰胺-胺(PAMAM)树形高分子作为核心高分子,然后分别选用低分子量的线性聚乙烯亚胺(LPEI)、支状聚乙烯亚胺(BPEI)和G2PAMAM作为外壳做测试。结果发现复合物以G8PAMAM为核心高分子、LPEI为外壳高分子时,表现出较高的基因转染效率,并且细胞毒性很低。进一步的转染机制研究结果表明,这种核-壳结构有利于复合物在细胞质中释放DNA。(2)利用化学交联策略:将低代数的G2PAMAM与富勒烯C60化学交联,得到结构均匀的纳米颗粒,基因转染效率大为提高,且细胞安全性较好。进一步的转染机制研究表明,该交联产物大大提高了细胞对基因的摄入能力。本论文基于阳离子树形高分子提出了两种独特的策略,获得两种易于合成的转染复合物G8/LPEI/DNA和C60-G2/DNA,具有较高的细胞转染效率和较低的细胞毒性。后续我们将进一步评估这两种转染复合物的体内递送效率,并探索G2 PAMAM与富勒烯C60交联产物的光动力学治疗作用,为基因治疗联合光动力学治疗奠定良好的材料学基础。
[Abstract]:As a kind of important non-viral gene delivery vector, cationic polymer has many advantages over virus-like vectors: no immunogenicity, no carcinogenicity, easy synthesis and stability, so it has been greatly developed in the past few decades. However, there is a malignant correlation between transfection efficiency and cytotoxicity of cationic polymer in practical application: (1) cationic polymer carrier with high transfection efficiency and high cytotoxicity; (2) cationic polymer carrier with low cytotoxicity; The transfection efficiency was also low. Therefore, breaking this malignant association and developing cationic polymer carriers with high efficiency and low toxicity has become an important problem to be solved in the field of gene therapy. Therefore, we propose a solution: to construct a supramolecular system based on cationic dendrimer, so as to obtain highly efficient and low toxic polymer complexes. In this paper, the following two methods are proposed to construct supramolecular system: (1) to develop a core-shell polymer complex: high algebraic dendritic polymer is used as the core polymer, and the plasmid DNA is compressed at low nitrogen / phosphorus ratio to counteract its positive electrical properties. Then the cationic polymer with low molecular weight was used as the outer polymer. Three kinds of high algebra (Generation,G) polyamide-amine (PAMAM) dendrimer were selected as core polymers, and the low molecular weight linear polyethylene imine (LPEI), branched polyimide (BPEI) and G2PAMAM were used as the shell respectively. The results showed that when G8PAMAM was used as the core polymer and LPEI was used as shell polymer, the efficiency of gene transfection was higher and the cytotoxicity was very low. Further studies on the transfection mechanism showed that the core-shell structure was conducive to the release of DNA. (2) from the cytoplasm of the complex. (2) the low algebraic G2PAMAM was chemically crosslinked with fullerene C60 to obtain homogeneous nanoparticles. The efficiency of gene transfection was greatly improved, and the cell safety was better. Further studies on the transfection mechanism showed that the cross-linked product greatly increased the ability of the cells to ingest genes. Based on cationic dendrimer, two novel transfection complexes, G8/LPEI/DNA and C60-G _ 2 / DNA, have been proposed in this paper, which have high transfection efficiency and low cytotoxicity. We will further evaluate the delivery efficiency of these two transfection complexes in vivo, and explore the photodynamic effects of G2 PAMAM and fullerene C60 crosslinking products, which will lay a good material foundation for gene therapy combined with photodynamic therapy.
【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R450
本文编号：2201419
[Abstract]:As a kind of important non-viral gene delivery vector, cationic polymer has many advantages over virus-like vectors: no immunogenicity, no carcinogenicity, easy synthesis and stability, so it has been greatly developed in the past few decades. However, there is a malignant correlation between transfection efficiency and cytotoxicity of cationic polymer in practical application: (1) cationic polymer carrier with high transfection efficiency and high cytotoxicity; (2) cationic polymer carrier with low cytotoxicity; The transfection efficiency was also low. Therefore, breaking this malignant association and developing cationic polymer carriers with high efficiency and low toxicity has become an important problem to be solved in the field of gene therapy. Therefore, we propose a solution: to construct a supramolecular system based on cationic dendrimer, so as to obtain highly efficient and low toxic polymer complexes. In this paper, the following two methods are proposed to construct supramolecular system: (1) to develop a core-shell polymer complex: high algebraic dendritic polymer is used as the core polymer, and the plasmid DNA is compressed at low nitrogen / phosphorus ratio to counteract its positive electrical properties. Then the cationic polymer with low molecular weight was used as the outer polymer. Three kinds of high algebra (Generation,G) polyamide-amine (PAMAM) dendrimer were selected as core polymers, and the low molecular weight linear polyethylene imine (LPEI), branched polyimide (BPEI) and G2PAMAM were used as the shell respectively. The results showed that when G8PAMAM was used as the core polymer and LPEI was used as shell polymer, the efficiency of gene transfection was higher and the cytotoxicity was very low. Further studies on the transfection mechanism showed that the core-shell structure was conducive to the release of DNA. (2) from the cytoplasm of the complex. (2) the low algebraic G2PAMAM was chemically crosslinked with fullerene C60 to obtain homogeneous nanoparticles. The efficiency of gene transfection was greatly improved, and the cell safety was better. Further studies on the transfection mechanism showed that the cross-linked product greatly increased the ability of the cells to ingest genes. Based on cationic dendrimer, two novel transfection complexes, G8/LPEI/DNA and C60-G _ 2 / DNA, have been proposed in this paper, which have high transfection efficiency and low cytotoxicity. We will further evaluate the delivery efficiency of these two transfection complexes in vivo, and explore the photodynamic effects of G2 PAMAM and fullerene C60 crosslinking products, which will lay a good material foundation for gene therapy combined with photodynamic therapy.
【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R450
【参考文献】
相关期刊论文 前1条
1 张国华,谭小凡,沈冬,赵淑媛,时彦一,金彩科,孙惟谷,郭艳红,陈光慧,汤健;肌肉电脉冲转移入α2干扰素基因的表达和抗肿瘤作用(英文)[J];Acta Pharmacologica Sinica;2003年09期
，本文编号：2201419
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