Novel shielded transferrin-polyethylene glycol-polyethylenimine/DNA complexes for systemic tumor-targeted gene transfer
Novel shielded transferrin-polyethylene glycol-polyethylenimine/DNA complexes for systemic tumor-targeted gene transfer
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DOI：
10.1021/bc0256087
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发表时间：
2003-01-01
影响因子：
4.7
通讯作者：
Wagner, E
中科院分区：
文献类型：
--
作者：
Kursa, M;Walker, GF;Wagner, E
肿瘤靶向DNA复合物可以通过稳定成分的混合和冻融轻松生成，这对于其后续作为医疗产品的应用非常有利。通过混合质粒 DNA、作为主要 DNA 缩合剂的线性聚乙烯亚胺（PEI22，22 kDa）、用于表面屏蔽的 PEG-PEI（聚（乙二醇）缀合的 PEI）和为受体介导的细胞摄取提供配体的 Tf-PEG-PEI（转铁蛋白-PEG-PEI）来生成复合物。在屏蔽缀合物中，不同大小（5、20 或 40 kDa）的 PEG 链与线性 PE122 (22 kDa) 或支链 PEI25 (25 kDa) 缀合。将三种聚合物成分以不同比例与 DNA 混合在一起；研究了颗粒大小、表面电荷、体外转染活性和向肿瘤的全身基因递送。一般来说，增加复合物中屏蔽缀合物的比例会降低富含转铁蛋白受体的 K562 细胞的表面电荷、颗粒大小和体外转染效率。含有PEG-PEI缀合物的复合物的粒径或表面电荷在冻融后没有显着变化，而不含屏蔽缀合物的复合物发生聚集。含有 PEG-PEI 缀合物的复合物在冻融后可有效转染 K562 细胞。此外，冻融复合物的全身应用表现出体内肿瘤靶向表达。对于含有荧光素酶报告基因的复合物，在小鼠肿瘤组织中发现最高表达。体内应用的最佳制剂 PEI22/Tf-PEG-PEI/PEI22-PEG5 含有编码肿瘤坏死因子 (TNF-α) 的质粒 DNA，在三种不同的小鼠肿瘤模型中抑制肿瘤生长。这些新的 DNA 复合物简单方便，冻融后具有体内肿瘤靶向活性。
Tumor-targeting DNA complexes which can readily be generated by the mixing of stable components and freeze-thawed would be very advantageous for their subsequent application as medical products. Complexes were generated by the mixing of plasmid DNA, linear polyethylenimine (PEI22, 22 kDa) as the main DNA condensing agent, PEG-PEI (poly(ethylene glycol)-conjugated PEI) for surface shielding, and Tf-PEG-PEI (transferrin-PEG-PEI) to provide a ligand for receptor-mediated cell uptake. Within the shielding conjugates, PEG chains of varying size (5, 20, or 40 kDa) were conjugated with either linear PE122 (22 kDa) or branched PEI25 (25 kDa). The three polymer components were mixed together at various ratios with DNA; particle size, surface charge, in vitro transfection activity, and systemic gene delivery to tumors was investigated. In general, increasing the proportion of shielding conjugate in the complex reduced surface charge, particle size, and in vitro transfection efficiency in transferrin receptor-rich K562 cells. The particle size or surface charge of the complexes containing the PEG-PEI conjugate did not significantly change after freeze-thawing, while complexes without the shielding conjugate aggregated. Complexes containing PEG-PEI conjugate efficiently transfected K562 cells after freeze-thawing. Furthermore the systemic application of freeze-thawed complexes exhibited in vivo tumor targeted expression. For complexes containing the luciferase reporter gene the highest expression was found in tumor tissue of mice. An optimum formulation for in vivo application, PEI22/Tf-PEG-PEI/PEI22-PEG5, containing plasmid DNA encoding for the tumor necrosis factor (TNF-alpha), inhibited tumor growth in three different murine tumor models. These new DNA complexes offer simplicity and convenience, with tumor targeting activity in vivo after freeze-thawing.