Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai 201203, People's Republic of China.
Nanotechnology. 2010 Jul 2;21(26):265101. doi: 10.1088/0957-4484/21/26/265101. Epub 2010 Jun 4.
Dendrimers have attracted great interest in the field of gene delivery due to their synthetic controllability and excellent gene transfection efficiency. In this work, dendrigraft poly-L-lysines (DGLs) were evaluated as a novel gene vector for the first time. Derivatives of DGLs (generation 2 and 3) with different extents of PEGylation were successfully synthesized and used to compact pDNA as complexes. The result of gel retardation assay showed that pDNA could be effectively packed by all the vectors at a DGLs to pDNA weight ratio greater than 2. An increase in the PEGylation extent of vectors resulted in a decrease in the incorporation efficiency and cytotoxicity of complexes in 293 cells, which also decreased the zeta potential a little but did not affect the mean diameter of complexes. Higher generation of DGLs could mediate higher gene transfection in vitro. Confocal microscopy and cellular uptake inhibition studies demonstrated that caveolae-mediated process and macropinocytosis were involved in the cellular uptake of DGLs-based complexes. Also the results indicate that proper PEGylated DGLs could mediate efficient gene transfection, showing their potential as an alternate biodegradable vector in the field of nonviral gene delivery.
树状聚合物由于其合成可控性和优异的基因转染效率，在基因传递领域引起了极大的关注。在这项工作中，树状接枝聚赖氨酸（DGL）首次被评估为一种新型基因载体。成功合成了具有不同程度聚乙二醇化的 DGL 衍生物（第 2 代和第 3 代），并将其用于压缩 pDNA 形成复合物。凝胶阻滞实验结果表明，所有载体在 DGL 与 pDNA 的重量比大于 2 时都能有效地包裹 pDNA。载体的聚乙二醇化程度的增加导致复合物在 293 细胞中的掺入效率和细胞毒性降低，这也使 ζ 电位略有降低，但不影响复合物的平均直径。更高代的 DGL 可以介导更高的体外基因转染。共聚焦显微镜和细胞摄取抑制研究表明，小窝蛋白介导的过程和巨胞饮作用参与了 DGL 基复合物的细胞摄取。结果还表明，适当的聚乙二醇化 DGL 可以介导有效的基因转染，表明它们作为非病毒基因传递领域中替代的可生物降解载体具有潜力。
