Hou Wenxiu, Wei Ping, Kong Lingdan, Guo Rui, Wang Shige, Shi Xiangyang
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, People's Republic of China.
J Mater Chem B. 2016 May 7;4(17):2933-2943. doi: 10.1039/c6tb00710d. Epub 2016 Apr 18.
Exploring a plasmid DNA (pDNA)/small interfering RNA (siRNA) delivery vector with excellent biocompatibility and high gene transfection efficiency still remains a great challenge. In this research, generation 5 (G5) dendrimer-entrapped gold nanoparticles (Au DENPs) partially modified with polyethylene glycol monomethyl ether (mPEG) were designed as non-viral pDNA/siRNA delivery vectors. The pDNA that can encode luciferase (Luc) or enhanced green fluorescent protein (EGFP) and the Bcl-2 siRNA that can knockdown the expression of the Bcl-2 protein were successfully packaged by the partially PEGylated Au DENPs and effectively delivered into HeLa cells. The length of the surface conjugated mPEG chains and the composition of the entrapped Au NPs were systematically altered to explore their influences on the structure, cytotoxicity, and pDNA or siRNA delivery efficiency. We show that the modified mPEG and entrapped Au NPs can significantly improve the encoding of Luc and EGFP or silence the Bcl-2 protein expression, and the {(Au)-G5.NH-mPEG2K} DENPs display the best DNA or siRNA delivery efficiency among all the designed partially PEGylated Au DENPs. The Luc transfection efficiency of the {(Au)-G5.NH-mPEG2K} was about 292 times higher than that of the G5.NH dendrimers at an N/P ratio of 5 : 1, and the Bcl-2 protein was silenced to 15% using the {(Au)-G5.NH-mPEG2K} as a vector relative to the expression level transfected using the G5.NH dendrimers (100%). With enhanced pDNA/siRNA transfection efficiency and less cytotoxicity, the PEGylated Au DENPs may hold great promise to be used in pDNA and siRNA delivery applications.
探索一种具有优异生物相容性和高基因转染效率的质粒DNA（pDNA）/小干扰RNA（siRNA）递送载体仍然是一个巨大的挑战。在本研究中，设计了用聚乙二醇单甲醚（mPEG）部分修饰的第5代（G5）树枝状聚合物包裹的金纳米颗粒（Au DENPs）作为非病毒pDNA/siRNA递送载体。能够编码荧光素酶（Luc）或增强型绿色荧光蛋白（EGFP）的pDNA以及能够敲低Bcl-2蛋白表达的Bcl-2 siRNA被部分聚乙二醇化的Au DENPs成功包裹，并有效地递送至HeLa细胞中。系统地改变表面共轭mPEG链的长度和包裹的金纳米颗粒的组成，以探究它们对结构、细胞毒性以及pDNA或siRNA递送效率的影响。我们发现，修饰的mPEG和包裹的金纳米颗粒能够显著提高Luc和EGFP的编码效率或使Bcl-2蛋白表达沉默，并且{(Au)-G5.NH-mPEG2K} DENPs在所有设计的部分聚乙二醇化Au DENPs中表现出最佳的DNA或siRNA递送效率。在N/P比为5∶1时，{(Au)-G5.NH-mPEG2K}的Luc转染效率比G5.NH树枝状聚合物高约292倍，并且以{(Au)-G5.NH-mPEG2K}作为载体时，Bcl-2蛋白相对于使用G5.NH树枝状聚合物转染的表达水平（100%）被沉默至15%。由于提高了pDNA/siRNA转染效率且细胞毒性较小，聚乙二醇化的Au DENPs在pDNA和siRNA递送应用中可能具有巨大的应用前景。
