Institut für Chemie und Biochemie, Freie Universität Berlin, Berlin, Germany.
Biomacromolecules. 2012 Oct 8;13(10):3087-98. doi: 10.1021/bm300892v. Epub 2012 Sep 7.
Development of nonviral vectors for the successful application of gene therapy through siRNA/DNA transfection of cells is still a great challenge in current research. (1, 2) In the present study, we have developed multivalent polyglycerol dendron based amphiphiles with well-defined molecular structures that express controlled glycine arrays on their surfaces. The structure-activity relationships with respect to the siRNA complexation, toxicity, and transfection profiles were studied with synthesized amphiphilic polycations. Our findings revealed that a second-generation amphiphilic dendrimer (G2-octaamine, 4) that has eight amine groups on its surface and a hydrophobic C-18 alkyl chain at the core of the dendron, acts as an efficient vector to deliver siRNA and achieve potent gene silencing by investigating the knockdown of luciferase and GAPDH gene activity in HeLa cells. Interestingly, the amphiphilic vector is nontoxic even at higher ratio of N/P 100. To the best of our knowledge this is the first example of successful in vitro siRNA transfection using dendritic amphiphiles. We believe that this supramolecular complex may serve as a new promising alternative for nonviral siRNA delivery systems and will be investigated for in vivo siRNA delivery in the future.
通过细胞的 siRNA/DNA 转染将基因治疗成功应用于非病毒载体的发展仍然是当前研究中的一个巨大挑战。(1,2) 在本研究中，我们开发了具有明确定义的分子结构的多价聚甘油树状大分子基于两亲性分子，其表面表达受控的甘氨酸阵列。用合成的两亲性聚阳离子研究了结构-活性关系，包括 siRNA 复合、毒性和转染特性。我们的研究结果表明，第二代两亲性树状大分子（G2-辛基胺，4）在其表面具有八个胺基团，在树突核心具有疏水 C-18 烷基链，作为一种有效的载体来传递 siRNA 并通过研究 HeLa 细胞中荧光素酶和 GAPDH 基因活性的敲低来实现有效的基因沉默。有趣的是，即使在更高的 N/P 比 100 下，两亲性载体也没有毒性。据我们所知，这是首次使用树枝状两亲物成功进行体外 siRNA 转染的实例。我们相信，这种超分子复合物可以作为一种有前途的非病毒 siRNA 传递系统的替代物，并将在未来用于体内 siRNA 传递的研究。
