Lipidoid Tail Structure Strongly Influences siRNA Delivery Activity
Lipidoid Tail Structure Strongly Influences siRNA Delivery Activity
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DOI：
10.1007/s12195-016-0436-9
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发表时间：
2016-09-01
影响因子：
2.8
通讯作者：
Whitehead, Kathryn A.
中科院分区：
文献类型：
--
作者：
Knapp, Christopher M.;Guo, Penghong;Whitehead, Kathryn A.
RNA干扰疗法在很大程度上受到缺乏有效、无毒、非免疫原性递送系统的限制。在先前建立的方法中，类脂纳米粒(LNPs)在体外和体内向不同的细胞和器官靶点传递siRNA方面显示出特别的前景。然而，需要更好地理解结构-功能关系，以促进广泛的临床应用。在这里，我们展示了尾部化学在赋予具有三个或四个脂肪族尾巴的类脂分子传递有效性方面的关键作用。尾巴的长度和结构对HeLa细胞中siRNA的转导有显著影响，甲基丙烯酸酯(与丙烯酸酯相比)的尾巴和含有醚的尾巴会导致效率降低。值得注意的是，我们报告了一种新的尾部前体--丙烯酸异癸酯，它在体外和体内都具有显著的siRNA递送能力。在体外和在小鼠(肝细胞)中，分别在40 nM和0.1 mg/kg剂量下，含有丙烯酸酯类脂类化合物的LNPs均能诱导90%以上的基因沉默。此外，我们发现尾部化学显著影响配方LNPs的表面pKa值，尾部提供更高的pKa促进更高水平的基因敲除。总之，这些数据强调了类脂尾部结构的重要性，并为下一代脂质纳米颗粒siRNA递送系统的开发提供了指导。
RNA interference therapeutics have been limited, in large part, by the lack of efficient, non-toxic, non-immunogenic delivery systems. Among previously established methods, lipidoid nanoparticles (LNPs) show particular promise in delivering siRNA to diverse cell and organ targets in vitro and in vivo. However, a better understanding of structure-function relationships is needed to facilitate broad translation to clinical applications. Here, we demonstrate the critical role of tail chemistry in conferring delivery efficacy to lipidoid molecules with three or four aliphatic tails. Tail length and structure significantly affected siRNA transfection in HeLa cells, with methacrylate (vs. acrylate) tails and tails containing ethers causing reductions in efficacy. Notably, we report a novel tail precursor, isodecyl acrylate, that conveyed marked siRNA delivery ability in vitro and in vivo. LNPs with isodecyl acrylate lipidoids uniformly induced greater than 90% gene silencing, both in vitro and in mice (hepatocytes), at 40 nM and 0.1 mg/kg, respectively. Furthermore, we found that tail chemistry significantly influenced the surface pKa values of formulated LNPs, with tails that conferred higher pKa facilitating higher levels of gene knockdown. Together, these data underscore the importance of lipidoid tail structure and provide guidance for the development of next generation lipid nanoparticle siRNA delivery systems.