Pavlova Anna S, Dovydenko Ilya S, Kupryushkin Maxim S, Grigor'eva Alina E, Pyshnaya Inna A, Pyshnyi Dmitrii V
Institute of Chemical Biology and Fundamental Medicine SB RAS, 630090 Novosibirsk, Russia.
Nanomaterials (Basel). 2020 Sep 29;10(10):1948. doi: 10.3390/nano10101948.
The conjugation of lipophilic groups to oligonucleotides is a promising approach for improving nucleic acid-based therapeutics' intracellular delivery. Lipid oligonucleotide conjugates can self-aggregate in aqueous solution, which gains much attention due to the formation of micellar particles suitable for cell endocytosis. Here, we describe self-association features of novel "like-a-brush" oligonucleotide conjugates bearing three dodecyl chains. The self-assembly of the conjugates into 30-170 nm micellar particles with a high tendency to aggregate was shown using dynamic light scattering (DLS), atomic force (AFM), and transmission electron (TEM) microscopies. Fluorescently labeled conjugates demonstrated significant quenching of fluorescence intensity (up to 90%) under micelle formation conditions. The conjugates possess increased binding affinity to serum albumin as compared with free oligonucleotides. The dodecyl oligonucleotide conjugate and its duplex efficiently internalized and accumulated into HepG2 cells' cytoplasm without any transfection agent. It was shown that the addition of serum albumin or fetal bovine serum to the medium decreased oligonucleotide uptake efficacy (by 22.5-36%) but did not completely inhibit cell penetration. The obtained results allow considering dodecyl-containing oligonucleotides as scaffold compounds for engineering nucleic acid delivery vehicles.
将亲脂性基团与寡核苷酸共轭是一种很有前景的方法，可用于改善基于核酸的治疗药物的细胞内递送。脂质寡核苷酸共轭物在水溶液中可自聚集，由于形成了适合细胞内吞作用的胶束颗粒，这一现象备受关注。在此，我们描述了带有三条十二烷基链的新型“刷状”寡核苷酸共轭物的自缔合特性。利用动态光散射（DLS）、原子力显微镜（AFM）和透射电子显微镜（TEM）观察到，共轭物自组装成30 - 170 nm的胶束颗粒，且具有很高的聚集倾向。荧光标记的共轭物在胶束形成条件下荧光强度显著猝灭（高达90%）。与游离寡核苷酸相比，共轭物与血清白蛋白的结合亲和力增加。十二烷基寡核苷酸共轭物及其双链体在没有任何转染剂的情况下能有效地内化并积累到HepG2细胞的细胞质中。结果表明，向培养基中添加血清白蛋白或胎牛血清会降低寡核苷酸的摄取效率（降低22.5 - 36%），但不会完全抑制细胞穿透。所得结果使我们可以将含十二烷基的寡核苷酸视为构建核酸递送载体的支架化合物。
