Department of Cancer Biology , Dana-Farber Cancer Institute , Boston , Massachusetts 02215 , United States.
Wyss Institute for Biologically Inspired Engineering at Harvard , Boston , Massachusetts 02115 , United States.
J Am Chem Soc. 2020 Feb 19;142(7):3311-3315. doi: 10.1021/jacs.9b11698. Epub 2020 Feb 11.
DNA nanostructures (DNs) have garnered a large amount of interest as a potential therapeutic modality. However, DNs are prone to nuclease-mediated degradation and are unstable in low Mg conditions; this greatly limits their utility in physiological settings. Previously, PEGylated oligolysines were found to protect DNs against low-salt denaturation and to increase nuclease resistance by up to ∼400-fold. Here we demonstrate that glutaraldehyde cross-linking of PEGylated oligolysine-coated DNs extends survival by up to another ∼250-fold to >48 h during incubation with 2600 times the physiological concentration of DNase I. DNA origami with cross-linked oligolysine coats are non-toxic and are internalized into cells more readily than non-cross-linked origami. Our strategy provides an off-the-shelf and generalizable method for protecting DNs in vivo.
DNA 纳米结构 (DN) 作为一种潜在的治疗模式引起了广泛关注。然而，DN 易于被核酸酶介导降解，并且在低镁条件下不稳定；这极大地限制了它们在生理环境中的应用。先前发现聚乙二醇化寡聚赖氨酸可以保护 DNs 免受低盐变性，并将核酸酶抗性提高约 400 倍。在这里，我们证明聚乙二醇化寡聚赖氨酸涂层的 DNs 通过戊二醛交联，在与生理浓度的 DNase I 相比高达 2600 倍的浓度下孵育时，其存活时间延长了约 250 倍，超过 48 小时。具有交联寡聚赖氨酸涂层的 DNA 折纸结构无毒，并且比非交联的折纸结构更容易被细胞内化。我们的策略为在体内保护 DNs 提供了一种现成的、可推广的方法。
