Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway.
Ultramicroscopy. 2010 May;110(6):689-93. doi: 10.1016/j.ultramic.2010.02.033. Epub 2010 Feb 23.
Immunostimulatory CpG-DNA activates the innate immune system by binding to Toll-like receptor 9. Structurally different CpG-containing oligonucleotides trigger a different type of immune response while activating the same receptor. We therefore investigated the higher order structure of two different classes of immunostimulatory CpG-DNA. Class A, which contains a partly self-complementary sequence and poly-G ends, forms duplexes and nanoparticles in salt solution, while class B, which does not contain these features and is purely linear, does not form a duplex or nanoparticles. Results obtained here by high-resolution atomic force microscopy of classes A and B CpG-DNA, reflect these differences in secondary structure. Detailed structural analysis of the atomic force microscopy topographs is presented for two different sample preparation methods.
免疫刺激型 CpG-DNA 通过与 Toll 样受体 9 结合来激活先天免疫系统。结构不同的含 CpG 寡核苷酸在激活相同受体的同时触发不同类型的免疫反应。因此，我们研究了两种不同类型的免疫刺激型 CpG-DNA 的高级结构。A 类含有部分自我互补序列和聚 G 末端，在盐溶液中形成双链体和纳米颗粒，而 B 类不含这些特征且为纯线性，不形成双链体或纳米颗粒。通过对 A 类和 B 类 CpG-DNA 的高分辨率原子力显微镜获得的结果反映了这些二级结构的差异。为两种不同的样品制备方法呈现了详细的原子力显微镜形貌结构分析。
