Wakebayashi Daisuke, Nishiyama Nobuhiro, Yamasaki Yuichi, Itaka Keiji, Kanayama Naoki, Harada Atsushi, Nagasaki Yukio, Kataoka Kazunori
Department of Materials Science and Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan.
J Control Release. 2004 Mar 24;95(3):653-64. doi: 10.1016/j.jconrel.2004.01.003.
alpha-Lactosyl-poly(ethylene glycol)-poly(2-(dimethylamino)ethyl methacrylate) block copolymer (lactose-PEG-PAMA) was synthesized to construct a PIC micellar-type gene vector potentially useful for selective transfection of hepatic cells. Lactose-PEG-PAMA spontaneously formed a polyion complex (PIC) micelle with plasmid DNA (pDNA) encoding luciferase (pGL3-Luc) in aqueous solution without any precipitate formation. The lactosylated PIC micelle thus prepared achieved substantially higher transfection efficiency compared to the control PIC micelle without lactose moieties against HepG2 cells possessing asialoglycoprotein (ASGP) receptors recognizing the beta-d-galactose residue. This pronounced transfection efficacy of the lactosylated PIC micelle was inhibited by the addition of excess asialofetuin (ASF), a natural ligand against the ASGP receptor, indicating ASGP receptor-mediated endocytosis to be a major route of the cellular uptake of the lactosylated micelles. Notably, the lactosylated PIC micelle revealed enhanced transfection compared to the control PIC micelle at a lower dose of pDNA, demonstrating the feasibility of using the ligand-conjugated PIC micellar vector for gene delivery to targeted cells.
合成了α-乳糖基-聚（乙二醇）-聚（甲基丙烯酸2-（二甲氨基）乙酯）嵌段共聚物（乳糖-聚乙二醇-聚甲基丙烯酸二甲氨基乙酯），以构建一种可能用于肝细胞选择性转染的聚离子复合物（PIC）胶束型基因载体。乳糖-聚乙二醇-聚甲基丙烯酸二甲氨基乙酯在水溶液中与编码荧光素酶的质粒DNA（pDNA）（pGL3-Luc）自发形成聚离子复合物（PIC）胶束，且无任何沉淀形成。与不含乳糖部分的对照PIC胶束相比，如此制备的乳糖化PIC胶束对具有识别β-d-半乳糖残基的去唾液酸糖蛋白（ASGP）受体的HepG2细胞实现了显著更高的转染效率。添加过量的去唾液酸胎球蛋白（ASF）（一种针对ASGP受体的天然配体）可抑制乳糖化PIC胶束的这种显著转染效果，表明ASGP受体介导的内吞作用是乳糖化胶束细胞摄取的主要途径。值得注意的是，在较低剂量的pDNA下，乳糖化PIC胶束与对照PIC胶束相比显示出增强的转染效果，证明了使用配体共轭的PIC胶束载体将基因递送至靶细胞的可行性。
