Synthesis and characterization of a head-tail type polycation block copolymer as a nonviral gene vector
Synthesis and characterization of a head-tail type polycation block copolymer as a nonviral gene vector
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DOI：
10.1021/bc0502863
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发表时间：
2006-01-01
影响因子：
4.7
通讯作者：
Kono, K
中科院分区：
文献类型：
--
作者：
Harada, A;Kawamura, M;Kono, K
本研究新设计了一种由聚酰胺胺（PAMAM）树枝和聚（L-赖氨酸）（PLL）嵌段组成的头尾型聚阳离子嵌段共聚物作为非病毒基因载体。这种嵌段共聚物（PAMAM dendron-PLL）的成功合成分两步：PAMAM dendron嵌段的合成和由PAMAM dendron嵌段聚合成PLL嵌段。嵌段共聚物中的PAMAM树枝状分子和PLL嵌段表现出独立的去质子化行为，并且它们的pK(a)分别测定为6.8和9.0。通过凝胶阻滞试验和染料排除试验评估了与pDNA的络合，两种试验都表明pDNA与嵌段共聚物的PLL段选择性地络合。此外，PAMAM dendron-PLL 聚合复合物对 HeLa 细胞的转染效率比 PLL 聚合复合物高 10(2) 倍。这可能是由于 PAMAM 树突块的缓冲作用。这种嵌段共聚物可以在每个嵌段中产生功能共享，即与pDNA复合的尾部嵌段和头部嵌段表现出缓冲作用。这种头尾型嵌段共聚物的分子设计可能为实现体内基因治疗提供新的途径。
A head-tail type polycation block copolymer, which is composed of the polyamidoamine (PAMAM) dendron and poly(L-lysine) (PLL) blocks, was newly designed as a nonviral gene vector in this study. This block copolymer (PAMAM dendron-PLL) was successfully synthesized in two steps: the synthesis of the PAMAM dendron block and the polymerization of the PLL block from the PAMAM dendron block. PAMAM dendron and PLL blocks in block copolymer showed independent deprotonation behavior, and their pK(a) were determined to be 6.8 and 9.0, respectively. The complexation with pDNA was evaluated by gel retardation assay and dye exclusion assay, and both assays indicated that pDNA was selectively complexed with PLL block of block copolymer. Also, the PAMAM dendron-PLL poplyplexes showed 10(2) fold higher transfection efficiency to HeLa cells as that for PLL polyplexes. This might be due to the buffering effect of the PAMAM dendron block. This block copolymer could produce a function share in each block, i.e., tail block complexed with pDNA and head block showed a buffering effect. This molecular design of the head-tail type block copolymer might provide a new approach for realizing in vivo gene therapy.