Synthesis and characterization of a novel arginine-grafted dendritic block copolymer for gene delivery and study of its cellular uptake pathway leading to transfection
Synthesis and characterization of a novel arginine-grafted dendritic block copolymer for gene delivery and study of its cellular uptake pathway leading to transfection
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DOI：
10.1021/bc0601525
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发表时间：
2007-03-01
影响因子：
4.7
通讯作者：
Park, Jong-sang
中科院分区：
文献类型：
--
作者：
Kim, Tae-il;Baek, Jung-un;Park, Jong-sang
我们合成了一种新型的用于基因传递系统的马来酸酐接枝树枝状嵌段共聚物R-PAMAM-PEG-PAMAM-RG 5（PPP 5-R）。通过MALDI-TOF测量其Mw为2.74 × 10（4）Da，并且通过H-1 NMR发现约36个精氨酸残基接枝到聚合物上。PPP 5-R能与质粒DNA形成平均大小约为200 nm的复合物。PPP 5-R复合物的正zeta电位值（+22至+28 mV）表明形成了带正电荷的稳定复合物颗粒，并表明即使在PEG包被的复合物形成后，具有高正电荷的大树枝状嵌段也可能未被PEG链完全屏蔽。PPP 5-R复合物由于聚合物的PEG核而显示出增强的水溶性，并且还显示出低细胞毒性，代表了体内应用的潜力。我们鉴定了PPP 5-R与天然PPP 5相比在各种细胞系上的转染效率大大增强。此外，考虑到转染步骤期间各种细胞摄取抑制剂处理的结果，认为导致有效转染的PPP 5-R多聚物的细胞摄取不依赖于一种排他性途径，并且具有多种途径（小窝-、网格蛋白-和巨胞饮介导的途径）的可能性，这与缺乏精氨酸残基的PPP 5多聚物的小窝-依赖性摄取相反。
We synthesized a novel arginine-grafted dendritic block copolymer, R-PAMAM-PEG-PAMAM-R G5 (PPP5-R) for gene delivery systems. Its Mw was measured as 2.74 x 10(4) Da by MALDI-TOF, and approximately 36 arginine residues are found to be grafted to the polymer by H-1 NMR. PPP5-R was able to form polyplexes with plasmid DNA, the average size of which was about 200 nm. Positive zeta-potential values (+22 to +28 mV) of PPP5-R polyplex indicate the formation of positively charged stable polyplex particles and suggest that large dendritic blocks with high positive charge may not be fully shielded by PEG chains even after PEG-coated complex formation. PPP5-R polyplex shows enhanced water solubility due to the polymer's PEG core and also shows low cytotoxicity, representing the potential for in vivo application. We identified the greatly enhanced transfection efficiency of PPP5-R in comparison with that of native PPP5 on various cell lines. Moreover, in view of the result of various cellular uptake inhibitor treatments during a transfection step, the cellular uptake of PPP5-R polyplex leading to effective transfection is thought to be not dependent on one exclusive pathway and to have the possibility of multiple pathways (caveolae-, clathrin-, and macropinocytosis-mediated pathways), contrary to the caveolae-dependent uptake of the PPP5 polyplex lacking arginine residues.