Stahlschmidt Ullrich, Jérôme Valérie, Majewski Alexander P, Müller Axel H E, Freitag Ruth
Process Biotechnology, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany.
Evonik Resource Efficiency GmbH, Paul-Baumann-Straße 1, 45772 Marl, Germany.
Polymers (Basel). 2017 Apr 28;9(5):156. doi: 10.3390/polym9050156.
The introduction of the DNA into mammalian cells remains a challenge in gene delivery, particularly in vivo. Viral vectors are unmatched in their efficiency for gene delivery, but may trigger immune responses and cause severe side-reactions. Non-viral vectors are much less efficient. Recently, our group has suggested that a star-shaped structure improves and even transforms the gene delivery capability of synthetic polycations. In this contribution, this effect was systematically studied using a library of highly homogeneous, paramagnetic nano-star polycations with varied arm lengths and grafting densities. Gene delivery was conducted in CHO-K1 cells, using a plasmid encoding a green fluorescent reporter protein. Transfection efficiencies and cytotoxicities varied systematically with the nano-star architecture. The arm density was particularly important, with values of approximately 0.06 arms/nm² yielding the best results. In addition, a certain fraction of the cells became magnetic during transfection. The gene delivery potential of a nano-star and its ability to render the cells magnetic did not have any correlations. End-capping the polycation arms with di(ethylene glycol) methyl ether methacrylate (PDEGMA) significantly improved serum compatibility under transfection conditions; such nano-stars are potential candidates for future in vivo testing.
将DNA导入哺乳动物细胞在基因递送中仍然是一项挑战，尤其是在体内。病毒载体在基因递送效率方面无与伦比，但可能引发免疫反应并导致严重的副作用。非病毒载体的效率则低得多。最近，我们小组提出，星形结构可改善甚至转变合成聚阳离子的基因递送能力。在本论文中，使用了一系列具有不同臂长和接枝密度的高度均匀的顺磁性纳米星形聚阳离子，对这种效应进行了系统研究。在CHO-K1细胞中进行基因递送，使用编码绿色荧光报告蛋白的质粒。转染效率和细胞毒性随纳米星形结构而系统地变化。臂密度尤为重要，约0.06条臂/纳米²的值产生了最佳结果。此外，在转染过程中有一定比例的细胞变成了磁性。纳米星形的基因递送潜力与其使细胞产生磁性的能力没有任何关联。用甲基丙烯酸二（乙二醇）甲醚（PDEGMA）封端聚阳离子臂可显著提高转染条件下的血清相容性；此类纳米星形是未来体内测试的潜在候选物。
