Transfection activity of binary mixtures of cationic o-substituted phosphatidylcholine derivatives: the hydrophobic core strongly modulates physical properties and DNA delivery efficacy.
Transfection activity of binary mixtures of cationic o-substituted phosphatidylcholine derivatives: the hydrophobic core strongly modulates physical properties and DNA delivery efficacy.
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DOI：
10.1529/biophysj.106.092700
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发表时间：
2006-11
影响因子：
3.4
通讯作者：
Li Wang;R. Koynova;Harsh Parikh;R. Macdonald
中科院分区：
文献类型：
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作者：
Li Wang;R. Koynova;Harsh Parikh;R. Macdonald
具有相同的头基但不同链长的尾的两种阳离子脂质衍生物的组合已显示出与单独的分子相比具有显著不同的转染活性。这些发现指出了研究阳离子两亲物疏水部分的重要性。因此，我们合成了多种具有不寻常疏水性部分的阳离子磷脂酰胆碱，并评估了它们的转染活性以及它们与此类原始分子二油酰-O-乙基磷脂酰胆碱（EDOPC）的混合物的转染活性。发现转染活性与混合物的组成之间存在四种不同的关系（绘制为添加到EDOPC中的新化合物的百分比），即：具有最大值或最小值;具有成比例的变化;或基本上没有变化。还检查了脂质复合物的相关物理性质;具体地，膜融合（通过阳离子和阴离子脂质之间的荧光共振能量转移）和DNA解结合（通过电泳和通过DNA和阳离子脂质之间的荧光共振能量转移测量为DNA对溴化乙锭的可及性），两者都是在添加带负电荷的膜脂质之后。无论转染模式如何，融合性随着第二阳离子脂质含量的增加而增加。然而，加入带负电荷的膜脂质后DNA解结合的程度确实与转染程度相关。阳离子脂质本身的相行为以及它们与膜脂质的混合物的相行为揭示了结构差异，这可能解释并支持膜脂质触发的、促进DNA释放的层状-->非层状相变对阳离子脂质的有效转染至关重要的假设。
A combination of two cationic lipid derivatives having the same headgroup but tails of different chain lengths has been shown to have considerably different transfection activity than do the separate molecules. Such findings point to the importance of investigating the hydrophobic portions of cationic amphiphiles. Hence, we have synthesized a variety of cationic phosphatidylcholines with unusual hydrophobic moieties and have evaluated their transfection activity and that of their mixtures with the original molecule of this class, dioleoyl-O-ethylphosphatidylcholine (EDOPC). Four distinct relationships between transfection activity and composition of the mixture (plotted as percent of the new compound added to EDOPC) were found, namely: with a maximum or minimum; with a proportional change; or with essentially no change. Relevant physical properties of the lipoplexes were also examined; specifically, membrane fusion (by fluorescence resonance energy transfer between cationic and anionic lipids) and DNA unbinding (measured as accessibility of DNA to ethidium bromide by electrophoresis and by fluorescence resonance energy transfer between DNA and cationic lipid), both after the addition of negatively charged membrane lipids. Fusibility increased with increasing content of second cationic lipid, regardless of the transfection pattern. However, the extent of DNA unbinding after addition of negatively charged membrane lipids did correlate with extent of transfection. The phase behavior of cationic lipids per se as well as that of their mixtures with membrane lipids revealed structural differences that may account for and support the hypothesis that a membrane lipid-triggered, lamellar-->nonlamellar phase transition that facilitates DNA release is critical to efficient transfection by cationic lipids.