Characterization of cationic lipid-protamine-DNA (LPD) complexes for intravenous gene delivery
Characterization of cationic lipid-protamine-DNA (LPD) complexes for intravenous gene delivery
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DOI：
10.1038/sj.gt.3300683
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发表时间：
1998-07-01
期刊：
影响因子：
5.1
通讯作者：
Huang, L
中科院分区：
文献类型：
--
作者：
Li, S;Rizzo, MA;Huang, L
先前的研究已经显示，通过静脉内施用由DOTAP脂质体、硫酸鱼精蛋白和质粒DNA组成的LPD制剂，在小鼠中有效地全身性转基因表达。在本研究中，进一步评价了影响该制剂体内性能的因素。在加入质粒DNA之前将脂质体与鱼精蛋白混合的方案显示出产生直径约135 nm的小浓缩颗粒。这些颗粒随时间推移是稳定的，并在所有检查的组织中产生高水平的基因表达，包括肺、心脏、脾、肝和肾，其中在肺中的表达水平最高。包含二油酰磷脂酰乙醇胺（DOPE）作为辅助脂质显着降低LPD的体内活性。相反，胆固醇作为辅助脂质的加入增加了LPD的体内转染效率，更重要的是，减少了基因表达最大水平所需的阳离子脂质的量。对小鼠血清与LPD相互作用的研究表明，LPD在暴露于血清后带负电荷，并且含有不同辅助脂质的LPD在相关血清蛋白的量上不同。含有DOPE的LPD更富含分子量与白蛋白对应的蛋白质。这些结果表明，LPD介导的静脉内基因传递的机制可能不同于体外脂质体转染，血清蛋白结合可能是限制LPD体内转染的主要因素。
A previous study has shown an efficient, systemic transgene expression in mice via intravenous administration of a LPD formulation composed of DOTAP liposomes, protamine sulfate and plasmid DNA. In this study, factors affecting the in vivo performance of this formulation were further evaluated. A protocol in which liposomes were mixed with protamine before the addition of plasmid DNA was shown to produce small condensed particles with a diameter of about 135 nm. These particles were stable over time and gave a high level of gene expression in all tissues examined including lung, heart, spleen, liver and kidney with the highest level of expression in the lung. Inclusion of dioleoylphosphatidylethanolamine (DOPE) as a helper lipid significantly decreased the in vivo activity of LPD. In contrast inclusion of cholesterol as a helper lipid increased the in vivo transfection efficiency of LPD and more importantly, decrease the amount of cationic lipid required for the maximal level of gene expression. Studies on the interaction between mouse serum and LPD showed that LPD became negatively charged after exposure to serum, and LPDs containing different helper lipids varied in the amount of associated serum proteins. LPD containing DOPE was more enriched in a protein corresponding to albumin in molecular weight. These results suggest that the mechanism of LPD-mediated intravenous gene delivery might be different from that of in vitro lipofection and that serum protein association might be a major factor limiting the in vivo transfection by LPD.