A liposomal formulation comprising a dicationic cholesterol based lipid, Chol⁺-(CH₂)₅-Chol⁺, and a helper zwitterionic lipid, DOPE (1:4), was prepared to deliver polynucleotides of different topologies, molecular weights, and backbones. This formulation was used to transfect HeLa cells with circular and linearized plasmid pEGFP-C3. The transfection efficiency of the dicationic cholesterol based coliposomal formulation Chol⁺-(CH₂)₅-Chol⁺/DOPE (1:4) was observed to be better when compared against different commercial delivery agents, Lipofectamine2000, Effectene, and a known oligonucleotide delivery agent, Oligofectamine. The efficacy was also compared with the respective monocationic cholesterol based liposomal formulations. Western blot analysis for Smad2 protein detection showed almost 100% downregulation of the Smad2 protein by polynucleotides delivered by Chol⁺-(CH₂)₅-Chol⁺/DOPE (1:4), which was better than that with Oligofectamine and Effectene. Similarly, semiquantitative RT-PCR showed the downregulation of Smad2 RNA along with that of a downstream target of Smad2, Id2. The higher efficiency of different types of nucleic acid delivery was also evident with Chol⁺-(CH₂)₅-Chol⁺/DOPE (1:4) in A549 cells. As an added benefit, the formulation Chol⁺-(CH₂)₅-Chol⁺/DOPE (1:4) was found to be highly biocompatible at all the compositions investigated herein.

中文翻译：

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使用具有柔性间隔物的阳离子胆固醇二聚体打破 Smad2 反义治疗中多核苷酸大小、类型和拓扑的障碍

制备包含基于双阳离子胆固醇的脂质Chol ⁺ -(CH ₂ ) ₅ -Chol ⁺和辅助两性离子脂质DOPE (1:4)的脂质体制剂以递送不同拓扑结构、分子量和主链的多核苷酸。该制剂用于用环状和线性化质粒 pEGFP-C3 转染 HeLa 细胞。基于双阳离子胆固醇的共脂质体制剂Chol ⁺ -(CH ₂ ) ₅ -Chol ^{+的转染效率}当与不同的商业递送剂 Lipofectamine2000、Effectene 和已知的寡核苷酸递送剂 Oligofectamine 相比时，观察到 /DOPE (1:4) 更好。还将功效与各自的基于单阳离子胆固醇的脂质体制剂进行比较。用于 Smad2 蛋白检测的蛋白质印迹分析显示由 Chol ⁺ -(CH ₂ ) ₅ -Chol ^{+递送的多核苷酸几乎 100% 下调 Smad2 蛋白。}/DOPE (1:4)，优于 Oligofectamine 和 Effectene。类似地，半定量 RT-PCR 显示 Smad2 RNA 的下调以及 Smad2 的下游靶标 Id2 的下调。在 A549 细胞中使用 Chol ⁺ -(CH ₂ ) ₅ -Chol ⁺ /DOPE (1:4) 时，不同类型核酸递送的更高效率也很明显。作为额外的好处，发现制剂Chol ⁺ -(CH ₂ ) ₅ -Chol ⁺ /DOPE (1:4) 在本文研究的所有组合物中都具有高度的生物相容性。