Purpose: Nucleic acid-based therapies are a promising therapeutic tool. The major obstacle in their clinical translation is their efficient delivery to the desired tissue. We developed a novel nanosized delivery system composed of conjugates of α-tocopherol, polyethyleneimine, and polyethylene glycol (TPP) to deliver nucleic acids.
Methods: We synthesized a panel of TPP molecules using different molecular weights of PEG and PEI and analyzed with various analytical approaches. The optimized version of TPP (TPP₁₁₁ - the 1:1:1 molecular ratio) was self-assembled in water to produce nanostructures and then evaluated in diversified in vitro and in vivo studies.
Results: Through a panel of synthesized molecules, TPP₁₁₁ conjugate components self-assembled in water, forming globular shaped nanostructures of ∼ 90 nm, with high nucleic acid entrapment efficiency. The polymer had low cytotoxicity in vitro and protected nucleic acids from nucleases. Using a luciferase-expressing plasmid, TPP₁₁₁-plasmid nano-complexes were rapidly up-taken by cancer cells in vitro and induced strong transfection, comparable to PEI. Colocalization of the nano-complexes and endosomes/lysosomes suggested an endosome-mediated uptake. Using a subcutaneous tumor model, intravenously injected nano-complexes preferentially accumulated to the tumor area over 24 h.
Conclusion: These results indicate that we successfully synthesized the TPP₁₁₁ nanocarrier system, which can deliver nucleic acids in vitro and in vivo and merits further evaluation.

Keywords: nanoparticles, gene delivery, plasmid, tocopherol, polyethyleneimine, transfection


中文翻译：

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α-生育酚-聚乙烯亚胺-聚乙二醇纳米载体系统的核酸递送

目的：基于核酸的疗法是一种很有前途的治疗工具。它们临床转化的主要障碍是它们有效地传递到所需组织。我们开发了一种新型纳米递送系统，由α-生育酚、聚乙烯亚胺和聚乙二醇 (TPP) 的缀合物组成，用于递送核酸。
方法：我们使用不同分子量的 PEG 和 PEI 合成了一组 TPP 分子，并使用各种分析方法进行分析。TPP 的优化版本（TPP ₁₁₁ - 1:1:1 分子比）在水中自组装以产生纳米结构，然后在多种体外和体内研究中进行评估。
结果：通过一组合成分子，TPP ₁₁₁结合组分在水中自组装，形成~90 nm的球状纳米结构，具有高核酸包埋效率。该聚合物在体外具有低细胞毒性并保护核酸免受核酸酶的影响。使用荧光素酶表达质粒，TPP ₁₁₁质粒纳米复合物在体外被癌细胞迅速吸收并诱导强转染，与 PEI 相当。纳米复合物和内体/溶酶体的共定位表明内体介导的摄取。使用皮下肿瘤模型，静脉注射的纳米复合物在 24 小时内优先累积到肿瘤区域。
结论：这些结果表明我们成功合成了 TPP ₁₁₁纳米载体系统，可以在体外和体内传递核酸，值得进一步评估。

关键词：纳米颗粒，基因传递，质粒，生育酚，聚乙烯亚胺，转染