Cheung C Y, Murthy N, Stayton P S, Hoffman A S
Department of Bioengineering, University of Washington, Seattle, Washington 98195, USA.
Bioconjug Chem. 2001 Nov-Dec;12(6):906-10. doi: 10.1021/bc0100408.
The efficient release of nonviral gene carriers from endosomes is an important step for the successful delivery of DNA into the cell nucleus. A synthetic pH-sensitive anionic polymer, poly(propylacrylic acid) (PPAA), was designed to aid in endosomal escape of nonviral vectors and improve the transfection efficiencies with these vectors. Transfection of NIH3T3 fibroblasts with ternary physical mixtures of the cationic lipid DOTAP, pCMVbeta plasmid DNA, and PPAA showed marked enhancement of both gene expression levels and fraction of cells transfected compared to binary control mixtures of DOTAP and DNA. PPAA also significantly improved the serum-stability of DOTAP/DNA vectors. The DOTAP/DNA/PPAA vectors maintained high levels of transfection in media containing up to 50% serum. The striking enhancement of transfection efficiency with cationic lipid/DNA/PPAA mixtures, along with the enhanced serum-stability, suggests that PPAA may provide significant improvements for the in vivo intracellular delivery of drugs such as DNA, oligonucleotides, proteins, and peptides.
非病毒基因载体从内体的有效释放是将DNA成功递送至细胞核的重要一步。设计了一种合成的pH敏感阴离子聚合物聚（丙烯酸丙酯）（PPAA），以帮助非病毒载体从内体逃逸，并提高这些载体的转染效率。与阳离子脂质DOTAP和DNA的二元对照混合物相比，用阳离子脂质DOTAP、pCMVbeta质粒DNA和PPAA的三元物理混合物转染NIH3T3成纤维细胞，基因表达水平和转染细胞比例均显著提高。PPAA还显著提高了DOTAP/DNA载体的血清稳定性。DOTAP/DNA/PPAA载体在含有高达50%血清的培养基中保持高水平的转染。阳离子脂质/DNA/PPAA混合物转染效率的显著提高以及血清稳定性的增强表明，PPAA可能为DNA、寡核苷酸、蛋白质和肽等药物的体内细胞内递送提供显著改善。
