Division of Molecular Pulmonology, Department of Pediatrics, Ludwig Maximilians University of Munich, Lindwurmstr. 2a, 80337 Munich, Germany.
Pharm Res. 2011 Sep;28(9):2223-32. doi: 10.1007/s11095-011-0464-z. Epub 2011 May 19.
Cationic polymers have been intensively investigated for plasmid-DNA (pDNA), but few studies addressed their use for messenger-RNA (mRNA) delivery. We analyzed two types of polymers, linear polyethylenimine (l-PEI) and poly-N,N-dimethylaminoethylmethacrylate P(DMAEMA), to highlight specific requirements for the design of mRNA delivery reagents. The effect of PEGylation was investigated using P(DMAEMA-co-OEGMA) copolymer.
The influence of polymer structure on mRNA binding and particle formation was assessed in a side-by-side comparison with pDNA by methods such as agarose-retardation assay and scanning probe microscopy. Transfection studies were performed on bronchial epithelial cells.
Binding of cationic polymers inversely correlated with type of nucleic acid. Whereas P(DMAEMA) bound strongly to pDNA, only weak mRNA binding was observed, which was vice versa for l-PEI. Both polymers resulted in self-assembled nanoparticles forming pDNA complexes of irregular round shape; mRNA particles were significantly smaller and more distinct. Surprisingly, PEGylation improved mRNA binding and transfection efficiency contrary to observations made with pDNA. Co-transfections with free polymer improved mRNA transfection.
Gene delivery requires tailor-made design for each type of nucleic acid. PEGylation influenced mRNA-polymer binding efficiency and transfection and may provide a method of further improving mRNA delivery.
阳离子聚合物已被广泛研究用于质粒 DNA（pDNA），但很少有研究涉及它们在信使 RNA（mRNA）传递中的应用。我们分析了两种类型的聚合物，线性聚乙烯亚胺（l-PEI）和聚 N,N-二甲基氨基乙基甲基丙烯酸酯 P（DMAEMA），以突出设计 mRNA 传递试剂的特定要求。使用聚（DMAEMA-co-OEGMA）共聚物研究了 PEG 化的效果。
通过琼脂糖阻滞实验和扫描探针显微镜等方法，对聚合物结构对 mRNA 结合和颗粒形成的影响进行了平行比较。在支气管上皮细胞上进行了转染研究。
阳离子聚合物与核酸类型的结合呈反比。虽然 P（DMAEMA）与 pDNA 结合强烈，但仅观察到弱的 mRNA 结合，而 l-PEI 则相反。两种聚合物都导致自组装纳米颗粒形成不规则圆形的 pDNA 复合物；mRNA 颗粒明显更小且更明显。令人惊讶的是，PEG 化改善了 mRNA 结合和转染效率，与 pDNA 的观察结果相反。与游离聚合物的共转染可改善 mRNA 转染。
基因传递需要针对每种类型的核酸进行定制设计。PEG 化影响 mRNA-聚合物结合效率和转染，并且可能提供进一步改善 mRNA 传递的方法。
