Gene therapy aims to treat patients by altering or controlling gene expression. The field of gene therapy has had increasing success in recent years primarily using viral-based approaches; however, there is still significant interest toward the use of polymeric materials due to their potential as flexible, low-cost scaffolds for gene delivery that do not suffer the mutagenesis and immunogenicity concerns of viral vectors. To address the challenges of efficiency and biocompatibility, a series of zwitterion-like polyethylenimine derivatives (zPEIs) were produced via the succinylation of 2–11.5% of polyethylenimine (PEI) amines. With increasing modification, zPEI polyplexes exhibited decreased serum-protein aggregation and dissociated more easily in the presence of a competitor polyanion when compared to unmodified PEI. Surprisingly, the gene delivery mediated in the presence of serum showed that succinylation of as few as 2% of PEI amines resulted in transgene expression 260- to 480-fold higher than that of unmodified PEI and 50- to 65-fold higher than that of commercial PEI-PEG_2k in HEK293 and HeLa cells, respectively. Remarkably, the same zPEIs also produced 16-fold greater efficiency of CRISPR/Cas9 gene knock-in compared to unmodified PEI in the presence of serum. In addition, we show that 2% succinylation does not significantly decrease polymer/DNA binding ability or serum protein interaction to a significant extent, yet this small modification is still sufficient to provide a remarkable increase in transgene expression and gene knock-in in the presence of serum.

中文翻译：

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通过最小化琥珀酰化聚乙烯亚胺增强血清中的基因传递和 CRISPR/Cas9 同源定向修复

基因治疗旨在通过改变或控制基因表达来治疗患者。近年来，基因治疗领域取得了越来越大的成功，主要是使用基于病毒的方法；然而，由于聚合物材料具有作为基因传递的灵活、低成本支架的潜力，并且不受病毒载体的诱变和免疫原性问题的影响，因此人们仍然对使用聚合物材料产生了浓厚的兴趣。为了解决效率和生物相容性的挑战，通过 2-11.5% 的聚乙烯亚胺 (PEI) 胺的琥珀酰化生产了一系列两性离子样聚乙烯亚胺衍生物 (zPEI)。随着修饰的增加，与未修饰的 PEI 相比，zPEI 复合物表现出血清蛋白聚集减少，并且在存在竞争聚阴离子的情况下更容易解离。出奇，在 HEK293 和 HeLa 细胞中分别为_{2k 。}值得注意的是，与血清存在下未修饰的 PEI 相比，相同的 zPEI 的 CRISPR/Cas9 基因敲入效率也提高了 16 倍。此外，我们表明 2% 的琥珀酰化不会显着降低聚合物/DNA 结合能力或血清蛋白相互作用，但这种小的修饰仍然足以显着增加转基因表达和基因敲入。血清。