穿膜肽引导核酸靶向性进入神经细胞的研究

On a cell-penetrating peptide mediated targeted-delivery of DNA into neuronal cell

目的研究来源于狂犬病毒糖蛋白的一个新型衍生肽(RVG-derived peptide,RDP),是否能够引导DNA特异性地进入神经细胞。方法首先,通过琼脂糖凝胶电泳阻滞实验和圆二色谱确定RDP与DNA复合物的最佳比例以及相互作用,将最佳比例的复合物转染入神经母瘤细胞;其次,将RDP包裹的DNA复合物(RDP/pDNA)通过静脉给药的方式给予小鼠,组织冷冻切片检测DNA在各组织的表达情况。结果体外试验结果表明,目的基因仅在神经细胞中表达;体内试验结果表明,RDP/pDNA组小鼠的脑、肾、肝可检测到目的蛋白,其中脑内目的蛋白含量最高。结论 RDP可作为一种靶向神经细胞的基因载体,在未来的非病毒载体应用中可能具有较大的潜力。

Aim To investigate whether a novel peptide RDP,derived from rabies virus glycoprotein,has the ability of mediating targeted delivery of DNA into neuron cells. Methods Firstly,gel electrophoresis retardation assay and circular dichroism(CD) were used to analyze the interaction and optimal ratio of RDP and plasmid DNA. Subsequently,the optimal ratio of the RDP complex was transfected into the SHSY5Y cells for examination of specific protein expression,and then the complex of RDP/pDNA was intravenously injected into mice to determine the expression of the interest protein by cryostat sections and fluorescence microscopy. Results In vitro study results showed that the gene expression was only detected in the neuronal cells rather than non-neuronal cells. In vivo study results showed that the interest proteins were observed especially in the brain of RDP/pDNA-treated mice. Conclusions RDP could be used as an effective and convenient brain-targeting non-viral vector for gene therapy,which might display a great potential therapeutic application in the future.