National Nanotechnology Center, National Science and Technology Development Agency, Pathumthani, Thailand.
Carbohydr Polym. 2012 Oct 15;90(3):1323-9. doi: 10.1016/j.carbpol.2012.06.079. Epub 2012 Jul 6.
In this study, we examined the potential of cationic nanoparticle - polyethyleneimine-introduced chitosan shell/poly (methyl methacrylate) core nanoparticles (CS-PEI) for siRNA delivery. Initially, DNA delivery was performed to validate the capability of CS-PEI for gene delivery in the human cervical cancer cell line, SiHa. siRNA delivery were subsequently carried out to evaluate the silencing effect on targeted E6 and E7 oncogenes. Physicochemical properties including size, zeta potential and morphology of CS-PEI/DNA and CS-PEI/siRNA complexes, were analyzed. The surface charges and sizes of the complexes were observed at different N/P ratios. The hydrodynamic sizes of the CS-PEI/DNA and CS-PEI/siRNA were approximately 300-400 and 400-500nm, respectively. Complexes were positively charged depending on the amount of added CS-PEI. AFM images revealed the mono-dispersed and spherical shapes of the complexes. Gel retardation assay confirmed that CS-PEI nanoparticles completely formed complexes with DNA and siRNA at a N/P ratio of 1.6. For DNA transfection, CS-PEI provided the highest transfection result. Localization of siRNA delivered through CS-PEI was confirmed by differential interference contrast (DIC) confocal imaging. The silencing effect of siRNA specific to HPV 16 E6/E7 oncogene was examined at 18 and 24h post-transfection. The results demonstrated the capacity of CS-PEI to suppress the expression of HVP oncogenes.
在这项研究中，我们研究了阳离子纳米粒子-聚乙烯亚胺引入壳聚糖/聚（甲基丙烯酸甲酯）核纳米粒子（CS-PEI）在 siRNA 递送上的潜力。首先，进行 DNA 递送来验证 CS-PEI 在人宫颈癌 SiHa 细胞系中基因递送上的能力。随后进行 siRNA 递送来评估对靶向 E6 和 E7 癌基因的沉默效果。分析了包括 CS-PEI/DNA 和 CS-PEI/siRNA 复合物的大小、zeta 电位和形态在内的物理化学性质。观察了不同 N/P 比下复合物的表面电荷和大小。CS-PEI/DNA 和 CS-PEI/siRNA 的水动力粒径分别约为 300-400nm 和 400-500nm。复合物根据添加的 CS-PEI 的量带有正电荷。原子力显微镜图像显示了复合物的单分散和球形形状。凝胶阻滞实验证实 CS-PEI 纳米粒子在 N/P 比为 1.6 时完全与 DNA 和 siRNA 形成复合物。对于 DNA 转染，CS-PEI 提供了最高的转染效果。通过相差干涉对比（DIC）共焦成像证实了通过 CS-PEI 递送的 siRNA 的定位。转染后 18 和 24 小时检测了针对 HPV 16 E6/E7 癌基因的 siRNA 的沉默效果。结果表明 CS-PEI 具有抑制 HPV 癌基因表达的能力。
