基于共培养技术的肿瘤微血管细胞模型的建立

目的 建立可研究肿瘤微血管的分子学特性及结构特性的细胞模型 ,应用于药物筛选及靶向药物输送的研究。方法 通过TRANSWELL共培养肿瘤细胞MCF 7和内皮细胞HUVEC的方法 ,建立肿瘤微血管细胞模型 ,检测了该模型下的细胞形态、结构、及通透性的变化。结果 在肿瘤细胞共生条件下的内皮细胞层结构疏松 ,微环境呈明显酸性 ,而且细胞间隙增大 ,对 10 0纳米左右粒子的通透性有显著提高。结论 这一细胞模型的建立将有助于肿瘤血管的分子、结构特性以及相关药物的筛选和输送研究。

Characterization and separation of DNA complexes containing poly-L-lysine with or without the modification of PEG by capillary electrophoresis

The characterization of complexes is particularly critical for quality control and development of gene delivery systems. Here, the method of capillary zone electrophoresis （CZE） for the characterization of DNA and polyoL-lysine （MW 28 500） or DNA and poly-L-lysine modified with polyethylene glycol （MW10 000） complexes at various charge ratios in phosphate buffer is described firstly. During the characterization, DNA complexes can be separated into various components with different charge-to-mass ratio, i.e, components with single physicochemical property. And also the size and zeta potential of complexes were characterized by using photon correlation spectroscopy. This method is useful to characterize various complexes formed by DNA and polycations, and has the potential to separate complexes into homogeneous component for better transfection efficiency in vitro and in vivo in future.