【摘要】 利用转铁蛋白受体介导的内吞作用,使转铁蛋白-阿霉素复合物(Tf-DOX)靶向作用于肿瘤细胞具有深远意义.文章利用荧光光谱确定了阿霉素对转铁蛋白具有荧光猝灭作用,且为静态猝灭.利用激光共聚焦显微镜观察到Tf-DOX可以靶向进入活的人肝癌细胞(HepG2)内,且5h时位于细胞质,24h时DOX解离进入细胞核.而同样条件,单独阿霉素5h已进入细胞核.利用流式细胞仪法检测了Tf-DOX进入细胞的转运机理,结果表明Tf-DOX是通过网格蛋白(Clathrin)介导、转铁蛋白受体决定的内吞机制进入细胞,具有温度、能量依赖性.体外培养条件下,利用MTT比色法检测Tf-DOX对HepG2细胞活力的影响,结果表明转铁蛋白-阿霉素体系保持较好的活性,相对单独阿霉素对细胞的杀伤力较强.这些结果表明转铁蛋白-阿霉素复合物具有明显的生物效应和潜在的生物医药价值.更多还原

【Abstract】 The transferrin-doxorubicin complex(Tf-DOX) targeted to the tumor cells have far-reaching significance by transferrin receptor-mediated endocytosis.It was determined that fluorescence quenching occurred when DOX acted on transferrin by means of the fluorescence spectra,and the quenching procedure is static quenching mechanism.Confocal fluorescence microscopy revealed that Tf-DOX system can efficiently delivery the drug inside living HepG cells,and were distributed in the cytoplasm for 5 hours and in the nucleolus for 24 hours.In contrast,free DOX could enter the nucleolus under the same condition.Ensemble-averaged measurements with fow cytometry indicate that the cellular uptake of Tf-DOX complex is a clathrin-mediated and transferrin-receptor dependent endocytosis,and has a temperature,the energy dependence.In vitro culture conditions,the use of MTT colorimetric assay showed that the Tf-DOX system maintains good biological activity,it implied that Tf-DOX complex has much strong cell lethality relative to doxorubicin alone.These results indicated that Tf-DOX has obvious biological effects and potential applications on biomedication.更多还原