肿瘤靶向DNA载体转铁蛋白-多聚乙烯亚胺体外转染

目的评价转铁蛋白一多聚乙烯亚胺（Tf—PEI）靶向性转染小鼠骨肉瘤细胞的可行性。以Tf—PEI为载体，将小鼠白细胞介素（IL）-12基因导人小鼠骨肉瘤细胞。方法以Tf-PEI为载体，将绿色荧光蛋白基因和小鼠IL-12基因分别导人小鼠骨肉瘤细胞，并检测其转染效率。以游离转铁蛋白竞争性拮抗Tf-PEI，并观察它对转染效率的影响。结果Tf-PEI可以高效的、靶向性的转染小鼠骨肉瘤细胞。当N／P比值为5时，Tf-PEI的转染效率最高。游离转铁蛋白能够显著的拮抗Tf-PEI的转染。Tf-PEI还可以成功的将小鼠IL-12基因导人小鼠骨肉瘤细胞。结论 Tf—PEI是一种高效率、低毒性、肿瘤靶向性的基因转染载体，可以广泛应用于恶性肿瘤靶向性基因治疗的试验。

Transferrin-polythylenimine as a tumor-targeted vector for murine interleukin-12 gene transfer to the mouse osteosarcoma cells

Objective To investigate the feasibility and efficiency of transferrin-polyethylenimine (Tf-PEI) for tumor-targeted gene transfer to murine osteosarcoma. Using Tf-PEI as the vector,to transfer murine interleukin-12 (mIL-12) gene into mouse osteosarcoma cells. Methods Using Tf-PEI as the vector,murine osteosarcoma cells were transfected with plasmid DNA coding for murine IL-12 and green fluorescent protein (GFP),and the expression of the transduced gene was detected.By using free trans-ferrin to inhibit Tf-PEI,the influence on the transfection of Tf-PEI was observed. Results Tf-PEI could effectively and specifically deliver murine IL-12 gene and luciferase gene into murine osteosarcoma cells. When N/P ratio was 5 ,the transfection efficiency of Tf-PEI was highest. The transfection can be specifically inhibited by free transferrin. Conclusion Tf-PEI is a high efficiency and low cytotoxicity tumor-targeted vector. It can be widely used in the area of tumor-targeted gene therapy.