反义VEGF165腺病毒重组体的构建及鉴定

Construction and characterization of replication-deficient adenoviral vector containing the cDNA for human VEGF165 in an antisense orientation

目的 :构建含人反义血管内皮生长因子 16 5 (VEGF16 5 )基因的重组腺病毒载体 ,为采用反义VEGF16 5RNA防治肿瘤的研究奠定基础。方法 :将人VEGF16 5cDNA反向插入到穿梭质粒pHCMVSP1A的CMV启动子之下 ,即pAd -ahVEGF16 5。后者与pJM17通过脂质体共转染 2 93细胞 ,经同源重组获得含人反义VEGF16 5基因的重组腺病毒Ad -ahVEGF16 5。通过PCR共扩增法鉴别Ad -ahVEGF16 5的正确与否。根据 2 6 0nm的紫外光吸收值计算病毒滴度。结果 :VEGF16 5cDNA成功地反向插入了pHCMVSP1A载体 ,以重组病毒基因组DNA为模板 ,同时扩增出了5 76bp的反义VEGF16 5基因片段和 86 0bp的腺病毒骨架基因片段 ,证实了Ad -ahVEGF16 5的正确性。病毒滴度为5 .6× 10 11pfu/ml。结论 :成功构建了携带人反义VEGF16 5基因的腺病毒Ad -ahVEGF16 5 ,本研究为采用反义VEGFRNA途径治疗肿瘤的在体。

objective To construct the recombinant adenovirus vector containing the cDNA for hVEGF165 in an antisense orientation for future study of tumor treatment by antisense hVEGF165 RNA strategy.Methods The VEGF165 cDNA has been extracted from pUCCAGGS/hVEGF165 with EcoRI and then inserted in an antisense orientation into the E1-deleted expression plasmid pHCMVsp1A shuttle vector, called pAd-ahVEGF165. pAd-ahVEGF165 was cotransfected with the plasmid pJM17 into the transformed human embryonic kidney cell line 293 cells by liposome-mediated method. Homologous recombination of the pAd-ahVEGF165 and pJM17 in 293 cells replaced the E1 region with the expression cassette from pAd-ahVEGF165. Ad-ahVEGF165 was confirmed by PCR.Ad-ahVEGF165 was propagated in 293 cells and then underwent CsCl density purification. subsequently, the preparations were didalyzed in dialysis buffer. The titer of each viral stock was determined by measuring the absorbance at 260nm. Results VEGF165 cDNA was successfully inserted into the shuttle vector pHCMVSPIA. pAd-ahVEGF165 was confirmed by NcoI and XhoI digestion. Ad-ahVEGF165 was characterized by PCR coamplification. The virus titer was 5.6×10 11 pfu/ml. Conclusions Ad-ahVEGF165 containing the antisense VEGF165 sequence was successfully constructd.This investigation provides the basis for future study of tumor treatment based on antisense VEGF RNA strategy.