小鼠树突状细胞相关C型凝集素-1基因重组腺病毒载体的构建及鉴定

Construction and identification of a recombinant adenoviral vector expressing murine dendritic cell-associated C-type lectin-1

目的树突状细胞相关C型凝集素-1(dendritic cell-associated C-type lectin-1,Dectin-1)是介导抗真菌天然免疫的重要受体之一。文中旨在构建表达小鼠Dectin-1基因的重组腺病毒载体,扩增、纯化获得高浓度的重组腺病毒。方法将PCR扩增的目的片段CLEC7A-p IRES2-EGFP重组到中间载体p DONR221上,再与腺病毒骨架质粒p AD/CMV/V5-DEST重组,获得重组腺病毒质粒p AD-CLEC7A-p IRES2-EGFP,经Pac I线性化后转染人胚肾293(HEK293)细胞,收获重组腺病毒p AD-CLEC7A-p IRES2-EGFP;利用HEK293细胞大量扩增腺病毒;并进行重组腺病毒的滴度测定;用荧光显微镜和实时荧光定量PCR鉴定转染重组腺病毒组(Dectin-1基因重组腺病毒转染HEK293细胞)和转染空病毒组(空病毒转染HEK293细胞)中Dectin-1基因的表达。结果菌落PCR鉴定、酶切鉴定及测序结果均显示重组腺病毒含有Dectin-1基因,腺病毒滴度为5×1011IU/m L,荧光显微镜下可见绿色荧光,PCR检测到转染重组腺病毒组Dectin-1表达量是转染空病毒组的8677.25倍。结论成功构建并获得了较高浓度的Dectin-1基因重组腺病毒载体,为下一步体内外研究Dectin-1高表达在宿主抗真菌天然免疫中的作用奠定基础。

Objective Dendritic cell-associatedC-type lectin-1 （ Dectin-1） is one of the most important receptors in antifungal innate immune response.This study was to construct a recombinant adenovirus vector expressing themurine Dectin-1gene and acquire a high-concentration adenovirus by amplification and purification. Methods The PCR amplification product CLEC7A-pIRES2-EGFP was cloned into the intermediate vector pDONR221, and then recom-bined with the backbone vector pAD/CMV/V5-DEST to produce a re-combinant plasmid pAD-CLEC7A-pIRE2S -EGFP.The recombinant plasmid was linearized with Pac I and transfected into human embryon-ic kidney （ HEK293） cells to produce recombinant adenovirus pAD-CLEC7Ap-IRES 2-EGFP. The adenovirus was propagated in the HEK293 cells and purified by filtering through the cellulose acetate membrane and concentrating column.Fluorescence microscopy and re-al-time PCR were used to determine the expression of the Dectin-1 gene. Results PCR identification, enzyme digestion, and sequen-cing results manifested theDectin-1 gene in the vector, with the final adenovirus titer of 5＆#215;1011 IU/mL.Fluorescence microscopy revealed green fluorescence and real-time PCR assay confirmed that the expression of Dectin-1 was improved by 8677.25 times. Conclusion A relatively high-titer adenovirus expressing Dectin-1 was acquired,which may help to further study the high expression of Dectin-1 in anti-fungal innate immunity in vitro and in vivo.