应用生物信息学方法预测H6亚型禽流感病毒血凝素蛋白(HA)线性抗原表位,并对所获表位的免疫原性进行初步鉴定,为流感病毒表位疫苗研制和H6亚型特异性ELISA检测方法奠定基础。依据近年流感病毒流行趋势,从G,enBank下载具有代表性的H6、H5、H7和H9亚型禽流感病毒血凝素蛋白的氨基酸序列。利用DNAStar软件进行H6同亚型间氨基酸序列保守性分析,再将H6与H5、H7、H9不同亚型之间氨基酸同源性进行比较,然后借助在线服务器ExPASy和IEDB对序列进行抗原性、亲水性、柔韧性、二级结构和表面可及性预测。最后去除H6与H5、H7、H9亚型氨基酸同源区域,选择H6亚型氨基酸相对保守区域并且抗原表位综合预测结果较优的几个片段,所选择表位长度为15个氨基酸。合成所获得的优势线性表位,并用间接ELISA方法对所获表位的免疫原性进行鉴定。预测后获得4个线性抗原表位,经鉴定免疫原性最好的为表位A,最差的为表位B。
The purpose of this study was to lay the foundation for developing an influenza virus epitope vac- cine and establishing an specific ELISA method of subtype H6 through the Prediction of H6 subtype avian influenza virus hemagglutinin(HA) protein linear epitopes by bioinformatics methods, and the preliminary identification of immunity of the antigen epitope. According to the recent trend of influenza virus, the repre- sentative H6, H5, H7and H9 subtype of avian influenza virus hemagglutinin protein amino acid sequences were downloaded from GenBank. The conservation of amino acid sequence of H6 subtypes was analyzedand the amino acid homology of H6 to H5, H7 and H9 was compared by DNAStar software, then the antigenicity, hydrophilicity,flexibility,secondary structure and surface accessibility of sequences were predicted by on-line Ex- PASy and IEDB server. Furthermore,after removal of the amino acid homology region of H6 and H5, H7 and H9 subtypes,several fragments (a length of 15 amino acids) were selected,which located in the relatively conservative region of H6 subtype, and had a better results of comprehensive linear epitope prediction in B-cell, and the synthesis of the obtained dominant B cell epitope and identification of the epitope immunogenicity by conventional indirect ELISA methods were performed. The prediction obtained four linear epitopes and all of them were found to have immunogenicity, hut epitope A is best and epitope B is worst.