摘要
目的了解西安市甲型流感病毒H3N2亚型血凝素基因特征及抗原变异情况。方法对2019年西安市分离到的流感毒株7株进行HA基因扩增及序列测定,同时获取WHO推荐的疫苗株HA基因序列,利用MEGA 6.0、BioEdit 7.2.5和NetNGlyc 1.0 Server在线分析软件对HA基因序列进行进化分析和抗原变异分析。结果 2019年3月西安市2株H3N2分离株的HA基因与2018—2019年疫苗株核苷酸序列同源性为98.7%~98.8%,与疫苗株相比共发生了13处氨基酸位点变异,其中位于E区的E78G变异发生在抗原决定簇,且未发生糖基化位点改变,10—11月5株H3N2分离株的HA基因与2019—2020年疫苗株核苷酸序列同源性为96.5%~96.8%,与疫苗株相比共发生了24个氨基酸位点变化,其中有6个发生在受体结合位点和抗原决定簇,分别为N137K、A144T、K160S、N187K、E78G、S153F,同时出现糖基化位点的增加或消失现象。结论 2019年上半年西安市H3N2流行株与WHO推荐2018—2019年疫苗株相比变异较少,下半年H3N2流行株与WHO推荐的2019—2020疫苗株匹配度程度降低,发生了抗原漂移现象,应加强流感病毒的分子变异监测。
Objective To understand the gene characteristics and antigenic variation of hemagglutinin in influenza A(H3N2) in Xi’an City. Methods HA gene of seven influenza strains isolated in Xi’an City in 2019 was amplified and sequenced, and the HA gene sequence of vaccine strains recommended by WHO was obtained. The evolution analysis and antigen variation analysis of HA gene sequence were carried out by MEGA 6.0, BioEdit 7.2.5 and NetNGlyc 1.0 Server online analysis software. Results The HA gene of two H3N2 isolates from Xi’an City in March 2019 had 98.7%-98.8% homology with the nucleotide sequence of the vaccine strains from 2018-2019. Compared with the vaccine strains, there were 13 amino acid site variations, among which the E78 G variation in E region occurred in the antigenic determinant cluster, and there was no glycosylation site change. The HA gene of five H3N2 isolates from October to November had 96.5%-96.8% homology with the nucleotide sequence of the vaccine strains from 2019-2020. Compared with the vaccine strain, there were 24 amino acid site changes, 6 of which occurred in receptor binding sites and antigenic determinants, including N137 K, A144 T, K160 S, N187 K, E78 G and S153 F, and glycosylation sites increased or disappeared at the same time. Conclusion In the first half of 2019, the H3N2 epidemic strain in Xi’an City had less variation compared with the vaccine strain recommended by WHO for 2018-2019. In the second half of 2019,the matching degree between H3N2 epidemic strain and the vaccine strain recommended by WHO for 2019-2020 was reduced,and antigen drift occurred. Therefore, the monitoring of influenza virus molecular variation should be strengthened.
作者
陈海龙
杨玉捷
邓杨妮
黄银娟
韩月雯
薛泽润
吴瑞
CHEN Hai-long;YANG Yu-jie;DENG Yang-ni;HUANG Yin-juan;HAN Yue-wen;XUE Ze-run;WU Rui(Department of Virology,Xi’an Center for Disease Control and Prevention,Xi'an Shaanxi,710054,China)
出处
《职业与健康》
CAS
2021年第5期607-610,共4页
Occupation and Health
