Analysis of hemagglutinin and neuraminidase gene characteristics of influenza B (Victoria) viruses isolated in Xi′an city from 2019 to 2023
10.3760/cma.j.cn112866-20240223-00025
- VernacularTitle:西安市2019—2023年分离的乙型Victoria系流感病毒血凝素和神经氨酸酶基因特征分析
- Author:
Yangni DENG
1
;
Peng ZHANG
;
Yujie YANG
;
Yuewen HAN
;
Yuanyuan DUAN
;
Shuling LI
;
Yinjuan HUANG
;
Jianing WEI
;
Ye ZHANG
;
Rui WU
;
Hailong CHEN
Author Information
1. 西安市疾病预防控制中心，西安 710054
- Keywords:
Influenza B virus;
Hemagglutinin;
Neuraminidase;
Phylogenic analysis
- From:
Chinese Journal of Experimental and Clinical Virology
2024;38(5):552-557
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the genetic and evolutionary characteristics of hemagglutinin (HA) and neuraminidase (NA) genes of influenza B/Victoria (BV) virus in Xi′an city from 2019 to 2023.Methods:Twenty-five BV strains isolated from the Xi′an influenza surveillance network laboratory between 2019 and 2023 were collected. The HA and NA genes were sequenced using MiniSeq high-throughput sequencing platform. An evolutionary tree was constructed using bioinformatics software to analyze homology and mutation sites, and to predict N-glycosylation sites online. The antigenicity of the strains was analyzed through hemagglutination inhibition tests.Results:The BV influenza in Xi′an exhibited a distinct seasonal transmission pattern from 2019 to 2023, with peak prevalence occurring during the winter and spring seasons. The evolutionary analysis of the HA genes shows that the strains from Xi′an in 2019 belong to the V1A.3 branch, and the strains from 2021 to 2023 belong to the V1A.3a.2 branch. Analysis of antigenic sites showed that there were variations in 6 sites of 3 antigenic determinants in the HA proteins of the BV strains from 2021-2022 compared to 2019, and 2 sites of 1 antigenic determinant changed in the HA proteins in 2023 compared to 2021-2022. The evolutionary analysis of the NA genes indicates that the BV strains from Xi′an in 2019 belong to the A. 1.1 branch. By 2021 and 2022, it had evolved into the A. 1.2 clade, and by 2023, it had further evolved into the B clade and its derivatives, with no strains showing mutations associated with resistance to NA inhibitors. Antigenic analysis indicated that the majority of BV strains in Xi′an were similar to the strains included in the vaccine composition. Furthermore, glycosylation analysis showed that the potential N-glycosylation sites in the HA proteins of BV strains from 2021-2023 were reduced by one compared to those from 2019, and only a few strains from 2023 displayed alterations in the potential N-glycosylation sites of the NA proteins.Conclusions:The HA and NA genes of the BV strains from 2019 to 2023 are continuously mutating and evolving into new branches. Since 2021, V1A.3a.2 has become the dominant evolutionary branch of the HA genes, while the evolutionary branches of the NA genes from 2019 to 2023 have been continuously changing.
