Genetic variations in the fusion protein of respiratory syncytial virus isolated from children hospitalized with community-acquired pneumonia in China

Xiangpeng Chen,Li Deng,Yunlian Zhou,Yun Zhu,Zhou Fu,Zhengde Xie,Jiayun Guo,Lili Xu,Wei Wang,Aihuan Chen,Changchong Li,Shuhua An,Kunling Shen,Baoping Xu,Chunyan Liu

doi:10.1038/s41598-018-22826-4

Abstract

To identify the variations in fusion (F) protein gene of RSV in China, a molecular epidemiological study was conducted. A total of 553 RSV positive specimens were collected from 2338 pediatric patients hospitalized with community-acquired pneumonia during a multi-center study conducted during 2014–2016. A total of 252 samples (183 RSV A, 69 RSV B) were selected for F gene sequencing, and analyzed together with 142 F gene sequences downloaded from GenBank. The result showed that all the Chinese RSV A and RSV B strains could be divided respectively into three branches. Compared with RSV A/B prototype sequences respectively, there were significant amino acid (AA) mutations at multiple antigenic sites. For RSV A, changes were found at AA residues 122, 124, 125, 276 and 384, and for RSV B at AA residues 45, 116, 125, 172, 173 and 202. Variations in human histocompatibility leukocyte antigen-restricted CTL epitopes were also observed. In total, 56 amino acid differences for the complete F protein were found between the RSV A and B groups in China, while several mutations were only found in the RSV B strains during 2015–2016. The RSV F gene is relatively conserved in China, however, limited mutations are still occurring with time.

Highlights

Human respiratory syncytial virus (RSV) is a leading pathogen of acute lower respiratory tract infection (ALRTI) among young children[1,2]
A total of 553 (23.65%) RSV positive samples were identified from 2338 enrolled patients between November 2014 and June 2016 from 10 hospitals located in Beijing, Chongqing, Jilin, Hebei, Ningxia, Zhejiang, and Guangdong provinces in China
A total of 252 complete F gene sequences were obtained from 553 RSV positive samples, while the complete F gene sequences of 301 samples were not available because of poor sequence data quality

Summary

Introduction

Human respiratory syncytial virus (RSV) is a leading pathogen of acute lower respiratory tract infection (ALRTI) among young children[1,2]. RSV caused about 33.8 million new episodes of ALRTI worldwide in children younger than 5 years of age in 2005, which contained at least 3.4 (2.8–4.3) million severe cases necessitating hospital admission. Among these patients, there were roughly 66,000–199,000 deaths, with 99% of them occurring in developing countries[2]. The RSV fusion (F) protein is an important transmembrane glycoprotein which mediates the fusion between virus and the target cell membrane[6] It contains the main antigenic determinants associated with neutralizing antibodies and cytotoxic T-lymphocyte (CTL)-mediated immunity[7,8,9].

Methods

Results

Conclusion