Basic Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Oct 6, 2018; 6(11): 426-440
Published online Oct 6, 2018. doi: 10.12998/wjcc.v6.i11.426
Isolation and characterization of a new candidate human inactivated rotavirus vaccine strain from hospitalized children in Yunnan, China: 2010-2013
Jin-Yuan Wu, Yan Zhou, Guang-Ming Zhang, Guo-Fa Mu, Shan Yi, Na Yin, Yu-Ping Xie, Xiao-Chen Lin, Hong-Jun Li, Mao-Sheng Sun
Jin-Yuan Wu, Yan Zhou, Guang-Ming Zhang, Shan Yi, Na Yin, Yu-Ping Xie, Xiao-Chen Lin, Hong-Jun Li, Mao-Sheng Sun, Department of Molecular Biology, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Kunming 650118, Yunnan Province, China
Guo-Fa Mu, Pediatrics Department, the First People’s Hospital of Zhaotong City, Zhaotong 657000, Yunnan Province, China
Author contributions: Wu JY performed the majority of experiments and analyzed the data; Zhou Y, Zhang GM, Yi S, Mu GF, Yin N, Xie YP, and Lin XC performed the molecular investigations; Li HJ and Sun MS designed and coordinated the research; Wu JY and Zhou Y wrote the paper.
Supported by the CAMS Initiative for Innovative Medicine, No. 2016-I2M-1-019 and No. 2016-I2M-3-026; National Natural Science Foundation of China, No. 31700154; Major Science and Technology Special Project of Yunnan Province (Biomedicine), No. 2018ZF006; Science and Technology Project of Yunnan Province— general program, No. 2016FB034; and The State Project for Essential Drug Research and Development, the national “ Twelfth Five-Year” plan, No. 2014ZX09102041004.
Institutional review board statement: All experiments were approved by the Institutional Animal Care and Use Committee of Institute of Medical Biology, CAMS (Kunming, China).
Institutional animal care and use committee statement: All experiments were conducted in accordance with the ethical guidelines for animal experiments and safety guidelines.
Conflict-of-interest statement: The authors declare that they have no conflicts of interest.
ARRIVE guidelines statement: The manuscript was revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article, which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Hong-Jun Li, PhD, Full Professor, Department of Molecular Biology, Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, No. 935 Jiaoling Road, Kunming 650118, Yunnan Province, China. lihj6912@hotmail.com
Telephone: +86-138-8891-8945
Received: May 24, 2018
Peer-review started: May 24, 2018
First decision: July 3, 2018
Revised: July 16, 2018
Accepted: July 31, 2018
Article in press: August 2, 2018
Published online: October 6, 2018
Processing time: 127 Days and 8.5 Hours
ARTICLE HIGHLIGHTS
Research background

Human rotavirus genotypes G1-G4 and G9 are major causes of acute gastroenteritis in children worldwide. Approximately 35000 children die per year in China due to rotavirus, which is the second highest rate of rotavirus deaths in the world.

Research motivation

In China, the elimination and control of the two kinds of diseases have experienced the process of alternating use of two kinds of vaccines, which proved to be feasible and effective. These successful experiences provide a theoretical basis and an approach to the development of an inactivated rotavirus vaccine. This newly isolated human Group A rotavirus, ZTR-68 is being used to establish a new candidate inactivated rotavirus vaccine for use in studying the immune effectiveness.

Research objectives

The aim of this study was to determine the distribution of rotavirus VP7 gene in hospitalized children in Yunnan, China. A new candidate human inactivated rotavirus vaccine strain was isolated and characterized.

Research methods

A total of 366 stool specimens were collected from hospitalized children in hospitals in Yunnan Province from September 2010 to December 2013. The genomic RNA electropherotypes and the G genotypes of the rotaviruses were determined. A phylogenetic analysis of the VP7 genes was performed. Rotavirus isolation was performed, and characterized by plaque, EM, and all gene sequence analysis. The sequences were deposited in GenBank under the following accession numbers: KM247264 - KM247286. ZTR-68 genomic sequences: JX509930 - JX509940. Quantification of antibodies for inactivated vaccine prepared with ZTR-68 were examined by ELISA and microneutralization assay.

Research results

Group A human rotavirus was detected in 177 of 366 stool samples using a colloidal gold device assay. The temporal distribution of rotavirus cases showed significant correlation with the mean air temperature. Rotaviruses were isolated from 13% of the rotavirus-positive samples. The predominant genotype was G1 (43.5%), G3 (21.7%), G9 (17.4%), G2 (4.3%), G4 (8.7%), and mixed (4.3%). A rotavirus strain was isolated from a rotavirus-positive stool sample of a 4-month-old child in The First People’s Hospital of Zhaotong (2010) for use as a candidate human inactivated rotavirus vaccine strain and for further studies, which was designated ZTR-68. The genotype of 11 gene segments of strain ZTR-68 (RVA/Human-wt/CHN/ZTR-68/2010/G1P[8]) was characterized. The genotype constellation of strain ZTR-68 was identified as G1-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1. The VP7 and VP4 genotypes of strain ZTR-68 was similar to Wa-like strains.

Research conclusions

Group A human rotavirus was detected in 48.4% stool samples. A high prevalence of the G1, G2, and G3 genotypes was detected from 2010 to 2012. However, a dominant prevalence of the G9 genotype was identified as the cause of gastroenteritis in children in Yunnan, China, in 2013. A candidate human inactivated rotavirus vaccine strain, designated ZTR-68 was isolated, characterized, and showed immunogenicity.

Research perspectives

Our data will be useful for the future formulation and development of a vaccine in China.