Contents lists available at ScienceDirect Antiviral Research journal homepage: www.elsevier.com/locate/antiviral Recombinant virus-like particle presenting a newly identified coxsackievirus A10 neutralization epitope induces protective immunity in mice Wenlong Dai a,1 , Pei Xiong a,1 , Xueyang Zhang a , Zhi Liu b , Jinhuan Chen c , Yu Zhou a , Xiaohua Ye a , Chao Zhang a,d,* a Vaccine Research Center, CAS Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China b Biological Imaging and Instrumental Analysis Center, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China c National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China d Joint Center for Infection and Immunity, Guangzhou Institute of Pediatrics, Department of Gastroenterology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China ARTICLE INFO Keywords: Coxsackievirus A10 Epitope Vaccine Virus-like particle Neutralization ABSTRACT Coxsackievirus A10 (CVA10) has emerged as one of the major pathogens of hand, foot, and mouth disease in recent years. However, there are no approved vaccines or effective drugs against CVA10. Several experimental CVA10 vaccines have been shown to elicit neutralizing antibodies that could confer protection against viral infection. However, neutralizing antigenic sites on CVA10 capsid have not been well characterized. Here, we report the characterization of linear neutralization epitopes of CVA10 and the development of a CVA10 vaccine based on the identified epitopes. We showed that peptide VP2-P28, corresponding to residues 136 to 150 of VP2, were recognized by anti-inactivated CVA10 sera and effectively inhibited anti-CVA10 sera-mediated neu- tralization, suggesting that this peptide contains neutralizing epitopes. Insertion of VP2-P28 into hepatitis B core antigen (HBc) resulted in a chimeric virus-like particle (VLP; designated HBc-P28) with the CVA10 epitope exposed on the particle surface. HBc-P28 VLP elicited strong antibody responses against VP2-P28 in mice. Anti- HBc-P28 sera could neutralize both CVA10 clinical isolates and prototype strain, consistent with the fact that the VP2-P28 sequence is highly conserved among CVA10 strains. In addition, anti-HBc-P28 sera failed to cross- neutralize other HFMD-causing enteroviruses, indicating that neutralizing antibodies elicited by HBc-P28 VLP were CVA10-specific. Importantly, anti-HBc-P28 sera were able to provide efficient protection against lethal CVA10 infection in recipient mice. Collectively, these data show that peptide VP2-P28 represents a CVA10- specific linear neutralizing antigenic site and chimeric VLP displaying this peptide is a promising epitope-based CVA10 vaccine candidate. 1. Introduction Hand, foot, and mouth disease (HFMD) is a common pediatric in- fectious disease that lead to significant morbidity and mortality worldwide, especially in the Asia-Pacific region (Repass et al., 2014; Ventarola et al., 2015). HFMD could be caused by a variety of en- teroviruses, including enterovirus 71 (EV71) and coxsackieviruses A16 (CVA16), A6 (CVA6), and A10 (CVA10) (Bian et al., 2015; Lu et al., 2012; Mao et al., 2014; Solomon et al., 2010; Wong et al., 2010). In particular, in recent years numerous HFMD cases and outbreaks have been reported to be associated with CVA10 infection (Chen et al., 2017; Ji et al., 2018; Munivenkatappa et al., 2018; Yang et al., 2015), thus indicating that CVA10 has emerged as one of the major causative agents of HFMD. Moreover, CVA10 co-circulated with CVA6, CVA16, and/or EV71 in several HFMD outbreaks (Blomqvist et al., 2010; Mirand et al., 2012; Wu et al., 2010), possibly resulting in viral co-infections and genetic recombination. CVA10 infections are generally mild and self- limiting, but severe life-threatening complications and even death can occur (Fuschino et al., 2012; Lu et al., 2012). CVA10 belongs to the A species of the Enterovirus genus within the https://doi.org/10.1016/j.antiviral.2019.02.016 Received 25 December 2018; Received in revised form 17 February 2019; Accepted 24 February 2019 * Corresponding author. Vaccine Research Center, CAS Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China. E-mail address: chaozhang@ips.ac.cn (C. Zhang). 1 These authors contributed equally: Wenlong Dai, Pei Xiong. Antiviral Research 164 (2019) 139–146 Available online 25 February 2019 0166-3542/ © 2019 Elsevier B.V. All rights reserved. T