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Arita M. An efficient trans complementation system for in vivo replication of defective poliovirus mutants. J Virol 2024; 98:e0052324. [PMID: 38837378 DOI: 10.1128/jvi.00523-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Accepted: 05/13/2024] [Indexed: 06/07/2024] Open
Abstract
The picornavirus genome encodes a large, single polyprotein that is processed by viral proteases to form an active replication complex. The replication complex is formed with the viral genome, host proteins, and viral proteins that are produced/translated directly from each of the viral genomes (viral proteins provided in cis). Efficient complementation in vivo of replication complex formation by viral proteins provided in trans, thus exogenous or ectopically expressed viral proteins, remains to be demonstrated. Here, we report an efficient trans complementation system for the replication of defective poliovirus (PV) mutants by a viral polyprotein precursor in HEK293 cells. Viral 3AB in the polyprotein, but not 2BC, was processed exclusively in cis. Replication of a defective PV replicon mutant, with a disrupted cleavage site for viral 3Cpro protease between 3Cpro and 3Dpol (3C/D[A/G] mutant) could be rescued by a viral polyprotein provided in trans. Only a defect of 3Dpol activity of the replicon could be rescued in trans; inactivating mutations in 2CATPase/hel, 3B, and 3Cpro of the replicon completely abrogated the trans-rescued replication. An intact N-terminus of the 3Cpro domain of the 3CDpro provided in trans was essential for the trans-active function. By using this trans complementation system, a high-titer defective PV pseudovirus (PVpv) (>107 infectious units per mL) could be produced with the defective mutants, whose replication was completely dependent on trans complementation. This work reveals potential roles of exogenous viral proteins in PV replication and offers insights into protein/protein interaction during picornavirus infection. IMPORTANCE Viral polyprotein processing is an elaborately controlled step by viral proteases encoded in the polyprotein; fully processed proteins and processing intermediates need to be correctly produced for replication, which can be detrimentally affected even by a small modification of the polyprotein. Purified/isolated viral proteins can retain their enzymatic activities required for viral replication, such as protease, helicase, polymerase, etc. However, when these proteins of picornavirus are exogenously provided (provided in trans) to the viral replication complex with a defective viral genome, replication is generally not rescued/complemented, suggesting the importance of viral proteins endogenously provided (provided in cis) to the replication complex. In this study, I discovered that only the viral polymerase activity of poliovirus (PV) (the typical member of picornavirus family) could be efficiently rescued by exogenously expressed viral proteins. The current study reveals potential roles for exogenous viral proteins in viral replication and offers insights into interactions during picornavirus infection.
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Affiliation(s)
- Minetaro Arita
- Department of Virology II, National Institute of Infectious Diseases, Musashimurayama-shi, Tokyo, Japan
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2
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Yan J, Wang M, Li X, Fan J, Yu R, Kang M, Zhang Y, Xu J, Zhang X, Zhang S. Construction of an infectious clone for enterovirus A89 and mutagenesis analysis of viral infection and cell binding. Microbiol Spectr 2024; 12:e0333223. [PMID: 38441464 PMCID: PMC10986554 DOI: 10.1128/spectrum.03332-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 01/29/2024] [Indexed: 04/06/2024] Open
Abstract
Enterovirus A89 (EV-A89) is an unconventional strain belonging to the Enterovirus A species. Limited research has been conducted on EV-A89, leaving its biological and pathogenic properties unclear. Developing reverse genetic tools for EV-A89 would help to unravel its infection mechanisms and aid in the development of vaccines and anti-viral drugs. In this study, an infectious clone for EV-A89 was successfully constructed and recombinant enterovirus A89 (rEV-A89) was generated. The rEV-A89 exhibited similar characteristics such as growth curve, plaque morphology, and dsRNA expression with parental strain. Four amino acid substitutions were identified in the EV-A89 capsid, which were found to enhance viral infection. Mechanistic studies revealed that these substitutions increased the virus's cell-binding ability. Establishing reverse genetic tools for EV-A89 will significantly contribute to understanding viral infection and developing anti-viral strategies.IMPORTANCEEnterovirus A species contain many human pathogens and have been classified into conventional cluster and unconventional cluster. Most of the research focuses on various conventional members, while understanding of the life cycle and infection characteristics of unconventional viruses is still very limited. In our study, we constructed the infectious cDNA clone and single-round infectious particles for the unconventional EV-A89, allowing us to investigate the biological properties of recombinant viruses. Moreover, we identified key amino acids residues that facilitate EV-A89 infection and elucidate their roles in enhancing viral binding to host cells. The establishment of the reverse genetics system will greatly facilitate future study on the life cycle of EV-A89 and contribute to the development of prophylactic vaccines and anti-viral drugs.
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Affiliation(s)
- Jingjing Yan
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Min Wang
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Xiaohong Li
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Jun Fan
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Rui Yu
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Miaomiao Kang
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Yong Zhang
- WHO WPRO Regional Polio Reference Laboratory, National Health Commission Key Laboratory for Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Jianqing Xu
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Xiaoyan Zhang
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Shuye Zhang
- Clinical Center for Biotherapy, Zhongshan Hospital, Fudan University, Shanghai, China
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Zang L, Yang X, Chen Y, Huang F, Yuan Y, Chen X, Zuo Y, Miao Y, Gu J, Guo H, Xia W, Peng Y, Tang M, Huang Z, Wang Y, Ma J, Jiang J, Zhou W, Zheng H, Shi W. Ubiquitin E3 ligase SPOP is a host negative regulator of enterovirus 71-encoded 2A protease. J Virol 2023; 97:e0078623. [PMID: 37796126 PMCID: PMC10617436 DOI: 10.1128/jvi.00786-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 08/25/2023] [Indexed: 10/06/2023] Open
Abstract
IMPORTANCE EV71 poses a significant health threat to children aged 5 and below. The process of EV71 infection and replication is predominantly influenced by ubiquitination modifications. Our previous findings indicate that EV71 prompts the activation of host deubiquitinating enzymes, thereby impeding the host interferon signaling pathway as a means of evading the immune response. Nevertheless, the precise mechanisms by which the host employs ubiquitination modifications to hinder EV71 infection remain unclear. The present study demonstrated that the nonstructural protein 2Apro, which is encoded by EV71, exhibits ubiquitination and degradation mediated by the host E3 ubiquitin ligase SPOP. In addition, it is the first report, to our knowledge, that SPOP is involved in the host antiviral response.
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Affiliation(s)
- Lichao Zang
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
- Department of Clinical Laboratory, The First Affiliated Hospital of Ningbo University, Ningbo First Hospital, Ningbo, Zhejiang, China
| | - Xinyu Yang
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Yan Chen
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Fan Huang
- International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou, Jiangsu, China
- Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, Jiangsu, China
| | - Yukang Yuan
- International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou, Jiangsu, China
- Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, Jiangsu, China
| | - Xiangjie Chen
- International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou, Jiangsu, China
- Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, Jiangsu, China
| | - Yibo Zuo
- International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou, Jiangsu, China
- Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, Jiangsu, China
| | - Ying Miao
- International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou, Jiangsu, China
- Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, Jiangsu, China
| | - Jin Gu
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Hui Guo
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Wenxin Xia
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Yang Peng
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Mengyuan Tang
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Ziwei Huang
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Yangyang Wang
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Jinhong Ma
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Jingting Jiang
- Department of Tumor Biological Treatment, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Wei Zhou
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
| | - Hui Zheng
- International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou, Jiangsu, China
- Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, Jiangsu, China
| | - Weifeng Shi
- Department of Laboratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China
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Weng KF, Tee HK, Tseligka ED, Cagno V, Mathez G, Rosset S, Nagamine CM, Sarnow P, Kirkegaard K, Tapparel C. Variant enterovirus A71 found in immune-suppressed patient binds to heparan sulfate and exhibits neurotropism in B-cell-depleted mice. Cell Rep 2023; 42:112389. [PMID: 37058406 PMCID: PMC10590055 DOI: 10.1016/j.celrep.2023.112389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 01/30/2023] [Accepted: 03/29/2023] [Indexed: 04/15/2023] Open
Abstract
Enterovirus A71 (EV-A71) causes hand, foot, and mouth disease outbreaks with neurological complications and deaths. We previously isolated an EV-A71 variant in the stool, cerebrospinal fluid, and blood of an immunocompromised patient who had a leucine-to-arginine substitution on the VP1 capsid protein, resulting in increased heparin sulfate binding. We show here that this mutation increases the virus's pathogenicity in orally infected mice with depleted B cells, which mimics the patient's immune status, and increases susceptibility to neutralizing antibodies. However, a double mutant with even greater heparin sulfate affinity is not pathogenic, suggesting that increased heparin sulfate affinity may trap virions in peripheral tissues and reduce neurovirulence. This research sheds light on the increased pathogenicity of variant with heparin sulfate (HS)-binding ability in individuals with decreased B cell immunity.
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Affiliation(s)
- Kuo-Feng Weng
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Han Kang Tee
- Department of Microbiology and Molecular Medicine, University of Geneva Medical School, Geneva, Switzerland
| | - Eirini D Tseligka
- Department of Microbiology and Molecular Medicine, University of Geneva Medical School, Geneva, Switzerland
| | - Valeria Cagno
- Department of Microbiology and Molecular Medicine, University of Geneva Medical School, Geneva, Switzerland
| | - Gregory Mathez
- Department of Microbiology and Molecular Medicine, University of Geneva Medical School, Geneva, Switzerland
| | - Stéphane Rosset
- Department of Microbiology and Molecular Medicine, University of Geneva Medical School, Geneva, Switzerland
| | - Claude M Nagamine
- Department of Comparative Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Peter Sarnow
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Karla Kirkegaard
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Caroline Tapparel
- Department of Microbiology and Molecular Medicine, University of Geneva Medical School, Geneva, Switzerland.
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Xie J, Hu X, Li H, Zhu H, Lin W, Li L, Wang J, Song H, Jia L. Murine models of neonatal susceptibility to a clinical strain of enterovirus A71. Virus Res 2023; 324:199038. [PMID: 36599394 DOI: 10.1016/j.virusres.2022.199038] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 12/11/2022] [Accepted: 12/31/2022] [Indexed: 01/02/2023]
Abstract
Enterovirus A71 (EV-A71) is neurotropic and one of the primary enteric pathogens responsible for severe central nervous system infection in infants and young children. Neonatal mice are ideal models for studying the pathogenesis of infection caused by EV-A71. In this study, we assessed the susceptibility of neonatal BALB/c, C57BL/6, ICR, Kunming, and NIH mice to a clinically isolated EV-A71 strain. One-day-old mice were challenged with a clinical isolate of EV-A71 via intraperitoneal injection, then observed for 13 days for mortality, body-weight changes, and limb paralysis. RT-qPCR was performed to quantify viral RNA in the brain, spinal cord, skeletal muscle, and lungs of BALB/c and C57BL/6 mice. The expression of murine scavenger receptor class B member 2 (mSCARB2) was measured by western blotting. Finally, lesions were assessed by histological examination. We found that neonatal BALB/c and C57BL/6 mice were both susceptible to EV-A71, leading to decreased survival rate, greater body weight loss, and prominent hind-limb paralysis. Tissue viral loads of C57BL/6J mice were markedly higher than those of BALB/c mice, indicating that EV-A71 replicated more efficiently in C57BL/6 mice. Increased expression of mSCARB2 was observed 5 days after infection in C57BL/6 mice, which coincided with the peak in EV-A71 replication. Histological examination indicated that infection caused obvious pathogenic lesions. In conclusion, C57BL/6 are most susceptible to infection caused by EV-A71 and can be used as a model for studying its pathogenesis and test therapeutic options.
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Affiliation(s)
- Jing Xie
- Center for Disease Control and Prevention of PLA, Beijing, China
| | - Xinyan Hu
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Anhui, China; Center for Disease Control and Prevention of PLA, Beijing, China
| | - Huan Li
- Center for Disease Control and Prevention of PLA, Beijing, China
| | - Hongwei Zhu
- Department of Orthopedic Surgery, Fourth center of Chinese PLA General Hospital, Beijing, China
| | - Weishi Lin
- Center for Disease Control and Prevention of PLA, Beijing, China
| | - Lizhong Li
- Center for Disease Control and Prevention of PLA, Beijing, China
| | - Ji Wang
- Chinese Center for Disease Controls and Prevention, Beijing, China
| | - Hongbin Song
- Center for Disease Control and Prevention of PLA, Beijing, China.
| | - Leili Jia
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Anhui, China; Center for Disease Control and Prevention of PLA, Beijing, China.
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Cheng D, Chiu YW, Huang SW, Lien YY, Chang CL, Tsai HP, Wang YF, Wang JR. Genetic and Cross Neutralization Analyses of Coxsackievirus A16 Circulating in Taiwan from 1998 to 2021 Suggest Dominant Genotype B1 can Serve as Vaccine Candidate. Viruses 2022; 14:2306. [PMID: 36298861 PMCID: PMC9608817 DOI: 10.3390/v14102306] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/15/2022] [Accepted: 10/18/2022] [Indexed: 07/30/2023] Open
Abstract
Coxsackievirus A16 (CVA16) is well known for causing hand-foot-and-mouth disease (HFMD) and outbreaks were frequently reported in Taiwan in the past twenty years. The epidemiology and genetic variations of CVA16 in Taiwan from 1998 to 2021 were analyzed in this study. CVA16 infections usually occurred in early summer and early winter, and showed increased incidence in 1998, 2000-2003, 2005, 2007-2008, and 2010 in Taiwan. Little or no CVA16 was detected from 2017 to 2021. CVA16 infection was prevalent in patients between 1 to 3 years old. A total of 69 isolates were sequenced. Phylogenetic analysis based on the VP1 region showed that CVA16 subgenotype B1 was dominantly isolated in Taiwan from 1998 to 2019, and B2 was identified only from isolates collected in 1999 and 2000. There was a high frequency of synonymous mutations in the amino acid sequences of the VP1 region among CVA16 isolates, with the exception of position 145 which showed positive selection. The recombination analysis of the whole genome of CVA16 isolates indicated that the 5'-untranslated region and the non-structural protein region of CVA16 subgenotype B1 were recombined with Coxsackievirus A4 (CVA4) and enterovirus A71 (EVA71) genotype A, respectively. The recombination pattern of subgenotype B2 was similar to B1, however, the 3D region was similar to EVA71 genotype B. Cross-neutralization among CVA16 showed that mouse antisera from various subgenotypes viruses can cross-neutralize different genotype with high neutralizing antibody titers. These results suggest that the dominant CVA16 genotype B1 can serve as a vaccine candidate for CVA16.
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Affiliation(s)
- Dayna Cheng
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
| | - Yo-Wei Chiu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan 70101, Taiwan
| | - Sheng-Wen Huang
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Tainan 70101, Taiwan
| | - Yun-Yin Lien
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan 70101, Taiwan
| | - Chia-Lun Chang
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan 70101, Taiwan
| | - Huey-Pin Tsai
- Department of Pathology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
| | - Ya-Fang Wang
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan 70101, Taiwan
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Tainan 70101, Taiwan
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
| | - Jen-Ren Wang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan 70101, Taiwan
- Department of Pathology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
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Swain SK, Gadnayak A, Mohanty JN, Sarangi R, Das J. Does enterovirus 71 urge for effective vaccine control strategies? Challenges and current opinion. Rev Med Virol 2022; 32:e2322. [PMID: 34997684 DOI: 10.1002/rmv.2322] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 12/21/2021] [Accepted: 12/23/2021] [Indexed: 12/17/2022]
Abstract
Enterovirus 71 (EV71) is an infectious virus affecting all age groups of people around the world. It is one of the major aetiologic agents for HFMD (hand, foot and mouth disease) identified globally. It has led to many outbreaks and epidemics in Asian countries. Infection caused by this virus that can lead to serious psychological problems, heart diseases and respiratory issues in children younger than 10 years of age. Many studies are being carried out on the pathogenesis of the virus, but little is known. The host immune response and other molecular responses against the virus are also not clearly determined. This review deals with the interaction between the host and the EV71 virus. We discuss how the virus makes use of its proteins to affect the host's immunity and how the viral proteins help their replication. Additionally, we describe other useful resources that enable the virus to evade the host's immune responses. The knowledge of the viral structure and its interactions with host cells has led to the discovery of various drug targets for the treatment of the virus. Additionally, this review focusses on the antiviral drugs and vaccines developed by targeting various viral surface molecules during their infectious period. Furthermore, it is asserted that the improvement of prevailing vaccines will be the simplest method to manage EV71 infection swiftly. Therefore, we summarise numerous vaccines candidate for the EV71, such as the use of an inactivated complete virus, recombinant VP1 protein, artificial peptides, VLPs (viral-like particles) and live attenuated vaccines for combating the viral outbreaks promptly.
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Affiliation(s)
- Subrat Kumar Swain
- Centre for Genomics and Biomedical Informatics, IMS and SUM Hospital, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, India
| | - Ayushman Gadnayak
- Centre for Genomics and Biomedical Informatics, IMS and SUM Hospital, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, India
| | - Jatindra Nath Mohanty
- Centre for Genomics and Biomedical Informatics, IMS and SUM Hospital, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, India
| | - Rachita Sarangi
- Department of Pediatrics, IMS and SUM Hospital, Siksha 'O' Anusandhan University (Deemed to be University), Bhubaneswar, India
| | - Jayashankar Das
- Centre for Genomics and Biomedical Informatics, IMS and SUM Hospital, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, India
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High-Order Epistasis and Functional Coupling of Infection Steps Drive Virus Evolution toward Independence from a Host Pathway. Microbiol Spectr 2021; 9:e0080021. [PMID: 34468191 PMCID: PMC8557862 DOI: 10.1128/spectrum.00800-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The phosphatidylinositol-4 kinase IIIβ (PI4KB)/oxysterol-binding protein (OSBP) family I pathway serves as an essential host pathway for the formation of viral replication complex for viral plus-strand RNA synthesis; however, poliovirus (PV) could evolve toward substantial independence from this host pathway with four mutations. Recessive epistasis of the two mutations (3A-R54W and 2B-F17L) is essential for viral RNA replication. Quantitative analysis of effects of the other two mutations (2B-Q20H and 2C-M187V) on each step of infection reveals functional couplings between viral replication, growth, and spread conferred by the 2B-Q20H mutation, while no enhancing effect was conferred by the 2C-M187V mutation. The effects of the 2B-Q20H mutation occur only via another recessive epistasis between the 3A-R54W/2B-F17L mutations. These mutations confer enhanced replication in PI4KB/OSBP-independent infection concomitantly with an increased ratio of viral plus-strand RNA to the minus-strand RNA. This work reveals the essential roles of the functional coupling and high-order, multi-tiered recessive epistasis in viral evolution toward independence from an obligatory host pathway. IMPORTANCE Each virus has a different strategy for its replication, which requires different host factors. Enterovirus, a model RNA virus, requires host factors PI4KB and OSBP, which form an obligatory functional axis to support viral replication. In an experimental evolution system in vitro, virus mutants that do not depend on these host factors could arise only with four mutations. The two mutations (3A-R54W and 2B-F17L) are required for the replication but are not sufficient to support efficient infection. Another mutation (2B-Q20H) is essential for efficient spread of the virus. The order of introduction of the mutations in the viral genome is essential (known as “epistasis”), and functional couplings of infection steps (i.e., viral replication, growth, and spread) have substantial roles to show the effects of the 2B-Q20H mutation. These observations would provide novel insights into an evolutionary pathway of the virus to require host factors for infection.
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Adaptation and Virulence of Enterovirus-A71. Viruses 2021; 13:v13081661. [PMID: 34452525 PMCID: PMC8402912 DOI: 10.3390/v13081661] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/18/2021] [Accepted: 08/19/2021] [Indexed: 12/19/2022] Open
Abstract
Outbreaks of hand, foot, and mouth disease caused by enterovirus-A71 (EV-A71) can result in many deaths, due to central nervous system complications. Outbreaks with many fatalities have occurred sporadically in the Asia-Pacific region and have become a serious public health concern. It is hypothesized that virulent mutations in the EV-A71 genome cause these occasional outbreaks. Analysis of EV-A71 neurovirulence determinants is important, but there are no virulence determinants that are widely accepted among researchers. This is because most studies have been done in artificially infected mouse models and because EV-A71 mutates very quickly to adapt to the artificial host environment. Although EV-A71 uses multiple receptors for infection, it is clear that adaptation-related mutations alter the binding specificity of the receptors and allow the virus to adopt the best entry route for each environment. Such mutations have confused interpretations of virulence in animal models. This article will discuss how environment-adapted mutations in EV-A71 occur, how they affect virulence, and how such mutations can be avoided. We also discuss future perspectives for EV-A71 virulence research.
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Abstract
Hand, Foot and Mouth Disease (HFMD) is usually a self-limiting, mild childhood disease that is caused mainly by Coxsackie virus A16 (CVA16) and Enterovirus A71 (EV-A71), both members of the Picornaviridae family. However, recurring HFMD outbreaks and epidemics due to EV-A71 infection in the Western Pacific region, and the propensity of EV-A71 strains to cause severe neurological complications have made this neurotropic virus a serious public health concern in afflicted countries. High mutation rate leading to viral quasispecies combined with frequent intra- and inter-typic recombination events amongst co-circulating EV-A71 strains have contributed to the great diversity and fast evolution of EV-A71 genomes, making impossible any accurate prediction of the next epidemic strain. Comparative genome sequence analyses and mutagenesis approaches have led to the identification of a number of viral determinants involved in EV-A71 fitness and virulence. These viral determinants include amino acid residues located in the structural proteins of the virus, affecting attachment to the host cell surface, receptor binding, and uncoating events. Critical residues in non-structural proteins have also been identified, including 2C, 3A, 3C proteases and the RNA-dependent RNA polymerase. Finally, mutations altering key secondary structures in the 5’ untranslated region were also found to influence EV-A71 fitness and virulence. While our current understanding of EV-A71 pathogenesis remains fragmented, these studies may help in the rational design of effective treatments and broadly protective vaccine candidates.
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Affiliation(s)
- Pei Yi Ang
- Infectious Diseases Translational Research Programme, Department of Microbiology&Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Immunology programme, Life Sciences Institute, Centre for Life Sciences, National University of Singapore, 28 Medical Drive, Singapore 117456, Singapore
| | - Connie Wan Hui Chong
- Infectious Diseases Translational Research Programme, Department of Microbiology&Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Immunology programme, Life Sciences Institute, Centre for Life Sciences, National University of Singapore, 28 Medical Drive, Singapore 117456, Singapore
| | - Sylvie Alonso
- Infectious Diseases Translational Research Programme, Department of Microbiology&Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Immunology programme, Life Sciences Institute, Centre for Life Sciences, National University of Singapore, 28 Medical Drive, Singapore 117456, Singapore
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Safety and Immunogenicity of a Stable, Cold-Adapted, Temperature-Sensitive/Conditional Lethal Enterovirus A71 in Monkey Study. Viruses 2021; 13:v13030438. [PMID: 33803356 PMCID: PMC8001754 DOI: 10.3390/v13030438] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/05/2021] [Accepted: 03/05/2021] [Indexed: 12/27/2022] Open
Abstract
Enterovirus A71 (EV-A71) and coxsackievirus A16 (CA16) are major etiological agents of hand foot and mouth disease (HFMD) in children, which may result in fatal neurological complications. The development of safe, cost effective vaccines against HFMD, especially for use in developing countries, is still a top public health priority. We have successfully generated a stable, cold-adapted, temperature sensitive/conditional lethal EV-A71 through adaptive culturing in Vero cells at incrementally lower cultivation temperatures. An additional 40 passages at an incubation temperature of 28 °C, and a temperature reversion study at an incubation temperature of 37 °C and 39.5 °C, reveals the virus’s phenotypic and genetic stability at the predefined culture conditions. Six unique mutations (two in noncoding regions and four in nonstructural protein-coding genes) in combination may have contributed to its stable phenotype and inability to fully revert to its original wild phenotype. The safety and immunogenicity of this stable, cold-adapted, temperature sensitive/conditional lethal EV-A71 was performed in six monkeys. None of the inoculated monkeys developed any obvious clinical illness except one which developed a transient spike of fever. No gross postmortem lesion or abnormal histological finding was noted for all monkeys at autopsy. No virus was reisolated although EV-A71 specific RNA was detected in serum samples collected on both day 4 and day 8 postinoculation. Only EV-A71 RNA and viral antigen were detected in the spleen homogenate and peripheral blood mononuclear cells, respectively, collected on day 4. The two remaining monkeys developed good humoral immune response on day 14 and day 30 post-inoculation.
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Zhang G, Hu B, Huo Y, Lu J, Guo J, Deng M, Li P, Wang W, Li L, Meng S, Wang Z, Shen S. Amino acid substitutions in VP2, VP1, and 2C attenuate a Coxsackievirus A16 in mice. Microb Pathog 2020; 150:104603. [PMID: 33271234 DOI: 10.1016/j.micpath.2020.104603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 09/21/2020] [Accepted: 10/30/2020] [Indexed: 11/29/2022]
Abstract
Coxsackievirus A16 (CVA16) is one of the major etiological agents of hand, foot and mouth disease (HFMD), a common acute infectious disease affecting infants and young children. Severe symptoms of the central nervous system may develop and even lead to death. Here, a plaque-purified CVA16 strain, L731-P1 (P1), was serially passaged in Vero cells for six times and passage 6 (P6) stock became highly attenuated in newborn mice. Genomic sequencing of the P1 and P6 revealed seven nucleotide substitutions at positions 1434 (C to U), 2744 (A to G), 2747 (A to G), 3161 (G to A), 3182 (A to G), 4968 (C to U), and 6064 (C to U). Six of these substitutions resulted in amino acid changes at VP2-T161 M, VP1-N102D, VP1-T103A, VP1-E241K, VP1-T248A, and 2C-S297F, respectively. P1-based infectious cDNA was generated to further investigate these virulent determinants. Independent reverse transcription-polymerase chain reaction (RT-PCR) amplifications for mutant constructions and plaque-purification of the P6 for isolation of variants were performed to determine dominant mutations and strains more related to attenuation. The virulent P1, attenuated P6, as well as a plaque purified strain (PP) and other four recombinant mutants, were inoculated into one-day-old BALB/c mice and the 50% lethal dose of each strain was determined. Comparison of virulence among these strains indicated that amino acid changes of VP1-N102D, VP1-E241K and 2C-S297F might be associated more closely with a high level attenuation of CVA16-L731-P6 than other mutations. Identification of novel residues associated with virulence may contribute to understanding of molecular basis of virulence of CVA16 and other enteroviruses.
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Affiliation(s)
- Gaobo Zhang
- Wuhan Huaxia University of Technology, Wuhan, 430223, China.
| | - Bing Hu
- Hubei Provincial Center for Disease Control and Prevention, Wuhan, 430000, China
| | - Yuqi Huo
- The Sixth People' s Hospital of Zhengzhou, Zhengzhou, 450000, China
| | - Jia Lu
- Laboratory of Viral Vaccine Research, Wuhan Institute of Biological Products (WIBP) Co. Ltd., Wuhan, 430207, China
| | - Jing Guo
- Laboratory of Viral Vaccine Research, Wuhan Institute of Biological Products (WIBP) Co. Ltd., Wuhan, 430207, China
| | - Mi Deng
- Worldwide Safety and Regulatory Pfizer, Inc., Wuhan, 430000, China
| | - Pengfei Li
- Laboratory of Viral Vaccine Research, Wuhan Institute of Biological Products (WIBP) Co. Ltd., Wuhan, 430207, China
| | - Weishan Wang
- Laboratory of Viral Vaccine Research, Wuhan Institute of Biological Products (WIBP) Co. Ltd., Wuhan, 430207, China
| | - Li Li
- Laboratory of Viral Vaccine Research, Wuhan Institute of Biological Products (WIBP) Co. Ltd., Wuhan, 430207, China
| | - Shengli Meng
- Laboratory of Viral Vaccine Research, Wuhan Institute of Biological Products (WIBP) Co. Ltd., Wuhan, 430207, China
| | - Zejun Wang
- Laboratory of Viral Vaccine Research, Wuhan Institute of Biological Products (WIBP) Co. Ltd., Wuhan, 430207, China.
| | - Shuo Shen
- Laboratory of Viral Vaccine Research, Wuhan Institute of Biological Products (WIBP) Co. Ltd., Wuhan, 430207, China.
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Arita M, Fuchino H, Kawakami H, Ezaki M, Kawahara N. Characterization of a New Antienterovirus D68 Compound Purified from Avocado. ACS Infect Dis 2020; 6:2291-2300. [PMID: 32567833 DOI: 10.1021/acsinfecdis.0c00404] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
One of the major challenges in development of antienterovirus (EV) drugs is in the safety of the drug. Here, we attempted to identify anti-EV compounds from an edible plant extract library and found potent antienterovirus D68 (EV-D68) activity in avocado (Persea americana). The purified identity is determined as 2R,4R-(12Z,15Z)-heneicosa-12,15-diene-1,2,4-triol, named avoenin. Avoenin shows an EC50 of 2.0 μM for EV-D68 (Fermon) infection with CC50 of >150 μM in RD cells by targeting the uncoating step of EV-D68 infection. Resistant mutations of EV-D68 (VP3-V24I, S173P, and S180G) to avoenin confer cross-resistance to pleconaril, an uncoating inhibitor of EV-D68. The inhibitory effect of avoenin is substantially specific to EV-D68 among the EVs. This work reveals avoenin as the identity of anti-EV-D68 activity in avocado and offers insights into development of a novel and effective strategy to overcome EV-D68 infection and its related respiratory diseases.
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Affiliation(s)
- Minetaro Arita
- Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-murayama, Tokyo 208-0011, Japan
| | - Hiroyuki Fuchino
- Research Center for Medicinal Plant Resources, National Institutes of Biomedical Innovation, Health and Nutrition, 1-2 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan
| | - Hitomi Kawakami
- Research Center for Medicinal Plant Resources, National Institutes of Biomedical Innovation, Health and Nutrition, 1-2 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan
| | - Masami Ezaki
- Research Center for Medicinal Plant Resources, National Institutes of Biomedical Innovation, Health and Nutrition, 1-2 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan
| | - Nobuo Kawahara
- Research Center for Medicinal Plant Resources, National Institutes of Biomedical Innovation, Health and Nutrition, 1-2 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan
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14
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Heparan sulfate attachment receptor is a major selection factor for attenuated enterovirus 71 mutants during cell culture adaptation. PLoS Pathog 2020; 16:e1008428. [PMID: 32187235 PMCID: PMC7105141 DOI: 10.1371/journal.ppat.1008428] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 03/30/2020] [Accepted: 02/23/2020] [Indexed: 02/06/2023] Open
Abstract
Enterovirus 71 (EV71) is a causative agent of hand, foot, and mouth disease (HFMD). However, this infection is sometimes associated with severe neurological complications. Identification of neurovirulence determinants is important to understand the pathogenesis of EV71. One of the problems in evaluating EV71 virulence is that its genome sequence changes rapidly during replication in cultured cells. The factors that induce rapid mutations in the EV71 genome in cultured cells are unclear. Here, we illustrate the population dynamics during adaptation to RD-A cells using EV71 strains isolated from HFMD patients. We identified a reproducible amino acid substitution from glutamic acid (E) to glycine (G) or glutamine (Q) in residue 145 of the VP1 protein (VP1-145) after adaptation to RD-A cells, which was associated with attenuation in human scavenger receptor B2 transgenic (hSCARB2 tg) mice. Because previous reports demonstrated that VP1-145G and Q mutants efficiently infect cultured cells by binding to heparan sulfate (HS), we hypothesized that HS expressed on the cell surface is a major factor for this selection. Supporting this hypothesis, selection of the VP1-145 mutant was prevented by depletion of HS and overexpression of hSCARB2 in RD-A cells. In addition, this mutation promotes the acquisition of secondary amino acid substitutions at various positions of the EV71 capsid to increase its fitness in cultured cells. These results indicate that attachment receptors, especially HS, are important factors for selection of VP1-145 mutants and subsequent capsid mutations. Moreover, we offer an efficient method for isolation and propagation of EV71 virulent strains with minimal selection pressure for attenuation. Viruses must overcome various setbacks in a variety of tissues and cells during transmission from the initial replication site to the final target site. To achieve this, RNA viruses employ a strategy to adapt to different environments by creating a diverse viral population using low-fidelity RNA-dependent RNA polymerases. On the other hand, when the viruses are propagated in clonal cell cultures, in vitro adaptation occurs. The viruses may acquire new properties or lose some properties they had in vivo. In vitro adaptation is often associated with attenuation. Therefore, the selection pressures imposed on viruses replicating in vitro and in vivo are quite different. It is unclear how this environmental difference affects viral populations. Clinical isolates of EV71 replicate in cultured cells poorly. However, after a few passages, the viruses adapt to this condition and replicate efficiently. In this study, we demonstrate that attachment receptor usage is a major selection pressure for in vitro adaptation of EV71 by analyzing the population dynamics of cell culture-adapted viruses. This mechanism appears to be a major mode of attenuation.
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15
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Chen BS, Lee HC, Lee KM, Gong YN, Shih SR. Enterovirus and Encephalitis. Front Microbiol 2020; 11:261. [PMID: 32153545 PMCID: PMC7044131 DOI: 10.3389/fmicb.2020.00261] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/04/2020] [Indexed: 12/24/2022] Open
Abstract
Enterovirus-induced infection of the central nervous system (CNS) results in acute inflammation of the brain (encephalitis) and constitutes a significant global burden to human health. These viruses are thought to be highly cytolytic, therefore normal brain function could be greatly compromised following enteroviral infection of the CNS. A further layer of complexity is added by evidence showing that some enteroviruses may establish a persistent infection within the CNS and eventually lead to pathogenesis of certain neurodegenerative disorders. Interestingly, enterovirus encephalitis is particularly common among young children, suggesting a potential causal link between the development of the neuroimmune system and enteroviral neuroinvasion. Although the CNS involvement in enterovirus infections is a relatively rare complication, it represents a serious underlying cause of mortality. Here we review a selection of enteroviruses that infect the CNS and discuss recent advances in the characterization of these enteroviruses with regard to their routes of CNS infection, tropism, virulence, and immune responses.
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Affiliation(s)
- Bo-Shiun Chen
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Hou-Chen Lee
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Kuo-Ming Lee
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Nong Gong
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Laboratory Medicine, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Shin-Ru Shih
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Laboratory Medicine, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan.,Research Center for Food and Cosmetic Safety, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan.,Graduate Institute of Health Industry Technology, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan
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16
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Wang CR. Pathogenesis of hand-foot-mouth disease caused by enterovirus 71. Shijie Huaren Xiaohua Zazhi 2019; 27:1465-1472. [DOI: 10.11569/wcjd.v27.i24.1465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hand-foot-mouth disease (HFMD) is a global infectious disease. The infected population is mainly infants and young children. Enterovirus 71 (EV71) is the main pathogen. In addition to HFMD, EV71 infection can also affect the nervous system and other organs, resulting in aseptic meningitis, brainstem encephalitis, and poliomyelitis-like paralysis, causing serious harm to children's health. At present, the pathogenesis of HFMD caused by EV71 is still unclear, and there is no effective treatment. In this paper, we discuss the factors influencing EV71 infection from the aspects of virus gene recombination and spontaneous mutation, host genes, and receptor sites, review the pathogenesis of HFMD caused by EV71 based on the study findings from animal infection models, and explore the main problems in the study of pathogenesis of this condition, in order to provide reference for the prevention and treatment of HFMD and for the development of new drugs or effective vaccines for EV71 infection.
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Affiliation(s)
- Chun-Rong Wang
- Institute for Viral Disease Detection, Jinan Center for Disease Control and Prevention, Jinan 250021, Shandong Province, China
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17
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Reverse Genetic Analysis of Adaptive Mutations within the Capsid Proteins of Enterovirus 71 (EV-A71) Strains Necessary for Infection of CHO-K1 Cells. Virol Sin 2019; 35:110-114. [PMID: 31637630 DOI: 10.1007/s12250-019-00167-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 08/30/2019] [Indexed: 10/25/2022] Open
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18
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Huang SW, Cheng D, Wang JR. Enterovirus A71: virulence, antigenicity, and genetic evolution over the years. J Biomed Sci 2019; 26:81. [PMID: 31630680 PMCID: PMC6802317 DOI: 10.1186/s12929-019-0574-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 10/01/2019] [Indexed: 01/06/2023] Open
Abstract
As a neurotropic virus, enterovirus A71 (EV-A71) emerge and remerge in the Asia-Pacific region since the 1990s, and has continuously been a threat to global public health, especially in children. Annually, EV-A71 results in hand-foot-and-mouth disease (HFMD) and occasionally causes severe neurological disease. Here we reviewed the global epidemiology and genotypic evolution of EV-A71 since 1997. The natural selection, mutation and recombination events observed in the genetic evolution were described. In addition, we have updated the antigenicity and virulence determinants that are known to date. Understanding EV-A71 epidemiology, genetic evolution, antigenicity, and virulence determinants can expand our insights of EV-A71 pathogenesis, which may benefit us in the future.
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Affiliation(s)
- Sheng-Wen Huang
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Tainan, Taiwan
| | - Dayna Cheng
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan
| | - Jen-Ren Wang
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan. .,Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Center of Infectious Disease and Signaling Research, National Cheng Kung University, One, University Road, Tainan, 701, Taiwan. .,Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan.
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19
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Enterovirus 71 targets the cardiopulmonary system in a robust oral infection mouse model. Sci Rep 2019; 9:11108. [PMID: 31366973 PMCID: PMC6668393 DOI: 10.1038/s41598-019-47455-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 07/17/2019] [Indexed: 12/21/2022] Open
Abstract
Severe infection with the re-emerging enterovirus 71 (EV71 or EV-A71) can cause cardiopulmonary failure. However, in patients' heart and lung, viral protein has not been detected. In mouse models, heart disease has not been reported. EV71-infected brainstem is generally believed to be responsible for the cardiopulmonary collapse. One major limitation in EV71 research is the lack of an efficient oral infection system using non-mouse-adapted clinical isolates. In a robust oral infection NOD/SCID mouse model, we detected EV71 protein at multiple organs, including heart and lung, in 100% of moribund mice with limb paralysis. Infiltrating leukocytes were always detected in heart and muscle, and VP1-positive M2 macrophages were abundant in the lung. Functional dissection on the pathogenesis mechanism revealed severe apoptosis, inflammatory cytokines, and abnormal electrocardiogram (EKG) in orally infected hearts. Therefore, cardiopulmonary disease could be one plausible cause of death in this mouse model. Inoculation of EV71 through an oral route resulted in viral infection in the intestine, viremia, and EV71 appeared to spread to peripheral tissues via blood circulation. Infectious virus was no longer detected in the blood on day 5 post-infection by the plaque formation assay. We demonstrated that both EV71 clinical isolate and cloned virus can target the cardiopulmonary system via a natural infection-like oral route.
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20
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Enterovirus A71 Containing Codon-Deoptimized VP1 and High-Fidelity Polymerase as Next-Generation Vaccine Candidate. J Virol 2019; 93:JVI.02308-18. [PMID: 30996087 DOI: 10.1128/jvi.02308-18] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 03/31/2019] [Indexed: 12/18/2022] Open
Abstract
Enterovirus A71 (EV-A71) is a major pathogen that causes hand-foot-and-mouth disease (HFMD), which occasionally results in severe neurological complications. In this study, we developed four EV-A71 (rgEV-A71) strains by reverse genetics procedures as possible vaccine candidates. The four rgEV-A71 viruses contained various codon-deoptimized VP1 capsid proteins (VP1-CD) and showed replication rates and antigenicity similar to that of the wild-type virus, while a fifth virus, rg4643C4VP-CD, was unable to form plaques but was still able to be examined by median tissue culture infectious dose (TCID50) titers, which were similar to those of the others, indicating the effect of CD on plaque formation. However, the genome stability showed that there were some mutations which appeared during just one passage of the VP1-CD viruses. Thus, we further constructed VP1-CD rgEV-A71 containing high-fidelity determinants in 3D polymerase (CD-HF), and the number of mutations in CD-HF rgEV-A71 was shown to have decreased. The CD-HF viruses showed less virulence than the parental strain in a mouse infection model. After 14 days postimmunization, antibody titers had increased in mice infected with CD-HF viruses. The mouse antisera showed similar neutralizing antibody titers against various CD-HF viruses and different genotypes of EV-A71. The study demonstrates the proof of concept that VP1 codon deoptimization combined with high-fidelity 3D polymerase decreased EV-A71 mutations and virulence in mice but retained their antigenicity, indicating it is a good candidate for next-generation EV-A71 vaccine development.IMPORTANCE EV-A71 can cause severe neurological diseases with fatality in infants and young children, but there are still no effective drugs to date. Here, we developed a novel vaccine strategy with the combination of CD and HF substitutions to generate the genetically stable reverse genetics virus. We found that CD combined with HF polymerase decreased the virulence but maintained the antigenicity of the virus. This work demonstrated the simultaneous introduction of CD genome sequences and HF substitutions as a potential new strategy to develop attenuated vaccine seed virus. Our work provides insight into the development of a low-virulence candidate vaccine virus through a series of genetic editing of virus sequences while maintaining its antigenicity and genome stability, which will provide an additional strategy for next-generation vaccine development of EV-A71.
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Yang CH, Liang CT, Jiang ST, Chen KH, Yang CC, Cheng ML, Ho HY. A Novel Murine Model Expressing a Chimeric mSCARB2/hSCARB2 Receptor Is Highly Susceptible to Oral Infection with Clinical Isolates of Enterovirus 71. J Virol 2019; 93:e00183-19. [PMID: 30894476 PMCID: PMC6532076 DOI: 10.1128/jvi.00183-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 03/15/2019] [Indexed: 01/05/2023] Open
Abstract
Enterovirus 71 (EV71) infection is generally associated with hand-foot-and-mouth disease (HFMD) and may cause severe neurological disorders and even death. An effective murine oral infection model for studying the pathogenesis of various clinical EV71 isolates is lacking. We developed a transgenic (Tg) mouse that expresses an EV71 receptor, that is, human scavenger receptor class B member 2 (hSCARB2), in a pattern highly similar to that of endogenous murine SCARB2 (mSCARB2) protein. A FLAG-tagged SCARB2 cDNA fragment composed of exons 3 to 12 was inserted into a murine Scarb2 gene-containing bacterial artificial chromosome (BAC) clone, and the resulting transgene was used for establishment of chimeric receptor-expressing Tg mice. Tg mice intragastrically (i.g.) infected with clinical isolates of EV71 showed neurological symptoms, such as ataxia and paralysis, and fatality. There was an age-dependent decrease in susceptibility to viral infection. Pathological characteristics of the infected Tg mice resembled those of encephalomyelitis in human patients. Viral infection was accompanied by microglial activation. Clodronate treatment of the brain slices from Tg mice enhanced viral replication, while lipopolysaccharide treatment significantly inhibited it, suggesting an antiviral role for microglia during EV71 infection. Taken together, this Tg mouse provides a model that closely mimics natural infection for studying EV71 pathogenesis and for evaluating the efficacy of vaccines or other antiviral drugs.IMPORTANCE The availability of a murine model of EV71 infection is beneficial for the understanding of pathogenic mechanisms and the development and assessment of vaccines and antiviral drugs. However, the lack of a murine oral infection model thwarted the study of pathogenesis induced by clinically relevant EV71 strains that are transmitted via the oral-oral or oral-fecal route. Our Tg mice could be intragastrically infected with clinically relevant EV71 strains in an efficient way and developed neurological symptoms and pathological changes strikingly resembling those of human infection. Moreover, these mice showed an age-dependent change in susceptibility that is similar to the human case. This Tg mouse, when combined with the use of other genetically modified mice, potentially contributes to studying the relationship between developmental changes in immunity and susceptibility to virus.
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Affiliation(s)
- Cheng-Hung Yang
- Graduate Institute of Biomedical Science, Chang Gung University, Guishan, Taoyuan, Taiwan
| | - Chung-Tiang Liang
- Novo Nordisk Research Centre, Department of Animal Facility, Discovery Biology, Beijing, China
| | - Si-Tse Jiang
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Kuan-Hsing Chen
- Kidney Research Center, Chang Gung Memorial Hospital at Linkou, Guishan, Taoyuan, Taiwan
| | - Chun-Chiao Yang
- Graduate Institute of Biomedical Science, Chang Gung University, Guishan, Taoyuan, Taiwan
| | - Mei-Ling Cheng
- Graduate Institute of Biomedical Science, Chang Gung University, Guishan, Taoyuan, Taiwan
- Healthy Aging Research Center, Chang Gung University, Guishan, Taoyuan, Taiwan
- Clinical Phenome Center, Chang Gung Memorial Hospital at Linkou, Guishan, Taoyuan, Taiwan
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Hung-Yao Ho
- Graduate Institute of Biomedical Science, Chang Gung University, Guishan, Taoyuan, Taiwan
- Healthy Aging Research Center, Chang Gung University, Guishan, Taoyuan, Taiwan
- Clinical Phenome Center, Chang Gung Memorial Hospital at Linkou, Guishan, Taoyuan, Taiwan
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Research Center for Emerging Viral Infections, Chang Gung University, Taoyuan, Taiwan
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22
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Enterovirus A71 VP1 Variation A289T Decreases the Central Nervous System Infectivity via Attenuation of Interactions between VP1 and Vimentin In Vitro and In Vivo. Viruses 2019; 11:v11050467. [PMID: 31121933 PMCID: PMC6563288 DOI: 10.3390/v11050467] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/15/2019] [Accepted: 05/20/2019] [Indexed: 12/30/2022] Open
Abstract
Vimentin (VIM) is a surface receptor for enterovirus-A71, mediating the initial binding and subsequent increase in EV-A71 infectivity. The caspid protein VP1 variation, A289T, is reportedly closely associated with less severe central nervous system (CNS) infections in humans. However, it is unclear whether VIM is associated with a reduction in CNS infections of EV-A71 in the presence of A289T. We investigated whether VIM served as a receptor for EV-A71 in the presence of an A298T substitution in VP1. EV-A71-289A and EV-A71-289T were used to infect human rhabdomyosarcoma cells, control human brain microvascular endothelial cells (HBMECs), and VIM-knockout (KO) HBMECs and inoculated BALB/c mice, SV129 mice, and VIM-KO SV129 mice. Furthermore, we cloned VP1-289A-Flag and VP1-289T-Flag proteins for co-immunoprecipitation analysis. Analysis of viral function revealed that the capacity of viral attachment, replication, and protein synthesis and secretion decreased in HBMECs during an EV-A71-289A infection, the infectivity being higher than that of EV-A71-289T upon VIM-KO. Histopathological and immunohistochemical analyses of brain tissue revealed that cerebral cortical damage was more extensive in EV-A71-289A than in EV-A71-289T infections in control SV129 mice; however, no significant difference was observed upon VIM-KO. Co-immunoprecipitation analysis revealed an interaction between VP1 and VIM, which was attenuated in VP1 harboring A289T; however, this attenuation was reversed by VIM (1-58) peptide. The A289T variation of VP1 specifically decreased the virulence of EV-A71 in HBMECs, and the attenuated interaction between VP1 harboring the A289T variation and VIM essentially decreased the CNS infectivity of EV-A71 in vitro and vivo.
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23
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Zhu J, Chen N, Zhou S, Zheng K, Sun L, Zhang Y, Cao L, Zhang X, Xiang Q, Chen Z, Wang C, Fan C, He Q. Severity of enterovirus A71 infection in a human SCARB2 knock-in mouse model is dependent on infectious strain and route. Emerg Microbes Infect 2018; 7:205. [PMID: 30518755 PMCID: PMC6281673 DOI: 10.1038/s41426-018-0201-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 09/10/2018] [Accepted: 10/25/2018] [Indexed: 11/30/2022]
Abstract
Enterovirus A71 (EV-A71) is a major etiological agent of human hand, foot and mouth disease, and it can cause severe neurological complications. Although several genotypes of EV-A71 strains are prevalent in different regions of the world, the genotype C4 has circulated in mainland China for more than 20 years. The pathogenicity of different EV-A71 clinical isolates varies and needs to be explored. In this study, hSCARB2 knock-in mice (N = 181) with a wide range of ages were tested for their susceptibility to two EV-A71 strains with the subgenotypes C4 and C2, and two infection routes (intracranial and venous) were compared. The clinical manifestations and pathology and their relationship to the measured viral loads in different tissues were monitored. We observed that 3 weeks is a crucial age, as mice younger than 3-week-old that were infected became extremely ill. However, mice older than 3 weeks displayed diverse clinical symptoms. Significant differences were observed in the pathogenicity of the two strains with respect to clinical signs, disease incidence, survival rate, and body weight change. We concluded that hSCARB2 knock-in mice are a sensitive model for investigating the clinical outcomes resulting from infection by different EV-A71 strains. The intracranial infection model appears to be suitable for evaluating EV-A71 neurovirulence, whereas the venous infection model is appropriate for studying the pathogenicity of EV-A71.
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Affiliation(s)
- Junping Zhu
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China
| | - Ning Chen
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China
| | - Shuya Zhou
- Division of Animal Model Research, Institute for Laboratory Animal Resources, National Institutes for Food and Drug Control, Beijing, 100050, China
| | - Kai Zheng
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China
| | - Lin Sun
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China
| | - Yuxiao Zhang
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China
| | - Lina Cao
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China
| | - Xiaoyan Zhang
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China
| | - Qiaoyan Xiang
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China
| | - Zhiyun Chen
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China
| | - Chenfei Wang
- Division of Animal Model Research, Institute for Laboratory Animal Resources, National Institutes for Food and Drug Control, Beijing, 100050, China
| | - Changfa Fan
- Division of Animal Model Research, Institute for Laboratory Animal Resources, National Institutes for Food and Drug Control, Beijing, 100050, China.
| | - Qiushui He
- Department of Medical Microbiology, Capital Medical University, Beijing, 100069, China.
- Department of Medical Microbiology and Immunology, University of Turku, Turku, 20520, Finland.
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Immunocompetent and Immunodeficient Mouse Models for Enterovirus 71 Pathogenesis and Therapy. Viruses 2018; 10:v10120674. [PMID: 30487421 PMCID: PMC6316343 DOI: 10.3390/v10120674] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 11/23/2018] [Accepted: 11/26/2018] [Indexed: 12/29/2022] Open
Abstract
Enterovirus 71 (EV71) is a global health threat. Children infected with EV71 could develop hand-foot-and-mouth disease (HFMD), encephalitis, paralysis, pulmonary edema, and death. At present, no effective treatment for EV71 is available. We reviewed here various mouse models for EV71 pathogenesis and therapy. Earlier studies relied on the use of mouse-adapted EV71 strains. To avoid artificial mutations arising de novo during the serial passages, recent studies used EV71 clinical isolates without adaptation. Several human receptors for EV71 were shown to facilitate viral entry in cell culture. However, in vivo infection with human SCARB2 receptor transgenic mice appeared to be more limited to certain strains and genotypes of EV71. Efficacy of oral infection in these transgenic models is extremely low. Intriguingly, despite the lack of human receptors, immunodeficient neonatal mouse models can still be infected with EV71 clinical isolates via oral or intraperitoneal routes. Crossbreeding between SCARB2 transgenic and stat1 knockout mice generated a more sensitive and user-friendly hybrid mouse model. Infected hybrid mice developed a higher incidence and earlier onset of CNS disease and death. Different pathogenesis profiles were observed in models deficient in various arms of innate or humoral immunity. These models are being actively used for antiviral research.
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Kobayashi K, Sudaka Y, Takashino A, Imura A, Fujii K, Koike S. Amino Acid Variation at VP1-145 of Enterovirus 71 Determines Attachment Receptor Usage and Neurovirulence in Human Scavenger Receptor B2 Transgenic Mice. J Virol 2018; 92:e00681-18. [PMID: 29848584 PMCID: PMC6052303 DOI: 10.1128/jvi.00681-18] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 05/18/2018] [Indexed: 12/23/2022] Open
Abstract
Infection by enterovirus 71 (EV71) is affected by cell surface receptors, including the human scavenger receptor B2 (hSCARB2), which are required for viral uncoating, and attachment receptors, such are heparan sulfate (HS), which bind virus but do not support uncoating. Amino acid residue 145 of the capsid protein VP1 affects viral binding to HS and virulence in mice. However, the contribution of this amino acid to pathogenicity in humans is not known. We produced EV71 having glycine (VP1-145G) or glutamic acid (VP1-145E) at position 145. VP1-145G, but not VP1-145E, enhanced viral infection in cell culture in an HS-dependent manner. However, VP1-145G virus showed an attenuated phenotype in wild-type suckling mice and in a transgenic mouse model expressing hSCARB2, while VP1-145E virus showed a virulent phenotype in both models. Thus, the HS-binding property and in vivo virulence are negatively correlated. Immunohistochemical analyses showed that HS is highly expressed in vascular endothelial cells and some other cell types where hSCARB2 is expressed at low or undetectable levels. VP1-145G virus bound to tissue homogenate of both hSCARB2 transgenic and nontransgenic mice in vitro, and the viral titer was reduced in the bloodstream immediately after intravenous inoculation. Furthermore, VP1-145G virus failed to disseminate well in the mouse organs. These data suggest that VP1-145G virus is adsorbed by attachment receptors such as HS during circulation in vivo, leading to abortive infection of HS-positive cells. This trapping effect is thought to be a major mechanism of attenuation of the VP1-145G virus.IMPORTANCE Attachment receptors expressed on the host cell surface are thought to enhance EV71 infection by increasing the chance of encountering true receptors. Although this has been confirmed using cell culture for some viruses, the importance of attachment receptors in vivo is unknown. This report provides an unexpected answer to this question. We demonstrated that the VP1-145G virus binds to HS and shows an attenuated phenotype in an hSCARB2-dependent animal infection model. HS is highly expressed in cells that express hSCARB2 at low or undetectable levels. Our data indicate that HS binding directs VP1-145G virus toward abortive infection and keeps virus away from hSCARB2-positive cells. Thus, although the ability of VP1-145G virus to use HS might be an advantage in replication in certain cultured cells, it becomes a serious disadvantage in replication in vivo This adsorption is thought to be a major mechanism of attenuation associated with attachment receptor usage.
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Affiliation(s)
- Kyousuke Kobayashi
- Neurovirology Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yui Sudaka
- Neurovirology Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Ayako Takashino
- Neurovirology Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Ayumi Imura
- Neurovirology Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Ken Fujii
- Neurovirology Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Satoshi Koike
- Neurovirology Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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VP1 Amino Acid Residue 145 of Enterovirus 71 Is a Key Residue for Its Receptor Attachment and Resistance to Neutralizing Antibody during Cynomolgus Monkey Infection. J Virol 2018; 92:JVI.00682-18. [PMID: 29848582 DOI: 10.1128/jvi.00682-18] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 05/18/2018] [Indexed: 12/24/2022] Open
Abstract
Enterovirus 71 (EV71) is a causative agent of hand, foot, and mouth disease and sometimes causes severe or fatal neurological complications. The amino acid at VP1-145 determines the virological characteristics of EV71. Viruses with glutamic acid (E) at VP1-145 (VP1-145E) are virulent in neonatal mice and transgenic mice expressing human scavenger receptor B2, whereas those with glutamine (Q) or glycine (G) are not. However, the contribution of this variation to pathogenesis in humans is not fully understood. We compared the virulence of VP1-145E and VP1-145G viruses of Isehara and C7/Osaka backgrounds in cynomolgus monkeys. VP1-145E, but not VP1-145G, viruses induced neurological symptoms. VP1-145E viruses were frequently detected in the tissues of infected monkeys. VP1-145G viruses were detected less frequently and disappeared quickly. Instead, mutants that had a G-to-E mutation at VP1-145 emerged, suggesting that VP1-145E viruses have a replication advantage in the monkeys. This is consistent with our hypothesis proposed in the accompanying paper (K. Kobayashi, Y. Sudaka, A. Takashino, A. Imura, K. Fujii, and S. Koike, J Virol 92:e00681-18, 2018, https://doi.org/10.1128/JVI.00681-18) that the VP1-145G virus is attenuated due to its adsorption by heparan sulfate. Monkeys infected with both viruses produced neutralizing antibodies before the onset of the disease. Interestingly, VP1-145E viruses were more resistant to neutralizing antibodies than VP1-145G viruses in vitro A small amount of neutralizing antibody raised in the early phase of infection may not be sufficient to block the dissemination of VP1-145E viruses. The different resistance of the VP1-145 variants to neutralizing antibodies may be one of the reasons for the difference in virulence.IMPORTANCE The contribution of VP1-145 variants in humans is not fully understood. In some studies, VP1-145G/Q viruses were isolated more frequently from severely affected patients than from mildly affected patients, suggesting that VP1-145G/Q viruses are more virulent. In the accompanying paper (K. Kobayashi, Y. Sudaka, A. Takashino, A. Imura, K. Fujii, and S. Koike, J Virol 92:e00681-18, 2018, https://doi.org/10.1128/JVI.00681-18), we showed that VP1-145E viruses are more virulent than VP1-145G viruses in human SCARB2 transgenic mice. Heparan sulfate acts as a decoy to specifically trap the VP1-145G viruses and leads to abortive infection. Here, we demonstrated that VP1-145G was attenuated in cynomolgus monkeys, suggesting that this hypothesis is also true in a nonhuman primate model. VP1-145E viruses, but not VP1-145G viruses, were highly resistant to neutralizing antibodies. We propose the difference in resistance against neutralizing antibodies as another mechanism of EV71 virulence. In summary, VP1-145 contributes to virulence determination by controlling attachment receptor usage and antibody sensitivity.
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Pathinayake PS, Gayan Chathuranga WA, Lee HC, Chowdhury MYE, Sung MH, Lee JS, Kim CJ. Inactivated enterovirus 71 with poly-γ-glutamic acid/Chitosan nano particles (PC NPs) induces high cellular and humoral immune responses in BALB/c mice. Arch Virol 2018; 163:2073-2083. [DOI: 10.1007/s00705-018-3837-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 02/26/2018] [Indexed: 01/08/2023]
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RSAD2 and AIM2 Modulate Coxsackievirus A16 and Enterovirus A71 Replication in Neuronal Cells in Different Ways That May Be Associated with Their 5' Nontranslated Regions. J Virol 2018; 92:JVI.01914-17. [PMID: 29263272 DOI: 10.1128/jvi.01914-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 11/27/2017] [Indexed: 12/30/2022] Open
Abstract
Coxsackievirus A16 (CV-A16) and enterovirus A71 (EV-A71) are closely related enteroviruses that cause the same hand, foot, and mouth disease (HFMD), but neurological complications occur only very rarely in CV-A16 compared to EV-A71 infections. To elucidate host responses that may be able to explain these differences, we performed transcriptomic analysis and real-time quantitative PCR (RT-qPCR) in CV-A16-infected neuroblastoma cells (SK-N-SH), and the results showed that the radical S-adenosylmethionine domain containing 2 (RSAD2) was the highest upregulated gene in the antimicrobial pathway. Increased RSAD2 expression was correlated with reduced viral replication, while RSAD2 knockdown cells were correlated with increased replication. EV-A71 replication showed no apparent correlation to RSAD2 expressions. Absent in melanoma 2 (AIM2), which is associated with pyroptotic cell death, was upregulated in EV-A71-infected neurons but not in CV-A16 infection, suggesting that the AIM2 inflammasome played a significant role in suppressing EV-A71 replication. Chimeric viruses derived from CV-A16 and EV-A71 but containing swapped 5' nontranslated regions (5' NTRs) showed that RSAD2 expression/viral replication and AIM2 expression/viral replication patterns may be linked to the 5' NTRs of parental viruses. Differences in secondary structure of internal ribosomal entry sites within the 5' NTR may be responsible for these findings. Overall, our results suggest that CV-A16 and EV-A71 elicit different host responses to infection, which may help explain the apparent lower incidence of CV-A16-associated neurovirulence in HFMD outbreaks compared to EV-A71 infection.IMPORTANCE Although coxsackievirus A16 (CV-A16) and enterovirus A17 (EV-A71) both cause hand, foot, and mouth disease, EV-A71 has emerged as a leading cause of nonpolio, enteroviral fatal encephalomyelitis among young children. The significance of our research is in the identification of the possible differing and novel mechanisms of CV-A16 and EV-A71 inhibition in neuronal cells that may impact viral neuropathogenesis. We further showed that viral 5' NTRs may play significant roles in eliciting different host response mechanisms.
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29
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Cox JA, Hiscox JA, Solomon T, Ooi MH, Ng LFP. Immunopathogenesis and Virus-Host Interactions of Enterovirus 71 in Patients with Hand, Foot and Mouth Disease. Front Microbiol 2017; 8:2249. [PMID: 29238324 PMCID: PMC5713468 DOI: 10.3389/fmicb.2017.02249] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 10/31/2017] [Indexed: 12/12/2022] Open
Abstract
Enterovirus 71 (EV71) is a global infectious disease that affects millions of people. The virus is the main etiological agent for hand, foot, and mouth disease with outbreaks and epidemics being reported globally. Infection can cause severe neurological, cardiac, and respiratory problems in children under the age of 5. Despite on-going efforts, little is known about the pathogenesis of EV71, how the host immune system responds to the virus and the molecular mechanisms behind these responses. Moreover, current animal models remain limited, because they do not recapitulate similar disease patterns and symptoms observed in humans. In this review the role of the host-viral interactions of EV71 are discussed together with the various models available to examine: how EV71 utilizes its proteins to cleave host factors and proteins, aiding virus replication; how EV71 uses its own viral proteins to disrupt host immune responses and aid in its immune evasion. These discoveries along with others, such as the EV71 crystal structure, have provided possible targets for treatment and drug interventions.
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Affiliation(s)
- Jonathan A. Cox
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore, Singapore
| | - Julian A. Hiscox
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore, Singapore
- NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, Liverpool, United Kingdom
| | - Tom Solomon
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
- NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, Liverpool, United Kingdom
- Walton Centre NHS Foundation Trust, Liverpool, United Kingdom
| | - Mong-How Ooi
- Institute of Health and Community Medicine, Universiti Malaysia Sarawak, Samarahan, Malaysia
- Department of Paediatrics, Sarawak General Hospital, Kuching, Malaysia
| | - Lisa F. P. Ng
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore, Singapore
- NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, Liverpool, United Kingdom
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30
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A Selective Bottleneck Shapes the Evolutionary Mutant Spectra of Enterovirus A71 during Viral Dissemination in Humans. J Virol 2017; 91:JVI.01062-17. [PMID: 28931688 DOI: 10.1128/jvi.01062-17] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 09/14/2017] [Indexed: 12/15/2022] Open
Abstract
RNA viruses accumulate mutations to rapidly adapt to environmental changes. Enterovirus A71 (EV-A71) causes various clinical manifestations with occasional severe neurological complications. However, the mechanism by which EV-A71 evolves within the human body is unclear. Utilizing deep sequencing and haplotype analyses of viruses from various tissues of an autopsy patient, we sought to define the evolutionary pathway by which enterovirus A71 evolves fitness for invading the central nervous system in humans. Broad mutant spectra with divergent mutations were observed at the initial infection sites in the respiratory and digestive systems. After viral invasion, we identified a haplotype switch and dominant haplotype, with glycine at VP1 residue 31 (VP1-31G) in viral particles disseminated into the integumentary and central nervous systems. In vitro viral growth and fitness analyses indicated that VP1-31G conferred growth and a fitness advantage in human neuronal cells, whereas VP1-31D conferred enhanced replication in human colorectal cells. A higher proportion of VP1-31G was also found among fatal cases, suggesting that it may facilitate central nervous system infection in humans. Our data provide the first glimpse of EV-A71 quasispecies from oral tissues to the central nervous system within humans, showing broad implications for the surveillance and pathogenesis of this reemerging viral pathogen.IMPORTANCE EV-A71 continues to be a worldwide burden to public health. Although EV-A71 is the major etiological agent of hand, foot, and mouth disease, it can also cause neurological pulmonary edema, encephalitis, and even death, especially in children. Understanding selection processes enabling dissemination and accurately estimating EV-A71 diversity during invasion in humans are critical for applications in viral pathogenesis and vaccine studies. Here, we define a selection bottleneck appearing in respiratory and digestive tissues. Glycine substitution at VP1 residue 31 helps viruses break through the bottleneck and invade the central nervous system. This substitution is also advantageous for replication in neuronal cells in vitro Considering that fatal cases contain enhanced glycine substitution at VP1-31, we suggest that the increased prevalence of VP1-31G may alter viral tropism and aid central nervous system invasion. Our findings provide new insights into a dynamic mutant spectral switch active during acute viral infection with emerging viral pathogens.
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31
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Zhang Y, Han H, Sun L, Qiu H, Lin H, Yu L, Zhu W, Qi J, Yang R, Pang Y, Wang X, Lu G, Yang Y. Antiviral activity of shikonin ester derivative PMM-034 against enterovirus 71 in vitro. ACTA ACUST UNITED AC 2017; 50:e6586. [PMID: 28832767 PMCID: PMC5561812 DOI: 10.1590/1414-431x20176586] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 07/03/2017] [Indexed: 12/20/2022]
Abstract
Human enterovirus 71 (EV71) is the major causative agent of hand, foot, and mouth disease (HFMD), particularly in infants and children below 4 years of age. Shikonin is a bioactive compound with anti-inflammatory, antiviral, and antibacterial activities derived from the roots of the Chinese medicinal herb Lithospermum erythrorhizon. This study aimed to examine the antiviral activity of PMM-034, a shikonin ester derivative, against EV71 in rhabdomyosarcoma (RD) cells. Cytotoxicity of PMM-034 on RD cells was determined using WST-1 assay. Dose- and time-dependent effects of PMM-034 on EV71 replication in RD cells were determined using plaque reduction assay. mRNA expression levels of EV71/VP1 and pro-inflammatory cytokines (IL-1β, IL-6, IL-8, and TNF-α) were determined by real-time RT-PCR, and EV71/VP1 and phospho-p65 protein expressions were determined by western blot analysis. PMM-034 exhibited only weak cytotoxicity against RD cells. However, PMM-034 exhibited significant antiviral activity against EV71 in RD cells with 50% inhibitory concentration of 2.31 μg/mL. The VP1 mRNA and protein levels were significantly reduced in cells treated with PMM-034. Furthermore, relative mRNA expression levels of IL-1β, IL-6, IL-8, and TNF-α significantly decreased in the cells treated with PMM-034, while the phospho-p65 protein expression was also significantly lower in the treated cells. These results indicated that PMM-034 suppressed the expressions of pro-inflammatory cytokines in RD cells, exhibiting antiviral activity against EV71, as evidenced by the reduced VP1 mRNA and protein levels in PMM-034-treated cells. Thus, PMM-034 is a promising candidate for further development as an EV71 inhibitor.
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Affiliation(s)
- Y Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China.,Suzhou Industrial Park Center for Disease Control and Prevention, Suzhou, China
| | - H Han
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China
| | - L Sun
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - H Qiu
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China
| | - H Lin
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China
| | - L Yu
- Suzhou Industrial Park Center for Disease Control and Prevention, Suzhou, China
| | - W Zhu
- Suzhou Industrial Park Center for Disease Control and Prevention, Suzhou, China
| | - J Qi
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China
| | - R Yang
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China
| | - Y Pang
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China
| | - X Wang
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China
| | - G Lu
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China
| | - Y Yang
- State Key Laboratory of Pharmaceutical Biotechnology, NJU-NJFU Joint Institute of Plant Molecular Biology, Nanjing University, Nanjing, China
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Feng M, Guo S, Fan S, Zeng X, Zhang Y, Liao Y, Wang J, Zhao T, Wang L, Che Y, Wang J, Ma N, Liu L, Yue L, Li Q. The Preferential Infection of Astrocytes by Enterovirus 71 Plays a Key Role in the Viral Neurogenic Pathogenesis. Front Cell Infect Microbiol 2016; 6:192. [PMID: 28066727 PMCID: PMC5174126 DOI: 10.3389/fcimb.2016.00192] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 12/07/2016] [Indexed: 02/06/2023] Open
Abstract
The pathological manifestations of fatal cases of human hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) are characterized by inflammatory damage to the central nervous system (CNS). Here, the dynamic distribution of EV71 in the CNS and the subsequent pathological characteristics within different regions of neonatal rhesus macaque brain tissue were studied using a chimeric EV71 expressing green fluorescence protein. The results were compared with brain tissue obtained from the autopsies of deceased EV71-infected HFMD patients. These observations suggested that the virus was prevalent in areas around the blood vessels and nerve nuclei in the brain stem and showed a preference for astrocytes in the CNS. Interestingly, infected astrocytes within the in vivo and in vitro human and macaque systems exhibited increased expression of excitatory neurotransmitters and cytokines that also stimulated the neuronal secretion of the excitatory neurotransmitters noradrenalin and adrenalin, and this process most likely plays a role in the pathophysiological events that occur during EV71 infection.
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Affiliation(s)
- Min Feng
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Sujie Guo
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Shengtao Fan
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Xiaofeng Zeng
- School of Forensic Medicine, Kunming Medical University Kunming, China
| | - Ying Zhang
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Yun Liao
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Jianbin Wang
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Ting Zhao
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Lichun Wang
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Yanchun Che
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Jingjing Wang
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Na Ma
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Longding Liu
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Lei Yue
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
| | - Qihan Li
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College Kunming, China
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33
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Tan CW, Sam IC, Lee VS, Wong HV, Chan YF. VP1 residues around the five-fold axis of enterovirus A71 mediate heparan sulfate interaction. Virology 2016; 501:79-87. [PMID: 27875780 DOI: 10.1016/j.virol.2016.11.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 11/13/2016] [Accepted: 11/15/2016] [Indexed: 11/19/2022]
Abstract
Enterovirus A71 (EV-A71) is a neurotropic enterovirus that uses heparan sulfate as an attachment receptor. The molecular determinants of EV-A71-heparan sulfate interaction are unknown. With In silico heparin docking and mutagenesis of all possible lysine residues in VP1, we identified that K162, K242 and K244 are responsible for heparin interaction and inhibition. EV-A71 mutants with K242A and K244A rapidly acquired compensatory mutations, T100K or E98A, and Q145R-T237N respectively, which restored the heparin-binding phenotype. Both VP1-98 and VP1-145 modulates heparin binding. Heparin-binding phenotype was completely abolished with VP1-E98-E145, but was restored by an E98K or E145Q substitution. During cell culture adaptation, EV-A71 rapidly acquired K98 or Q/G145 to restore the heparin-binding phenotype. Together with next-generation sequencing analysis, our results implied that EV-A71 has high genetic plasticity by modulating positively-charged residues at the five-fold axis during in vitro heparin adaptation. Our finding has impact on EV-A71 vaccine production, evolutionary studies and pathogenesis.
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Affiliation(s)
- Chee Wah Tan
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - I-Ching Sam
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Vannajan Sanghiran Lee
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia; Computational Simulation Modelling Laboratory (CSML), Department of Chemistry and Center of Excellence for Innovation in Chemistry and Materials Science Research Center, Faculty of Science, Chiang Mai University, Thailand
| | - Hui Vern Wong
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yoke Fun Chan
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
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Too IHK, Yeo H, Sessions OM, Yan B, Libau EA, Howe JLC, Lim ZQ, Suku-Maran S, Ong WY, Chua KB, Wong BS, Chow VTK, Alonso S. Enterovirus 71 infection of motor neuron-like NSC-34 cells undergoes a non-lytic exit pathway. Sci Rep 2016; 6:36983. [PMID: 27849036 PMCID: PMC5111112 DOI: 10.1038/srep36983] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 10/20/2016] [Indexed: 01/08/2023] Open
Abstract
Enterovirus 71 (EV71) causing Hand, Foot and Mouth Disease, is regarded as the most important neurotropic virus worldwide. EV71 is believed to replicate in muscles and infect motor neurons to reach the central nervous system (CNS). To further investigate the mechanisms involved, we have employed the motor neuron cell line NSC-34. NSC-34 cells were permissive to EV71 and virus production yields were strain-dependent with differential efficacy at the entry, replication and egress steps. Furthermore, unlike all the other cell lines previously reported, EV71-infected NSC-34 cells neither displayed cytopathic effect nor underwent apoptosis. Instead, autophagy was markedly up-regulated and virus-containing autophagic vacuoles were isolated from the culture supernatant, providing the first experimental evidence that EV71 can adopt a non-lytic exit pathway. Finally, the ability of EV71 to infect productively NSC-34 cells correlated with its ability to invade the CNS in vivo, supporting the relevance of NSC-34 cells to study the intrinsic neurovirulence of EV71 strains.
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Affiliation(s)
- Issac Horng Khit Too
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Huimin Yeo
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - October Michael Sessions
- Program in Emerging Infectious Diseases, Duke-NUS Graduate Medical School, 8 College Road, 169857, Singapore
| | - Benedict Yan
- Department of Laboratory Medicine, 5 Lower Kent Ridge Road, National University Hospital, 119074, Singapore
| | - Eshele Anak Libau
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Josephine L C Howe
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore
| | - Ze Qin Lim
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Shalini Suku-Maran
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Kaw Bing Chua
- Temasek Life Sciences Laboratory, 5 A Engineering Drive 1, National University of Singapore, 117411, Singapore
| | - Boon Seng Wong
- Neurobiology and Ageing Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Vincent T K Chow
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore
| | - Sylvie Alonso
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
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Liou AT, Wu SY, Liao CC, Chang YS, Chang CS, Shih C. A new animal model containing human SCARB2 and lacking stat-1 is highly susceptible to EV71. Sci Rep 2016; 6:31151. [PMID: 27499235 PMCID: PMC4976353 DOI: 10.1038/srep31151] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 07/14/2016] [Indexed: 12/04/2022] Open
Abstract
Enterovirus 71 (EV71) is a major threat to children worldwide. Children infected with EV71 could develop subclinical infection and hand-foot-and -mouth disease (HFMD). In severe cases, patients could develop encephalitis, paralysis, pulmonary edema, and death. A more user-friendly and robust animal model is essential to investigating EV71 pathogenesis. Here, we established a hybrid (hSCARB2(+/+)/stat-1(-/-)) mouse strain from crossbreeding SCARB2 transgenic and stat-1 KO mice, and compared the susceptibilities to EV71 infection and pathogenesis between parental and hybrid mice. Virus-encoded VP1 protein can be detected in the streaking nerve fibers in brain and spinal cord. This hybrid mouse strain at 2-week-old age can still be infected with different genotypes of EV71 at 1000-fold lower titer via an ip route. Infected hybrid mice developed earlier onset of CNS disease, paralysis, and death at a higher incidence. These advantages of this novel model meet the urgent need from the scientific community in basic and preclinical research in therapeutics and pathogenesis.
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Affiliation(s)
- An-Ting Liou
- Taiwan International Graduate Program (TIGP) in Molecular Medicine, National Yang-Ming University and Academia Sinica, Taipei, Taiwan
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Szu-Yao Wu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan
| | - Chun-Che Liao
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ya-Shu Chang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Chih-Shin Chang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan
| | - Chiaho Shih
- Taiwan International Graduate Program (TIGP) in Molecular Medicine, National Yang-Ming University and Academia Sinica, Taipei, Taiwan
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
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Ong KC, Wong KT. Understanding Enterovirus 71 Neuropathogenesis and Its Impact on Other Neurotropic Enteroviruses. Brain Pathol 2016; 25:614-24. [PMID: 26276025 DOI: 10.1111/bpa.12279] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 06/19/2015] [Indexed: 01/27/2023] Open
Abstract
Enterovirus A71 (EV-A71) belongs to the species group A in the Enterovirus genus within the Picornaviridae family. EV-A71 usually causes self-limiting hand, foot and mouth disease or herpangina but rarely causes severe neurological complications such as acute flaccid paralysis and encephalomyelitis. The pathology and neuropathogenesis of these neurological syndromes is beginning to be understood. EV-A71 neurotropism for motor neurons in the spinal cord and brainstem, and other neurons, is mainly responsible for central nervous system damage. This review on the general aspects, recent developments and advances of EV-A71 infection will focus on neuropathogenesis and its implications on other neurotropic enteroviruses, such as poliovirus and the newly emergent Enterovirus D68. With the imminent eradication of poliovirus, EV-A71 is likely to replace it as an important neurotropic enterovirus of worldwide importance.
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Affiliation(s)
- Kien Chai Ong
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kum Thong Wong
- Department of Pathology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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37
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Wang KT, Lin SJ, Wang HC, Chen PC, Lin JJ, Chiang JR, Chang CL, Shih DYC, Lo CF, Wang DY. Establishment of an animal challenge model as a potency assay for an inactivated Enterovirus Type 71 vaccine. Biologicals 2016; 44:183-190. [PMID: 27068365 DOI: 10.1016/j.biologicals.2016.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 12/29/2015] [Accepted: 01/22/2016] [Indexed: 11/19/2022] Open
Abstract
Enterovirus 71 (EV71) belongs to the Enterovirus genus of the Picornaviridae family, and its occurrence in Asia is associated with hand-foot-and-mouth disease (HFMD), leading to death in some cases, in young children. An effective EV71 vaccine is therefore urgently needed. In this study, we established a two-step EV71 vaccine potency model. Intraperitoneal injections in 2-day-old suckling mice were used to establish the LD50 of EV71 B4, B5, C2, C4, and C5 subgenotypes. Only C4 caused hind limb paralysis in mice (LD50: 2.62 ± 0.45). EV71 VP1 protein was identified in the brain tissues at histology. In the second phase of the model, 3-week-old female ICR mice received one primary and two boosting i.p. injections of formalin-inactivated EV71 B4 and C4 vaccine. Immunized serum was neutralized in vitro with EV71 C4 and applied to the murine challenge model. The C4 vaccine-immunized serum exhibited the highest protective titre (ED50 = 114.6), while the B4 immunized serum had the weakest protective titre (ED50 = 34.3). Additionally, human plasma and intravenous immunoglobulin displayed significant protection in the neutralization assay. Our results could facilitate candidate EV71 vaccine immunogenicity and efficacy evaluations, and may help establish reference EV71 antisera in the future.
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Affiliation(s)
- Kun-Teng Wang
- Food and Drug Administration, Ministry of Health and Welfare, Taiwan, ROC
| | - Shih-Jie Lin
- Food and Drug Administration, Ministry of Health and Welfare, Taiwan, ROC
| | - Hsiu-Chi Wang
- Food and Drug Administration, Ministry of Health and Welfare, Taiwan, ROC
| | - Pin-Chun Chen
- Food and Drug Administration, Ministry of Health and Welfare, Taiwan, ROC
| | - Jiao-Jung Lin
- Food and Drug Administration, Ministry of Health and Welfare, Taiwan, ROC
| | - Jen-Ron Chiang
- Centers for Disease Control, Ministry of Health and Welfare, Taiwan, ROC
| | - Chao-Liang Chang
- Food and Drug Administration, Ministry of Health and Welfare, Taiwan, ROC
| | | | - Chi-Fang Lo
- Food and Drug Administration, Ministry of Health and Welfare, Taiwan, ROC
| | - Der-Yuan Wang
- Food and Drug Administration, Ministry of Health and Welfare, Taiwan, ROC; National Taipei University of Technology, Taiwan, ROC.
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38
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Wen X, Cheng A, Wang M, Jia R, Zhu D, Chen S, Liu M, Sun K, Yang Q, Wu Y, Chen X. Recent advances from studies on the role of structural proteins in enterovirus infection. Future Microbiol 2015; 10:1529-42. [DOI: 10.2217/fmb.15.62] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Enteroviruses are a large group of small nonenveloped viruses that cause common and debilitating illnesses affecting humans and animals worldwide. The capsid composed by viral structural proteins packs the RNA genome. It is becoming apparent that structural proteins of enteroviruses play versatile roles in the virus–host interaction in the viral life cycle, more than just a shell. Furthermore, structural proteins to some extent may be associated with viral virulence and pathogenesis. Better understanding the roles of structural proteins in enterovirus infection may lead to the development of potential antiviral strategies. Here, we discuss recent advances from studies on the role of structural proteins in enterovirus infection and antiviral therapeutics targeted structural proteins.
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Affiliation(s)
- Xingjian Wen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Engineering & Technology Center for Laboratory Animals of Sichuan Agricultural University, Ya'an, Sichuan 625014, China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
| | - Dekang Zhu
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
| | - Kunfeng Sun
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
| | - Xiaoyue Chen
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, PR China
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The Role of VP1 Amino Acid Residue 145 of Enterovirus 71 in Viral Fitness and Pathogenesis in a Cynomolgus Monkey Model. PLoS Pathog 2015; 11:e1005033. [PMID: 26181772 PMCID: PMC4504482 DOI: 10.1371/journal.ppat.1005033] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 06/19/2015] [Indexed: 12/17/2022] Open
Abstract
Enterovirus 71 (EV71), a major causative agent of hand, foot, and mouth disease, occasionally causes severe neurological symptoms. We identified P-selectin glycoprotein ligand-1 (PSGL-1) as an EV71 receptor and found that an amino acid residue 145 in the capsid protein VP1 (VP1-145) defined PSGL-1-binding (PB) and PSGL-1-nonbinding (non-PB) phenotypes of EV71. However, the role of PSGL-1-dependent EV71 replication in neuropathogenesis remains poorly understood. In this study, we investigated viral replication, genetic stability, and the pathogenicity of PB and non-PB strains of EV71 in a cynomolgus monkey model. Monkeys were intravenously inoculated with cDNA-derived PB and non-PB strains of EV71, EV71-02363-EG and EV71-02363-KE strains, respectively, with two amino acid differences at VP1-98 and VP1-145. Mild neurological symptoms, transient lymphocytopenia, and inflammatory cytokine responses, were found predominantly in the 02363-KE-inoculated monkeys. During the early stage of infection, viruses were frequently detected in clinical samples from 02363-KE-inoculated monkeys but rarely in samples from 02363-EG-inoculated monkeys. Histopathological analysis of central nervous system (CNS) tissues at 10 days postinfection revealed that 02363-KE induced neuropathogenesis more efficiently than that induced by 02363-EG. After inoculation with 02363-EG, almost all EV71 variants detected in clinical samples, CNS, and non-CNS tissues, possessed a G to E amino acid substitution at VP1-145, suggesting a strong in vivo selection of VP1-145E variants and CNS spread presumably in a PSGL-1-independent manner. EV71 variants with VP1-145G were identified only in peripheral blood mononuclear cells in two out of four 02363-EG-inoculated monkeys. Thus, VP1-145E variants are mainly responsible for the development of viremia and neuropathogenesis in a non-human primate model, further suggesting the in vivo involvement of amino acid polymorphism at VP1-145 in cell-specific viral replication, in vivo fitness, and pathogenesis in EV71-infected individuals. Recently, large outbreaks of hand, foot, and mouth disease, including fatal neurological cases in young children primarily because of enterovirus 71 (EV71) have been reported, particularly in the Asia Pacific regions where the disease poses a serious threat to public health. Based on mutational and structural analyses of EV71, we identified amino acid residue 145 of the capsid protein VP1 (VP1-145) as a critical molecular determinant for the binding of EV71 to a specific cellular receptor, human P-selectin glycoprotein ligand-1 (PSGL-1). VP1-145 is highly variable among EV71 isolates and has been identified as a potential neurovirulence determinant in humans and experimental mouse models. To elucidate the in vivo involvement of PSGL-1-depentent replication and pathogenesis, we investigated viral replication, genetic stability, and the pathogenicity of the PSGL-1-binding (PB) and PSGL-1-nonbinding (non-PB) strains of EV71 in a cynomolgus monkey model. After the intravenous inoculation with the PB strain, viruses found to be highly mutated at VP1-145 with resultant VP1-145E variants (non-PB) inducing viremia and neuropathogenesis, presumably in a PSGL-1-independent manner. VP1-145G variants were identified only in peripheral blood mononuclear cells from two PB-inoculated monkeys. Our study provides new insights into the interplay between virus, receptors, and host in EV71-infected individuals.
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40
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Lei X, Cui S, Zhao Z, Wang J. Etiology, pathogenesis, antivirals and vaccines of hand, foot, and mouth disease. Natl Sci Rev 2015. [DOI: 10.1093/nsr/nwv038] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Abstract
Hand, foot, and mouth disease (HFMD), caused by enteroviruses, is a syndrome characterized by fever with vesicular eruptions mainly on the skin of the hands, feet, and oral cavity. HFMD primarily affects infants and young children. Although infection is usually self-limited, severe neurological complications in the central nervous system can present in some cases, which can lead to death. Widespread infection of HFMD across the Asia-Pacific region over the past two decades has made HFMD a major public health challenge, ranking first among the category C notifiable communicable diseases in China every year since 2008. This review summarizes our understanding of HFMD, focusing on the etiology and pathogenesis of the disease, as well as on progress toward antivirals and vaccines. The review also discusses the implications of these studies as they relate to the control and prevention of the disease.
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Affiliation(s)
- Xiaobo Lei
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Sheng Cui
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Zhendong Zhao
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Jianwei Wang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou 310003, China
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Hou W, Yang L, Li S, Yu H, Xu L, He D, Chen M, He S, Ye X, Que Y, Shih JWK, Cheng T, Xia N. Construction and characterization of an infectious cDNA clone of Echovirus 25. Virus Res 2015; 205:41-4. [PMID: 26004198 DOI: 10.1016/j.virusres.2015.05.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 05/05/2015] [Accepted: 05/12/2015] [Indexed: 12/28/2022]
Abstract
Echovirus 25 (E-25) is a member of the enterovirus family and a common pathogen that induces hand, foot, and mouth disease (HFMD), meningitis, skin rash, and respiratory illnesses. In this study, we constructed and characterized an infectious full-length E-25 cDNA clone derived from the XM0297 strain, which was the first subgenotype D6 strain isolated in Xiamen, China. The 5'-Untranslated Regions (5'-UTR), P3 (3A-3B, 3D) and P3 (3C) regions of this E-25 (XM0297) strain were highly similar to EV-B77, E-16 and E-13, respectively. Our data demonstrate that the rescued E-25 viruses exhibited similar growth kinetics to the prototype virus strain XM0297. We observed the rescued viral particles using transmission electron microscope (TEM) and found them to possess an icosahedral structure, with a diameter of approximately 30 nm. The cross neutralization test demonstrated that the E-25 (XM0297) strain immune serum could not neutralize EV-A71, CV-A16 or CV-B3; likewise, the EV-A71 and CV-A16 immune serum could not neutralize E-25 (XM0297). The availability of this infectious clone will greatly enhance future virological investigations and possible vaccine development against E-25.
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Affiliation(s)
- Wangheng Hou
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China
| | - Lisheng Yang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China
| | - Shuxuan Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China
| | - Hai Yu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China
| | - Longfa Xu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China
| | - Delei He
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China
| | - Mengyuan Chen
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China
| | - Shuizhen He
- Xiamen Center for Disease Control and Prevention, Fujian, China
| | - Xiangzhong Ye
- Beijing Wantai Biological Pharmacy Enterprise Co., Ltd., Beijing 102206, PR China
| | - Yuqiong Que
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China
| | - James Wai Kuo Shih
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China
| | - Tong Cheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China.
| | - Ningshao Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen 361102, PR China.
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42
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Enterovirus 71 infection causes severe pulmonary lesions in gerbils, meriones unguiculatus, which can be prevented by passive immunization with specific antisera. PLoS One 2015; 10:e0119173. [PMID: 25767882 PMCID: PMC4359154 DOI: 10.1371/journal.pone.0119173] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 01/10/2015] [Indexed: 01/28/2023] Open
Abstract
Neurogenic pulmonary edema caused by severe brainstem encephalitis is the leading cause of death in young children infected by Enterovirus 71 (EV71). However, no pulmonary lesions have been found in EV71-infected transgenic or non-transgenic mouse models. Development of a suitable animal model is important for studying EV71 pathogenesis and assessing effect of therapeutic approaches. We had found neurological disorders in EV71-induced young gerbils previously. Here, we report severe pulmonary lesions characterized with pulmonary congestion and hemorrhage in a gerbil model for EV71 infection. In the EV71-infected gerbils, six 21-day-old or younger gerbils presented with a sudden onset of symptoms and rapid illness progression after inoculation with 1×105.5 TCID50 of EV71 via intraperitoneal (IP) or intramuscular (IM) route. Respiratory symptoms were observed along with interstitial pneumonia, pulmonary congestion and extensive lung hemorrhage could be detected in the lung tissues by histopathological examination. EV71 viral titer was found to be peak at late stages of infection. EV71-induced pulmonary lesions, together with severe neurological disorders were also observed in gerbils, accurately mimicking the disease process in EV71-infected patients. Passive transfer with immune sera from EV71 infected adult gerbils with a neutralizing antibody (GMT=89) prevented severe pulmonary lesion formation after lethal EV71 challenge. These results establish this gerbil model as a useful platform for studying the pathogenesis of EV71-induced pulmonary lesions, immunotherapy and antiviral drugs.
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Hsiao HB, Chou AH, Lin SI, Lien SP, Liu CC, Chong P, Chen CY, Tao MH, Liu SJ. Delivery of human EV71 receptors by adeno-associated virus increases EV71 infection-induced local inflammation in adult mice. BIOMED RESEARCH INTERNATIONAL 2014; 2014:878139. [PMID: 25243194 PMCID: PMC4163470 DOI: 10.1155/2014/878139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 07/22/2014] [Accepted: 07/28/2014] [Indexed: 11/17/2022]
Abstract
Enterovirus71 (EV71) is now recognized as an emerging neurotropic virus in Asia and one major causative agent of hand-foot-mouth diseases (HFMD). However potential animal models for vaccine development are limited to young mice. In this study, we used an adeno-associated virus (AAV) vector to introduce the human EV71 receptors P-selectin glycoprotein ligand-1 (hPSGL1) or a scavenger receptor class-B member-2 (hSCARB2) into adult ICR mice to change their susceptibility to EV71 infection. Mice were administered AAV-hSCARB2 or AAV-hPSGL1 through intravenous and oral routes. After three weeks, expression of human SCARB2 and PSGL1 was detected in various organs. After infection with EV71, we found that the EV71 viral load in AAV-hSCARB2- or AAV-hPSGL1-transduced mice was higher than that of the control mice in both the brain and intestines. The presence of EV71 viral particles in tissues was confirmed using immunohistochemistry analysis. Moreover, inflammatory cytokines were induced in the brain and intestines of AAV-hSCARB2- or AAV-hPSGL1-transduced mice after EV71 infection but not in wild-type mice. However, neurological disease was not observed in these animals. Taken together, we successfully infected adult mice with live EV71 and induced local inflammation using an AAV delivery system.
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Affiliation(s)
- Hung-Bo Hsiao
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli 35053, Taiwan
| | - Ai-Hsiang Chou
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli 35053, Taiwan
| | - Su-I Lin
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli 35053, Taiwan
| | - Shu-Pei Lien
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli 35053, Taiwan
| | - Chia-Chyi Liu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli 35053, Taiwan
| | - Pele Chong
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli 35053, Taiwan
- Graduate Institute of Immunology, China Medical University, Taichung 40402, Taiwan
| | - Chih-Yeh Chen
- Institutes of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan
- Graduate Institute of Microbiology, National Taiwan University, Taipei 10051, Taiwan
| | - Mi-Hua Tao
- Institutes of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan
| | - Shih-Jen Liu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli 35053, Taiwan
- Graduate Institute of Immunology, China Medical University, Taichung 40402, Taiwan
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Immunodeficient mouse models with different disease profiles by in vivo infection with the same clinical isolate of enterovirus 71. J Virol 2014; 88:12485-99. [PMID: 25142603 DOI: 10.1128/jvi.00692-14] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
UNLABELLED Like poliovirus infection, severe infection with enterovirus 71 (EV71) can cause neuropathology. Unlike poliovirus, EV71 is often associated with hand-foot-and-mouth disease (HFMD). Here we established three mouse models for experimental infection with the same clinical isolate of EV71. The NOD/SCID mouse model is unique for the development of skin rash, an HFMD-like symptom. While the NOD/SCID mice developed limb paralysis and death at near-100% efficiency, the gamma interferon receptor knockout (ifngr KO) and stat-1 knockout mice exhibited paralysis and death rates near 78% and 30%, respectively. Productive infection with EV71 depends on the viral dose, host age, and inoculation route. Levels of infectious EV71, and levels of VP1-specific RNA and protein in muscle, brain, and spinal cord, were compared side by side between the NOD/SCID and stat-1 knockout models before, during, and after disease onset. Spleen fibrosis and muscle degeneration are common in the NOD/SCID and stat-1 knockout models. The main differences between these two models include their disease manifestations and cytokine/chemokine profiles. The pathology of the NOD/SCID model includes (i) inflammation and expression of viral VP1 antigen in muscle, (ii) increased neutrophil levels and decreased eosinophil and lymphocyte levels, and (iii) hair loss and skin rash. The characteristic pathology of the stat-1 knockout model includes (i) a strong tropism of EV71 for the central nervous system, (ii) detection of VP1 protein in the Purkinje layer of cerebellar cortex, pons, brain stem, and spinal cord, (iii) amplification of microglial cells, and (iv) dystrophy of intestinal villi. Our comparative studies on these new models with oral or intraperitoneal (i.p.) infection underscored the contribution of host immunity, including the gamma interferon receptor, to EV71 pathogenesis. IMPORTANCE In the past decade, enterovirus 71 (EV71) has emerged as a major threat to public health in the Asia-Pacific region. Disease manifestations include subclinical infection, common-cold-like syndromes, hand-foot-and-mouth disease (HFMD), uncomplicated brain stem encephalitis, severe dysregulation of the autonomic nerve system, fatal pulmonary edema, and cardiopulmonary collapse. To date, no effective vaccine or treatment is available. A user-friendly and widely accessible animal model for researching EV71 infection and pathogenesis is urgently needed by the global community, both in academia and in industry.
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Du N, Cong H, Tian H, Zhang H, Zhang W, Song L, Tien P. Cell surface vimentin is an attachment receptor for enterovirus 71. J Virol 2014; 88:5816-33. [PMID: 24623428 PMCID: PMC4019121 DOI: 10.1128/jvi.03826-13] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Accepted: 03/05/2014] [Indexed: 12/30/2022] Open
Abstract
UNLABELLED Enterovirus 71 (EV71) is a highly transmissible pathogenic agent that causes severe central nervous system diseases in infected infants and young children. Here, we reported that EV71 VP1 protein could bind to vimentin intermediate filaments expressed on the host cell surface. Soluble vimentin or an antibody against vimentin could inhibit the binding of EV71 to host cells. Accompanied with the reduction of vimentin expression on the cell surface, the binding of EV71 to cells was remarkably decreased. Further evidence showed that the N terminus of vimentin is responsible for the interaction between EV71 and vimentin. These results indicated that vimentin on the host cell surface may serve as an attachment site that mediated the initial binding and subsequently increased the infectivity of EV71. IMPORTANCE This study delivers important findings on the roles of vimentin filaments in relation to EV71 infection and provides information that not only improves our understanding of EV71 pathogenesis but also presents us with potentially new strategies for the treatment of diseases caused by EV71 infections.
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Affiliation(s)
- Ning Du
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
- University of the Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Haolong Cong
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Hongchao Tian
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
- Anhui University, Anhui, People's Republic of China
| | - Hua Zhang
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
- University of the Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Wenliang Zhang
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
- University of the Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Lei Song
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Po Tien
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
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Huang SW, Cheng HL, Hsieh HY, Chang CL, Tsai HP, Kuo PH, Wang SM, Liu CC, Su IJ, Wang JR. Mutations in the non-structural protein region contribute to intra-genotypic evolution of enterovirus 71. J Biomed Sci 2014; 21:33. [PMID: 24766641 PMCID: PMC4021180 DOI: 10.1186/1423-0127-21-33] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 04/11/2014] [Indexed: 12/03/2022] Open
Abstract
Background Clinical manifestations of enterovirus 71 (EV71) range from herpangina, hand-foot-and-mouth disease (HFMD), to severe neurological complications. Unlike the situation of switching genotypes seen in EV71 outbreaks during 1998–2008 in Taiwan, genotype B5 was responsible for two large outbreaks in 2008 and 2012, respectively. In China, by contrast, EV71 often persists as a single genotype in the population and causes frequent outbreaks. To investigate genetic changes in viral evolution, complete EV71 genome sequences were used to analyze the intra-genotypic evolution pattern in Taiwan, China, and the Netherlands. Results Genotype B5 was predominant in Taiwan’s 2008 outbreak and was re-emergent in 2012. EV71 strains from both outbreaks were phylogenetically segregated into two lineages containing fourteen non-synonymous substitutions predominantly in the non-structural protein coding region. In China, genotype C4 was first seen in 1998 and caused the latest large outbreak in 2008. Unlike shifting genotypes in Taiwan, genotype C4 persisted with progressive drift through time. A majority of non-synonymous mutations occurred in residues located in the non-structural coding region, showing annual increases. Interestingly, genotype B1/B2 in the Netherlands showed another stepwise evolution with dramatic EV71 activity increase in 1986. Phylogeny of the VP1 coding region in 1971–1986 exhibited similar lineage turnover with genotype C4 in China; however, phylogeny of the 3D-encoding region indicated separate lineage appearing after 1983, suggesting that the 3D-encoding region of genotype B2 was derived from an unidentified ancestor that contributed to intra-genotypic evolution in the Netherlands. Conclusions Unlike VP1 coding sequences long used for phylogenetic study of enteroviruses due to expected host immune escape, our study emphasizes a dominant role of non-synonymous mutations in non-structural protein regions that contribute to (re-)emergent genotypes in continuous stepwise evolution. Dozens of amino acid substitutions, especially in non-structural proteins, were identified via genetic changes driven through intra-genotypic evolution worldwide. These identified substitutions appeared to increase viral fitness in the population, affording valuable insights not only for viral evolution but also for prevention, control, and vaccine against EV71 infection.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Jen-Ren Wang
- Center of Infectious Disease and Signaling Research, National Cheng Kung University Hospital, Tainan, Taiwan.
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Wang YF, Yu CK. Animal models of enterovirus 71 infection: applications and limitations. J Biomed Sci 2014; 21:31. [PMID: 24742252 PMCID: PMC4013435 DOI: 10.1186/1423-0127-21-31] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Accepted: 04/11/2014] [Indexed: 01/06/2023] Open
Abstract
Human enterovirus 71 (EV71) has emerged as a neuroinvasive virus that is responsible for several outbreaks in the Asia-Pacific region over the past 15 years. Appropriate animal models are needed to understand EV71 neuropathogenesis better and to facilitate the development of effective vaccines and drugs. Non-human primate models have been used to characterize and evaluate the neurovirulence of EV71 after the early outbreaks in late 1990s. However, these models were not suitable for assessing the neurovirulence level of the virus and were associated with ethical and economic difficulties in terms of broad application. Several strategies have been applied to develop mouse models of EV71 infection, including strategies that employ virus adaption and immunodeficient hosts. Although these mouse models do not closely mimic human disease, they have been applied to determine the pathogenesis of and treatment and prevention of the disease. EV71 receptor-transgenic mouse models have recently been developed and have significantly advanced our understanding of the biological features of the virus and the host-parasite interactions. Overall, each of these models has advantages and disadvantages, and these models are differentially suited for studies of EV71 pathogenesis and/or the pre-clinical testing of antiviral drugs and vaccines. In this paper, we review the characteristics, applications and limitation of these EV71 animal models, including non-human primate and mouse models.
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Affiliation(s)
| | - Chun-Keung Yu
- Center of Infectious Disease and Signaling Research, Collage of Medicine, National Cheng Kung University, Tainan, Taiwan.
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Victorio CBL, Xu Y, Ng Q, Chow VTK, Chua KB. Phenotypic and genotypic characteristics of novel mouse cell line (NIH/3T3)-adapted human enterovirus 71 strains (EV71:TLLm and EV71:TLLmv). PLoS One 2014; 9:e92719. [PMID: 24671184 PMCID: PMC3966832 DOI: 10.1371/journal.pone.0092719] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 02/25/2014] [Indexed: 01/30/2023] Open
Abstract
Since its identification in 1969, Enterovirus 71 (EV71) has been causing periodic outbreaks of infection in children worldwide and most prominently in the Asia-Pacific Region. Understanding the pathogenesis of Enterovirus 71 (EV71) is hampered by the virus's inability to infect small animals and replicate in their derived in vitro cultured cells. This manuscript describes the phenotypic and genotypic characteristics of two selected EV71 strains (EV71:TLLm and EV71:TLLmv), which have been adapted to replicate in mouse-derived NIH/3T3 cells, in contrast to the original parental virus which is only able to replicate in primate cell lines. The EV71:TLLm strain exhibited productive infection in all primate and rodent cell lines tested, while EV71:TLLmv exhibited greater preference for mouse cell lines. EV71:TLLmv displayed higher degree of adaptation and temperature adaptability in NIH/3T3 cells than in Vero cells, suggesting much higher fitness in NIH/3T3 cells. In comparison with the parental EV71:BS strain, the adapted strains accumulated multiple adaptive mutations in the genome resulting in amino acid substitutions, most notably in the capsid-encoding region (P1) and viral RNA-dependent RNA polymerase (3D). Two mutations, E167D and L169F, were mapped to the VP1 canyon that binds the SCARB2 receptor on host cells. Another two mutations, S135T and K140I, were located in the VP2 neutralization epitope spanning amino acids 136-150. This is the first report of human EV71 with the ability to productively infect rodent cell lines in vitro.
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Affiliation(s)
- Carla Bianca Luena Victorio
- Temasek Lifesciences Laboratory, 1 Research Link, National University of Singapore, Singapore
- Host and Pathogen Interactivity Laboratory, Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore
| | - Yishi Xu
- Temasek Lifesciences Laboratory, 1 Research Link, National University of Singapore, Singapore
- Host and Pathogen Interactivity Laboratory, Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore
| | - Qimei Ng
- Temasek Lifesciences Laboratory, 1 Research Link, National University of Singapore, Singapore
| | - Vincent T. K. Chow
- Host and Pathogen Interactivity Laboratory, Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore
| | - Kaw Bing Chua
- Temasek Lifesciences Laboratory, 1 Research Link, National University of Singapore, Singapore
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Attenuation of human enterovirus 71 high-replication-fidelity variants in AG129 mice. J Virol 2014; 88:5803-15. [PMID: 24623423 DOI: 10.1128/jvi.00289-14] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
UNLABELLED In a screen for ribavirin resistance, a novel high-fidelity variant of human enterovirus 71 (EV71) with the single amino acid change L123F in its RNA-dependent RNA polymerase (RdRp or 3D) was identified. Based on the crystal structure of EV71 RdRp, L123 locates at the entrance of the RNA template binding channel, which might form a fidelity checkpoint. EV71 RdRp-L123F variants generated less progeny in a guanidine resistance assay and virus populations with lower mutation frequencies in cell culture passage due to their higher replication fidelity. However, compared with wild-type viruses, they did not show growth defects. In vivo infections further revealed that high-fidelity mutations L123F and G64R (previously reported) negatively impacted EV71 fitness and greatly reduced viral pathogenicity alone or together in AG129 mice. Interestingly, a variant with double mutations, RG/B4-G64R/L123F (where RG/B4 is an EV71 genotype B4 virus constructed by reverse genetics [RG])showed higher fidelity in vitro and less virulence in vivo than any one of the above two single mutants. The 50% lethal dose (LD50) of the double mutant increased more than 500 times compared with the LD50 of wild-type RG/B4 in mice. The results indicated that these high-fidelity variants exhibited an attenuated pathogenic phenotype in vivo and offer promise as a live attenuated EV71 vaccine. IMPORTANCE The error-prone nature of the RNA-dependent RNA polymerase (RdRp) of RNA viruses during replication results in quasispecies and aids survival of virus populations under a wide range of selective pressures. Virus variants with higher replication fidelity exhibit lower genetic diversity and attenuated pathogenicity in vivo. Here, we identified a novel high-fidelity mutation L123F in the RdRp of human enterovirus 71 (EV71). We further elucidated that EV71 variants with the RdRp-L123F mutation and/or the previously identified high-fidelity mutation RdRp-G64R were attenuated in an AG129 mouse model. As EV71 has emerged as a serious worldwide health threat, especially in developing countries in the Asia-Pacific region, we urgently need EV71 vaccines. Learning from the poliovirus vaccination, we prefer live attenuated EV71 vaccines to inactivated EV71 vaccines in order to effectively control EV71 outbreaks at low cost. Our results imply a new means of attenuating EV71 and reducing its mutation rate at the same time.
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50
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Lin JY, Shih SR. Cell and tissue tropism of enterovirus 71 and other enteroviruses infections. J Biomed Sci 2014; 21:18. [PMID: 24602216 PMCID: PMC3995930 DOI: 10.1186/1423-0127-21-18] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Accepted: 02/26/2014] [Indexed: 02/04/2023] Open
Abstract
Enterovirus 71 (EV71) is a member of Picornaviridae that causes mild and self-limiting hand, foot, and mouth disease (HFMD). However, EV71 infections can progress to polio-like paralysis, neurogenic pulmonary edema, and fatal encephalitis in infants and young children. Large EV71 outbreaks have been reported in Taiwan, China, Japan, Malaysia, Singapore, and Australia. This virus is considered a critical emerging public health threat. EV71 is an important crucial neurotropic enterovirus for which there is currently no effective antiviral drug or vaccine. The mechanism by which EV71 causes severe central nervous system complications remains unclear. The interaction between the virus and the host is vital for viral replication, virulence, and pathogenicity. SCARB2 or PSGL-1 receptor binding is the first step in the development of viral infections, and viral factors (e.g., 5' UTR, VP1, 3C, 3D, 3' UTR), host factors and environments (e.g., ITAFs, type I IFN) are also involved in viral infections. The tissue tropism and pathogenesis of viruses are determined by a combination of several factors. This review article provides a summary of host and virus factors affecting cell and tissue tropism and the pathogenesis of enteroviruses.
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Affiliation(s)
| | - Shin-Ru Shih
- Research Center for Emerging Viral Infections, Chang Gung University, Tao-Yuan, Taiwan.
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