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Liu H, Xue Q, Yang F, Cao W, Liu P, Liu X, Zhu Z, Zheng H. Foot-and-mouth disease virus VP1 degrades YTHDF2 through autophagy to regulate IRF3 activity for viral replication. Autophagy 2024; 20:1597-1615. [PMID: 38516932 PMCID: PMC11210904 DOI: 10.1080/15548627.2024.2330105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 03/09/2024] [Indexed: 03/23/2024] Open
Abstract
Many viruses, including foot-and-mouth disease virus (FMDV), can promote the degradation of host proteins through macroautophagy/autophagy, thereby promoting viral replication. However, the regulatory mechanism between autophagy and innate immune responses is not fully understood during FMDV infection. Here, we found that the host GTPBP4/NOG1 (GTP binding protein 4) is a negative regulator of innate immune responses. GTPBP4 deficiency promotes the antiviral innate immune response, resulting in the ability of GTPBP4 to promote FMDV replication. Meanwhile, GTPBP4-deficient mice are more resistant to FMDV infection. To antagonize the host's antiviral immunity, FMDV structural protein VP1 promotes the expression of GTPBP4, and the 209th site of VP1 is responsible for this effect. Mechanically, FMDV VP1 promotes autophagy during virus infection and interacts with and degrades YTHDF2 (YTH N6-methyladenosine RNA binding protein F2) in an AKT-MTOR-dependent autophagy pathway, resulting in an increase in GTPBP4 mRNA and protein levels. Increased GTPBP4 inhibits IRF3 binding to the Ifnb/Ifn-β promoter, suppressing FMDV-induced type I interferon production. In conclusion, our study revealed an underlying mechanism of how VP1 negatively regulates innate immunity through the autophagy pathway, which would contribute to understanding the negative regulation of host innate immune responses and the function of GTPBP4 and YTHDF2 during FMDV infection.Abbreviation: 3-MA:3-methyladenine; ACTB: actin beta; ATG: autophagy related; ChIP:chromatin immunoprecipitation; CQ: chloroquine; DAPI:4',6-diamidino-2-phenylindole; dpi: days post-infection; EV71:enterovirus 71; FMDV: foot-and-mouth disease virus; GTPBP4/NOG1: GTPbinding protein 4; HIF1A: hypoxia inducible factor 1 subunit alpha;hpt:hours post-transfection; IFNB/IFN-β:interferon beta; IRF3: interferon regulatory factor 3; MAP1LC3/LC3:microtubule associated protein 1 light chain 3; MAVS: mitochondriaantiviral signaling protein; MOI: multiplicity of infection; MTOR:mechanistic target of rapamycin kinase; m6A: N(6)-methyladenosine;qPCR:quantitativePCR; SIRT3:sirtuin 3; SQSTM1/p62: sequestosome 1; STING1: stimulator ofinterferon response cGAMP interactor 1; siRNA: small interfering RNA;TBK1: TANK binding kinase 1; TCID50:50% tissue culture infectious doses; ULK1: unc-51 like autophagyactivating kinase 1; UTR: untranslated region; WT: wild type; YTHDF2:YTH N6-methyladenosine RNA binding protein F2.
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Affiliation(s)
- Huisheng Liu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Qiao Xue
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Fan Yang
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Weijun Cao
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Pengfei Liu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xiangtao Liu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Zixiang Zhu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Haixue Zheng
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
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Hao J, Zhang X, Hu R, Lu X, Wang H, Li Y, Cheng K, Li Q. Metabolomics combined with network pharmacology reveals a role for astragaloside IV in inhibiting enterovirus 71 replication via PI3K-AKT signaling. J Transl Med 2024; 22:555. [PMID: 38858642 PMCID: PMC11163744 DOI: 10.1186/s12967-024-05355-9] [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: 04/07/2024] [Accepted: 05/29/2024] [Indexed: 06/12/2024] Open
Abstract
BACKGROUND Astragaloside IV (AST-IV), as an effective active ingredient of Astragalus membranaceus (Fisch.) Bunge. It has been found that AST-IV inhibits the replication of dengue virus, hepatitis B virus, adenovirus, and coxsackievirus B3. Enterovirus 71 (EV71) serves as the main pathogen in severe hand-foot-mouth disease (HFMD), but there are no specific drugs available. In this study, we focus on investigating whether AST-IV can inhibit EV71 replication and explore the potential underlying mechanisms. METHODS The GES-1 or RD cells were infected with EV71, treated with AST-IV, or co-treated with both EV71 and AST-IV. The EV71 structural protein VP1 levels, the viral titers in the supernatant were measured using western blot and 50% tissue culture infective dose (TCID50), respectively. Network pharmacology was used to predict possible pathways and targets for AST-IV to inhibit EV71 replication. Additionally, ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) was used to investigate the potential targeted metabolites of AST-IV. Associations between metabolites and apparent indicators were performed via Spearman's algorithm. RESULTS This study illustrated that AST-IV effectively inhibited EV71 replication. Network pharmacology suggested that AST-IV inhibits EV71 replication by targeting PI3K-AKT. Metabolomics results showed that AST-IV achieved these effects by elevating the levels of hypoxanthine, 2-ketobutyric acid, adenine, nicotinic acid mononucleotide, prostaglandin H2, 6-hydroxy-1 H-indole-3- acetamide, oxypurinol, while reducing the levels of PC (14:0/15:0). Furthermore, AST-IV also mitigated EV71-induced oxidative stress by reducing the levels of MDA, ROS, while increasing the activity of T-AOC, CAT, GSH-Px. The inhibition of EV71 replication was also observed when using the ROS inhibitor N-Acetylcysteine (NAC). Additionally, AST-IV exhibited the ability to activate the PI3K-AKT signaling pathway and suppress EV71-induced apoptosis. CONCLUSION This study suggests that AST-IV may activate the cAMP and the antioxidant stress response by targeting eight key metabolites, including hypoxanthine, 2-ketobutyric acid, adenine, nicotinic acid mononucleotide, prostaglandin H2, 6-Hydroxy-1 H-indole-3-acetamide, oxypurinol and PC (14:0/15:0). This activation can further stimulate the PI3K-AKT signaling to inhibit EV71-induced apoptosis and EV71 replication.
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Affiliation(s)
- JinFang Hao
- School of Pharmaceutical, Department of Laboratory Medicine of Fenyang College, Shanxi Medical University, Taiyuan, Shanxi Province, 030001, China
- Shanxi Key Laboratory of Innovative Drug for the Treatment of Serious Diseases Basing Chronic Inflammation, Shanxi University of Chinese Medicine, Jinzhong, 030619, China
- Medicinal Basic Research Innovation Center of Chronic Kidney Disease, Ministry of Education, Shanxi Medical University, Taiyuan, China
| | - Xiaoyan Zhang
- School of Pharmaceutical, Department of Laboratory Medicine of Fenyang College, Shanxi Medical University, Taiyuan, Shanxi Province, 030001, China.
| | - Ruixian Hu
- School of Pharmaceutical, Department of Laboratory Medicine of Fenyang College, Shanxi Medical University, Taiyuan, Shanxi Province, 030001, China
| | - Xiufeng Lu
- School of Pharmaceutical, Department of Laboratory Medicine of Fenyang College, Shanxi Medical University, Taiyuan, Shanxi Province, 030001, China
| | - Hui Wang
- School of Pharmaceutical, Department of Laboratory Medicine of Fenyang College, Shanxi Medical University, Taiyuan, Shanxi Province, 030001, China
| | - Yuanhong Li
- School of Pharmaceutical, Department of Laboratory Medicine of Fenyang College, Shanxi Medical University, Taiyuan, Shanxi Province, 030001, China
| | - Kai Cheng
- School of Pharmaceutical, Department of Laboratory Medicine of Fenyang College, Shanxi Medical University, Taiyuan, Shanxi Province, 030001, China
| | - Qingshan Li
- School of Pharmaceutical, Department of Laboratory Medicine of Fenyang College, Shanxi Medical University, Taiyuan, Shanxi Province, 030001, China.
- Shanxi Key Laboratory of Innovative Drug for the Treatment of Serious Diseases Basing Chronic Inflammation, Shanxi University of Chinese Medicine, Jinzhong, 030619, China.
- Medicinal Basic Research Innovation Center of Chronic Kidney Disease, Ministry of Education, Shanxi Medical University, Taiyuan, China.
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Liu H, Zhu Z, Xue Q, Yang F, Cao W, Xue Z, Liu X, Zheng H. Picornavirus infection enhances aspartate by the SLC38A8 transporter to promote viral replication. PLoS Pathog 2023; 19:e1011126. [PMID: 36735752 PMCID: PMC9931120 DOI: 10.1371/journal.ppat.1011126] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 02/15/2023] [Accepted: 01/17/2023] [Indexed: 02/04/2023] Open
Abstract
Foot-and-mouth disease, a class of animal diseases, is caused by foot-and-mouth disease virus (FMDV). The metabolic changes during FMDV infection remain unclear. Here, PK-15 cells, serum, and tonsils infected with FMDV were analyzed by metabolomics. A total of 284 metabolites in cells were significantly changed after FMDV infection, and most of them belong to amino acids and nucleotides. Further studies showed that FMDV infection significantly enhanced aspartate in vitro and in vivo. The amino acid transporter solute carrier family 38 member 8 (SLC38A8) was responsible for FMDV-upregulated aspartate. Enterovirus 71 (EV71) and Seneca Valley virus (SVV) infection also enhanced aspartate by SLC38A8. Aspartate aminotransferase activity was also elevated in FMDV-, EV71-, and SVV-infected cells, which may lead to reversible transition between the TCA cycle and amino acids synthesis. Aspartate and SLC38A8 were essential for FMDV, EV71, and SVV replication in cells. In addition, aspartate and SLC38A8 also promoted FMDV and EV71 replication in mice. Detailed analysis indicated that FMDV infection promoted the transfer of mTOR to lysosome to enhance interaction between mTOR and Rheb, and activated PI3K/AKT/TSC2/Rheb/mTOR/p70S6K1 pathway to promote viral replication. The mTORC1 signaling pathway was responsible for FMDV-induced SLC38A8 protein expression. For the first time, our data identified metabolic changes during FMDV infection. These data identified a novel mechanism used by FMDV to upregulate aspartate to promote viral replication and will provide new perspectives for developing new preventive strategies.
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Affiliation(s)
- Huisheng Liu
- State Key Laboratory of Veterinary Etiological Biology; College of Veterinary Medicine, Lanzhou University, WOAH/National reference laboratory for foot-and-mouth disease; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Zixiang Zhu
- State Key Laboratory of Veterinary Etiological Biology; College of Veterinary Medicine, Lanzhou University, WOAH/National reference laboratory for foot-and-mouth disease; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Qiao Xue
- State Key Laboratory of Veterinary Etiological Biology; College of Veterinary Medicine, Lanzhou University, WOAH/National reference laboratory for foot-and-mouth disease; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Fan Yang
- State Key Laboratory of Veterinary Etiological Biology; College of Veterinary Medicine, Lanzhou University, WOAH/National reference laboratory for foot-and-mouth disease; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Weijun Cao
- State Key Laboratory of Veterinary Etiological Biology; College of Veterinary Medicine, Lanzhou University, WOAH/National reference laboratory for foot-and-mouth disease; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Zhaoning Xue
- State Key Laboratory of Veterinary Etiological Biology; College of Veterinary Medicine, Lanzhou University, WOAH/National reference laboratory for foot-and-mouth disease; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xiangtao Liu
- State Key Laboratory of Veterinary Etiological Biology; College of Veterinary Medicine, Lanzhou University, WOAH/National reference laboratory for foot-and-mouth disease; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Haixue Zheng
- State Key Laboratory of Veterinary Etiological Biology; College of Veterinary Medicine, Lanzhou University, WOAH/National reference laboratory for foot-and-mouth disease; Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
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Kim S, Bae KS, Kim JH, Kang JH, Choi UY. Seroprevalence of Neutralizing Antibodies Against Candidate Serotypes of Enterovirus Vaccines Among Korean Children. Viral Immunol 2020; 34:62-67. [PMID: 33030408 DOI: 10.1089/vim.2020.0073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Hand, foot, and mouth disease (HFMD) is a pediatric public health concern in Asia. Surveillance data on the circulating serotypes of HFMD suggest that Enterovirus A71 (EV-A71) and coxsackieviruses A6, A10, and A16 (CVA6, CVA10, and CVA16) are the major serotypes causing HFMD. Asian countries, including Korea, are currently developing a multivalent vaccine targeting these serotypes. However, the immunity of children against specific serotypes, indicating past infection, should also be considered while selecting candidate serotypes for vaccine development. Therefore, we aimed to identify the age-stratified serological statuses of Korean children to determine candidate serotypes for HFMD vaccine development. This study included 220 participants, categorized into four age groups, 7 months-2 years, 3-5 years, 6-10 years, and 11-15 years. A neutralization test was performed to quantitate the neutralizing antibodies (NtAbs) in the sera of the participants. Only EV-A71 and CVA6 were found suitable as candidate serotypes for vaccine development, whereas further study is needed for CVA10 and CVA16. The highest seropositivity and NtAb titer ranges were observed for CVA6 in all age groups, suggesting that the participants had been predominantly exposed to CVA6. For EV-A71, seropositivity and NtAb titer ranges steadily increased with age, suggesting that children were currently exposed to EV-A71. For CVA10, the 3-5 years group showed the highest seropositivity rate and higher NtAb titer ranges than the older age groups, indicating that the exposure to CVA10 had mainly occurred in recent years. Future studies will identify whether the exposure to CVA10 was transient or will continue. For CVA16, seropositivity and NtAb titer ranges were generally low, indicating that only a few participants had been exposed to CVA16. We identified discrepancies between the sentinel surveillance data and our findings. This study provides a new perspective for HFMD vaccine development and policy making in Asian countries.
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Affiliation(s)
- Sol Kim
- Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Kil Seong Bae
- Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Department of Pediatrics, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jong-Hyun Kim
- Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jin Han Kang
- Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Ui Yoon Choi
- Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Department of Pediatrics, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
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Thanongsaksrikul J, Srimanote P, Tongtawe P, Glab-ampai K, Malik AA, Supasorn O, Chiawwit P, Poovorawan Y, Chaicumpa W. Identification and production of mouse scFv to specific epitope of enterovirus-71 virion protein-2 (VP2). Arch Virol 2018; 163:1141-1152. [DOI: 10.1007/s00705-018-3731-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 12/19/2017] [Indexed: 12/01/2022]
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Reyes M, Piotrowski M, Ang SK, Chan J, He S, Chu JJH, Kah JCY. Exploiting the Anti-Aggregation of Gold Nanostars for Rapid Detection of Hand, Foot, and Mouth Disease Causing Enterovirus 71 Using Surface-Enhanced Raman Spectroscopy. Anal Chem 2017; 89:5373-5381. [PMID: 28414218 DOI: 10.1021/acs.analchem.7b00066] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Enterovirus 71 (EV71) is a major public health threat that requires rapid point-of-care detection. Here, we developed a surface-enhanced Raman spectroscopy (SERS)-based scheme that utilized protein-induced aggregation of colloidal gold nanostars (AuNS) to rapidly detect EV71 without the need for fabricating a solid substrate, Raman labels or complicated sample handling. We used AuNS (hydrodynamic diameter, DH of 105.12 ± 1.13 nm) conjugated to recombinant scavenger receptor class B, member 2 (SCARB2) protein with known affinity to EV71. In the absence of EV71, AuNS-SCARB2 aggregated in biological media and produced four enhanced Raman peaks at 390, 510, 670, and 910 cm-1. In the presence of EV71, the three peaks at 510, 670, and 910 cm-1 disappeared, while the peak at 390 cm-1 diminished in intensity as the virus bound to AuNS-SCARB2 and prevented them from aggregation. These three peaks (510, 670, and 910 cm-1) were potential markers for specific detection of EV71 as their disappearance was not observable with a different dengue virus (DENV) as our control. Furthermore, the Raman measurements from colloidal SERS were more sensitive in probing the aggregation of AuNS-SCARB2 for detecting the presence of EV71 in protein-rich samples compared to UV-vis spectrum measurements. With this facile "anti-aggregation" approach, we were able to detect EV71 in protein-rich biological medium within 15 min with reasonable sensitivity of 107 pfu/mL and minimal sample preparation, making this translatable for point-of-care applications.
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Affiliation(s)
- Miguel Reyes
- Department of Materials Science and Engineering, National University of Singapore , 9 Engineering Drive 1, Blk EA, #03-09, Singapore 117575
| | - Marek Piotrowski
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences , Niezapominajek 8, 30-239 Krakow, Poland
- International Iberian Nanotechnology Laboratory , Avenida Mestre José Veiga, 4715-330 Braga, Portugal
| | - Swee Kim Ang
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore , 5 Science Drive 2, Blk MD4, Level 5, Singapore 117597
| | - Jingqi Chan
- Temasek Junior College , 22 Bedok South Road, Singapore 469278
| | - Shuai He
- Department of Biomedical Engineering, National University of Singapore , 4 Engineering Drive 3, Blk E4, #04-08, Singapore 117583
| | - Justin Jang Hann Chu
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore , 5 Science Drive 2, Blk MD4, Level 5, Singapore 117597
| | - James Chen Yong Kah
- Department of Biomedical Engineering, National University of Singapore , 4 Engineering Drive 3, Blk E4, #04-08, Singapore 117583
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Centre for Life Sciences (CeLS) , #05-01, 28 Medical Drive, Singapore 117456
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Chung WY, Chiang PS, Luo ST, Lin TY, Tsao KC, Lee MS. A Molecular Approach Applied to Enteroviruses Surveillance in Northern Taiwan, 2008-2012. PLoS One 2016; 11:e0167532. [PMID: 27907198 PMCID: PMC5131993 DOI: 10.1371/journal.pone.0167532] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 11/15/2016] [Indexed: 01/14/2023] Open
Abstract
Traditional methods for detection and serotyping of enterovirus infections are virus isolation and immunofluorescence assay (VI-IFA), which are labor-intensive and time-consuming. Recently, VP1 gene has been targeted to develop a CODEHOP-based RT-PCR (VP1-CODEHOP) for the same purpose. In this study, we conducted a 5-year enterovirus surveillance comparing the VI-IFA and VP1-CODEHOP tests. Throat swabs were collected from 431 pediatric patients and 208(48%) and 250(58%) were tested positive by the VI-IFA and VP1-CODEHOP tests, respectively. Among the 47 cases who had inconsistent results between the VI-IFA and VP1-CODEHOP tests and provided paired sera for serological verifications, correct diagnosis for the VI-IFA and VP1-CODEHOP were 5(11%) and 40(85%) cases, respectively. Therefore, the VP1-CODEHOP is more reliable for detection of human enteroviruses than the VI-IFA. Based on serological verifications for the eight cases who had inconsistent serotypes between the two tests and provided paired sera, five and two showed consistent serotypes with the VP1-CODEHOP and VI-IFA tests, respectively. CVA16, CVA6 and EV71 were the most prevalent serotypes in northern Taiwan, 2008~2012. Moreover, variant CVA2, CVA6 and EV71 viruses were further identified based on phylogenetic analysis of partial VP1 sequences. In conclusion, the VP1-CODEHOP test could be used as the primary method for enterovirus surveillance to support decision-making for outbreak control.
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Affiliation(s)
- Wan-Yu Chung
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes (NHRI), Zhunan Town, Miaoli County, Taiwan
| | - Pai-Shan Chiang
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes (NHRI), Zhunan Town, Miaoli County, Taiwan
| | - Shu-Ting Luo
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes (NHRI), Zhunan Town, Miaoli County, Taiwan
| | - Tzou-Yien Lin
- Department of Pediatrics, Chang Gung Memorial Hospital, Guishan Dist, Taoyuan City, Taiwan
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Guishan Dist, Taoyuan City, Taiwan
| | - Kuo-Chien Tsao
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Guishan Dist, Taoyuan City, Taiwan
- Department of Clinical Pathology, Chang Gung Memorial Hospital, Guishan Dist, Taoyuan City, Taiwan
| | - Min-Shi Lee
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes (NHRI), Zhunan Town, Miaoli County, Taiwan
- * E-mail:
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Chen P, Wu X, Mao Q, Gao F, Hao X, Bian L, Zhu F, Li W, Xu M, Liang Z. A rapid and quantitative assay for measuring neutralizing antibodies of Coxsackievirus B3. J Virol Methods 2016; 232:1-7. [PMID: 26947399 PMCID: PMC7113863 DOI: 10.1016/j.jviromet.2016.02.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 02/17/2016] [Accepted: 02/19/2016] [Indexed: 11/17/2022]
Abstract
We have established a robust single round infection system of CVB3. A new quantitative assay for measuring NtAb of CVB3 in clinical samples. Seroprevalence of CVB3 in pre-school children is lower than that in adults.
Coxsackievirus B3 (CVB3) infection has been found to account for an increasing proportion cases of hand, foot and mouth disease (HFMD) in recent epidemiology studies. CVB3 is a single stranded, non-enveloped RNA virus and the infection can cause prominent health threat to pre-school children. Here, by taking approaches of reverse genetics, we established a single-round infection system for CVB3. The pseudovirus was produced by sequential transfection of CVB3 capsid expresser plasmid and CVB3 replicon RNA bearing firefly luciferase as a reporter. The CVB3 pseudovirus system was used for quantifying neutralizing antibody (NtAb) levels of 720 human serum samples and showed superior specificity and sensitivity comparing traditional cytopathic effect (CPE) assay. Furthermore, we compared the seroprevalence of CVB3 NtAbs in pre-school children and healthy adults, and found that only 11.94% of pre-school children were NtAbs positive which suggested that most children were naive to CVB3 infection; while there is much higher positive rate in adults (60%) indicating that most adults have experienced CVB3 infection during childhood. This rapid and quantitative assay greatly facilitates evaluating the level of NtAbs against CVB3 in populations and will help to advance CVB3 vaccine development.
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Affiliation(s)
- Pan Chen
- National Institutes for Food and Drug Control, Beijing 100050, China; National Institute of Biological Sciences, Beijing 102206, China
| | - Xing Wu
- National Institutes for Food and Drug Control, Beijing 100050, China
| | - Qunying Mao
- National Institutes for Food and Drug Control, Beijing 100050, China
| | - Fan Gao
- National Institutes for Food and Drug Control, Beijing 100050, China
| | - Xiaotian Hao
- National Institutes for Food and Drug Control, Beijing 100050, China
| | - Lianlian Bian
- National Institutes for Food and Drug Control, Beijing 100050, China
| | - Fengcai Zhu
- Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210009, China
| | - Wenhui Li
- National Institute of Biological Sciences, Beijing 102206, China
| | - Miao Xu
- National Institutes for Food and Drug Control, Beijing 100050, China
| | - Zhenglun Liang
- National Institutes for Food and Drug Control, Beijing 100050, China.
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Reemergence of enterovirus 71 epidemic in northern Taiwan, 2012. PLoS One 2015; 10:e0116322. [PMID: 25774888 PMCID: PMC4361668 DOI: 10.1371/journal.pone.0116322] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 12/08/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Enterovirus 71 (EV71) belongs to picornavirus family and could be classified phylogenetically into three major genogroups (A, B and C) including 11 genotypes (A, B1-B5 and C1-C5). Since 1997, EV71 has caused large-scale of epidemics with neurological complications in Asian children. In Taiwan, nationwide EV71 epidemics with different predominant genotypes have occurred cyclically since 1998. A nationwide EV71 epidemic occurred again in 2012. We conducted genetic and antigenic characterizations of the 2012 epidemic. METHODS Chang Gung Memorial Hospital (CGMH) is a medical center in northern Taiwan. In CGMH, specimens were collected from pediatric inpatients with suspected enterovirus infections for virus isolation. Enterovirus isolates were serotyped and genotyped and sera from EV71 inpatients were collected for measuring neutralizing antibody titers. RESULTS There were 10, 16 and 99 EV71 inpatients identified in 2010, 2011 and 2012, respectively. There were 82 EV71 isolates genotyped, which identified 17 genotype C4a viruses and 65 genotype B5 viruses. The genotype B5 viruses were not detected until November 2011 and caused epidemics in 2012. Interestingly, the B5-2011 viruses were genetically distinguishable from the B5 viruses causing the 2008 epidemic and are likely introduced from China or Southeastern Asia. Based on antigenic analysis, minor antigenic variations were detected among the B5-2008, B5-2011, C4a-2008 and C4a-2012 viruses but these viruses antigenically differed from genotype A. CONCLUSIONS Genotype B5 and C4a viruses antigenically differ from genotype A viruses which have disappeared globally for 30 years but have been detected in China since 2008. Enterovirus surveillance should monitor genetic and antigenic variations of EV71.
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Hou W, Yang L, He D, Zheng J, Xu L, Liu J, Liu Y, Zhao H, Ye X, Cheng T, Xia N. Development of a coxsackievirus A16 neutralization test based on the enzyme-linked immunospot assay. J Virol Methods 2015; 215-216:56-60. [PMID: 25704596 DOI: 10.1016/j.jviromet.2015.02.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 12/17/2014] [Accepted: 02/11/2015] [Indexed: 01/16/2023]
Abstract
Coxsackievirus A16 (CA16) is one of the major pathogens responsible for hand, foot and mouth disease (HFMD). The assessment of the humoral immunity response is indispensable in the development of vaccines against enteroviruses. The neutralization test based on the inhibition of cytopathic effects (Nt-CPE) is a common method for measuring neutralizing antibodies against CA16. However, an efficient neutralization test needs to be developed for seroepidemiological surveys and clinical trials of CA16 vaccines because Nt-CPE is time-consuming and labor-intensive. In this study, a high-throughput neutralization test for CA16 based on the enzyme-linked immunospot assay (Nt-ELISPOT) was developed. The monoclonal antibody 7D10, which reacted with the viral protein VP1, was used to detect the cells infected with CA16. The neutralizing titers of sera were proven to be unchanged over an infectious dose range from 10 to 10,000TCID50 per well. The Nt-ELISPOT results correlated well with the Nt-CPE results (R(2) = 0.9250), and the detection period was shortened from five days to approximately 30h. Overall, the Nt-ELISPOT is a reliable and efficient method for measuring neutralizing antibodies against CA16.
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Affiliation(s)
- Wangheng Hou
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Lisheng Yang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Delei He
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Jun Zheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Longfa Xu
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jian Liu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Yajing Liu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Huan Zhao
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Xiangzhong Ye
- Beijing Wantai Biological Pharmacy Enterprise Co., Ltd., Beijing, 102206, China
| | - Tong Cheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen, 361102, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen 361102, China.
| | - Ningshao Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen, 361102, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen 361102, China
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Chia MY, Chung WY, Chiang PS, Chien YS, Ho MS, Lee MS. Monitoring antigenic variations of enterovirus 71: implications for virus surveillance and vaccine development. PLoS Negl Trop Dis 2014; 8:e3044. [PMID: 25058733 PMCID: PMC4109910 DOI: 10.1371/journal.pntd.0003044] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 06/11/2014] [Indexed: 01/18/2023] Open
Abstract
Enterovirus 71 (EV71) causes life-threatening epidemics in Asia and can be phylogenetically classified into three major genogroups (A ∼ C) including 11 genotypes (A, B1 ∼ B5, and C1 ∼ C5). Recently, EV71 epidemics occurred cyclically in Taiwan with different genotypes. In recent years, human studies using post-infection sera obtained from children have detected antigenic variations among different EV71 strains. Therefore, surveillance of enterovirus 71 should include phylogenetic and antigenic analysis. Due to limitation of sera available from children with EV71 primary infection, suitable animal models should be developed to generate a panel of antisera for monitoring EV71 antigenic variations. Twelve reference strains representing the 11 EV71 genotypes were grown in rhabdomyosarcoma cells. Infectious EV71 particles were purified and collected to immunize rabbits. The rabbit antisera were then employed to measure neutralizing antibody titers against the 12 reference strains and 5 recent strains. Rabbits immunized with genogroup B and C viruses consistently have a lower neutralizing antibody titers against genogroup A (≧ 8-fold difference) and antigenic variations between genogroup B and C viruses can be detected but did not have a clear pattern, which are consistent with previous human studies. Comparison between human and rabbit neutralizing antibody profiles, the results showed that ≧ 8-fold difference in rabbit cross-reactive antibody ratios could be used to screen EV71 isolates for identifying potential antigenic variants. In conclusion, a rabbit model was developed to monitor antigenic variations of EV71, which are critical to select vaccine strains and predict epidemics.
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Affiliation(s)
- Min-Yuan Chia
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan
| | - Wan-Yu Chung
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan
| | - Pai-Shan Chiang
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan
| | - Yeh-Sheng Chien
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan
| | - Mei-Shang Ho
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Min-Shi Lee
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan
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12
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Yang L, He D, Tang M, Li Z, Liu C, Xu L, Chen Y, Du H, Zhao Q, Zhang J, Cheng T, Xia N. Development of an enzyme-linked immunosorbent spot assay to measure serum-neutralizing antibodies against coxsackievirus B3. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2014; 21:312-20. [PMID: 24391137 PMCID: PMC3957675 DOI: 10.1128/cvi.00359-13] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Accepted: 12/23/2013] [Indexed: 11/20/2022]
Abstract
Coxsackievirus B3 (CVB3) is the most common pathogen that induces acute and chronic viral myocarditis in children. The cytopathic effect (CPE)-based neutralization test (Nt-CPE) and the plaque reduction neutralization test (PRNT) are the most common methods for measuring neutralizing antibody titers against CVB3 in blood serum samples. However, these two methods are inefficient for CVB3 vaccine clinical trials, which require the testing of a large number of serum specimens. In this study, we developed an efficient neutralization test based on the enzyme-linked immunospot (Nt-ELISPOT) assay for measuring CVB3-neutralizing antibodies. This modified ELISPOT assay was based on the use of a monoclonal antibody against the viral capsid protein VP1 to detect the cells that are infected with CVB3, which, after immunoperoxidase staining, are counted as spots using an automated ELISPOT analyzer. Using the modified ELISPOT assay, we characterized the infection kinetics of CVB3 and divided the infection process of CVB3 on a cluster of cells into four phases. The stability of the Nt-ELISPOT was then evaluated. We found that over a wide range of infectious doses (10(2) to 10(6.5)× 50% tissue culture infectious dose [TCID(50)] per well), the neutralizing titers of the sera were steady as long as they were tested during the log phase or the first half of the stationary phase of growth of the spots. We successfully shortened the testing period from 7 days to approximately 20 h. We also found that there was a good correlation (R(2) = 0.9462) between the Nt-ELISPOT and the Nt-CPE assays. Overall, the Nt-ELISPOT assay is a reliable and efficient method for measuring neutralizing antibodies in serum.
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13
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Eschbaumer M, Law S, Solis C, Chernick A, van der Meer F, Czub M. Rapid detection of neutralizing antibodies against bovine viral diarrhoea virus using quantitative high-content screening. J Virol Methods 2014; 198:56-63. [DOI: 10.1016/j.jviromet.2013.12.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 11/26/2013] [Accepted: 12/17/2013] [Indexed: 11/29/2022]
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Linsuwanon P, Puenpa J, Huang SW, Wang YF, Mauleekoonphairoj J, Wang JR, Poovorawan Y. Epidemiology and seroepidemiology of human enterovirus 71 among Thai populations. J Biomed Sci 2014; 21:16. [PMID: 24548776 PMCID: PMC3937078 DOI: 10.1186/1423-0127-21-16] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 02/09/2014] [Indexed: 11/23/2022] Open
Abstract
Background Human enterovirus 71 (EV71) is an important pathogen caused large outbreaks in Asian-Pacific region with severe neurological complications and may lead to death in young children. Understanding of the etiological spectrum and epidemic changes of enterovirus and population’s immunity against EV71 are crucial for the implementation of future therapeutic and prophylactic intervention. Results A total of 1,182 patients who presented with the symptoms of hand foot and mouth disease (67.3%) or herpangina (HA) (16.7%) and admitted to the hospitals during 2008-2013 were tested for enterovirus using pan-enterovirus PCR targeting 5′-untranslated region and specific PCR for viral capsid protein 1 gene. Overall, 59.7% were pan-enterovirus positive comprising 9.1% EV71 and 31.2% coxsackievirus species A (CV-A) including 70.5% CV-A6, 27.6% CV-A16, 1.1% CV-A10, and 0.8% CV-A5. HFMD and HA occurred endemically during 2008-2011. The number of cases increased dramatically in June 2012 with the percentage of the recently emerged CV-A6 significantly rose to 28.4%. Co-circulation between different EV71 genotypes was observed during the outbreak. Total of 161 sera obtained from healthy individuals were tested for neutralizing antibodies (NAb) against EV71 subgenotype B5 (EV71-B5) using microneutralization assay. The seropositive rate of EV71-B5 was 65.8%. The age-adjusted seroprevalence for individuals was found to be lowest in children aged >6 months to 2 years (42.5%). The seropositive rate remained relatively low in preschool children aged > 2 years to 6 years (48.3%) and thereafter increased sharply to more than 80% in individuals aged > 6 years. Conclusions This study describes longitudinal data reflecting changing patterns of enterovirus prevalence over 6 years and demonstrates high seroprevalences of EV71-B5 NAb among Thai individuals. The rate of EV71 seropositive increased with age but without gender-specific significant difference. We identified that relative lower EV71 seropositive rate in early 2012 may demonstrate widely presented of EV71-B5 in the population before account for a large outbreak scale epidemic occurred in 2012 with due to a relatively high susceptibility of the younger population.
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Affiliation(s)
| | | | | | | | | | | | - Yong Poovorawan
- Center of Excellence in Clinical Virology, Department of Pediatric, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand.
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Jrad-Battikh N, Souii A, Oueslati L, Aouni M, Hober D, Gharbi J, Ben M'hadheb-Gharbi M. Neutralizing activity induced by the attenuated coxsackievirus B3 Sabin3-like strain against CVB3 infection. Curr Microbiol 2013; 68:503-9. [PMID: 24322405 DOI: 10.1007/s00284-013-0498-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 10/07/2013] [Indexed: 11/26/2022]
Abstract
Coxsackievirus B3 (CVB3) causes viral myocarditis, and can ultimately result in dilated cardiomyopathy. There is no vaccine available for clinical use. In the present work, we assessed whether the Sabin3-like mutant of CVB3 could induce a protective immunity against virulent CVB3 Nancy and CVB4 E2 strains in mice by both oral and intraperitoneal (IP) routes. Serum samples, taken from mice inoculated with Sabin3-like, were assayed in vitro for their anti-CVB3 neutralizing activity. CVB3 Sabin3-like was highly attenuated in vivo and was able to induce an anti-CVB3 activity of the serum. However, at 4 days post-CVB3 challenge, significant increased titers of CVB3 neutralizing antibodies were detectable in the sera of immunized mice over the next 6 days. Non-immunized mice challenged with CVB3 Nancy had no anti-CVB3 activity in their sera until 10 days post-infection. CVB3 Nancy induced higher viral titers than did the mutant strain. There was no variation of the neutralizing activity of serum taken from mice immunized with CVB3 Sabin3-like and challenged with CVB4 E2, compared to non-immunized mice. Despite the fact that CVB3 and CVB4 are closely related viruses, virus-neutralizing activity clearly distinguish between these viruses. A variable and limited amount of pancreatic inflammation was seen in some mice 10 days after Sabin3-like inoculation by IP route, whereas there was no evidence of pancreatic damage in mice inoculated by oral route. All immunized mice were protected from myocarditis and pancreatitis at 8 days post-challenge with CVB3 or CVB4 E2. These findings strongly suggest that the mutant strain could be considered a candidate for an attenuated CVB3 vaccine.
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Affiliation(s)
- Nadia Jrad-Battikh
- Laboratoire des Maladies Transmissibles et Substances Biologiquement Actives (LR99-ES27), Faculté de Pharmacie de Monastir, Avenue Avicenne, 5000, Biotola, Tunisia
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16
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Wu X, Mao Q, Yao X, Chen P, Chen X, Shao J, Gao F, Yu X, Zhu F, Li R, Li W, Liang Z, Wang J, Lu F. Development and evaluation of a pseudovirus-luciferase assay for rapid and quantitative detection of neutralizing antibodies against enterovirus 71. PLoS One 2013; 8:e64116. [PMID: 23755115 PMCID: PMC3673970 DOI: 10.1371/journal.pone.0064116] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 04/09/2013] [Indexed: 11/21/2022] Open
Abstract
The level of neutralizing antibodies (NtAb) induced by vaccine inoculation is an important endpoint to evaluate the efficacy of EV71 vaccine. In order to evaluate the efficacy of EV71 vaccine, here, we reported the development of a novel pseudovirus system expression firefly luciferase (PVLA) for the quantitative measurement of NtAb. We first evaluated and validated the sensitivity and specificity of the PVLA method. A total of 326 serum samples from an epidemiological survey and 144 serum specimens from 3 clinical trials of EV71 vaccines were used, and the level of each specimen's neutralizing antibodies (NtAb) was measured in parallel using both the conventional CPE-based and PVLA-based assay. Against the standard neutralization assay based on the inhibition of the cytopathic effect (CPE), the sensitivity and specificity of the PVLA method are 98% and 96%, respectively. Then, we tested the potential interference of NtAb against hepatitis A virus, Polio-I, Polio-II, and Polio-III standard antisera (WHO) and goat anti-G10/CA16 serum, the PVLA based assay showed no cross-reactivity with NtAb against other specific sera. Importantly, unlike CPE based method, no live replication-competent EV71 is used during the measurement. Taken together, PVLA is a rapid and specific assay with higher sensitivity and accuracy. It could serve as a valuable tool in assessing the efficacy of EV71 vaccines in clinical trials and disease surveillance in epidemiology studies.
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MESH Headings
- Antibodies, Neutralizing/blood
- Antibodies, Viral/blood
- Cell Line, Tumor
- Child, Preschool
- Clinical Trials as Topic
- Enterovirus A, Human/immunology
- Enterovirus A, Human/physiology
- Female
- Hand, Foot and Mouth Disease/immunology
- Hand, Foot and Mouth Disease/prevention & control
- Hand, Foot and Mouth Disease/virology
- Humans
- Infant
- Luciferases, Firefly/biosynthesis
- Male
- Neutralization Tests
- Reproducibility of Results
- Sensitivity and Specificity
- Vaccination
- Viral Vaccines/immunology
- Virus Internalization
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Affiliation(s)
- Xing Wu
- Department of Microbiology and Infectious Disease Center, Peking University Health Science Center, Beijing, China
- Department of Hepatitis Vaccine, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Qunying Mao
- Department of Hepatitis Vaccine, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Xin Yao
- Department of Hepatitis Vaccine, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Pan Chen
- National Institute of Biological Sciences, Beijing, China
| | - Xiangmei Chen
- Department of Microbiology and Infectious Disease Center, Peking University Health Science Center, Beijing, China
| | - Jie Shao
- Department of Hepatitis Vaccine, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Fan Gao
- Department of Hepatitis Vaccine, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Xiang Yu
- Hualan Biological Engineering Inc. , Henan, China
| | - Fengcai Zhu
- Jiangsu Provincial Center for Disease Prevention and Control, Nanjing, China
| | - Rongcheng Li
- The Center for Disease Control and Prevention of the Guangxi Zhuang Automomous Region, Nanning, China
| | - Wenhui Li
- National Institute of Biological Sciences, Beijing, China
| | - Zhenglun Liang
- Department of Hepatitis Vaccine, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
- * E-mail: (FML); (ZLL)
| | - Junzhi Wang
- Department of Hepatitis Vaccine, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Fengmin Lu
- Department of Microbiology and Infectious Disease Center, Peking University Health Science Center, Beijing, China
- * E-mail: (FML); (ZLL)
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Cross-reactive neutralizing antibody responses to enterovirus 71 infections in young children: implications for vaccine development. PLoS Negl Trop Dis 2013; 7:e2067. [PMID: 23459633 PMCID: PMC3573098 DOI: 10.1371/journal.pntd.0002067] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 01/04/2013] [Indexed: 12/13/2022] Open
Abstract
Background Recently, enterovirus 71 (EV71) has caused life-threatening outbreaks involving neurological and cardiopulmonary complications in Asian children with unknown mechanism. EV71 has one single serotype but can be phylogenetically classified into 3 main genogroups (A, B and C) and 11 genotypes (A, B1∼B5 and C1∼C5). In Taiwan, nationwide EV71 epidemics with different predominant genotypes occurred in 1998 (C2), 2000–2001 (B4), 2004–2005 (C4), and 2008 (B5). In this study, sera were collected to measure cross-reactive neutralizing antibody titers against different genotypes. Methods We collected historical sera from children who developed an EV71 infection in 1998, 2000, 2005, 2008, or 2010 and measured cross-reactive neutralizing antibody titers against all 11 EV71 genotypes. In addition, we aligned and compared the amino acid sequences of P1 proteins of the tested viruses. Results Serology data showed that children infected with genogroups B and C consistently have lower neutralizing antibody titers against genogroup A (>4-fold difference). The sequence comparisons revealed that five amino acid signatures (N143D in VP2; K18R, H116Y, D167E, and S275A in VP1) are specific for genogroup A and may be related to the observed antigenic variations. Conclusions This study documented antigenic variations among different EV71 genogroups and identified potential immunodominant amino acid positions. Enterovirus surveillance and vaccine development should monitor these positions. Recently, enterovirus 71 (EV71) has caused life-threatening outbreaks in tropical Asia. EV71 has one single serotype but can be phylogenetically classified into 3 main genogroups and 11 genotypes (A, B1∼B5 and C1∼C5). In Taiwan, nationwide EV71 epidemics with different predominant genotypes occurred in 1998(C2), 2000–2001(B4), 2004–2005(C4), and 2008(B5). In this study, historical sera from children infected with these 4 genotypes were collected to measure cross-reactive neutralizing antibody titers against 11 genotypes. In addition, amino acid sequences of P1 proteins of the tested viruses were compared. Serology data showed that children infected with genogroup B and C consistently have lower neutralizing antibody titers against genogroup A (>4-fold difference). Antigenic variations between genogroup B and C could be detected but did not have a clear pattern. Five amino acid signatures are specific for genogroup A and may be related to the observed antigenic variations. Vaccine development should monitor the antigenic and genetic variations to select vaccine strains.
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Reactogenicity and immunogenicity of an enterovirus 71 vaccine in Chinese healthy children and infants. Pediatr Infect Dis J 2012; 31:1158-65. [PMID: 22926209 DOI: 10.1097/inf.0b013e31826eba74] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Enterovirus 71 (EV71) is highly contagious and can cause severe complications. A safe and effective vaccine is needed. We assessed the reactogenicity and immunogenicity of an inactivated, alum-adjuvanted EV71 vaccine in this study. METHODS A randomized, double-blind, placebo-controlled clinical trial was undertaken in 360 healthy participants who were stratified into 2 age groups (6-12 and 13-60 months), and randomly allocated to receive placebo or the investigational vaccine containing 160 U, 320 U or 640 U antigen per dose by the ratio of 1:1:1:1 at days 0 and 28. Reactogenic data within 28 days after each vaccination were recorded. Blood samples were obtained on days 0, 28 and 56 for neutralizing antibody assay. RESULTS Overall, 193 participants reported at least 1 injection-site or systemic adverse reaction with 53.3% and 54.4% participants receiving the study vaccine and placebo, respectively. Most of the reactions were mild or moderate. Three serious adverse events were observed, but none was related to vaccination. In the participants with seronegative baseline, after 2 doses all the participants receiving EV71 vaccines were seropositive and the seroconversion rates were more than 98.1%. In the participants with seropositive baseline, 1 dose induced good seroconversion rates of more than 64.3% in participants receiving EV71 vaccines. CONCLUSIONS This study found that the inactivated EV71 vaccine was well tolerated and had good immunogenicity in healthy children and infants. A single dose induced typical booster response in the participants with a seropositive baseline, and 2 doses were needed for the immunologically naive participants.
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Chiang PS, Huang ML, Luo ST, Lin TY, Tsao KC, Lee MS. Comparing molecular methods for early detection and serotyping of enteroviruses in throat swabs of pediatric patients. PLoS One 2012; 7:e48269. [PMID: 23133580 PMCID: PMC3484998 DOI: 10.1371/journal.pone.0048269] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2012] [Accepted: 09/21/2012] [Indexed: 01/29/2023] Open
Abstract
Background Enteroviruses include over 100 serotypes and usually cause self-limited infections with non-specific symptoms in children, with the exceptions of polioviruses and enterovirus 71 which frequently cause neurologic complications. Therefore, early detection and serotyping of enteroviruses are critical in clinical management and disease surveillance. Traditional methods for detection and serotyping of enteroviruses are virus isolation and immunofluorescence assay, which are time-consuming. In this study, we compare virus isolation and two molecular tests for detection and serotyping of enteroviruses in clinical samples. Methods One hundred and ten throat swabs were collected from pediatric outpatients with enterovirus-like illnesses (hand-foot-mouth disease, herpangina, and non-specific febrile illness). Virus isolation was conducted using multiple cell lines and isolated viruses were serotyped using immunofluorescent assay. In the molecular tests, a semi-nested RT-PCR and a novel CODEHOP platform were used to detect the 5′UTR and VP1 genes of enteroviruses, respectively. Amplified nucleotides were sequenced and genotyped. Results Among the 110 cases, 39(35%), 52(47%), and 46(42%) were tested positive with these three tests, respectively. Using the consensus results of these three tests as the gold standard, agreement of the VP1 CODEHOP test was 96%, which is higher than those of the virus isolation (89%) and the 5′-UTR test (88%). The VP1 CODEHOP test also has the best performance on serotyping confirmed with serum neutralization tests. Conclusions The VP1 CODEHOP test performed well for detection and serotyping of enteroviruses in clinical specimens and could reduce unnecessary hospitalization cares during enterovirus seasons.
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Affiliation(s)
- Pai-Shan Chiang
- National Institutes of Infectious Diseases and Vaccinology, National Health Research Institutes, Taiwan
| | - Mei-Liang Huang
- National Institutes of Infectious Diseases and Vaccinology, National Health Research Institutes, Taiwan
| | - Shu-Ting Luo
- National Institutes of Infectious Diseases and Vaccinology, National Health Research Institutes, Taiwan
| | - Tzou-Yien Lin
- Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Kuo-Chien Tsao
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Taoyuan, Taiwan
- Department of Clinical Pathology, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Min-Shi Lee
- National Institutes of Infectious Diseases and Vaccinology, National Health Research Institutes, Taiwan
- * E-mail:
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20
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Zhu FC, Liang ZL, Meng FY, Zeng Y, Mao QY, Chu K, Song XF, Yao X, Li JX, Ji H, Zhang YJ, Li L, Pan HX, Xu K, Dai WM, Zhang WW, Deng F, Wang H, Wang JZ. Retrospective study of the incidence of HFMD and seroepidemiology of antibodies against EV71 and CoxA16 in prenatal women and their infants. PLoS One 2012; 7:e37206. [PMID: 22662137 PMCID: PMC3360679 DOI: 10.1371/journal.pone.0037206] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 04/17/2012] [Indexed: 11/19/2022] Open
Abstract
Background Hand, foot, and mouth disease (HFMD) has been emerging as an important public problem over the past few decades, especially in Asian and Pacific regions. A national program on EV71 vaccine development against HFMD was initiated in China, in 2008, which called for a need for seroepidemiological study for the target population. Methodology/Principal Findings This was a retrospective study conducted in Jiangsu Province, in October, 2010. We measured the neutralizing antibodies against EV71 and CoxA16 in a cohort of infants aged of 2, 7, 12, and 27–38 months and their mothers just before delivery. Series sera samples from 975 infants and 555 mothers were collected and analyzed. Questionnaires on the history of HFMD were completed in the survey. A total of 143 HFMD cases were collected, but only 11.2% were reported to the National Infectious Disease Information Management System. The level of maternal antibody titers decreased dramatically during the first 7 month and remained at a relatively low level thereafter. But it increased significantly from month 12 to months 27–38. The accumulate incidence density of HFMD demonstrated a significant increase after 14 months of age, resulting in a accumulate incidence density of 50.8/1000 person-years in survey period. Seropositivity of EV71 antibody in infants at the age of 2 months seems to demonstrate a protective effect against HFMD. Conclusions and Significance High seropositive rate of EV71 and CoxA16 antibody was found in prenatal women in mainland China, and there is a need to enhance the HFMD case management and the current surveillance system. We suggest that infants aged between 6 to 14 months should have the first priority to receive EV71 vaccine.
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Affiliation(s)
- Feng-Cai Zhu
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
- * E-mail: (J-ZW); (F-CZ); (Z-LL)
| | - Zheng-Lun Liang
- Laboratory 2, National Institutes for Food and Drug Control, Beijing, People’s Republic of China
- * E-mail: (J-ZW); (F-CZ); (Z-LL)
| | - Fan-Yue Meng
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Ying Zeng
- Shenzhen Kangtai Biological Products Co., Ltd., Shenzhen Science & Industry Park, Guangdong Province, People’s Republic of China
| | - Qun-Ying Mao
- Laboratory 2, National Institutes for Food and Drug Control, Beijing, People’s Republic of China
| | - Kai Chu
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Xue-Fang Song
- Shenzhen Kangtai Biological Products Co., Ltd., Shenzhen Science & Industry Park, Guangdong Province, People’s Republic of China
| | - Xin Yao
- Laboratory 2, National Institutes for Food and Drug Control, Beijing, People’s Republic of China
| | - Jing-Xin Li
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Hong Ji
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Yi-Ju Zhang
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Liang Li
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Hong-Xing Pan
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Ke Xu
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Wei-Ming Dai
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Wei-Wei Zhang
- School of Public Health, Southeast University, Nanjing, Jiangsu Province, People’s Republic of China
| | - Fei Deng
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Hua Wang
- Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
| | - Jun-Zhi Wang
- Laboratory 2, National Institutes for Food and Drug Control, Beijing, People’s Republic of China
- * E-mail: (J-ZW); (F-CZ); (Z-LL)
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Lee MS, Chiang PS, Luo ST, Huang ML, Liou GY, Tsao KC, Lin TY. Incidence rates of enterovirus 71 infections in young children during a nationwide epidemic in Taiwan, 2008-09. PLoS Negl Trop Dis 2012; 6:e1476. [PMID: 22348156 PMCID: PMC3279337 DOI: 10.1371/journal.pntd.0001476] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 12/03/2011] [Indexed: 11/18/2022] Open
Abstract
Objective Enterovirus 71 (EV71) is causing life-threatening outbreaks in tropical Asia. In Taiwan and other tropical Asian countries, although nationwide EV71 epidemics occur cyclically, age-specific incidence rates of EV71 infections that are critical to estimate disease burden and design vaccine trials are not clear. A nationwide EV71 epidemic occurred in 2008–09 in Taiwan, which provided a unique opportunity to estimate age-specific incidence rates of EV71 infections. Study Design We prospectively recruited 749 healthy neonates and conducted follow-ups from June 2006 to December 2009. Sera were obtained from participants at 0, 6, 12, 24, and 36 months of age for measuring EV71 neutralizing antibody titers. If the participants developed suspected enterovirus illnesses, throat swabs were collected for virus isolation. Results We detected 28 EV71 infections including 20 symptomatic and 8 asymptomatic infections. Age-specific incidence rates of EV71 infection increased from 1.71 per 100 person-years at 0–6 months of age to 4.09, 5.74, and 4.97 per 100 person-years at 7–12, 13–24, and 25–36 months of age, respectively. Cumulative incidence rate was 15.15 per 100 persons by 36 months of age, respectively. Conclusions Risk of EV71 infections in Taiwan increased after 6 months of age during EV71 epidemics. The cumulative incidence rate was 15% by 36 months of age, and 29% of EV71 infections were asymptomatic in young children. Enterovirus 71 (EV71) was first isolated in California, USA, in 1969. Since then, EV71 has been identified globally. Recently, EV71 caused several life-threatening outbreaks in young children in tropical Asia. Development of EV71 vaccines becomes national priority in several Asia countries including Taiwan. To design clinical trials of EV71 vaccines, age-specific incidence rates of EV71 infections are required to identify target populations, estimate disease burdens, select endpoints of clinical efficacy, and estimate sample size. In Taiwan, nationwide EV71 epidemics occurred every 3–4 years but age-specific incidences of EV71 infection are not available. In 2006, we initiated a prospective cohort study in northern Taiwan to recruit neonates and follow up them. In 2008–09, a nationwide EV71 epidemic occurred and we found that age-specific incidence rates of EV71 infection increased from 1.71 per 100 person-years at 0–6 months of age to 4.09, 5.74, and 4.97 per 100 person-years at 7–12, 13–24, and 25–36 months of age, respectively. The cumulative incidence rate was 15% by 36 months of age, and 29% of EV71 infections were asymptomatic in young children. These findings would be helpful to development of EV71 vaccines in Taiwan and other Asian tropical countries.
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Affiliation(s)
- Min-Shi Lee
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan.
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22
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Annexin II binds to capsid protein VP1 of enterovirus 71 and enhances viral infectivity. J Virol 2011; 85:11809-20. [PMID: 21900167 DOI: 10.1128/jvi.00297-11] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Enterovirus type 71 (EV71) causes hand, foot, and mouth disease (HFMD), which is mostly self-limited but may be complicated with a severe to fatal neurological syndrome in some children. Understanding the molecular basis of virus-host interactions might help clarify the largely unknown neuropathogenic mechanisms of EV71. In this study, we showed that human annexin II (Anx2) protein could bind to the EV71 virion via the capsid protein VP1. Either pretreatment of EV71 with soluble recombinant Anx2 or pretreatment of host cells with an anti-Anx2 antibody could result in reduced viral attachment to the cell surface and a reduction of the subsequent virus yield in vitro. HepG2 cells, which do not express Anx2, remained permissive to EV71 infection, though the virus yield was lower than that for a cognate lineage expressing Anx2. Stable transfection of plasmids expressing Anx2 protein into HepG2 cells (HepG2-Anx2 cells) could enhance EV71 infectivity, with an increased virus yield, especially at a low infective dose, and the enhanced infectivity could be reversed by pretreating HepG2-Anx2 cells with an anti-Anx2 antibody. The Anx2-interacting domain was mapped by yeast two-hybrid analysis to VP1 amino acids 40 to 100, a region different from the known receptor binding domain on the surface of the picornavirus virion. Our data suggest that binding of EV71 to Anx2 on the cell surface can enhance viral entry and infectivity, especially at a low infective dose.
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Yang C, Deng C, Wan J, Zhu L, Leng Q. Neutralizing antibody response in the patients with hand, foot and mouth disease to enterovirus 71 and its clinical implications. Virol J 2011; 8:306. [PMID: 21679417 PMCID: PMC3142239 DOI: 10.1186/1743-422x-8-306] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Accepted: 06/16/2011] [Indexed: 11/13/2022] Open
Abstract
Enterovirus 71 (EV71) has emerged as a significant pathogen causing large outbreaks in China for the past 3 years. Developing an EV71 vaccine is urgently needed to stop the spread of the disease; however, the adaptive immune response of humans to EV71 infection remains unclear. We examined the neutralizing antibody titers in HFMD patients and compared them to those of asymptomatic healthy children and young adults. We found that 80% of HFMD patients became positive for neutralizing antibodies against EV71 (GMT = 24.3) one day after the onset of illness. The antibody titers in the patients peaked two days (GMT = 79.5) after the illness appeared and were comparable to the level of adults (GMT = 45.2). Noticeably, the antibody response was not correlated with disease severity, suggesting that cellular immune response, besides neutralizing antibodies, could play critical role in controlling the outcome of EV71 infection in humans.
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Affiliation(s)
- Chunfu Yang
- Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, 225 South Chongqing Road, Shanghai 200025, PR China
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Lee MS, Lin TY, Chiang PS, Li WC, Luo ST, Tsao KC, Liou GY, Huang ML, Hsia SH, Huang YC, Chang SC. An investigation of epidemic enterovirus 71 infection in Taiwan, 2008: clinical, virologic, and serologic features. Pediatr Infect Dis J 2010; 29:1030-4. [PMID: 20543760 DOI: 10.1097/inf.0b013e3181e52945] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Enterovirus 71 (EV71) is causing life-threatening hand-foot-mouth disease in Asia. In Taiwan, EV71 epidemics with different predominant genotypes occurred in 1998 (C2), 2000-2001 (B4), and 2004-2005 (C4). This genotype replacement may have important implications for vaccine development and prediction of epidemics. A nationwide EV71 outbreak occurred again in 2008, which provided a unique opportunity to characterize clinical, virologic, and serologic features of this epidemic. METHODS We analyzed clinical and virologic data of 111 EV71 patients hospitalized in 2008 and prospectively conducted follow-ups of healthy children from June 2006 to December 2008. RESULTS Among the 111 EV71 inpatients, 21 (19%) developed complications. Among the 21 complicated cases, 15 had central nervous system complication only, 2 had acute heart failure, and 4 had central nervous system and pulmonary complications. In the prospective study, 11 symptomatic infections and 4 asymptomatic infections were detected. Twenty-two EV71 isolates were genotyped, and 21 of them belong to genotype B5, which is phylogenetically close to B5 viruses circulating in Southeast Asia. Serologic tests show that children infected with B5 viruses have lower geometric mean titers of neutralizing antibody against genotype C4 than those against genotype B5 (P = 0.004, t test). CONCLUSIONS The 2008 nationwide EV71 epidemic was caused by genotype B5 that was likely introduced to Taiwan from Southeast Asia. Clinical features of the 2008 epidemic were not different from those observed before in Taiwan. Potential antigenic variations between genotype C4 and B5 viruses could be detected and its long-term epidemiologic significance needs further investigation to clarify.
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Affiliation(s)
- Min-Shi Lee
- Division of Infectious Diseases, National Health Research Institutes (NHRI), Zhunan, Miaoli County, Taiwan.
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