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Watts DM, Rodriguez CM, Palermo PM, Suarez V, Wong SJ, Orbegozo J, Dupuis AP, Kramer LD, Gonzalez FJ, Handel GA. Serosurvey for dengue virus infection among pregnant women in the West Nile virus enzootic community of El Paso Texas. PLoS One 2020; 15:e0242889. [PMID: 33253280 PMCID: PMC7703982 DOI: 10.1371/journal.pone.0242889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 11/10/2020] [Indexed: 01/14/2023] Open
Abstract
All 4 dengue viruses (DENV) cause sporadic outbreaks of human disease in the Rio Grande Valley along the US-Mexico border. In addition, West Nile virus (WNV) is enzootic in most border communities, and is the only arbovirus known to cause human disease in the El Paso, Texas community. In an effort to determine if DENV were also endemic in the El Paso community, a serosurvey was conducted among mothers at the time of delivery of their babies in selected hospitals. Cord-blood plasma samples obtained from mothers were tested for DENV antibody by an enzyme-linked immuno-sorbent assay (ELISA), plaque reduction neutralization test (PRNT) and a multiplex microsphere immunoassay. All DENV antibody positive plasma samples were also tested for WNV antibody by the same assays to consider the possibility that DENV antibody positive samples reflected WNV cross reactive antibody. The results indicated that 0.74% (11/1,472) of the mothers had a previous DENV infection and that 3.3% (48/1,472) had a previous WNV infection. Of these mothers, 0.20% (3/1,472) had antibody to both DENV and WNV as evidence of infection by both viruses. The results indicated that 0.2% (3/1472) of the mothers were positive for antibody to only WNV envelope, thus suggesting an undetermined flavivirus infection. Although 6 of the 11 DENV antibody positive mothers did not have a history of travel to a DENV endemic country, the findings of this survey provided further evidence of local transmission of WNV and suggested the possibility of focal autochthonous transmission of DENV in the El Paso community.
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Affiliation(s)
- Douglas M. Watts
- Department of Biological Science, University of Texas at El Paso, El Paso, Texas, United States of America
| | - Cynthia M. Rodriguez
- Department of Biological Science, University of Texas at El Paso, El Paso, Texas, United States of America
| | - Pedro M. Palermo
- Department of Biological Science, University of Texas at El Paso, El Paso, Texas, United States of America
| | - Veronica Suarez
- Department of Biological Science, University of Texas at El Paso, El Paso, Texas, United States of America
| | - Susan J. Wong
- Diagnostic Immunology Laboratory, Wadsworth Center, New York State Department of Health, Albany, NY, United States of America
| | - Jeanette Orbegozo
- Department of Biological Science, University of Texas at El Paso, El Paso, Texas, United States of America
| | - Alan P. Dupuis
- Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY, United States of America
| | - Laura D. Kramer
- Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY, United States of America
| | | | - Gilbert A. Handel
- Paul L. Foster School of Medicine, El Paso, Texas, United States of America
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Granger D, Leo YS, Lee LK, Theel ES. Serodiagnosis of dengue virus infection using commercially available antibody and NS1 antigen ELISAs. Diagn Microbiol Infect Dis 2017; 88:120-124. [PMID: 28389145 DOI: 10.1016/j.diagmicrobio.2017.03.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 03/23/2017] [Accepted: 03/27/2017] [Indexed: 11/27/2022]
Abstract
Accuracy of the InBios DENV Detect IgM, IgG and NS1 antigen (Ag) ELISAs (Seattle, WA) for detection of dengue virus (DENV) infection were evaluated using 100 retrospectively selected sera from acutely febrile patients presenting to a Singapore hospital. The InBios DENV NS1, IgM and IgG ELISAs had an overall sensitivity of 83.6%, 40% and 58.2% and an overall specificity of 97.8%, 97.8% and 55.6%, respectively. Simultaneous testing for NS1 and IgM-antibodies yielded a sensitivity and specificity of 85.5% and 95.5%, respectively, which did not significantly differ from testing for NS1 Ag alone. Using sera positive for IgM- or IgG-class antibodies to six common arboviruses, the InBios IgM and IgG ELISAs showed an overall analytic specificity of 89.2% and 66.4%, respectively. This study suggests that recent DENV infection can reliably be detected by the InBios NS1 Ag ELISA alone and that InBios DENV IgG reactivity should be interpreted with caution.
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Affiliation(s)
- D Granger
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Y S Leo
- Institute of Infectious Diseases and Epidemiology, Communicable Disease Centre, Tan Tock Seng Hospital, Singapore
| | - L K Lee
- Institute of Infectious Diseases and Epidemiology, Communicable Disease Centre, Tan Tock Seng Hospital, Singapore
| | - E S Theel
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
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Kariwa H, Murata R, Totani M, Yoshii K, Takashima I. Increased pathogenicity of West Nile virus (WNV) by glycosylation of envelope protein and seroprevalence of WNV in wild birds in Far Eastern Russia. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2013; 10:7144-64. [PMID: 24351738 PMCID: PMC3881158 DOI: 10.3390/ijerph10127144] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/25/2013] [Accepted: 11/26/2013] [Indexed: 01/28/2023]
Abstract
In this review, we discuss the possibility that the glycosylation of West Nile (WN) virus E-protein may be associated with enhanced pathogenicity and higher replication of WN virus. The results indicate that E-protein glycosylation allows the virus to multiply in a heat-stable manner and therefore, has a critical role in enhanced viremic levels and virulence of WN virus in young-chick infection model. The effect of the glycosylation of the E protein on the pathogenicity of WN virus in young chicks was further investigated. The results indicate that glycosylation of the WN virus E protein is important for viral multiplication in peripheral organs and that it is associated with the strong pathogenicity of WN virus in birds. The micro-focus reduction neutralization test (FRNT) in which a large number of serum samples can be handled at once with a small volume (15 μL) of serum was useful for differential diagnosis between Japanese encephalitis and WN virus infections in infected chicks. Serological investigation was performed among wild birds in the Far Eastern region of Russia using the FRNT. Antibodies specific to WN virus were detected in 21 samples of resident and migratory birds out of 145 wild bird samples in the region.
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Affiliation(s)
- Hiroaki Kariwa
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-Ku, Sapporo 060-0818, Japan; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +81-11-706-5211; Fax: +81-11-706-5211
| | - Ryo Murata
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-Ku, Sapporo 060-0818, Japan; E-Mail:
- Laboratory of Animal Health, Department of Animal Science, Faculty of Agriculture, Tokyo University of Agriculture, Funako 1737, Atsugi 243-0034, Japan; E-Mail:
| | - Masashi Totani
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-Ku, Sapporo 060-0818, Japan; E-Mail:
- Third Animal Quarantine Division, Animal Quarantine Service, Narita Branch, Ministry of Agriculture, Forestry and Fisheries, Ohaza Tennami, Sanrizuka, Aza Nishihara 254-1, Narita 282-0011, Japan; E-Mail:
| | - Kentaro Yoshii
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-Ku, Sapporo 060-0818, Japan; E-Mail:
| | - Ikuo Takashima
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-Ku, Sapporo 060-0818, Japan; E-Mail:
- Department of Nutrition, Faculty of Nursing and Nutrition, Tenshi College, Kita-13, Higashi-3-1-30, Higashi-Ku, Sapporo 065-0013, Japan; E-Mail:
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Beck C, Jimenez-Clavero MA, Leblond A, Durand B, Nowotny N, Leparc-Goffart I, Zientara S, Jourdain E, Lecollinet S. Flaviviruses in Europe: complex circulation patterns and their consequences for the diagnosis and control of West Nile disease. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2013; 10:6049-83. [PMID: 24225644 PMCID: PMC3863887 DOI: 10.3390/ijerph10116049] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 10/24/2013] [Accepted: 10/29/2013] [Indexed: 12/11/2022]
Abstract
In Europe, many flaviviruses are endemic (West Nile, Usutu, tick-borne encephalitis viruses) or occasionally imported (dengue, yellow fever viruses). Due to the temporal and geographical co-circulation of flaviviruses in Europe, flavivirus differentiation by diagnostic tests is crucial in the adaptation of surveillance and control efforts. Serological diagnosis of flavivirus infections is complicated by the antigenic similarities among the Flavivirus genus. Indeed, most flavivirus antibodies are directed against the highly immunogenic envelope protein, which contains both flavivirus cross-reactive and virus-specific epitopes. Serological assay results should thus be interpreted with care and confirmed by comparative neutralization tests using a panel of viruses known to circulate in Europe. However, antibody cross-reactivity could be advantageous in efforts to control emerging flaviviruses because it ensures partial cross-protection. In contrast, it might also facilitate subsequent diseases, through a phenomenon called antibody-dependent enhancement mainly described for dengue virus infections. Here, we review the serological methods commonly used in WNV diagnosis and surveillance in Europe. By examining past and current epidemiological situations in different European countries, we present the challenges involved in interpreting flavivirus serological tests and setting up appropriate surveillance programs; we also address the consequences of flavivirus circulation and vaccination for host immunity.
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Affiliation(s)
- Cécile Beck
- UMR1161 Virologie INRA, ANSES, ENVA, EU-RL on equine West Nile disease, Animal Health Laboratory, ANSES, Maisons-Alfort 94704, France; E-Mails: (C.B.); (S.Z.)
| | | | - Agnès Leblond
- Département Hippique, VetAgroSup, Marcy l’Etoile 69280, France; E-Mail:
- UR346, INRA, Saint Genès Champanelle 63122, France; E-Mail:
| | - Benoît Durand
- Epidemiology Unit, Animal Health Laboratory, ANSES, Maisons-Alfort 94704, France; E-Mail:
| | - Norbert Nowotny
- Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine Vienna, Vienna 1210, Austria; E-Mail:
- Department of Microbiology and Immunology, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat 123, Sultanate of Oman
| | | | - Stéphan Zientara
- UMR1161 Virologie INRA, ANSES, ENVA, EU-RL on equine West Nile disease, Animal Health Laboratory, ANSES, Maisons-Alfort 94704, France; E-Mails: (C.B.); (S.Z.)
| | - Elsa Jourdain
- UR346, INRA, Saint Genès Champanelle 63122, France; E-Mail:
| | - Sylvie Lecollinet
- UMR1161 Virologie INRA, ANSES, ENVA, EU-RL on equine West Nile disease, Animal Health Laboratory, ANSES, Maisons-Alfort 94704, France; E-Mails: (C.B.); (S.Z.)
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Garg H, Lee RTC, Tek NO, Maurer-Stroh S, Joshi A. Identification of conserved motifs in the West Nile virus envelope essential for particle secretion. BMC Microbiol 2013; 13:197. [PMID: 24007503 PMCID: PMC3766686 DOI: 10.1186/1471-2180-13-197] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 08/27/2013] [Indexed: 12/31/2022] Open
Abstract
Background Enveloped viruses utilize cellular membranes to bud from infected cells. The process of virion assembly and budding is often facilitated by the presence of certain conserved motifs within viral proteins in conjunction with cellular factors. We hence examined the West Nile Virus (WNV) Envelope protein for the presence of any such motifs and their functional characterization. Results We identified conserved 461PXAP464 and 349YCYL352 motifs in the WNV envelope glycoprotein bearing resemblance to retroviral late domains. Disruptive mutations of PXAP to LAAL and of the highly conserved Cys350 in the YCYL motif, led to a severe reduction in WNV particle production. Similar motifs in case of retroviruses are known to interact with components of host sorting machinery like PXAP with Tsg101 and YXXL with Alix. However, in the case of WNV, siRNA mediated depletion of Alix or Tsg101 did not have an effect on WNV release. Molecular modeling suggested that while the 461PXAP464 motif is surface accessible and could potentially interact with cellular proteins required for WNV assembly, the 349YCYL352 motif was found to be internal with Cys350 important for protein folding via disulphide bonding. Conclusions The conserved 461PXAP464 and 349YCYL352 motifs in the WNV envelope are indispensable for WNV particle production. Although these motifs bear sequence similarity to retroviral late domains and are essential for WNV assembly, they are functionally distinct suggesting that they are not the typical late domain like motifs of retroviruses and may play a role other than Alix/Tsg101 utilization/dependence.
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Affiliation(s)
- Himanshu Garg
- Department of Biomedical Sciences, Texas Tech University Health Sciences Center, 5001 El Paso Dr, MSB-1 Annex, El Paso, TX 79905, USA.
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Li L, An H, Sun M, Dong J, Yuan J, Hu Q. Identification and genomic analysis of two duck-origin Tembusu virus strains in southern China. Virus Genes 2012; 45:105-12. [PMID: 22581444 DOI: 10.1007/s11262-012-0753-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 04/25/2012] [Indexed: 10/28/2022]
Abstract
Egg-laying duck flocks in Guangdong province, southern China, have been suffering a widely spreading infectious disease with abrupt egg drops and death since the winter of 2010. However, the causative pathogen was not known. We obtained two independent virus isolates named FS and JM from the diseased layer duck flocks and identified them as duck-origin Tembusu virus by PCR detection, sequencing the entire length of the open reading frames (ORFs). The two isolates FS and JM shared high sequence similarity to the isolates of duck-origin Tembusu virus that was first emerged in eastern China in April 2010. Blast analysis shows that the whole ORF sequences of FS and JM have the highest similarity (>99 %) to BYD-1(the first reported duck-origin Tembusu virus) and JS804 (the first reported goose-origin Tembusu virus), indicating that the full-length genomes were highly conserved in waterfowl-origin Tembusu viruses. The present study suggests that duck-origin Tembusu viruses have spread fast from eastern China to southern China, causing widely spreading infections. The high conservation of duck-origin Tembusu virus strains provides the genomic basis for choosing the strains for vaccine preparation for better protection against this new virus infection.
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Affiliation(s)
- Linlin Li
- Guangdong Open Laboratory of Veterinary Public Health, Institute of Veterinary Medicine, Guangdong Academy of Agricultural Sciences, Baishigang Road, Tianhe, Guangzhou 510640, People's Republic of China
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Papa A, Karabaxoglou D, Kansouzidou A. Acute West Nile virus neuroinvasive infections: cross-reactivity with dengue virus and tick-borne encephalitis virus. J Med Virol 2012; 83:1861-5. [PMID: 21837806 DOI: 10.1002/jmv.22180] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Cross-reactions in serology are common among flaviviruses. During the outbreak of West Nile virus (WNV) infections in Greece in 2010, WNV IgM-positive serum and cerebrospinal fluid samples were tested for the presence of IgM and IgG antibodies against Dengue virus (DENV) and tick-borne encephalitis virus. Higher cross-reactivity was observed in IgM antibodies between WNV and DENV; however, the index of the WNV antibodies was in all cases higher than that of the DENV antibodies. There is a need for caution when evaluating serologic results of flaviviral infections, while efforts have to be focused on the development of diagnostic assays with increased specificity.
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Affiliation(s)
- Anna Papa
- Department of Microbiology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece.
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Totani M, Yoshii K, Kariwa H, Takashima I. Glycosylation of the Envelope Protein of West Nile Virus Affects Its Replication in Chicks. Avian Dis 2011; 55:561-8. [DOI: 10.1637/9743-032811-reg.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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9
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Murata R, Eshita Y, Maeda A, Maeda J, Akita S, Tanaka T, Yoshii K, Kariwa H, Umemura T, Takashima I. Glycosylation of the West Nile Virus envelope protein increases in vivo and in vitro viral multiplication in birds. Am J Trop Med Hyg 2010; 82:696-704. [PMID: 20348522 DOI: 10.4269/ajtmh.2010.09-0262] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Many West Nile (WN) virus isolates associated with significant outbreaks possess a glycosylation site on the envelope (E) protein. E-protein glycosylated variants of New York (NY) strains of WN virus are more neuroinvasive in mice than the non-glycosylated variants. To determine how E protein glycosylation affects the interactions between WN virus and avian hosts, we inoculated young chicks with NY strains of WN virus containing either glycosylated or non-glycosylated variants of the E protein. The glycosylated variants were more virulent and had higher viremic levels than the non-glycosylated variants. The glycosylation status of the variant did not affect viral multiplication and dissemination in mosquitoes in vivo. Glycosylated variants showed more heat-stable propagation than non-glycosylated variants in mammalian (BHK) and avian (QT6) cells but not in mosquito (C6/36) cells. Thus, E-protein glycosylation may be a requirement for efficient transmission of WN virus from avian hosts to mosquito vectors.
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Affiliation(s)
- Ryo Murata
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
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Seligman SJ. Constancy and diversity in the flavivirus fusion peptide. Virol J 2008; 5:27. [PMID: 18275613 PMCID: PMC2275255 DOI: 10.1186/1743-422x-5-27] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Accepted: 02/14/2008] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Flaviviruses include the mosquito-borne dengue, Japanese encephalitis, yellow fever and West Nile and the tick-borne encephalitis viruses. They are responsible for considerable world-wide morbidity and mortality. Viral entry is mediated by a conserved fusion peptide containing 16 amino acids located in domain II of the envelope protein E. Highly orchestrated conformational changes initiated by exposure to acidic pH accompany the fusion process and are important factors limiting amino acid changes in the fusion peptide that still permit fusion with host cell membranes in both arthropod and vertebrate hosts. The cell-fusing related agents, growing only in mosquitoes or insect cell lines, possess a different homologous peptide. RESULTS Analysis of 46 named flaviviruses deposited in the Entrez Nucleotides database extended the constancy in the canonical fusion peptide sequences of mosquito-borne, tick-borne and viruses with no known vector to include more recently-sequenced viruses. The mosquito-borne signature amino acid, G104, was also found in flaviviruses with no known vector and with the cell-fusion related viruses. Despite the constancy in the canonical sequences in pathogenic flaviviruses, mutations were surprisingly frequent with a 27% prevalence of nonsynonymous mutations in yellow fever virus fusion peptide sequences, and 0 to 7.4% prevalence in the others. Six of seven yellow fever patients whose virus had fusion peptide mutations died. In the cell-fusing related agents, not enough sequences have been deposited to estimate reliably the prevalence of fusion peptide mutations. However, the canonical sequences homologous to the fusion peptide and the pattern of disulfide linkages in protein E differed significantly from the other flaviviruses. CONCLUSION The constancy of the canonical fusion peptide sequences in the arthropod-borne flaviviruses contrasts with the high prevalence of mutations in most individual viruses. The discrepancy may be the result of a survival advantage accompanying sequence diversity (quasispecies) involving the fusion peptide. Limited clinical data with yellow fever virus suggest that the presence of fusion peptide mutants is not associated with a decreased case fatality rate. The cell-fusing related agents may have substantial differences from other flaviviruses in their mechanism of viral entry into the host cell.
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Affiliation(s)
- Stephen J Seligman
- Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, USA.
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Schein CH, Zhou B, Braun W. Stereophysicochemical variability plots highlight conserved antigenic areas in Flaviviruses. Virol J 2005; 2:40. [PMID: 15845145 PMCID: PMC1112618 DOI: 10.1186/1743-422x-2-40] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2005] [Accepted: 04/21/2005] [Indexed: 11/18/2022] Open
Abstract
Background Flaviviruses, which include Dengue (DV) and West Nile (WN), mutate in response to immune system pressure. Identifying escape mutants, variant progeny that replicate in the presence of neutralizing antibodies, is a common way to identify functionally important residues of viral proteins. However, the mutations typically occur at variable positions on the viral surface that are not essential for viral replication. Methods are needed to determine the true targets of the neutralizing antibodies. Results Stereophysicochemical variability plots (SVPs), 3-D images of protein structures colored according to variability, as determined by our PCPMer program, were used to visualize residues conserved in their physical chemical properties (PCPs) near escape mutant positions. The analysis showed 1) that escape mutations in the flavivirus envelope protein are variable residues by our criteria and 2) two escape mutants found at the same position in many flaviviruses sit above clusters of conserved residues from different regions of the linear sequence. Conservation patterns in T-cell epitopes in the NS3- protease suggest a similar mechanism of immune system evasion. Conclusion The SVPs add another dimension to structurally defining the binding sites of neutralizing antibodies. They provide a useful aid for determining antigenically important regions and designing vaccines.
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Affiliation(s)
- Catherine H Schein
- Sealy Center for Structural Biology, Department of Human Biology, Chemistry and Genetics, University of Texas Medical Branch at Galveston, TX, USA
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, TX, USA
| | - Bin Zhou
- Sealy Center for Structural Biology, Department of Human Biology, Chemistry and Genetics, University of Texas Medical Branch at Galveston, TX, USA
| | - Werner Braun
- Sealy Center for Structural Biology, Department of Human Biology, Chemistry and Genetics, University of Texas Medical Branch at Galveston, TX, USA
- Sealy Center for Vaccine Development, Department of Human Biology, Chemistry and Genetics, University of Texas Medical Branch at Galveston, TX, USA
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Shirato K, Miyoshi H, Goto A, Ako Y, Ueki T, Kariwa H, Takashima I. Viral envelope protein glycosylation is a molecular determinant of the neuroinvasiveness of the New York strain of West Nile virus. J Gen Virol 2004; 85:3637-3645. [PMID: 15557236 DOI: 10.1099/vir.0.80247-0] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Two New York (NY) strains of the West Nile (WN) virus were plaque-purified and four variants that had different amino acid sequences at the N-linked glycosylation site in the envelope (E) protein sequence were isolated. The E protein was glycosylated in only two of these strain variants. To determine the relationship between E protein glycosylation and pathogenicity of the WN virus, 6-week-old mice were infected subcutaneously with these variants. Mice infected with viruses that carried the glycosylated E protein developed lethal infection, whereas mice infected with viruses that carried the non-glycosylated E protein showed low mortality. In contrast, intracerebral infection of mice with viruses carrying either the glycosylated or non-glycosylated forms of the E protein resulted in lethal infection. These results suggested that E protein glycosylation is a molecular determinant of neuroinvasiveness in the NY strains of WN virus.
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Affiliation(s)
- Kazuya Shirato
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Hirotsugu Miyoshi
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Akiko Goto
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Yoshihiko Ako
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Tomotaka Ueki
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Hiroaki Kariwa
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Ikuo Takashima
- Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
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Hogrefe WR, Moore R, Lape-Nixon M, Wagner M, Prince HE. Performance of immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assays using a West Nile virus recombinant antigen (preM/E) for detection of West Nile virus- and other flavivirus-specific antibodies. J Clin Microbiol 2004; 42:4641-8. [PMID: 15472323 PMCID: PMC522294 DOI: 10.1128/jcm.42.10.4641-4648.2004] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2004] [Revised: 03/26/2004] [Accepted: 06/23/2004] [Indexed: 11/20/2022] Open
Abstract
Focus Technologies developed an indirect immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) and a mu-capture IgM ELISA for the detection of West Nile virus (WNV)-specific antibodies based on a WNV preM/E protein recombinant antigen. Normal and disease state serum panels were used to assess the performance characteristics of the two WNV ELISA kits. Totals of 807 and 1,423 sera were used to assess the IgG ELISA and IgM ELISA kits, respectively. The Focus Technologies IgG ELISA had a sensitivity of 97.6% and a specificity of 92.1% (excluding non-WNV flavivirus sera). The comparative method for WNV IgG may lack sensitivity in detecting IgG in early WNV infection, so the specificity of the Focus IgG ELISA may be higher than 92.1%. When sera from patients either infected with or vaccinated against other flaviviruses were tested on the WNV IgG assay, 35% of the sera reacted as positive for WNV IgG. Yellow fever and Japanese encephalitis vaccinees were less reactive in the IgG ELISA than St. Louis and dengue fever patients. The Focus Technologies IgM ELISA had a sensitivity and a specificity of 99.3% (excluding the non-WNV flavivirus sera). The overall cross-reactivity for the IgM ELISA to flavivirus sera was 12%, with 31% of St. Louis encephalitis patients found to be WNV IgM positive and no yellow fever vaccinees found to be WNV IgM positive. In a selected population of 706 sera, 15 false-positive WNV IgM sera were identified. The use of a background subtraction method for the IgM ELISA eliminated all 15 false-positive results, giving a specificity of 100% for the Focus IgM ELISA.
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