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Viruses, Volume 5, Issue 10 (October 2013) – 18 articles , Pages 2329-2623

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177 KiB  
Article
Evolution of Specific Antibodies and Proviral DNA in Milk of Small Ruminants Infected by Small Ruminant Lentivirus
by Nuria Barquero, Esperanza Gomez-Lucia, Alvaro Arjona, Cristina Toural, Alfonso Las Heras, José F. Fernández-Garayzabal and Ana Domenech
Viruses 2013, 5(10), 2614-2623; https://doi.org/10.3390/v5102614 - 22 Oct 2013
Cited by 21 | Viewed by 6369
Abstract
The diagnosis of Small Ruminant Lentivirus (SRLV) is based on clinical signs, pathological lesions and laboratory testing. No standard reference test for the diagnosis of maedi visna has been validated up to the present, and it is puzzling that tests which detect antibodies [...] Read more.
The diagnosis of Small Ruminant Lentivirus (SRLV) is based on clinical signs, pathological lesions and laboratory testing. No standard reference test for the diagnosis of maedi visna has been validated up to the present, and it is puzzling that tests which detect antibodies against the virus and tests which detect the proviral genome may render opposite results. The aim of this study was to evaluate the presence in milk throughout a lactation period of specific antibodies by ELISA and of SRLV proviral DNA by a PCR of the highly conserved pol region. A six-month study was conducted with the milk of 28 ewes and 31 goats intensively reared. The percentage of animals with antibodies against SRLV increased throughout the study period. Seroprevalence in sheep was 28% at the beginning of the study and by the end it had increased up to 52.4%. In goats, initial seroprevalence of 5.6% increased to 16%. The percentage of PCR positive ewes was stable throughout the study period. Of the positive sheep, 21.4% were PCR-positive before antibodies could be detected and most of them became PCR-negative shortly after the first detection of antibodies. This might suggest that antibodies have a neutralizing effect. In addition, an equal percentage of sheep were always PCR-negative but either became ELISA-positive or was always ELISA-positive, which might support this hypothesis. On the other hand, the PCR results in goats did not follow any pattern and oscillated between 35.3% and 55.6% depending on the month. Most goats positive by PCR failed to develop antibodies in the 6 months tested. We may conclude that the infection and the antibody response to it follow a different trend in sheep and goats. Full article
(This article belongs to the Special Issue Small Ruminant Lentiviruses)
659 KiB  
Article
Detection and Molecular Diversity of Spike Gene of Porcine Epidemic Diarrhea Virus in China
by Jianfei Chen, Xiaozhen Liu, Da Shi, Hongyan Shi, Xin Zhang, Changlong Li, Yanbin Chi and Li Feng
Viruses 2013, 5(10), 2601-2613; https://doi.org/10.3390/v5102601 - 22 Oct 2013
Cited by 80 | Viewed by 8154
Abstract
Since late 2010, porcine epidemic diarrhea virus (PEDV) has rapidly disseminated all over the China and caused considerable morbidity and high mortality (up to 100%) in neonatal piglets. 79.66% (141 of 177) pig farms in 29 provinces (excluding Tibet and Hainan, China) and [...] Read more.
Since late 2010, porcine epidemic diarrhea virus (PEDV) has rapidly disseminated all over the China and caused considerable morbidity and high mortality (up to 100%) in neonatal piglets. 79.66% (141 of 177) pig farms in 29 provinces (excluding Tibet and Hainan, China) and 72.27% (417 of 577) samples were positive for PEDV confirmed by reverse transcription-polymerase chain reaction (RT-PCR). The full-length S genes of representative field strains were sequenced. 33 field strains share 93.5%–99.9% homologies with each other at the nucleotide sequence level and 92.3%–99.8% homologies with each other at the amino acids sequence level. Most field strains have nucleotide deletion and insertion regions, and show lower homologies (93.5%–94.2%) with Chinese classical strain CH/S, however higher homologies (97.1%–99.3%) with recent strain CHGD-1. The phylogenetic analysis showed there are classical strains and variants prevailing in pig herd in China. PEDV has a high detection rate in pig herds in China. Sequence analysis indicated the S genes of recent field strains have heterogeneity and the variants are predominant. Full article
(This article belongs to the Special Issue Animal Arteriviruses and Coronaviruses)
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Review
Foamy Virus Vectors for HIV Gene Therapy
by Miles E. Olszko and Grant D. Trobridge
Viruses 2013, 5(10), 2585-2600; https://doi.org/10.3390/v5102585 - 22 Oct 2013
Cited by 15 | Viewed by 7649
Abstract
Highly active antiretroviral therapy (HAART) has vastly improved outcomes for patients infected with HIV, yet it is a lifelong regimen that is expensive and has significant side effects. Retroviral gene therapy is a promising alternative treatment for HIV/AIDS; however, inefficient gene delivery to [...] Read more.
Highly active antiretroviral therapy (HAART) has vastly improved outcomes for patients infected with HIV, yet it is a lifelong regimen that is expensive and has significant side effects. Retroviral gene therapy is a promising alternative treatment for HIV/AIDS; however, inefficient gene delivery to hematopoietic stem cells (HSCs) has so far limited the efficacy of this approach. Foamy virus (FV) vectors are derived from non-pathogenic viruses that are not endemic to the human population. FV vectors have been used to deliver HIV-inhibiting transgenes to human HSCs, and they have several advantages relative to other retroviral vectors. These include an attractive safety profile, broad tropism, a large transgene capacity, and the ability to persist in quiescent cells. In addition, the titers of FV vectors are not reduced by anti-HIV transgenes that affect the production of lentivirus (LV) vectors. Thus FV vectors are very promising for anti-HIV gene therapy. This review covers the advantages of FV vectors and describes their preclinical development for anti-HIV gene therapy. Full article
(This article belongs to the Special Issue Gene Therapy for Retroviral Infections)
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Review
CD8 and CD4 T Cells in West Nile Virus Immunity and Pathogenesis
by Jason Netland and Michael J. Bevan
Viruses 2013, 5(10), 2573-2584; https://doi.org/10.3390/v5102573 - 22 Oct 2013
Cited by 36 | Viewed by 6415
Abstract
CD4 and CD8 T lymphocytes are adaptive immune cells that play a key role in the immune response to pathogens. They have been extensively studied in a variety of model systems and the mechanisms by which they function are well described. However, the [...] Read more.
CD4 and CD8 T lymphocytes are adaptive immune cells that play a key role in the immune response to pathogens. They have been extensively studied in a variety of model systems and the mechanisms by which they function are well described. However, the responses by these cell types vary widely from pathogen to pathogen. In this review, we will discuss the role of CD8 and CD4 T cells in the immune response to West Nile virus infection. Full article
(This article belongs to the Special Issue West Nile Virus)
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Article
Inhibition of Histone Deacetylation and DNA Methylation Improves Gene Expression Mediated by the Adeno-Associated Virus/Phage in Cancer Cells
by Azadeh Kia, Teerapong Yata, Nabil Hajji and Amin Hajitou
Viruses 2013, 5(10), 2561-2572; https://doi.org/10.3390/v5102561 - 22 Oct 2013
Cited by 20 | Viewed by 6727
Abstract
Bacteriophage (phage), viruses that infect bacteria only, have become promising vectors for targeted systemic delivery of genes to cancer, although, with poor efficiency. We previously designed an improved phage vector by incorporating cis genetic elements of adeno-associated virus (AAV). This novel AAV/phage hybrid [...] Read more.
Bacteriophage (phage), viruses that infect bacteria only, have become promising vectors for targeted systemic delivery of genes to cancer, although, with poor efficiency. We previously designed an improved phage vector by incorporating cis genetic elements of adeno-associated virus (AAV). This novel AAV/phage hybrid (AAVP) specifically targeted systemic delivery of therapeutic genes into tumors. To advance the AAVP vector, we recently introduced the stress-inducible Grp78 tumor specific promoter and found that this dual tumor-targeted AAVP provides persistent gene expression, over time, in cancer cells compared to silenced gene expression from the CMV promoter in the parental AAVP. Herein, we investigated the effect of histone deacetylation and DNA methylation on AAVP-mediated gene expression in cancer cells and explored the effect of cell confluence state on AAVP gene expression efficacy. Using a combination of AAVP expressing the GFP reporter gene, flow cytometry, inhibitors of histone deacetylation, and DNA methylation, we have demonstrated that histone deacetylation and DNA methylation are associated with silencing of gene expression from the CMV promoter in the parental AAVP. Importantly, inhibitors of histone deacetylases boost gene expression in cancer cells from the Grp78 promoter in the dual tumor-targeted AAVP. However, cell confluence had no effect on AAVP-guided gene expression. Our findings prove that combination of histone deacetylase inhibitor drugs with the Grp78 promoter is an effective approach to improve AAVP-mediated gene expression in cancer cells and should be considered for AAVP-based clinical cancer gene therapy. Full article
(This article belongs to the Section Bacterial Viruses)
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Article
Identification and Characterization of Porcine Kobuvirus Variant Isolated from Suckling Piglet in Gansu Province, China
by Shengtao Fan, Heting Sun, Ying Ying, Xiaolong Gao, Zheng Wang, Yicong Yu, Yuanguo Li, Tiecheng Wang, Zhijun Yu, Songtao Yang, Yongkun Zhao, Chuan Qin, Yuwei Gao and Xianzhu Xia
Viruses 2013, 5(10), 2548-2560; https://doi.org/10.3390/v5102548 - 18 Oct 2013
Cited by 18 | Viewed by 6238
Abstract
Kobuviruses comprise three species, the Aichivirus A, Aichivirus B, and Aichivirus C (porcine kobuvirus). Porcine kobuvirus is endemic to pig farms and is not restricted geographically but, rather, is distributed worldwide. The complete genomic sequences of four porcine kobuvirus strains isolated during a [...] Read more.
Kobuviruses comprise three species, the Aichivirus A, Aichivirus B, and Aichivirus C (porcine kobuvirus). Porcine kobuvirus is endemic to pig farms and is not restricted geographically but, rather, is distributed worldwide. The complete genomic sequences of four porcine kobuvirus strains isolated during a diarrhea outbreak in piglets in the Gansu province of China were determined. Two of these strains exhibited variations relative to the traditional strains. The potential 3C/3D cleavage sites of the variant strains were Q/C, which differed from the Q/S in the traditional porcine kobuvirus genome. A 90-nucleotide deletion in the 2B protein and a single nucleotide insertion in the 3′UTR were found in the variant strains. The VP1 regions of all four porcine kobuviruses in our study were highly variable (81%–86%). Ten common amino acid mutations were found specifically at certain positions within the VP1 region. Significant recombination sites were identified using SimPlot scans of whole genome sequences. Porcine kobuviruses were also detected in pig serum, indicating that the virus can escape the gastrointestinal tract and travel to the circulatory system. These findings suggest that mutations and recombination events may have contributed to the high level of genetic diversity of porcine kobuviruses and serve as a driving force in its evolution. Full article
(This article belongs to the Section Animal Viruses)
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204 KiB  
Letter
hMPV Lineage Nomenclature and Heparin Binding
by Penelope Adamson, Sutthiwan Thammawat, Gamaliel Muchondo, Tania Sadlon, John Williams and David Gordon
Viruses 2013, 5(10), 2546-2547; https://doi.org/10.3390/v5102546 - 16 Oct 2013
Cited by 1 | Viewed by 4685
Abstract
Human metapneumovirus (hMPV), first described in 2001 [1], is responsible for causing serious respiratory illness in young children, the elderly and immunocompromised patients. Four distinct lineages of hMPV have been identified with the original nomenclature for these subgroups (A1, A2, B1 and B2), [...] Read more.
Human metapneumovirus (hMPV), first described in 2001 [1], is responsible for causing serious respiratory illness in young children, the elderly and immunocompromised patients. Four distinct lineages of hMPV have been identified with the original nomenclature for these subgroups (A1, A2, B1 and B2), reported by van den Hoogen et al. [2], utilised by many. An alternate terminology (1A, 1B, 2A and 2B) was also published by Ishiguro et al. in 2004 [3] which has been adopted by others. However, this has caused some confusion in the interpretation of publication results as the terminology is similar yet describes different subtypes. As a result, a number of investigators have made a submission to the International Committee on Taxonomy of Viruses (ICTV, ICTV taxonomic proposal 2012.012V) for the official adoption of the original terminology as an approved nomenclature for hMPV [4]. We welcome this officially approved nomenclature which should provide clarification of these subtypes in future. Therefore to assist with the interpretation of our recently published research in the 2012 special issue of Viruses: Pneumoviruses and Metapneumoviruses entitled “Diversity in Glycosaminoglycan Binding Amongst hMPV G Protein Lineages” [5] we have updated the Figure 3 in this letter (see Figure 1), showing the proposed ICTV terminology compared to the Ishiguro classification (used in our publication). Note that in the original publication the alphanumeric order for the Ishiguro classification was transposed (e.g., 1A was referred to as A1). Full article
(This article belongs to the Section Animal Viruses)
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243 KiB  
Review
Oligopeptide M13 Phage Display in Pathogen Research
by Jonas Kügler, Jonas Zantow, Torsten Meyer and Michael Hust
Viruses 2013, 5(10), 2531-2545; https://doi.org/10.3390/v5102531 - 16 Oct 2013
Cited by 33 | Viewed by 20277
Abstract
Phage display has become an established, widely used method for selection of peptides, antibodies or alternative scaffolds. The use of phage display for the selection of antigens from genomic or cDNA libraries of pathogens which is an alternative to the classical way of [...] Read more.
Phage display has become an established, widely used method for selection of peptides, antibodies or alternative scaffolds. The use of phage display for the selection of antigens from genomic or cDNA libraries of pathogens which is an alternative to the classical way of identifying immunogenic proteins is not well-known. In recent years several new applications for oligopeptide phage display in disease related fields have been developed which has led to the identification of various new antigens. These novel identified immunogenic proteins provide new insights into host pathogen interactions and can be used for the development of new diagnostic tests and vaccines. In this review we focus on the M13 oligopeptide phage display system for pathogen research but will also give examples for lambda phage display and for applications in other disease related fields. In addition, a detailed technical work flow for the identification of immunogenic oligopeptides using the pHORF system is given. The described identification of immunogenic proteins of pathogens using oligopeptide phage display can be linked to antibody phage display resulting in a vaccine pipeline. Full article
(This article belongs to the Special Issue Phage Display in Virus Research)
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792 KiB  
Article
In planta Protein Interactions of Three Alphacryptoviruses and Three Betacryptoviruses from White Clover, Red Clover and Dill by Bimolecular Fluorescence Complementation Analysis
by Till Lesker and Edgar Maiss
Viruses 2013, 5(10), 2512-2530; https://doi.org/10.3390/v5102512 - 09 Oct 2013
Cited by 6 | Viewed by 6437
Abstract
Plant-infecting viruses of the genera Alpha- and Betacryptovirus within the family Partitiviridae cause no visible effects on their hosts and are only transmitted by cell division and through gametes. The bipartite dsRNA genome is encoding a RNA-dependent RNA polymerase (RdRp) and a coat [...] Read more.
Plant-infecting viruses of the genera Alpha- and Betacryptovirus within the family Partitiviridae cause no visible effects on their hosts and are only transmitted by cell division and through gametes. The bipartite dsRNA genome is encoding a RNA-dependent RNA polymerase (RdRp) and a coat protein (CP). Aside from sequence and structural analysis, the investigation of protein interactions is another step towards virus characterization. Therefore, ORFs of two type members White Clover Cryptic Virus 1 and 2 (WCCV-1 and WCCV-2), as well as the related viruses from Red Clover and Dill were introduced into a bimolecular fluorescence complementation assay. We showed CP-CP dimerization for all tested viruses with localization for alphacryptoviruses at the nuclear membrane and for betacryptoviruses close to cell walls within the cytoplasm. For CPs of WCCV-1 and WCCV-2, deletion mutants were created to determine internal interaction sites. Moreover, RdRp self-interaction was found for all viruses, whereas CP-RdRp interactions were only detectable for the alphacryptoviruses. An intra-genus test of CPs was successful in various virus combinations, whereas an inter-genus interaction of WCCV-1CP and WCCV-2CP was absent. This is the first report of in vivo protein interactions of members in the family Partitiviridae, indicating distinct features of the alpha- and betacryptoviruses. Full article
(This article belongs to the Section Viruses of Plants, Fungi and Protozoa)
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878 KiB  
Review
Viral and Cellular Requirements for the Nuclear Entry of Retroviral Preintegration Nucleoprotein Complexes
by Kenneth A. Matreyek and Alan Engelman
Viruses 2013, 5(10), 2483-2511; https://doi.org/10.3390/v5102483 - 07 Oct 2013
Cited by 100 | Viewed by 13012
Abstract
Retroviruses integrate their reverse transcribed genomes into host cell chromosomes as an obligate step in virus replication. The nuclear envelope separates the chromosomes from the cell cytoplasm during interphase, and different retroviral groups deal with this physical barrier in different ways. Gammaretroviruses are [...] Read more.
Retroviruses integrate their reverse transcribed genomes into host cell chromosomes as an obligate step in virus replication. The nuclear envelope separates the chromosomes from the cell cytoplasm during interphase, and different retroviral groups deal with this physical barrier in different ways. Gammaretroviruses are dependent on the passage of target cells through mitosis, where they are believed to access chromosomes when the nuclear envelope dissolves for cell division. Contrastingly, lentiviruses such as HIV-1 infect non-dividing cells, and are believed to enter the nucleus by passing through the nuclear pore complex. While numerous virally encoded elements have been proposed to be involved in HIV-1 nuclear import, recent evidence has highlighted the importance of HIV-1 capsid. Furthermore, capsid was found to be responsible for the viral requirement of various nuclear transport proteins, including transportin 3 and nucleoporins NUP153 and NUP358, during infection. In this review, we describe our current understanding of retroviral nuclear import, with emphasis on recent developments on the role of the HIV-1 capsid protein. Full article
(This article belongs to the Special Issue Viral Nuclear Import)
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357 KiB  
Article
West Nile Virus Antibody Prevalence in Horses of Ukraine
by Ute Ziegler, Artem Skrypnyk, Markus Keller, Christoph Staubach, Maksym Bezymennyi, Armando M. Damiani, Nikolaus Osterrieder and Martin H. Groschup
Viruses 2013, 5(10), 2469-2482; https://doi.org/10.3390/v5102469 - 04 Oct 2013
Cited by 12 | Viewed by 6294
Abstract
West Nile virus (WNV) is a mosquito-borne virus of global importance. Over the last two decades, it has been responsible for significant numbers of cases of illness in humans and animals in many parts of the world. In Ukraine, WNV infections in humans [...] Read more.
West Nile virus (WNV) is a mosquito-borne virus of global importance. Over the last two decades, it has been responsible for significant numbers of cases of illness in humans and animals in many parts of the world. In Ukraine, WNV infections in humans and birds were first reported more than 25 years ago, yet the current epidemiological status is quite unclear. In this study, serum samples from over 300 equines were collected and screened in order to detect current WNV activity in Ukraine with the goal to estimate the risk of infection for humans and horses. Sera were tested by enzyme-linked immunosorbent assay (ELISA) and virus neutralization assay (NT) to detect WNV-specific antibodies. The results clearly revealed that WNV circulates in most of the regions from which samples were obtained, shown by a WNV seroprevalence rate of 13.5% of examined horses. This is the first topical report indicating the presence of WNV infections in horses in Ukraine, and the results of this study provide evidence of a widespread WNV circulation in this country. Full article
(This article belongs to the Section Animal Viruses)
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Review
Non-Structural Proteins of Arthropod-Borne Bunyaviruses: Roles and Functions
by Saleh Eifan, Esther Schnettler, Isabelle Dietrich, Alain Kohl and Anne-Lie Blomström
Viruses 2013, 5(10), 2447-2468; https://doi.org/10.3390/v5102447 - 04 Oct 2013
Cited by 49 | Viewed by 14223
Abstract
Viruses within the Bunyaviridae family are tri-segmented, negative-stranded RNA viruses. The family includes several emerging and re-emerging viruses of humans, animals and plants, such as Rift Valley fever virus, Crimean-Congo hemorrhagic fever virus, La Crosse virus, Schmallenberg virus and tomato spotted wilt virus. [...] Read more.
Viruses within the Bunyaviridae family are tri-segmented, negative-stranded RNA viruses. The family includes several emerging and re-emerging viruses of humans, animals and plants, such as Rift Valley fever virus, Crimean-Congo hemorrhagic fever virus, La Crosse virus, Schmallenberg virus and tomato spotted wilt virus. Many bunyaviruses are arthropod-borne, so-called arboviruses. Depending on the genus, bunyaviruses encode, in addition to the RNA-dependent RNA polymerase and the different structural proteins, one or several non-structural proteins. These non-structural proteins are not always essential for virus growth and replication but can play an important role in viral pathogenesis through their interaction with the host innate immune system. In this review, we will summarize current knowledge and understanding of insect-borne bunyavirus non-structural protein function(s) in vertebrate, plant and arthropod. Full article
(This article belongs to the Section Insect Viruses)
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Review
Transport of the Influenza Virus Genome from Nucleus to Nucleus
by Edward C. Hutchinson and Ervin Fodor
Viruses 2013, 5(10), 2424-2446; https://doi.org/10.3390/v5102424 - 02 Oct 2013
Cited by 66 | Viewed by 13365
Abstract
The segmented genome of an influenza virus is encapsidated into ribonucleoprotein complexes (RNPs). Unusually among RNA viruses, influenza viruses replicate in the nucleus of an infected cell, and their RNPs must therefore recruit host factors to ensure transport across a number of cellular [...] Read more.
The segmented genome of an influenza virus is encapsidated into ribonucleoprotein complexes (RNPs). Unusually among RNA viruses, influenza viruses replicate in the nucleus of an infected cell, and their RNPs must therefore recruit host factors to ensure transport across a number of cellular compartments during the course of an infection. Recent studies have shed new light on many of these processes, including the regulation of nuclear export, genome packaging, mechanisms of virion assembly and viral entry and, in particular, the identification of Rab11 on recycling endosomes as a key mediator of RNP transport and genome assembly. This review uses these recent gains in understanding to describe in detail the journey of an influenza A virus RNP from its synthesis in the nucleus through to its entry into the nucleus of a new host cell. Full article
(This article belongs to the Special Issue Viral Nuclear Import)
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Review
Viruses Challenge Selectivity Barrier of Nuclear Pores
by Aksana A. Labokha and Ariberto Fassati
Viruses 2013, 5(10), 2410-2423; https://doi.org/10.3390/v5102410 - 30 Sep 2013
Cited by 16 | Viewed by 6677
Abstract
Exchange between the nucleus and the cytoplasm occurs through nuclear pore complexes (NPCs) embedded in the double membrane of the nuclear envelope. NPC permeability barrier restricts the entry of inert molecules larger than 5 nm in diameter but allows facilitated entry of selected [...] Read more.
Exchange between the nucleus and the cytoplasm occurs through nuclear pore complexes (NPCs) embedded in the double membrane of the nuclear envelope. NPC permeability barrier restricts the entry of inert molecules larger than 5 nm in diameter but allows facilitated entry of selected cargos, whose size can reach up to 39 nm. The translocation of large molecules is facilitated by nuclear transport receptors (NTRs) that have affinity to proteins of NPC permeability barrier. Viruses that enter the nucleus replicate evolved strategies to overcome this barrier. In this review, we will discuss the functional principles of NPC barrier and nuclear transport machinery, as well as the various strategies viruses use to cross the selective barrier of NPCs. Full article
(This article belongs to the Special Issue Viral Nuclear Import)
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Review
Vaccines in Development against West Nile Virus
by Samantha Brandler and Frederic Tangy
Viruses 2013, 5(10), 2384-2409; https://doi.org/10.3390/v5102384 - 30 Sep 2013
Cited by 53 | Viewed by 11303
Abstract
West Nile encephalitis emerged in 1999 in the United States, then rapidly spread through the North American continent causing severe disease in human and horses. Since then, outbreaks appeared in Europe, and in 2012, the United States experienced a new severe outbreak reporting [...] Read more.
West Nile encephalitis emerged in 1999 in the United States, then rapidly spread through the North American continent causing severe disease in human and horses. Since then, outbreaks appeared in Europe, and in 2012, the United States experienced a new severe outbreak reporting a total of 5,387 cases of West Nile virus (WNV) disease in humans, including 243 deaths. So far, no human vaccine is available to control new WNV outbreaks and to avoid worldwide spreading. In this review, we discuss the state-of-the-art of West Nile vaccine development and the potential of a novel safe and effective approach based on recombinant live attenuated measles virus (MV) vaccine. MV vaccine is a live attenuated negative-stranded RNA virus proven as one of the safest, most stable and effective human vaccines. We previously described a vector derived from the Schwarz MV vaccine strain that stably expresses antigens from emerging arboviruses, such as dengue, West Nile or chikungunya viruses, and is strongly immunogenic in animal models, even in the presence of MV pre-existing immunity. A single administration of a recombinant MV vaccine expressing the secreted form of WNV envelope glycoprotein elicited protective immunity in mice and non-human primates as early as two weeks after immunization, indicating its potential as a human vaccine. Full article
(This article belongs to the Section Viral Immunology, Vaccines, and Antivirals)
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Brief Report
Sequence Heterogeneity of the ORF3 Gene of Porcine Epidemic Diarrhea Viruses Field Samples in Fujian, China, 2010–2012
by Xi Chen, Lili Zeng, Jinxian Yang, Fusong Yu, Junqing Ge, Qing Guo, Xindang Gao and Tieying Song
Viruses 2013, 5(10), 2375-2383; https://doi.org/10.3390/v5102375 - 30 Sep 2013
Cited by 23 | Viewed by 6562
Abstract
Twenty-seven field samples that showed positive in PEDV detection were collected from different farms of Fujian province from 2010 to 2012. Their heterogeneity was investigated by analysis of the ORF3 gene because of its potential function as a representation of virulence. According to [...] Read more.
Twenty-seven field samples that showed positive in PEDV detection were collected from different farms of Fujian province from 2010 to 2012. Their heterogeneity was investigated by analysis of the ORF3 gene because of its potential function as a representation of virulence. According to the results, six Fujian strains in Group 1 showed a different genotype with unique point mutations, which might be used in differentiation between PEDV groups and brought potential antigenic variation. P55 and five reference strains in Group 2 had a long length deletion, showing another genotype and might be involved in the variation of virulence. Phylogenetic analysis revealed that the collected Fujian strains were very distant from the vaccine development strain CV777, which might be the reason why the vaccine was inefficient to control the disease. The results can help to reconsider the strategy of PEDV vaccine management and prevent outbreaks of PEDV-induced diarrhea more efficiently. Full article
(This article belongs to the Special Issue Animal Arteriviruses and Coronaviruses)
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Review
Evolution of Foamy Viruses: The Most Ancient of All Retroviruses
by Axel Rethwilm and Jochen Bodem
Viruses 2013, 5(10), 2349-2374; https://doi.org/10.3390/v5102349 - 25 Sep 2013
Cited by 44 | Viewed by 8409
Abstract
Recent evidence indicates that foamy viruses (FVs) are the oldest retroviruses (RVs) that we know and coevolved with their hosts for several hundred million years. This coevolution may have contributed to the non-pathogenicity of FVs, an important factor in development of foamy viral [...] Read more.
Recent evidence indicates that foamy viruses (FVs) are the oldest retroviruses (RVs) that we know and coevolved with their hosts for several hundred million years. This coevolution may have contributed to the non-pathogenicity of FVs, an important factor in development of foamy viral vectors in gene therapy. However, various questions on the molecular evolution of FVs remain still unanswered. The analysis of the spectrum of animal species infected by exogenous FVs or harboring endogenous FV elements in their genome is pivotal. Furthermore, animal studies might reveal important issues, such as the identification of the FV in vivo target cells, which than require a detailed characterization, to resolve the molecular basis of the accuracy with which FVs copy their genome. The issues of the extent of FV viremia and of the nature of the virion genome (RNA vs. DNA) also need to be experimentally addressed. Full article
(This article belongs to the Special Issue Recent Progress in Foamy Virus (FV) Research)
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Review
Diagnosis of West Nile Virus Human Infections: Overview and Proposal of Diagnostic Protocols Considering the Results of External Quality Assessment Studies
by Vittorio Sambri, Maria R. Capobianchi, Francesca Cavrini, Rémi Charrel, Olivier Donoso-Mantke, Camille Escadafal, Leticia Franco, Paolo Gaibani, Ernest A. Gould, Matthias Niedrig, Anna Papa, Anna Pierro, Giada Rossini, Andrea Sanchini, Antonio Tenorio, Stefania Varani, Ana Vázquez, Caterina Vocale and Herve Zeller
Viruses 2013, 5(10), 2329-2348; https://doi.org/10.3390/v5102329 - 25 Sep 2013
Cited by 54 | Viewed by 10015
Abstract
West Nile virus, genus Flavivirus, is transmitted between birds and occasionally other animals by ornithophilic mosquitoes. This virus also infects humans causing asymptomatic infections in about 85% of cases and <1% of clinical cases progress to severe neuroinvasive disease. The virus also [...] Read more.
West Nile virus, genus Flavivirus, is transmitted between birds and occasionally other animals by ornithophilic mosquitoes. This virus also infects humans causing asymptomatic infections in about 85% of cases and <1% of clinical cases progress to severe neuroinvasive disease. The virus also presents a threat since most infections remain unapparent. However, the virus contained in blood and organs from asymptomatically infected donors can be transmitted to recipients of these infectious tissues. This paper reviews the presently available methods to achieve the laboratory diagnosis of West Nile virus infections in humans, discussing the most prominent advantages and disadvantages of each in light of the results obtained during four different External Quality Assessment studies carried out by the European Network for ‘Imported’ Viral Diseases (ENIVD). Full article
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