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See detailCloning of the koi herpesvirus genome as an infectious bacterial artificial chromosome demonstrates that disruption of the thymidine kinase locus induces partial attenuation in Cyprinus carpio koi.
Costes, Bérénice ULg; Fournier, Guillaume ULg; Michel, Benjamin ULg et al

in Journal of Virology (2008), 82(10), 4955-4964

Koi herpesvirus (KHV) is the causative agent of a lethal disease in koi and common carp. In the present study, we describe the cloning of the KHV genome as a stable and infectious bacterial artificial ... [more ▼]

Koi herpesvirus (KHV) is the causative agent of a lethal disease in koi and common carp. In the present study, we describe the cloning of the KHV genome as a stable and infectious bacterial artificial chromosome (BAC) clone that can be used to produce KHV recombinant strains. This goal was achieved by the insertion of a loxP-flanked BAC cassette into the thymidine kinase (TK) locus. This insertion led to a BAC plasmid that was stably maintained in bacteria and was able to regenerate virions when permissive cells were transfected with the plasmid. Reconstituted virions free of the BAC cassette but carrying a disrupted TK locus (the FL BAC-excised strain) were produced by the transfection of Cre recombinase-expressing cells with the BAC. Similarly, virions with a wild-type revertant TK sequence (the FL BAC revertant strain) were produced by the cotransfection of cells with the BAC and a DNA fragment encoding the wild-type TK sequence. Reconstituted recombinant viruses were compared to the wild-type parental virus in vitro and in vivo. The FL BAC revertant strain and the FL BAC-excised strain replicated comparably to the parental FL strain. The FL BAC revertant strain induced KHV infection in koi carp that was indistinguishable from that induced by the parental strain, while the FL BAC-excised strain exhibited a partially attenuated phenotype. Finally, the usefulness of the KHV BAC for recombination studies was demonstrated by the production of an ORF16-deleted strain by using prokaryotic recombination technology. The availability of the KHV BAC is an important advance that will allow the study of viral genes involved in KHV pathogenesis, as well as the production of attenuated recombinant candidate vaccines. [less ▲]

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See detailBovine herpesvirus 1 infection and infectious bovine rhinotracheitis
Muylkens, Benoît ULg; Thiry, Julien ULg; Kirten, P. et al

in Veterinary Research (2007), 38(2), 181-209

Bovine herpesvirus 1 (BoHV-1), classified as an alphaherpesvirus, is a major pathogen of cattle. Primary infection is accompanied by various clinical manifestations such as infectious bovine ... [more ▼]

Bovine herpesvirus 1 (BoHV-1), classified as an alphaherpesvirus, is a major pathogen of cattle. Primary infection is accompanied by various clinical manifestations such as infectious bovine rhinotracheitis, abortion, infectious pustular vulvovaginitis, and systemic infection in neonates. When animals survive, a life-long latent infection is established in nervous sensory ganglia. Several reactivation stimuli can lead to viral re-excretion, which is responsible for the maintenance of BoHV-1 within a cattle herd. This paper focuses on an updated pathogenesis based on a molecular characterization of BoHV-1 and the description of the virus cycle. Special emphasis is accorded to the impact of the latency and reactivation cycle on the epidemiology and the control of BoHV-1. Several European countries have initiated BoHV-1 eradication schemes because of the significant losses incurred by disease and trading restrictions. The vaccines used against BoHV-1 are described in this context where the differentiation of infected from vaccinated animals is of critical importance to achieve BoHV-1 eradication. [less ▲]

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See detailIntraspecific bovine herpesvirus 1 recombinants carrying glycoprotein E deletion as a vaccine marker are virulent in cattle
Muylkens, Benoît ULg; Meurens, F.; Schynts, F. et al

in Journal of General Virology (2006), 87(Pt 8), 2149-2154

Vaccines used in control programmes of Bovine herpesvirus 1 (BoHV-1) utilize highly attenuated BoHV-1 strains marked by a deletion of the glycoprotein E (gE) gene. Since BoHV-1 recombinants are obtained ... [more ▼]

Vaccines used in control programmes of Bovine herpesvirus 1 (BoHV-1) utilize highly attenuated BoHV-1 strains marked by a deletion of the glycoprotein E (gE) gene. Since BoHV-1 recombinants are obtained at high frequency in experimentally coinfected cattle, the consequences of recombination on the virulence of gE-negative BoHV-1 were investigated. Thus, gE-negative BoHV-1 recombinants were generated in vitro from several virulent BoHV-1 and one mutant BoHV-1 deleted in the gC and gE genes. Four gE-negative recombinants were tested in the natural host. All the recombinants were more virulent than the gE-negative BoHV-1 vaccine and the gC- and gE-negative parental BoHV-1. The gE-negative recombinant isolated from a BoHV-1 field strain induced the highest severe clinical score. Latency and reactivation studies showed that three of the recombinants were reexcreted. Recombination can therefore restore virulence of gE-negative BoHV-1 by introducing the gE deletion into a different virulence background. [less ▲]

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See detailRecombination in the alphaherpesvirus bovine herpesvirus 1
Thiry, Etienne ULg; Muylkens, Benoît ULg; Meurens, F. et al

in Veterinary Microbiology (2006), 113(3-4), 171-177

Herpesviruses are DNA viruses characterized by a low rate of nucleotide substitution. Therefore. other mechanisms must be involved to their evolution, like recombination that can be seen as an essential ... [more ▼]

Herpesviruses are DNA viruses characterized by a low rate of nucleotide substitution. Therefore. other mechanisms must be involved to their evolution, like recombination that can be seen as an essential evolutionary driving force of these viruses. Recombination contributes to the long-term evolution of alphaherpes viruses. It acts also to continuously create new alphaherpesvirus strains. We have used bovine herpesvirus 1 to investigate recombination both within DNA concatemers in infected cells and in vitro and in vivo at the end of the lytic cycle. The following results have been obtained: (i) intramolecular recombination occurs at the level of concatemers and gives rise to genomic segment inversions: (ii) intraspecific recombination occurs frequently both in vitro and in vivo; (iii) interspecific recombination is possible and requires two highly genetically related viruses (iv) only simultaneous or closely separated infections lead to the production of recombinant viruses: (v) recombination between wild-type and glycoprotein defective vaccine virus can produce a glycoprotein defective virus keeping part of the virulence of parental wild-type virus. Recombination, by exchanging genomic segments, may modify the virulence of alphaherpesviruses. It must be carefully assessed for the biosafety of antiviral therapy, alphaherpesvirus-based vectors and live attenuated vaccines. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

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See detailBiological characterization of bovine herpesvirus 1 recombinants possessing the vaccine glycoprotein E negative phenotype
Muylkens, Benoît ULg; Meurens, F.; Schynts, F. et al

in Veterinary Microbiology (2006), 113(3-4), 283-291

Intramolecular recombination is a frequent event during the replication cycle of bovine herpesvirus 1 (BoHV-1). Recombinant viruses frequently arise and survive in cattle after concomitant nasal ... [more ▼]

Intramolecular recombination is a frequent event during the replication cycle of bovine herpesvirus 1 (BoHV-1). Recombinant viruses frequently arise and survive in cattle after concomitant nasal infections with two BoHV-1 mutants. The consequences of this process, related to herpesvirus evolution, have to be assessed in the context of large use of live marker vaccines based on glycoprotein E (gE) gene deletion. In natural conditions, double nasal infections by vaccine and wild-type strains are likely to occur. This situation might generate virulent recombinant viruses inducing a serological response indistinguishable from the vaccine one. This question was addressed by generating in vitro BoHV-1 recombinants deleted in the gE gene from seven wild-type BoHV-1 strains and one mutant strain deleted in the genes encoding gC and gE. In vitro growth properties were assessed by virus production, one step growth kinetics and plaque size assay. Heterogeneity in the biological properties was shown among the investigated recombinant viruses. The results demonstrated that some recombinants. in spite of their gE minus phenotype, have biological characteristics close to wild-type BoHV-1. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

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See detailCharacterization of caprine herpesvirus 1 glycoprotein D gene and its translation product
Keuser, Véronique; Detry, Bruno; Thiry, Julien ULg et al

in Virus Research (2006), 115(2), 112-121

Caprine herpesvirus 1 (CpHV- 1) is responsible of systemic infection in neonatal kids as well as abortion and fertility disorders in adult goats. This virus is closely related to bovine herpesvirus 1 ... [more ▼]

Caprine herpesvirus 1 (CpHV- 1) is responsible of systemic infection in neonatal kids as well as abortion and fertility disorders in adult goats. This virus is closely related to bovine herpesvirus 1 (BoHV-1) which causes infectious bovine rhinotracheitis. Glycoprotein D (gD) mediates important functions in alphaherpesviruses and is also a main inummogen. The sequence of CpHV-1 gD gene and the biochemical properties of its translation product were analyzed and compared to those of BoHV-1 and other alphaherpesviruses. A relatively high homology was found between CpHV-1 and BoHV-1 glycoproteins D amino acid sequences (similarity of 68.8%). Moreover, six cysteine residues are conserved by CpHV-1 gD and the other studied alphaherpesviruses. CpHV-1 gD has a molecular mass similar to BoHV-1 gD and contains complex N-linked oligosaccharides. In contrast to the BoHV-1 gD, CpHV-1 gD is expressed as a late protein. In spite of the observed differences which could influence its biological functions, CpHV-1 gD, shares most characteristics with other alphaherpesviruses and especially BoHV-1. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

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See detailRecombination in alphaherpesviruses
Thiry, Etienne ULg; Meurens, F.; Muylkens, Benoît ULg et al

in Reviews in Medical Virology (2005), 15(2, Mar-Apr), 89-103

Within the Herpesviridae family, Alphaherpesvirinae is an extensive subfamily which contains numerous mammalian and avian viruses. Given the low rate of herpesvirus nucleotide substitution, recombination ... [more ▼]

Within the Herpesviridae family, Alphaherpesvirinae is an extensive subfamily which contains numerous mammalian and avian viruses. Given the low rate of herpesvirus nucleotide substitution, recombination can be seen as an essential evolutionary driving force although it is likely underestimated. Recombination in alphaherpesviruses is intimately linked to DNA replication. Both viral and cellular proteins participate in this recombination-dependent replication. The presence of inverted repeats in the alphaherpesvirus genomes allows segment inversion as a consequence of specific recombination between repeated sequences during DNA replication. High molecular weight intermediates of replication, called concatemers, are the site of early recombination events. The analysis of concatemers, from cells coinfected by two distinguishable alphaherpesviruses provides an efficient tool to study recombination without the bias introduced by invisible or non-viable recombinants, and by dominance of a virus over recombinants. Intraspecific recombination frequently occurs between strains of the same alphaherpesvirus species. Interspecific recombination depends on enough sequence similarity to enable recombination between distinct alphaherpesvirus species. The most important prerequisite for successful recombination is coinfection of the individual host by different virus strains or species. Consequently the following factors affecting the distribution of different viruses to shared target cells need to be considered: dose of inoculated virus, time interval between inoculation of the first and the second virus, distance between the marker mutations, genetic homology, virulence and latency. Recombination, by exchanging genomic segments, may modify the virulence of alphaherpesviruses. It must be carefully assessed for the biosafety of antiviral therapy, alphaherpesvirus-based vectors and live attenuated vaccines. Copyright (C) 2004 John Wiley Sons, Ltd. [less ▲]

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See detailInterspecific recombination between two ruminant alphaherpesviruses, bovine herpesviruses 1 and 5
Meurens, F.; Keil, G. M.; Muylkens, Benoît ULg et al

in Journal of Virology (2004), 78(18), 9828-9836

Homologous recombination between different species of alphaherpesviruses has been described between herpes simplex viruses 1 and 2 but has not yet been observed between other alphaherpesviruses. In the ... [more ▼]

Homologous recombination between different species of alphaherpesviruses has been described between herpes simplex viruses 1 and 2 but has not yet been observed between other alphaherpesviruses. In the present study we chose to assess to what extent in vitro recombination can occur between members of a well-defined group of closely related viruses such as ruminant alphaherpesviruses. At 24 h after infection of epithelial bovine kidney cells with a double-deleted mutant of bovine herpesvirus 1 (BoHV-1) (containing green fluorescent protein and red fluorescent protein genes) and different ruminant alphaherpesviruses, four types of progeny viruses were detected and distinguished according to their phenotype. Frequent recombination events between identical or different strains of BoHV-1 were observed (up to 30%), whereas only two BoHV-1/BoHV-5 recombinants were identified, and no recombinants between BoHV-1 and less closely related caprine and cervine herpesviruses were detected. Restriction analysis of the genomes of the two BoHV-1/BoHV-5 recombinants showed different genetic backgrounds. One possessed a restriction pattern close to BoHV-1, whereas the other one was close to BoHV-5. This exhaustive analysis of each combination of coinfection in a unique situation of five closely related alphaherpesviruses revealed the importance of a high degree of genetic relatedness and similar parental virus growth kinetics for successful interspecific recombination. [less ▲]

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See detailSuperinfection prevents recombination of the alphaherpesvirus bovine herpesvirus 1
Meurens, F.; Schynts, F.; Keil, G. M. et al

in Journal of Virology (2004), 78(8), 3872-3879

Homologous recombination between strains of the same alphaherpesvirus species occurs frequently both in vitro and in vivo. This process has been described between strains of herpes simplex virus type 1 ... [more ▼]

Homologous recombination between strains of the same alphaherpesvirus species occurs frequently both in vitro and in vivo. This process has been described between strains of herpes simplex virus type 1, herpes simplex virus type 2, pseudorabies virus, feline herpesvirus 1, varicella-zoster virus, and bovine herpesvirus 1 (BoHV-1). In vivo, the rise of recombinant viruses can be modulated by different factors, such as the dose of the inoculated viruses, the distance between inoculation sites, the time interval between inoculation of the first and the second virus, and the genes in which the mutations are located. The effect of the time interval between infections with two distinguishable BoHV-1 on recombination was studied in three ways: (i) recombination at the level of progeny viruses, (ii) interference induced by the first virus infection on beta-gallactosidase gene expression of a superinfecting virus, and (iii) recombination at the level of concatemeric DNA. A time interval of 2 to 8 h between two successive infections allows the establishment of a barrier, which reduces or prevents any successful superinfection needed to generate recombinant viruses. The dramatic effect of the time interval on the rise of recombinant viruses is particularly important for the risk assessment of recombination between glycoprotein E-negative marker vaccine and field strains that could threaten BoHV-1 control and eradication programs. [less ▲]

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See detailIsolation of caprine herpesvirus type 1 in Spain
Keuser, V.; Espejo-Serrano, J.; Schynts, F. et al

in Veterinary Record : Journal of the British Veterinary Association (2004), 154(13), 395-399

Two strains of caprine herpesvirus type 1 (CpHV-1) were isolated after the experimental reactivation of two seropositive goats in Spain. Viral DNA from these isolates was compared with DNA from bovine ... [more ▼]

Two strains of caprine herpesvirus type 1 (CpHV-1) were isolated after the experimental reactivation of two seropositive goats in Spain. Viral DNA from these isolates was compared with DNA from bovine herpesvirus type 1 and CpHV-1 reference strains by restriction endonuclease analysis. The two Spanish isolates were closely related but could easily be distinguished from each other and from the reference strains. [less ▲]

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See detailImproved antigenic methods for differential diagnosis of bovine, caprine, and cervine alphaherpesviruses related to bovine herpesvirus 1
Keuser, V.; Schynts, F.; Detry, Bruno et al

in Journal of Clinical Microbiology (2004), 42(3), 1228-1235

The control of infectious bovine rhinotracheitis induced by bovine herpesvirus 1 (BoHV-1) requires sensitive and specific diagnostic assays. As BoHV-1 is antigenically and genetically related to four ... [more ▼]

The control of infectious bovine rhinotracheitis induced by bovine herpesvirus 1 (BoHV-1) requires sensitive and specific diagnostic assays. As BoHV-1 is antigenically and genetically related to four other alphaherpesviruses of ruminants-namely, BoHV-5, caprine herpesvirus 1 (CpHV-1), cervine herpesvirus 1 (CvHV-1) and CvHV-2-diagnostic tests able to discriminate BoHV-1 from these related viruses are needed to avoid misdiagnosis, especially because some of these viruses are able to cross the species barrier. In this study, murine monoclonal antibodies (MAbs) specific for BoHV-1, BoHV-5, CpHV-1, CvHV-1, and CvHV-2 were produced with the aim of setting up an immunofluorescence assay able to discriminate between these related herpesviruses. Produced MAbs were selected for their viral specificity by enzyme-linked immunosorbent assay and indirect immunofluorescence staining of virus-infected cells. Radioimmunoprecipitation characterization of the selected MAbs revealed that four of them are directed against glycoprotein C (gC) and one of them is directed against gD of these related viruses. The obtained results demonstrate that the antibodies produced allow an unambiguous discrimination of each of the four alphaherpesviruses related to BoHV-1. [less ▲]

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See detailBovine herpesvirus 1 glycoprotein D expression in bovine upper respiratory tract mediated by a human adenovirus type 5
Gogev, S.; Georgin, J. P.; Schynts, F. et al

in Veterinary Research (2004), 35(6, Nov-Dec), 715-721

Bovine herpesvirus 1 glycoprotein D (gD) gene expression by recombinant replication defective human adenovirus type 5 (HAdV-5) was investigated in calves using indirect immunofluorescence microscopy (IIFM ... [more ▼]

Bovine herpesvirus 1 glycoprotein D (gD) gene expression by recombinant replication defective human adenovirus type 5 (HAdV-5) was investigated in calves using indirect immunofluorescence microscopy (IIFM), confocal laser scanning microscopy (CLSM) and RT-PCR. One fold intranasal instillation of HAdV-5-expressing gD in the cattle upper respiratory tract showed a short term expression of at least 5 days, but not 10 days, limited only to epithelial cells localised in the epithelium of the nasal mucosa in one out of six calves. Observed limited gene transfer into well differentiated cattle airway epithelial cells must be taken into consideration in order to enhance transfection efficiency, and consequently the vaccine potential of this vector. [less ▲]

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See detailInvestigation of the susceptibility of human cell lines to bovine herpesvirus 4 infection: Demonstration that human cells can support a nonpermissive persistent infection which protects them against tumor necrosis factor alpha-induced apoptosis
Gillet, Laurent ULg; Minner, F.; Detry, Bruno et al

in Journal of Virology (2004), 78(5), 2336-2347

Bovine herpesvirus 4 (BoHV-4) is a gammaherpesvirus that has a worldwide distribution in the population of cattle. Many factors make human contamination by BoHV-4 likely to occur. In this study, we ... [more ▼]

Bovine herpesvirus 4 (BoHV-4) is a gammaherpesvirus that has a worldwide distribution in the population of cattle. Many factors make human contamination by BoHV-4 likely to occur. In this study, we performed in vitro experiments to assess the risk and the consequences of human infection by BoHV-4. First, by using a recombinant BoHV-4 strain expressing enhanced green fluorescent protein under the control of the human cytomegalovirus immediate-early gene promoter, we tested 21 human cell lines for their sensitivity and their permissiveness to BoHV-4 infection. These experiments revealed that human cell lines from lymphoid and myeloid origins were resistant to infection, whereas epithelial cells, carcinoma cells, or adenocarcinoma cells isolated from various organs were sensitive but poorly permissive to BoHV-4 infection. Second, by using the HeLa cell line as a model of human cells sensitive but not permissive to BoHV-4 infection, we investigated the resistance of infected cells to apoptosis and the persistence of the infection through cellular divisions. The results obtained can be summarized as follows. (i) BoHV-4 nonpermissive infection of HeLa cells protects them against tumor necrosis factor alpha-induced apoptosis. (ii) BoHV-4 infection of HeLa cells persists in cell culture; however, the percentage of infected cells decreases with time due to erratic transmission of the viral genome through cell division. (iii) BoHV-4 infection has no effect on the rate of HeLa cell division. Altogether, these data suggest that BoHV-4 could infect humans. This study also stresses the importance of considering the insidious effects of nonpermissive infection when the biosafety of animal gammaherpesviruses for humans is being considered. [less ▲]

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See detailRise and survival of bovine herpesvirus 1 recombinants after primary infection and reactivation from latency
Schynts, F.; Meurens, F.; Detry, Bruno et al

in Journal of Virology (2003), 77(23), 12535-12542

Recombination is thought to be an important source of genetic variation in herpesviruses. Several studies, performed in vitro or in vivo, detected recombinant viruses after the coinoculation of two ... [more ▼]

Recombination is thought to be an important source of genetic variation in herpesviruses. Several studies, performed in vitro or in vivo, detected recombinant viruses after the coinoculation of two distinguishable strains of the same herpesvirus species. However, none of these studies investigated the evolution of the relative proportions of parental versus recombinant progeny populations after coinoculation of the natural host, both during the excretion and the reexcretion period. In the present study, we address this by studying the infection of cattle with bovine herpesvirus 1 (BoHV-1). The recombination of two BoHV-1 mutants lacking either glycoprotein C (gC(-)/gE(+)) or E (gC(+)/gE(-)) was investigated after inoculation of cattle by the natural route of infection. The results demonstrated that (i) recombination is a frequent event in vivo since recombinants (gC(+)/gE(+) and gC(-)/gE(-)) were detected in all coinoculated calves, (ii) relative proportions of progeny populations evolved during the excretion period toward a situation where two populations (gC(+)/gE(+) and gC(-)/gE(+)) predominated without fully outcompeting the presence of the two other detected populations (gC(+)/gE(-) and gC(-)/gE(-)), and (iii) after reactivation from latency, no gC(+)/gE(-) and gC(-)/gE(-) progeny viruses were detected, although gC(+)/gE(-) mutants, when inoculated alone, were detected after reactivation treatment. In view of these data, the importance of gE in the biology of BoHV-1 infection and the role of recombination in herpesvirus evolution are discussed. [less ▲]

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See detailBiosafety of Herpesvirus Vectors
Gogev, S.; Schynts, F.; Meurens, F. et al

in Current Gene Therapy (2003), 3(6), 597-611

Herpesviruses are large DNA viruses, which possess a number of advantages as gene delivery vectors. These relate to an ability to package large DNA insertions and establish lifelong latent infections in ... [more ▼]

Herpesviruses are large DNA viruses, which possess a number of advantages as gene delivery vectors. These relate to an ability to package large DNA insertions and establish lifelong latent infections in which the viral genome exists as a stable episome in the nucleus. For gene therapy to become a potential future treatment option, biosafe therapeutically efficient gene transfer is a central, but more and more stringent requirement. This review highlights the progress in development of herpesvirus based vectors, describes their properties as wall as discusses the biosafety concerns that are associated with their use in gene therapy. Thought was also given to biosafety issues pertaining to design and production of herpesvirus vector systems in therapeutic gene delivery. [less ▲]

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See detailThe structures of bovine herpesvirus 1 virion and concatemeric DNA: implications for cleavage and packaging of herpesvirus genomes
Schynts, F.; McVoy, M. A.; Meurens, F. et al

in Virology (2003), 314(1), 326-335

Herpesvirus genomes are often characterized by the presence of direct and inverted repeats that delineate their grouping into six structural classes. Class D genomes consist of a long (L) segment and a ... [more ▼]

Herpesvirus genomes are often characterized by the presence of direct and inverted repeats that delineate their grouping into six structural classes. Class D genomes consist of a long (L) segment and a short (S) segment. The latter is flanked by large inverted repeats. DNA replication produces concatemers of head-to-tail linked genomes that are cleaved into unit genomes during the process of packaging DNA into capsids. Packaged class D genomes are an equimolar mixture of two isomers in which S is in either of two orientations, presumably a consequence of homologous recombination between the inverted repeats. The L segment remains predominantly fixed in a prototype (P) orientation; however, low levels of genomes having inverted L (I-L) segments have been reported for some class D herpesviruses. Inefficient formation of class D I-L genomes has been attributed to infrequent L segment inversion, but recent detection of frequent inverted L segments in equine herpesvirus 1 concatemers [Virology 229 (1997) 415-420] suggests that the defect may be at the level of cleavage and packaging rather than inversion. In this study, the structures of virion and concatemeric DNA of another class D herpesvirus, bovine herpesvirus 1, were determined. Virion DNA contained low levels of I-L genomes, whereas concatemeric DNA contained significant amounts of L segments in both P and I-L orientations. However, concatemeric termini exhibited a preponderance of L termini derived from P isomers which was comparable to the preponderance of P genomes found in virion DNA. Thus, the defect in formation of I-L genomes appears to lie at the level of concatemer cleavage. These results have important implications for the mechanisms by which herpesvirus DNA cleavage and packaging occur. (C) 2003 Elsevier Inc. All rights reserved. [less ▲]

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See detailIsolation of a glycoprotein E-deleted bovine herpesvirus type 1 strain in the field
Dispas, M.; Schynts, F.; Lemaire, Mylène et al

in Veterinary Record : Journal of the British Veterinary Association (2003), 153(7), 209-212

During a field trial to evaluate the efficacy of repeated vaccinations with bovine herpesvirus type 1 (BHV-1) marker vaccines, a glycoprotein E (gE)-negative BHV-1 strain was isolated from the nasal ... [more ▼]

During a field trial to evaluate the efficacy of repeated vaccinations with bovine herpesvirus type 1 (BHV-1) marker vaccines, a glycoprotein E (gE)-negative BHV-1 strain was isolated from the nasal secretions of two cows, eight months after vaccination with a gE-negative live-attenuated vaccine, initially given intranasally, then intramuscularly. The strain isolated was characterised using immunofluorescence, restriction analysis and PCR. All the techniques used identified the isolated virus as a gE-negative BHV-1 phenotypically and genotypically identical to the Za strain used as a control. [less ▲]

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See detailDemonstration of generalized infection with caprine herpesvirus 1 diagnosed in an aborted caprine fetus by PCR
Keuser, V.; Gogev, S.; Schynts, F. et al

in Veterinary Research Communications (2002), 26(3), 221-226

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See detailInduction of protective immunity to bovine herpesvirus type 1 in cattle by intranasal administration of replication-defective human adenovirus type 5 expressing glycoprotein gC or gD
Gogev, S.; Vanderheijden, N.; Lemaire, Mylène et al

in Vaccine (2002), 20(9-10), 1451-1465

Replication-defective human adenoviruses type 5 (HAd5) expressing the bovine herpesvirus type 1 (BHV-1) glycoprotein gC or gD under the control of the human cytomegalovirus immediate-early promoter ... [more ▼]

Replication-defective human adenoviruses type 5 (HAd5) expressing the bovine herpesvirus type 1 (BHV-1) glycoprotein gC or gD under the control of the human cytomegalovirus immediate-early promoter/enhancer (AdCMVgC or AdCMVgD) or the 5' regulatory region of the human desmin gene (AdDESMgC or AdDESMgD) were generated. A preliminary experiment performed on rabbits showed that the intranasal administration of AdCMV elicited higher levels of BHV-1 neutralizing antibodies than the intramuscular administration of AdDESM. The obtained results allowed to select the replication-defective AdCMVgC and AdCMVgD for further assessment of their potential as a recombinant vaccine in cattle. Calves were injected intranasally twice 3 weeks apart with either AdCMVgC or AdCMVgD or a combination of these two recombinants or a commercially available live vaccine for comparison. The highest BHV-1 neutralizing antibody titres were obtained with AdCMVgD followed by the live vaccine and to a lower extent with the combination of the two recombinants (AdCMVgC+AdCMVgD). Calves were protected against intranasal BHV-1 challenge performed 3 weeks after the second immunization. In view of the obtained results, recombinant HAd5 may be developed as an intranasal vaccine vector in cattle administrated either alone or sequentially with non-human adenovirus-based vectors. [less ▲]

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See detailCaractéristiques du système immunitaire du fœtus bovin et du veau nouveau-né. Implications dans la prévention et le diagnostic des infections d’origine virale
Thiry, Etienne ULg; Schynts, F.; Lemaire, Mylène

in Annales de Médecine Vétérinaire (2002), 146(4, AUG-SEP), 225-232

In this review the characteristics of the immune system of the bovine fetus and neonate are presented. These characteristics are important for the prevention and diagnosis of viral infections. Three ... [more ▼]

In this review the characteristics of the immune system of the bovine fetus and neonate are presented. These characteristics are important for the prevention and diagnosis of viral infections. Three examples are illustrated in this review : direct and indirect consequences of the infection of the fetus by the bovine viral diarrhea virus; guidelines for a prevention and diagnosis of this viral infection are given; the infection of the neonate by rotaviruses where colostral immunity has a key role in the prevention of the disease; the infection of the neonate by bovine herpesvirus 1 in the presence of colostral immunity which does not prevent latency and can lead to seronegative latent carriers after the disappearance of maternal antibodies. [less ▲]

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