References of "Kerkhofs, P"
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See detailSequence-optimised E2 constructs from BVDV-1b and BVDV-2 for DNA immunisation in cattle
Couvreur, B.; Letellier, C.; Olivier, Fabrice ULg et al

in Veterinary Research (2007), 38(6, NOV-DEC), 819-834

We report DNA immunisation experiments in cattle using plasmid constructs that encoded glycoprotein E2 from bovine viral diarrhoea virus (BVDV)-1 (E2.1) and BVDV-2 (E2.2). The coding sequences were ... [more ▼]

We report DNA immunisation experiments in cattle using plasmid constructs that encoded glycoprotein E2 from bovine viral diarrhoea virus (BVDV)-1 (E2.1) and BVDV-2 (E2.2). The coding sequences were optimised for efficient expression in mammalian cells. A modified leader peptide sequence from protein gD of BoHV1 was inserted upstream of the E2 coding sequences for efficient membrane export of the proteins. Recombinant E2 were efficiently expressed in COS7 cells and they presented the native viral epitopes as judged by differential recognition by antisera from cattle infected with BVDV-1 or BVDV-2. Inoculation of pooled plasmid DNA in young cattle elicited antibodies capable of neutralising viral strains representing the major circulating BVDV genotypes. [less ▲]

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See detailInhibition of bovine sperm-zona binding by bovine herpesvirus-1
Tanghe, S.; Vanroose, G.; Van Soom, A. et al

in Reproduction (2005), 130(2), 251-259

The purpose of the present study was to identify a potential interference of bovine herpesvirus-1 (BoHV-1) with sperm-oocyte interactions during bovine in vitro fertilization. An inhibition of almost 70 ... [more ▼]

The purpose of the present study was to identify a potential interference of bovine herpesvirus-1 (BoHV-1) with sperm-oocyte interactions during bovine in vitro fertilization. An inhibition of almost 70% of sperm-zona binding was observed when bovine cumulus-denuded oocytes were inseminated in the presence of 10(7) 50% tissue culture infective dose/ml BoHV-1. The inhibitory effect of BoHV-1 on sperm-zona binding was mediated by an interaction of the virus with spermatozoa, but not with oocytes. Treatment of spermatozoa with BoHV-1, however, did not affect sperm motility and acrosomal status. Antiserum against RoHV-1 prevented the virus-induced inhibition of sperm-zona binding, indicating that BoHV-1 itself affects the fertilization process. In order to investigate which BoHV-1 glycoprotein(s) are responsible for the virus-sperm interaction, BoHV-1 was treated with monoclonal antibodies against the viral glycoproteins gB, gC, gD and gH prior to insemination. Anti-gC completely prevented the inhibitory effect of BoHV-1 on sperm-zona binding, while anti-gD caused a reduction of this inhibition. Further evidence for the involvement of gC and gD in the virus-sperm interaction was provided by the fact that purified gC and gD decreased sperm-zona binding in a dose-dependent way with gC being more effective than gD. These results indicated that BoHV-1 inhibits bovine sperm-zona binding by interacting with spermatozoa. The binding of BoHV-1 to a spermatozoon is mediated by the viral glycoproteins gC and gD, and therefore seems to be comparable with the mechanisms of BoHV-1 attachment to its natural host cell. [less ▲]

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See detailPoint mutations in an infectious bovine viral diarrhoea virus type 2 cDNA transcript that yields an attenuated and protective viral progeny
Dehan, Pierre ULg; Couvreur, B.; Hamers, C. et al

in Vaccine (2005), 23(33), 4236-4246

An infectious cDNA clone of the hypervirulent bovine viral diarrhoea virus (BVDV) strain 890 (isolate 256) was produced by a streamlined PCR procedure. As compared to the published sequence of strain 890 ... [more ▼]

An infectious cDNA clone of the hypervirulent bovine viral diarrhoea virus (BVDV) strain 890 (isolate 256) was produced by a streamlined PCR procedure. As compared to the published sequence of strain 890, the nucleotide sequencing of cloned cDNA corresponding to isolate 256 revealed several mutations seven of which were attributed to the cloning procedure. The infectious transcript was transfected into permissive cells and led to viral multiplication (AvrII+ strain). In vitro, viral titres reached by the parental strain exceed those of the AvrII+ strain by more than one order of magnitude. The latter was clearly less virulent to young calves as indicated by clinical, haematological and virological parameters. Thirty-four days after inoculation with AvrII+ strain, calves were challenged with the virulent parental strain. The animals were protected as compared to unvaccinated controls. Therefore, our approach led to the production of an attenuated strain with potential use as a vaccine strain and will be useful for studies of virulence determinants in BVDV-2. (c) 2005 Elsevier Ltd. All rights reserved. [less ▲]

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See detailReal Time RT-PCR for the detection and quantitation of bovine respiratory syncytial virus.
Boxus, Mathieu ULg; Letellier, C.; Kerkhofs, P.

in Journal of Virological Methods (2005), 125(2), 125-30

A quantitative Real Time RT-PCR assay was developed to detect and quantify bovine respiratory syncytial virus (BRSV) in the respiratory tract of infected animals. A pair of primers and a TaqMan probe ... [more ▼]

A quantitative Real Time RT-PCR assay was developed to detect and quantify bovine respiratory syncytial virus (BRSV) in the respiratory tract of infected animals. A pair of primers and a TaqMan probe targeting conserved regions of the nucleoprotein gene of BRSV were designed. The detection limit of the assay was shown to be 10(3) RNA copies and standard curve demonstrated a linear range from 10(3) to 10(8) copies as well as an excellent reproducibility. The efficiency of the BRSV Real Time RT-PCR was then assessed by detecting BRSV in lungs, tracheas and bronchoalveaolar fluids (BAL) samples of experimentally infected calves. The assay was shown to be 100 times more sensitive than conventional RT-PCR and was more efficient for BRSV diagnosis. Finally, the Real Time RT-PCR was used to quantify BRSV load in BAL fluids of four experimentally infected calves for 14 days. The high sensitivity, rapidity and reproducibility of the BRSV Real Time RT-PCR make this method suitable for diagnostic and for the evaluation of the efficiency of new vaccines. [less ▲]

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See detailDeux protocoles d’hyperimmunisation au moyen de vaccins marqués réduisent l’incidence de séroconversion envers l’herpèsvirus bovin 1 en cheptels laitiers : résultats d’une étude sur le terrain
Dispas, M.; Lemaire, Mylène; Speybroeck, N. et al

in Annales de Médecine Vétérinaire (2004), 148(1), 47-61

A 28 months long cohort study was organized in dairy herds in Belgium, to assess the efficacy of hyperimmunisation as a tool for the control of infectious bovine rhinotracheitis. Two protocols of ... [more ▼]

A 28 months long cohort study was organized in dairy herds in Belgium, to assess the efficacy of hyperimmunisation as a tool for the control of infectious bovine rhinotracheitis. Two protocols of hyperimmunisation in which glycoprotein-E deleted marker vaccines were repeatedly administered were compared to a positive control group in which the usual vaccination protocols were authorised. The two hyperimmunisation protocols differed in the primovaccination : the first group was treated with an attenuated vaccine firstly given intra-nasally then by intramuscular route whereas the second group was given an inactivated vaccine by subcutaneous injection. Afterwards, booster vaccinations were the same in both groups : an inactivated vaccine was administered by subcutaneous route every 6 months. In the control group, as a rule, part of the herd was vaccinated annually. For each group, 6 half-yearly reports specify : 1. the evolution of the population, categorized by birth half-year, 2. the incidence of seroconversion against gE in the cohorts and 3. the evolution of the gE seroprevalence. The survival curves of the hyperimmunised groups show a significantly higher proportion (P < 0,001) of animals remaining seronegative against glycoprotein- E compared to the positive control group. No significant difference was shown between the two protocols of hyperimmunisation. Both of them could then be used as tools for the control of infectious bovine rhinotracheitis. [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 detailAdvantages and disadvantages of a control programme against infectious bovine rhinotracheitis in Belgium
Limbourg, B.; Kerkhofs, P.; Massard, C. et al

in Annales de Médecine Vétérinaire (2002), 146(2, APR-MAY), 57-69

A working party of the "Association d'Epidemiologie et de Sante Animale" assessed the strategy for a control of infectious bovine rhinotracheitis (IBR) in Belgium and studied its feasability and the ... [more ▼]

A working party of the "Association d'Epidemiologie et de Sante Animale" assessed the strategy for a control of infectious bovine rhinotracheitis (IBR) in Belgium and studied its feasability and the different programmes to be applied. Epidemiology of IBR in Belgium, vaccination, diagnostic methods, economic aspects of IBR control, Belgian laws regarding IBR and the motivation of people in the field were described. The advantages and disadvantages of three programmes were analysed: to maintain the current situation, to protect cattle against clinical disease and to control and eradicate IBR. [less ▲]

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See detailBovine Leukemia Virus Su Protein Interacts With Zinc, And Mutations Within Two Interacting Regions Differentially Affect Viral Fusion And Infectivity In Vivo
Gatot, Js.; Callebaut, I.; Van Lint, C. et al

in Journal of Virology (2002), 76(16),

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See detailInhibition Of Histone Deacetylases Induces Bovine Leukemia Virus Expression In Vitro And In Vivo
Merezak, C.; Reichert, M.; Van Lint, C. et al

in Journal of Virology (2002), 76(10),

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See detailIncreased Cell Proliferation, But Not Reduced Cell Death, Induces Lymphocytosis In Bovine Leukemia Virus-Infected Sheep
Debacq, C.; Asquith, B.; Kerkhofs, P. et al

in Proceedings of the National Academy of Sciences of the United States of America (2002), 99(15),

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See detailDiversity among Bovine Pestiviruses
Hamers, C.; Dehan, Pierre ULg; Couvreur, B. et al

in Veterinary Journal (2001), 161(2), 112-22

Bovine viral diarrhoea virus (BVDV) isolates are characterized by an important genetic, antigenic and pathogenic diversity. The emergence of new hypervirulent BVDV strains in North America has provided ... [more ▼]

Bovine viral diarrhoea virus (BVDV) isolates are characterized by an important genetic, antigenic and pathogenic diversity. The emergence of new hypervirulent BVDV strains in North America has provided clear evidence of pathogenic differences between BVDV strains. The origin of BVDV diversity is related to high mutation rate occurring in RNA viruses but the consequences of mutations obviously depend on the genes which are involved. Mutations in genes encoding for structural proteins of immunological importance may have practical implications.Knowledge of BVDV diversity is important for understanding the wide variety of pathogenesis of diseases caused by the virus, for monitoring the epidemiology of the different types and for the design of optimum laboratory tests and vaccines.This review focuses on the origin and consequences of BVDV diversity with regard to pathogenesis, biotypes, and antigenic and genetic variations. [less ▲]

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See detailRecommandations de l’association d’épidémiologie et de santé animale concernant la lutte contre la rhinotrachéite infectieuse bovine (IBR) en Belgique
Limbourg, B.; Kerkhofs, P.; Massard, C. et al

in Annales de Médecine Vétérinaire (2001), 147

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See detailCell turnover in BLV-infected sheep.
Debacq, C.; Peremans, T.; Kerkhofs, P. et al

in AIDS Research and Human Retroviruses (2001), 17(1), 13

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See detailSuboptimal Enhancer Sequences Are Required For Efficient Bovine Leukemia Virus Propagation In Vivo: Implications For Viral Latency
Merezak, C.; Pierreux, C.; Adam, E. et al

in Journal of Virology (2001), 75(15),

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See detailAvancées récentes en biologie moléculaire du virus de la diarrhée virale bovine
Dehan, Pierre ULg; Hamers, C.; Couvreur, B. et al

in Annales de Médecine Vétérinaire (2001), 145

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See detailDifferences in Experimental Virulence of Bovine Viral Diarrhoea Viral Strains Isolated from Haemorrhagic Syndromes
Hamers, C.; Couvreur, B.; Dehan, Pierre ULg et al

in Veterinary Journal (2000), 160(3), 250-8

In the late 1980s, a new hypervirulent and epidemic form of bovine viral diarrhoea virus (BVDV) infection appeared in North America. A similar but sporadic syndrome was later reported in Europe. To ... [more ▼]

In the late 1980s, a new hypervirulent and epidemic form of bovine viral diarrhoea virus (BVDV) infection appeared in North America. A similar but sporadic syndrome was later reported in Europe. To compare the pathogenic characters of the North American and European hypervirulent strains, we inoculated BVDV naive calves with BVDV strains isolated from haemorrhagic syndromes originating in Belgium, France and the USA. The experimental procedure comprised daily clinical examination and measurement of blood and virological parameters.The American BVD890/256 strain induced severe thrombocytopaenia, profuse diarrhoea and pneumonia in all calves, indicating that hypervirulent BVDV could be the primary infectious agent of pneumonia. Interestingly, a strong correlation was observed between the intense viraemia and a decreased platelet count. None of the European strains tested induced significant pathological signs, although isolated from cases presenting haemorrhagic syndrome. [less ▲]

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See detailGenetic Determinants Of Bovine Leukemia Virus Pathogenesis
Willems, Luc ULg; Burny, A.; Collete, Delphine et al

in Aids Research and Human Retroviruses (2000), 16(16), 1787-95

The understanding of HTLV-induced disease is hampered by the lack of a suitable animal model allowing the study of both viral replication and leukemogenesis in vivo. Although valuable information has been ... [more ▼]

The understanding of HTLV-induced disease is hampered by the lack of a suitable animal model allowing the study of both viral replication and leukemogenesis in vivo. Although valuable information has been obtained in different species, such as rabbits, mice, rats, and monkeys, none of these systems was able to conciliate topics as different as viral infectivity, propagation within the host, and generation of leukemic cells. An alternate strategy is based on the understanding of diseases induced by viruses closely related to HTLV-1, like bovine leukemia virus (BLV). Both viruses indeed belong to the same subfamily of retroviruses, harbor a similar genomic organization, and infect and transform cells of the hematopoietic system. The main advantage of the BLV system is that it allows direct experimentation in two different species, cattle and sheep. [less ▲]

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See detailNatural case of bovine herpesvirus 1 meningoencephalitis in an adult cow.
Roels, S.; Charlier, G.; Letellier, C. et al

in Veterinary Record : Journal of the British Veterinary Association (2000), 146(20), 586-8

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See detailLong-Term Protection Against Bovine Leukaemia Virus Replication In Cattle And Sheep
Kerkhofs, P.; Gatot, Js.; Knapen, K. et al

in Journal of General Virology (2000), 81

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See detailBovine leukemia virus as a model for human T-cell leukemia virus
Willems, Luc ULg; Burny, A.; Dangoisse, O. et al

in Current Topics in Virology (1999)

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