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See detailIxodes ticks belonging to the Ixodes ricinus complex encode a family of anticomplement proteins.
Daix, Virginie ULg; Schroeder, Hélène ULg; Praet, N. et al

in Insect Molecular Biology (2007), 16(2), 155-66

The alternative pathway of complement is an important innate defence against pathogens including ticks. This component of the immune system has selected for pathogens that have evolved countermeasures ... [more ▼]

The alternative pathway of complement is an important innate defence against pathogens including ticks. This component of the immune system has selected for pathogens that have evolved countermeasures. Recently, a salivary protein able to inhibit the alternative pathway was cloned from the American tick Ixodes scapularis (Valenzuela et al., 2000; J. Biol. Chem. 275, 18717-18723). Here, we isolated two different sequences, similar to Isac, from the transcriptome of I. ricinus salivary glands. Expression of these sequences revealed that they both encode secreted proteins able to inhibit the complement alternative pathway. These proteins, called I. ricinus anticomplement (IRAC) protein I and II, are coexpressed constitutively in I. ricinus salivary glands and are upregulated during blood feeding. Also, we demonstrated that they are the products of different genes and not of alleles of the same locus. Finally, phylogenetic analyses demonstrate that ticks belonging to the Ixodes ricinus complex encode a family of relatively small anticomplement molecules undergoing diversification by positive Darwinian selection. [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 detailEvolution of Bovine herpesvirus 4: recombination and transmission between African buffalo and cattle
Dewals, Benjamin G ULg; Thirion, Muriel ULg; Markine-Goriaynoff, N. et al

in Journal of General Virology (2006), 87(Pt 6), 1509-1519

Bovine herpesvirus 4 (BoHV-4) has been isolated from cattle throughout the world, but virological and serological studies have suggested that the African buffalo is also a natural host for this virus. It ... [more ▼]

Bovine herpesvirus 4 (BoHV-4) has been isolated from cattle throughout the world, but virological and serological studies have suggested that the African buffalo is also a natural host for this virus. It has previously been found that the Bo17 gene of BoHV-4 was acquired from an ancestor of the African buffalo, probably around 1.5 million years ago. Analysis of the variation of the Bo17 gene sequence among BoHV-4 strains suggested a relatively ancient transmission of BoHV-4 from the buffalo to the Bos primigenius lineage, followed by a host-dependent split between zebu and taurine BoHV-4 strains. In the present study, the evolutionary history of BoHV-4 was investigated by analysis of five gene sequences from each of nine strains representative of the viral species: three isolated from African buffalo in Kenya and six from cattle from Europe, North America and India. No two gene sequences had the same evolutionary tree, indicating that recombination has occurred between divergent lineages; six recombination events were delineated for these sequences. Nevertheless, exchange has been infrequent enough that a clonal evolutionary history of the strains could be discerned, upon which the recombination events were superimposed. The dates of divergence among BoHV-4 lineages were estimated from synonymous nucleotide-substitution rates. The inferred evolutionary history suggests that African buffalo were the original natural reservoir of BoHV-4 and that there have been at least three independent transmissions from buffalo to cattle, probably via intermediate hosts and - at least in the case of North American strains - within the last 500 years. [less ▲]

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See detailGlycol chitosan improves the efficacy of intranasally administrated replication defective human adenovirus type 5 expressing glycoprotein D of bovine herpesvirus 1
Gogev, S.; de Fays, K.; Versali, Marie-France ULg et al

in Vaccine (2004), 22(15-16), 1946-1953

The ability of two soluble formulations, namely chitosan and glycol chitosan, when used as an intranasal adjuvant, to improve the immunogenicity of an intranasal human adenovirus type 5 replication ... [more ▼]

The ability of two soluble formulations, namely chitosan and glycol chitosan, when used as an intranasal adjuvant, to improve the immunogenicity of an intranasal human adenovirus type 5 replication defective expressing bovine herpesvirus 1 (BoHV-1) glycoprotein D based vaccine, was investigated in cattle. Their adjuvant effects on immune response by increasing clinical and especially virological protection against an intranasal BoHV-1 challenge were then evaluated. The best virological protection was obtained in calves immunized with the vaccine vector adjuvanted with glycol chitosan which decreased the challenge BoHV-1 virus excretion titres by 0.5-1.5 log when compared to those obtained in calves immunized with the vaccine vector alone or adjuvanted with chitosan. A slight difference in clinical scores was observed in calves immunized with the adjuvanted vaccine vector compared to calves immunized with the vaccine vector alone. The obtained data suggest that the tested soluble formulation of glycol chitosan has promising potential use as an intranasal adjuvant for recombinant viral vector vaccines in cattle. (C) 2003 Elsevier Ltd. All rights reserved. [less ▲]

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See detailL’herpèsvirus bovin 4
Markine-Goriaynoff, N.; Minner, F.; De Fays, K. et al

in Annales de Médecine Vétérinaire (2003), 147(4), 215-247

Bovine herpesvirus 4 (BoHV-4) belongs to the Herpesviridae family, Gammaherpesvirinae subfamily, Rhadinovirus genus like human herpesvirus 8 (HHV-8), the causative agent of Kaposi's sarcoma. BoHV-4 has a ... [more ▼]

Bovine herpesvirus 4 (BoHV-4) belongs to the Herpesviridae family, Gammaherpesvirinae subfamily, Rhadinovirus genus like human herpesvirus 8 (HHV-8), the causative agent of Kaposi's sarcoma. BoHV-4 has a worldwide distribution in the cattle population. It has been isolated from cattle showing various clinical signs as well as from healthy cattle. The interest of the scientific community for BoHV-4 is explained by two reasons. Firstly, BoHV-4 represents an homologous virus/host species model to study the biology of gammaherpesviruses. Secondly, the use of BoHV-4 as a recombinant vector for expression both in vitro and in vivo has been proposed. For these reasons, a considerable amount of data has been collected on this virus. In the present paper, the authors will present a general overview of the literature published on this virus addressing clinical, epidemiological and fundamental aspects of BoHV-4. Finally, in the light of their recent phylogenetic data, the authors will discuss the origin and the host species of BoHV-4 leading to the conclusion that this virus should be considered as a virus of the African buffalo rather than cattle. [less ▲]

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