The major portal of entry of koi herpesvirus in cyprinus carpio is the skin.
Costes, Bérénice ; ; Michel, Benjamin et al
in Journal of Virology (2009)
Koi herpesvirus (KHV), recently designated in the species Cyprinid Herpesvirus 3, is the causative agent of a lethal disease in koi and common carp. In the present study, we investigated the portal of ... [more ▼]
Koi herpesvirus (KHV), recently designated in the species Cyprinid Herpesvirus 3, is the causative agent of a lethal disease in koi and common carp. In the present study, we investigated the portal of entry of KHV in carp using bioluminescence imaging. Taking profit of the recent cloning of the KHV genome as a bacterial artificial chromosome (BAC), we produced a recombinant plasmid encoding a firefly luciferase (LUC) expression cassette inserted in the intergenic region between ORF 136 and ORF 137. Two viral strains were then reconstituted from the modified plasmid: the FL BAC 136 LUC excised strain and the FL BAC 136 LUC TK revertant strain encoding a disrupted and a wild-type thymidine kinase (TK) locus, respectively. In vitro, the two recombinant strains replicated comparably to the parental FL strain. The FL BAC 136 LUC TK revertant strain was shown in vitro to induce a bioluminescent signal allowing the detection of single positive cells as early as 24 hours post-infection; while in vivo, it induced KHV infection in carp that was indistinguishable from that induced by the parental FL strain. To identify the KHV portal of entry, carp were analyzed by bioluminescence imaging at different time post-infection with the FL BAC 136 LUC TK revertant strain. These analyses demonstrated that the skin of the fish, covering the fins and also the body, is the major portal of entry of KHV in carp. Finally, to further demonstrate the role of the skin as the KHV portal of entry, we constructed an original system nicknamed "U-tube" to perform per-cutaneous infection restricted to the posterior part of the fish. All the data obtained in the present study demonstrate that the skin and not the gills is the major portal of entry of KHV in carp. [less ▲]Detailed reference viewed: 83 (15 ULg)
Anchoring tick salivary anticomplement proteins IRAC I and IRAC II to membrane increases their immunogenicity
Gillet, Laurent ; Schroeder, Hélène ; et al
in Veterinary Research (2009), 40Detailed reference viewed: 34 (25 ULg)
Felid herpesvirus 1 glycoprotein G is a structural protein that mediates the binding of chemokines on the viral envelope.
Costes, Bérénice ; Thirion, Muriel ; Dewals, Benjamin G et al
in Microbes & Infection (2006), 8(11), 2657-67
Glycoprotein G (gG) orthologues have been described in several alphaherpesviruses. gG is expressed both as a membrane-anchored form on infected cells and as a secreted form. Recently, we reported that ... [more ▼]
Glycoprotein G (gG) orthologues have been described in several alphaherpesviruses. gG is expressed both as a membrane-anchored form on infected cells and as a secreted form. Recently, we reported that both forms of gG encoded by alphaherpesviruses infecting large herbivores and by Felid herpesvirus 1 (FeHV-1) bind with high affinity to a broad range of CXC, CC and C-chemokines. Based on the viral species, gG has been reported either as a structural or a non-structural protein. To date, the incorporation of FeHV-1 gG into virions has never been tested, nor the property of alphaherpesvirus structural gG to bind chemokines on the virion surface. In the present study, to address these questions, various FeHV-1 gG recombinant strains were produced using an original technique based on an infectious FeHV-1 BAC clone and restriction endonuclease mediated recombination. Using the recombinants produced, we were able to determine that FeHV-1 gG is a structural protein that acts as a chemokine-binding protein on the virion surface. In the light of these results, putative roles of gG in alphaherpesvirus infections are discussed, and an evolutionary scenario is proposed to explain the structural versus non-structural property of gG amongst alphaherpesviruses. [less ▲]Detailed reference viewed: 26 (7 ULg)
Evolution of Bovine herpesvirus 4: recombination and transmission between African buffalo and cattle
Dewals, Benjamin G ; Thirion, Muriel ; 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 ▲]Detailed reference viewed: 47 (7 ULg)
L'inventaire permanent des ressources ligneuses de la Region wallonne: principaux aspects methodologiques.
Rondeux, Jacques ; ; et al
A permanent forest inventory of the Walloon Region of Belgium is carried out since the beginning of 1994. This report provides an overview of the major required objectives, the methodology used and the ... [more ▼]
A permanent forest inventory of the Walloon Region of Belgium is carried out since the beginning of 1994. This report provides an overview of the major required objectives, the methodology used and the type of expected results. The important role of the forest at the regional level has made increasing demands upon adequate and reliable data useful for industrial development, forest policy, sustainable wood production and ecological considerations. The inventory that has been developed to fulfil such requirements is based upon a systematic sample (grid of 0.5 x 1 km : each point has a weight of 50 hectares) which covers about 530.000 hectares of wooded areas. The ground sample plots consist of 4 circular concentric subplots the radii of which are 2.25m, 4.5 m, 9 m and 18 m corresponding to areas in which only trees belonging to a fixed range of girth are considered. A large set of various data are collected : country-level data, plot-level data and tree-level data. A standardized programming system is used to perform calculations about volumes, areas and growth and to provide classifications "à la carte" presented in various forms such as summary tables, graphics or maps. [less ▲]Detailed reference viewed: 50 (6 ULg)