title: Physiological change under OsHV-1 contamination in Pacific oyster Crassostrea gigas through massive mortality events on fields.
abstract: BACKGROUND
  Massive mortalities have been observed in France since 2008 on spat and juvenile Pacific oysters, Crassostrea gigas. A herpes virus called OsHV-1, easily detectable by PCR, has been implicated in the mortalities as demonstrated by the results of numerous field studies linking mortality with OsHV-1 prevalence. Moreover, experimental infections using viral particles have documented the pathogenicity of OsHV-1 but the physiological responses of host to pathogen are not well known.
  
  
  RESULTS
  The aim of this study was to understand mechanisms brought into play against the virus during infection in the field. A microarray assay has been developed for a major part of the oyster genome and used for studying the host transcriptome across mortality on field. Spat with and without detectable OsHV-1 infection presenting or not mortality respectively were compared by microarray during mortality episodes. In this study, a number of genes are regulated in the response to pathogen infection on field and seems to argue to an implication of the virus in the observed mortality. The result allowed establishment of a hypothetic scheme of the host cell's infection by, and response to, the pathogen.
  
  
  CONCLUSIONS
  This response shows a "sensu stricto" innate immunity through genic regulation of the virus OsHV-1 life cycle, but also others biological processes resulting to complex interactions between host and pathogens in general.
authors.affiliation: CNRS INEE, BioMEA, Caen Cedex 14 032, France. aude.jouaux@unicaen.fr.
authors.forename: Aude
authors.initials: A
authors.lastname: Jouaux
authors.forename: Maxime
authors.initials: M
authors.lastname: Lafont
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Blin
authors.forename: Maryline
authors.initials: M
authors.lastname: Houssin
authors.forename: Michel
authors.initials: M
authors.lastname: Mathieu
authors.forename: Christophe
authors.initials: C
authors.lastname: Lelong
mesh_terms: D000818:Animals; D049896:Crassostrea / Q000235:genetics* / Q000276:immunology / Q000502:physiology / Q000821:virology; D020224:Expressed Sequence Tags; D005602:France; D006564:Herpesviridae / Q000302:isolation & purification / Q000472:pathogenicity*; D006566:Herpesviridae Infections / Q000662:veterinary*; D054884:Host-Pathogen Interactions; D007113:Immunity, Innate; D020411:Oligonucleotide Array Sequence Analysis; D059467:Transcriptome