title: Specific regulation of the chemokine response to viral hemorrhagic septicemia virus at the entry site.
abstract: The fin bases constitute the main portal of rhabdovirus entry into rainbow trout (Oncorhynchus mykiss), and replication in this first site strongly conditions the outcome of the infection. In this context, we studied the chemokine response elicited in this area in response to viral hemorrhagic septicemia virus (VHSV), a rhabdovirus. Among all the rainbow trout chemokine genes studied, only the transcription levels of CK10 and CK12 were significantly upregulated in response to VHSV. As the virus had previously been shown to elicit a much stronger chemokine response in internal organs, we compared the effect of VHSV on the gills, another mucosal site which does not constitute the main site of viral entry or rhabdoviral replication. In this case, a significantly stronger chemokine response was triggered, with CK1, CK3, CK9, and CK11 being upregulated in response to VHSV and CK10 and CK12 being down-modulated by the virus. We then conducted further experiments to understand how these different chemokine responses of mucosal tissues could correlate with their capacity to support VHSV replication. No viral replication was detected in the gills, while at the fin bases, only the skin and the muscle were actively supporting viral replication. Within the skin, viral replication took place in the dermis, while viral replication was blocked within epidermal cells at some point before protein translation. The different susceptibilities of the different skin layers to VHSV correlated with the effect that VHSV has on their capacity to secrete chemotactic factors. Altogether, these results suggest a VHSV interference mechanism on the early chemokine response at its active replication sites within mucosal tissues, a possible key process that may facilitate viral entry.
authors.affiliation: Centro de Investigación en Sanidad Animal (CISA-INIA), Carretera de Algete a El Casar km. 8.1, Valdeolmos 28130, Madrid, Spain.
authors.forename: Jana
authors.initials: J
authors.lastname: Montero
authors.forename: Jessica
authors.initials: J
authors.lastname: Garcia
authors.forename: M Camino
authors.initials: MC
authors.lastname: Ordas
authors.forename: Isabel
authors.initials: I
authors.lastname: Casanova
authors.forename: Antonia
authors.initials: A
authors.lastname: Gonzalez
authors.forename: Alberto
authors.initials: A
authors.lastname: Villena
authors.forename: Julio
authors.initials: J
authors.lastname: Coll
authors.forename: Carolina
authors.initials: C
authors.lastname: Tafalla
mesh_terms: D058500:Animal Fins / Q000276:immunology / Q000821:virology; D000818:Animals; D018925:Chemokines / Q000096:biosynthesis / Q000276:immunology*; D005393:Fish Diseases / Q000276:immunology* / Q000821:virology; D020869:Gene Expression Profiling; D005880:Gills / Q000276:immunology / Q000821:virology; D029141:Novirhabdovirus / Q000276:immunology*; D017686:Oncorhynchus mykiss; D018353:Rhabdoviridae Infections / Q000276:immunology / Q000662:veterinary*; D012867:Skin / Q000821:virology; D014779:Virus Replication
chemical_list: D018925:Chemokines