title: Depletion of CD8 alpha cells from tissues of Atlantic salmon during the early stages of infection with high or low virulent strains of infectious salmon anaemia virus (ISAV).
abstract: The virulence of an infectious salmon anaemia virus (ISAV) isolate is influenced by the response of the host's immune system to virus infection. Here we report the fate of immune responsive cells in head kidney, spleen and gills of Atlantic salmon during infection with high and low virulent strains of ISAV. A comparison of real-time PCR detection of virus and immunohistochemical detection of immune responsive cells revealed that peak viral load was coincident with both an elevated presence of MHC class I cells and a marked depletion of CD8 alpha cells. There was a larger CD8 alpha population in tissues from salmon infected with the low virulent strain compared with tissues from salmon infected with the high virulent strain at early stages of infection. These findings suggest a protective role for the CD8 alpha cell population in immune defences against ISAV.
authors.affiliation: Department of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, Oslo, Norway. dyveke.hetland@nvh.no
authors.forename: Dyveke Lem
authors.initials: DL
authors.lastname: Hetland
authors.forename: Ole Bendik
authors.initials: OB
authors.lastname: Dale
authors.forename: Karsten
authors.initials: K
authors.lastname: Skjødt
authors.forename: Charles McL
authors.initials: CM
authors.lastname: Press
authors.forename: Knut
authors.initials: K
authors.lastname: Falk
mesh_terms: D000825:Animal Structures / Q000098:blood supply / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D000818:Animals; D016827:CD8 Antigens / Q000378:metabolism*; D005393:Fish Diseases / Q000276:immunology* / Q000821:virology; D005814:Genes, Viral; D005880:Gills / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D015395:Histocompatibility Antigens Class I / Q000378:metabolism; D046829:Isavirus / Q000235:genetics*; D008221:Lymphoid Tissue / Q000378:metabolism / Q000473:pathology; D009976:Orthomyxoviridae Infections / Q000276:immunology* / Q000662:veterinary; D012474:Salmon / Q000276:immunology / Q000821:virology; D013154:Spleen / Q000098:blood supply / Q000276:immunology / Q000378:metabolism / Q000473:pathology
chemical_list: D016827:CD8 Antigens; C409469:CD8 antigen, alpha chain; D015395:Histocompatibility Antigens Class I