title: Study of the virulence of serotypes 4 and 9 of African horse sickness virus in IFNAR(-/-), Balb/C and 129 Sv/Ev mice.
abstract: African horse sickness virus (AHSV) is a double-stranded RNA virus which belongs to the family Reoviridae, genus Orbivirus. Recent studies have focused on the interferon-α/β receptor knock-out mice (IFNAR(-/-)) as a small animal laboratory for the development of AHSV vaccines. The aim of this work was to study in vivo the virulence of two strains of AHSV and to compare the outcome of the infection of three mouse strains. To address this, AHSV serotypes 4 (AHSV-4) and 9 (AHSV-9) were inoculated subcutaneously (SC) and intranasally (IN) in two immunocompetent mouse strains (Balb/C and 129 Sv/Ev (129 WT)) as well as IFNAR(-/-) mice (on 129 Sv/Ev genetic background). In IFNAR(-/-) mice, fatality up to 50% was measured and significantly more clinical signs were observed in comparison with SC inoculated immunocompetent mice. The observed clinical signs were significantly more severe after AHSV-4 infection, in particular in immunocompetent mice inoculated by IN route. Considering RNAemia, significantly higher viral loads were measured following AHSV-4 infection. In the organs of 129 WT inoculated by IN route, significantly higher viral loads were detected after AHSV-4 infection. Together the results support a higher virulence for AHSV-4 compared to AHSV-9 and a higher clinical impact following infections in IN inoculated mice, at least in the investigated strains. The study also brought indirect evidences for type I IFN involvement in the control of AHSV infection.
authors.affiliation: Veterinary Virology and Animal Viral Diseases, Fundamental and Applied Research on Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
authors.forename: Maria Ana
authors.initials: MA
authors.lastname: de la Grandière
authors.affiliation: Research Unit of Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULg), Fundamental and Applied Research on Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Dal Pozzo
authors.affiliation: Unit Enzootic and (Re-) Emerging Viral Disease, Operational Direction of Viral Diseases, Veterinary and Agrochemical Research Centre, Brussels, Belgium.
authors.forename: Marylène
authors.initials: M
authors.lastname: Tignon
authors.affiliation: Veterinary Virology and Animal Viral Diseases, Fundamental and Applied Research on Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
authors.forename: William
authors.initials: W
authors.lastname: Zonta
authors.affiliation: Veterinary Virology and Animal Viral Diseases, Fundamental and Applied Research on Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
authors.forename: Damien
authors.initials: D
authors.lastname: Thiry
authors.affiliation: Veterinary Virology and Animal Viral Diseases, Fundamental and Applied Research on Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
authors.forename: Axel
authors.initials: A
authors.lastname: Mauroy
authors.affiliation: Virological Platform Unit, Operational Direction of Viral Diseases, Veterinary and Agrochemical Research Centre, Brussels, Belgium.
authors.forename: Élisabeth
authors.initials: É
authors.lastname: Mathijs
authors.affiliation: Unit Enzootic and (Re-) Emerging Viral Disease, Operational Direction of Viral Diseases, Veterinary and Agrochemical Research Centre, Brussels, Belgium.
authors.forename: Ann Brigitte
authors.initials: AB
authors.lastname: Caij
authors.affiliation: Research Unit of Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULg), Fundamental and Applied Research on Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
authors.forename: Claude
authors.initials: C
authors.lastname: Saegerman
authors.affiliation: Veterinary Virology and Animal Viral Diseases, Fundamental and Applied Research on Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium. Electronic address: etienne.thiry@ulg.ac.be.
authors.forename: Étienne
authors.initials: É
authors.lastname: Thiry
mesh_terms: D000355:African Horse Sickness / Q000821:virology*; D000356:African Horse Sickness Virus / Q000472:pathogenicity*; D000818:Animals; D005260:Female; D006736:Horses; D016898:Interferon-alpha / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D012330:RNA, Double-Stranded; D053633:Receptor, Interferon alpha-beta / Q000235:genetics; D065288:Serogroup; D014774:Virulence
chemical_list: D016898:Interferon-alpha; D012330:RNA, Double-Stranded; D053633:Receptor, Interferon alpha-beta
keywords: African horse sickness virus; Mice; Orbivirus; Virulence