title: Susceptibility to flavivirus-specific antiviral response of Oas1b affects the neurovirulence of the Far-Eastern subtype of tick-borne encephalitis virus.
abstract: Tick-borne encephalitis virus (TBEV) is a zoonotic agent that causes fatal encephalitis in humans. 2'-5'-oligoadenylate synthetase 1b (Oas1b) has been identified as a flavivirus resistance gene, but most inbred laboratory mice do not possess a functional Oas1b gene. In this study, a congenic strain carrying a functional Oas1b gene, B6.MSM-Oas, was used to evaluate the pathogenicity of Far-Eastern TBEV. Although intracerebral infection of B6.MSM-Oas mice by Oshima 5-10 resulted in limited signs of illness, infection by Sofjin-HO resulted in death with severe neurologic signs. While Oshima 5-10 was cleared from the brain, Sofjin-HO was not cleared despite a similar level of expression of the intact Oas1b gene. Necrotic neurons with viral antigens and inflammatory reactions were observed in the brain infected with Sofjin-HO. These data indicate that the different susceptibility to the antiviral activity of Oas1b resulted in a difference in neurovirulence in the two TBEV strains.
authors.affiliation: Laboratory of Public Health, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18 nishi-9, kita-ku, Sapporo, Hokkaido 060-0818, Japan. kyoshii@vetmed.hokudai.ac.jp
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yoshii
authors.forename: Kanako
authors.initials: K
authors.lastname: Moritoh
authors.forename: Noriyo
authors.initials: N
authors.lastname: Nagata
authors.forename: Kana
authors.initials: K
authors.lastname: Yokozawa
authors.forename: Mizuki
authors.initials: M
authors.lastname: Sakai
authors.forename: Nobuya
authors.initials: N
authors.lastname: Sasaki
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kariwa
authors.forename: Takashi
authors.initials: T
authors.lastname: Agui
authors.forename: Ikuo
authors.initials: I
authors.lastname: Takashima
mesh_terms: D015088:2',5'-Oligoadenylate Synthetase / Q000276:immunology*; D000818:Animals; D001921:Brain / Q000473:pathology / Q000821:virology; D004669:Encephalitis Viruses, Tick-Borne / Q000276:immunology* / Q000472:pathogenicity*; D018792:Encephalitis, Viral / Q000276:immunology / Q000473:pathology / Q000821:virology; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D016019:Survival Analysis
chemical_list: C509914:Oas1b protein, mouse; D015088:2',5'-Oligoadenylate Synthetase