title: Covariance of lowered capacity to induce interferon in human leukocytes and temperature sensitivity of type 3 poliovirus.
abstract: Attenuated poliovirus strains induce less interferon-alpha (IFN-alpha) in human leukocyte cultures than their parental wild-type strains or other neurovirulent strains. We have used a set of type 3 Leon/Sabin recombinant poliovirus strains to show that production of IFN in this system is closely associated with the genomic region that codes for capsid protein VP3; a mutation in this gene also causes the temperature sensitivity of the attenuated Sabin 3 strain and is partly responsible for the loss of neurovirulence of this vaccine strain. Sixteen independent poliovirus isolates, derived from the Sabin 3 virus but showing in vitro and in vivo markers of neurovirulence, were also tested. These gave IFN yields equivalent to or higher than those obtained with the neurovirulent Leon type 3 poliovirus. The relatively low IFN yields with the Sabin 3 virus seem not to be a direct consequence of its temperature sensitivity, but the two properties coincide with all the type 3 poliovirus strains tested.
authors.affiliation: Enterovirus Laboratory and Molecular Biology Unit, National Public Health Institute, Helsinki, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Hovi
authors.forename: A
authors.initials: A
authors.lastname: Pitkäranta
authors.forename: A
authors.initials: A
authors.lastname: Macadam
authors.forename: P
authors.initials: P
authors.lastname: Minor
authors.forename: J
authors.initials: J
authors.lastname: Almond
mesh_terms: D002213:Capsid / Q000235:genetics; D006801:Humans; D007372:Interferons / Q000096:biosynthesis*; D007962:Leukocytes / Q000378:metabolism*; D017955:Poliovirus / Q000235:genetics / Q000472:pathogenicity*; D011055:Poliovirus Vaccine, Oral / Q000276:immunology; D012367:RNA, Viral / Q000235:genetics; D013696:Temperature; D014774:Virulence / Q000276:immunology
chemical_list: D011055:Poliovirus Vaccine, Oral; D012367:RNA, Viral; D007372:Interferons