title: [New cold-adapted donor strains for live influenza vaccine].
abstract: Cold-adapted (CA) strains A/Krasnodar/35 and B/Victoria/63 were isolated using passages of A/Krasnodar/101/59 and B/Victoria/2/87 wild type strains at low temperatures. The resulting CA strains possessed TS and CA phenotypes and had a reduced ability to reproduce in mouse lungs and nasal turbinates. They displayed a high protective efficacy in experiments on mice. The two CA strains reproduced well in chick embryos and MDCK cell line without change of TS and CA markers. The CA A/Krasnodar/35 strain during passages at low temperature acquired 13 mutations in the 6 internal genes, 8 of those mutations led to amino acid changes. The CA B/Victoria/63 strain acquired 8 mutations in the internal genes, 6 of which led to amino acid changes. The intranasal vaccination of mice with the CA A/Krasnodar/35 strain led to a transitory suppression of various lymphocyte subpopulations, as well as to an increase in the number of some other cell types. The CA strains in question may be used in the future as attenuation donors for live influenza vaccines.
authors.forename: Iu Z
authors.initials: IuZ
authors.lastname: Gendon
authors.forename: S G
authors.initials: SG
authors.lastname: Markushin
authors.forename: T M
authors.initials: TM
authors.lastname: Tsfasman
authors.forename: I I
authors.initials: II
authors.lastname: Akopova
authors.forename: N K
authors.initials: NK
authors.lastname: Akhmatova
authors.forename: I B
authors.initials: IB
authors.lastname: Koptiaeva
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D019943:Amino Acid Substitution; D000818:Animals; D002460:Cell Line; D002642:Chick Embryo; D003080:Cold Temperature; D004285:Dogs; D006801:Humans; D053121:Influenza A Virus, H2N2 Subtype / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D007252:Influenza Vaccines / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D051379:Mice; D009154:Mutation; D014613:Vaccines, Attenuated / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology
chemical_list: D007252:Influenza Vaccines; D014613:Vaccines, Attenuated