title: Eight-plasmid system for rapid generation of influenza virus vaccines.
abstract: The antigenic variation of influenza A virus hemagglutinin (HA) and neuraminidase (NA) glycoproteins requires frequent changes in vaccine formulation. The classical method of creating influenza virus seed strains for vaccine production is to generate 6 + 2 reassortants that contain six genes from a high-yield virus, such as A/PR/8/34 (H1N1) and the HA and NA genes of the circulating strains. The techniques currently used are time-consuming because of the selection process required to isolate the reassortant virus. We generated the high-yield virus A/PR/8/34 (H1N1) entirely from eight plasmids. Its growth phenotype in embryonated chicken eggs was equivalent to that of the wild-type virus. By using this DNA-based cotransfection technique, we generated 6 + 2 reassortants that had the antigenic determinants of the influenza virus strains A/New Caledonia/20/99 (H1N1), A/Panama/2007/99 (H3N2), A/teal/HK/W312 (H6N1), and A/quail/HK/G1/97 (H9N2). Our findings demonstrate that the eight-plasmid system allows the rapid and reproducible generation of reassortant influenza A viruses for use in the manufacture of vaccines.
authors.affiliation: Department of Virology and Molecular Biology, St. Jude Children's Research Hospital, 332 North Lauderdale, Memphis, TN 38105-2794, USA.
authors.forename: Erich
authors.initials: E
authors.lastname: Hoffmann
authors.forename: Scott
authors.initials: S
authors.lastname: Krauss
authors.forename: Daniel
authors.initials: D
authors.lastname: Perez
authors.forename: Richard
authors.initials: R
authors.lastname: Webby
authors.forename: Robert G
authors.initials: RG
authors.lastname: Webster
mesh_terms: D000818:Animals; D000940:Antigenic Variation / Q000235:genetics; D001717:Birds / Q000821:virology; D002460:Cell Line; D002642:Chick Embryo; D002681:China; D003604:Czechoslovakia; D004274:DNA, Recombinant / Q000235:genetics; D004285:Dogs; D005814:Genes, Viral; D005822:Genetic Vectors / Q000235:genetics*; D009980:Influenza A virus / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification; D007252:Influenza Vaccines / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D009510:New Caledonia; D010176:Panama; D010641:Phenotype; D016865:Reassortant Viruses / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection; D014776:Virus Cultivation
chemical_list: D004274:DNA, Recombinant; D007252:Influenza Vaccines