title: Improving influenza virus backbones by including terminal regions of MDCK-adapted strains on hemagglutinin and neuraminidase gene segments.
abstract: Reverse genetics approaches can simplify and accelerate the process of vaccine manufacturing by combining the desired genome segments encoding the surface glycoproteins from influenza strains with genome segments (backbone segments) encoding internal and non-structural proteins from high-growth strains. We have developed three optimized high-growth backbones for use in producing vaccine seed viruses for group A influenza strains. Here we show that we can further enhance the productivity of our three optimized backbones by using chimeric hemagglutinin (HA) and neuraminidase (NA) genome segments containing terminal regions (non-coding regions (NCRs) and coding regions for the signal peptide (SP), transmembrane domain (TMD), and cytoplasmic tail (CT)) from two MDCK-adapted high growth strains (PR8x and Hes) and the sequences encoding the ectodomains of the A/Brisbane/10/2010 (H1N1) HA and NA proteins. Viruses in which both the HA and NA genome segments had the high-growth terminal regions produced higher HA yields than viruses that contained one WT and one chimeric HA or NA genome segment. Studies on our best-performing backbone indicated that the increases in HA yield were also reflected in an increase in HA content in partially purified preparations. Our results show that the use of chimeric HA and NA segments with high-growth backbones is a viable strategy that could improve influenza vaccine manufacturing. Possible mechanisms for the enhancement of HA yield are discussed.
authors: Novartis Vaccines and Diagnostics, 45 Sidney Street, Cambridge, MA 02139, United States. Electronic address: rcgomila@gmail.com.
authors: Raúl C
authors: RC
authors: Gomila
authors: Pirada
authors: P
authors: Suphaphiphat
authors: Casey
authors: C
authors: Judge
authors: Terika
authors: T
authors: Spencer
authors: Annette
authors: A
authors: Ferrari
authors: Yingxia
authors: Y
authors: Wen
authors: Giuseppe
authors: G
authors: Palladino
authors: Philip R
authors: PR
authors: Dormitzer
authors: Peter W
authors: PW
authors: Mason
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D002460:Cell Line; D004285:Dogs; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics / Q000276:immunology*; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics / Q000254:growth & development* / Q000276:immunology*; D007252:Influenza Vaccines / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D009439:Neuraminidase / Q000235:genetics / Q000276:immunology*; D059386:Reverse Genetics; D013678:Technology, Pharmaceutical / Q000379:methods; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology*; D014776:Virus Cultivation
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007252:Influenza Vaccines; D014764:Viral Proteins; C487630:NA protein, influenza A virus; D009439:Neuraminidase
keywords: Chimeras; Hemagglutinin; Influenza; Reverse genetics; Vaccine seeds