title: Composition of hemagglutinin and neuraminidase affects the antigen yield of influenza A(H1N1)pdm09 candidate vaccine viruses.
abstract: To improve the hemagglutinin (HA) antigen yield of influenza A(H1N1)pdm09 candidate vaccine viruses, we generated 7:1, 6:2, and 5:3 genetic reassortant viruses between wild-type (H1N1)pdm09 (A/California/7/2009) (Cal7) and a high-yielding master virus, A/Puerto Rico/8/34 (PR8). These viruses contained the HA; HA and neuraminidase (NA); and HA, NA, and M genes, respectively, derived from Cal7, on a PR8 backbone. The influence of the amino acid residue at position 223 in Cal7 HA on virus growth and HA antigen yield differed between these reassortant viruses. NIIDRG-7, a 7:1 virus possessing arginine at position 223, exhibited a 10-fold higher 50% egg infectious dose (EID(50)) (10.0 log(10)EID(50)/ml) than the 5:3 and 6:2 viruses. It also had 1.5- to 3-fold higher protein (13.8 μg/ml of allantoic fluids) and HA antigen (4.1 μg/ml of allantoic fluids) yields than the 5:3 and 6:2 viruses, which possessed identical Cal7 HA proteins. However, the HA antigen yield of the other 7:1 virus, which possessed glutamine at position 223 was 60% of that of NIIDRG-7. In addition, a novel 6:2 virus possessing Cal7 HA and the NA of A/Wisconsin/10/98 (a triple reassortant swine-like H1N1 virus), produced 107% of the HA yield of NIIDRG-7. In this study, we showed that the balance between HA and NA in the influenza A(H1N1)pdm09 virus affects its protein and antigen yield.
authors: Influenza Virus Research Center, National Institute of Infectious Diseases, Tokyo 208-0011, Japan.
authors: Masayuki
authors: M
authors: Shirakura
authors: Akira
authors: A
authors: Kawaguchi
authors: Masato
authors: M
authors: Tashiro
authors: Eri
authors: E
authors: Nobusawa
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000956:Antigens, Viral / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D002642:Chick Embryo; D005289:Ferrets; D006385:Hemagglutination Inhibition Tests; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics / Q000276:immunology*; D007252:Influenza Vaccines / Q000737:chemistry / Q000276:immunology; D007251:Influenza, Human / Q000276:immunology / Q000517:prevention & control*; D009439:Neuraminidase / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D016865:Reassortant Viruses / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D011993:Recombinant Fusion Proteins
chemical_list: D000956:Antigens, Viral; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007106:Immune Sera; D007252:Influenza Vaccines; D011993:Recombinant Fusion Proteins; D009439:Neuraminidase