tetano
Editor, Senior Moderator
Vaccine. 2015 Sep 22. pii: S0264-410X(15)01314-6. doi: 10.1016/j.vaccine.2015.09.038. [Epub ahead of print]
[h=1]Cold adaptation generates mutations associated with the growth of influenza B vaccine viruses.[/h] Kim H[SUP]1[/SUP], Velkov T[SUP]2[/SUP], Camuglia S[SUP]3[/SUP], Rockman SP[SUP]4[/SUP], Tannock GA[SUP]5[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Seasonal inactivated influenza vaccines are usually trivalent or quadrivalent and are prepared from accredited seed viruses. Yields of influenza A seed viruses can be enhanced by gene reassortment with high-yielding donor strains, but similar approaches for influenza B seed viruses have been largely unsuccessful. For vaccine manufacture influenza B seed viruses are usually adapted for high-growth by serial passage. Influenza B antigen yields so obtained are often unpredictable and selection of influenza B seed viruses by this method can be a rate-limiting step in seasonal influenza vaccine manufacture. We recently have shown that selection of stable cold-adapted mutants from seasonal epidemic influenza B viruses is associated with improved growth. In this study, specific mutations were identified that were responsible for growth enhancement as a consequence of adaptation to growth at lower temperatures. Molecular analysis revealed that the following mutations in the HA, NP and NA genes are required for enhanced viral growth: G156/N160 in the HA, E253, G375 in the NP and T146 in the NA genes. These results demonstrate that the growth of seasonal influenza B viruses can be optimized or improved significantly by specific gene modifications.
Copyright ? 2015. Published by Elsevier Ltd.
[h=4]KEYWORDS:[/h] Cold adaptation; Growth; Influenza B virus; Mutations; Vaccine
PMID: 26407922 [PubMed - as supplied by publisher]
[h=1]Cold adaptation generates mutations associated with the growth of influenza B vaccine viruses.[/h] Kim H[SUP]1[/SUP], Velkov T[SUP]2[/SUP], Camuglia S[SUP]3[/SUP], Rockman SP[SUP]4[/SUP], Tannock GA[SUP]5[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Seasonal inactivated influenza vaccines are usually trivalent or quadrivalent and are prepared from accredited seed viruses. Yields of influenza A seed viruses can be enhanced by gene reassortment with high-yielding donor strains, but similar approaches for influenza B seed viruses have been largely unsuccessful. For vaccine manufacture influenza B seed viruses are usually adapted for high-growth by serial passage. Influenza B antigen yields so obtained are often unpredictable and selection of influenza B seed viruses by this method can be a rate-limiting step in seasonal influenza vaccine manufacture. We recently have shown that selection of stable cold-adapted mutants from seasonal epidemic influenza B viruses is associated with improved growth. In this study, specific mutations were identified that were responsible for growth enhancement as a consequence of adaptation to growth at lower temperatures. Molecular analysis revealed that the following mutations in the HA, NP and NA genes are required for enhanced viral growth: G156/N160 in the HA, E253, G375 in the NP and T146 in the NA genes. These results demonstrate that the growth of seasonal influenza B viruses can be optimized or improved significantly by specific gene modifications.
Copyright ? 2015. Published by Elsevier Ltd.
[h=4]KEYWORDS:[/h] Cold adaptation; Growth; Influenza B virus; Mutations; Vaccine
PMID: 26407922 [PubMed - as supplied by publisher]