Previous Article | Next Article 
Journal of Virology, June 2005, p. 6763-6771, Vol. 79, No. 11
0022-538X/05/$08.00+0 doi:10.1128/JVI.79.11.6763-6771.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
Improvement of Influenza A/Fujian/411/02 (H3N2) Virus Growth in Embryonated Chicken Eggs by Balancing the Hemagglutinin and Neuraminidase Activities, Using Reverse Genetics
Bin Lu, Helen Zhou, Dan Ye, George Kemble, and Hong Jin*MedImmune Vaccines, Inc., 297 N. Bernardo Ave., Mountain View, California 94043
Received 6 December 2004/ Accepted 24 January 2005
The H3N2 influenza A/Fujian/411/02-like virus strains that circulated during the 2003-2004 influenza season caused influenza epidemics. Most of the A/Fujian/411/02 virus lineages did not replicate well in embryonated chicken eggs and had to be isolated originally by cell culture. The molecular basis for the poor replication of A/Fujian/411/02 virus was examined in this study by the reverse genetics technology. Two antigenically related strains that replicated well in embryonated chicken eggs, A/Sendai-H/F4962/02 and A/Wyoming/03/03, were compared with the prototype A/Fujian/411/02 virus. A/Sendai differed from A/Fujian by three amino acids in the neuraminidase (NA), whereas A/Wyoming differed from A/Fujian by five amino acids in the hemagglutinin (HA). The HA and NA segments of these three viruses were reassorted with cold-adapted A/Ann Arbor/6/60, the master donor virus for the live attenuated type A influenza vaccines (FluMist). The HA and NA residues differed between these three H3N2 viruses evaluated for their impact on virus replication in MDCK cells and in embryonated chicken eggs. It was determined that replication of A/Fujian/411/02 in eggs could be improved by either changing minimum of two HA residues (G186V and V226I) to increase the HA receptor-binding ability or by changing a minimum of two NA residues (E119Q and Q136K) to lower the NA enzymatic activity. Alternatively, recombinant A/Fujian/411/02 virus could be adapted to grow in eggs by two amino acid substitutions in the HA molecule (H183L and V226A), which also resulted in the increased HA receptor-binding activity. Thus, the balance between the HA and NA activities is critical for influenza virus replication in a different host system. The HA or NA changes that increased A/Fujian/411/02 virus replication in embryonated chicken eggs were found to have no significant impact on antigenicity of these recombinant viruses. This study demonstrated that the reverse genetics technology could be used to improve the manufacture of the influenza vaccines.
* Corresponding author. Mailing address: MedImmune Vaccines, Inc., 297 N. Bernardo Ave., Mountain View, CA 94043. Phone: (650) 603-2367. Fax: (650) 603-3367. E-mail: jinh{at}medimmune.com.
Journal of Virology, June 2005, p. 6763-6771, Vol. 79, No. 11
0022-538X/05/$08.00+0 doi:10.1128/JVI.79.11.6763-6771.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Murakami, S., Horimoto, T., Mai, L. Q., Nidom, C. A., Chen, H., Muramoto, Y., Yamada, S., Iwasa, A., Iwatsuki-Horimoto, K., Shimojima, M., Iwata, A., Kawaoka, Y.
(2008). Growth Determinants for H5N1 Influenza Vaccine Seed Viruses in MDCK Cells. J. Virol.
82: 10502-10509
[Abstract] [Full Text] -
McDonald, N. J., Smith, C. B., Cox, N. J.
(2007). Antigenic drift in the evolution of H1N1 influenza A viruses resulting from deletion of a single amino acid in the haemagglutinin gene. J. Gen. Virol.
88: 3209-3213
[Abstract] [Full Text]
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»