Structural and antigenic variance between novel influenza A/H1N1/2009 and influenza A/H1N1/2008 viruses

  • Shailendra K Saxena Centre for Cellular and Molecular Biology, Hyderabad
  • Niraj Mishra Centre for Cellular and Molecular Biology, Hyderabad
  • Rakhi Saxena Centre for Cellular and Molecular Biology, Hyderabad
  • ML Arvinda Swamy Centre for Cellular and Molecular Biology, Hyderabad
  • Pranshu Sahgal Centre for Cellular and Molecular Biology, Hyderabad
  • Shailja Saxena CSM Medical University (King George’s Medical College), Lucknow
  • Shrish Tiwari Centre for Cellular and Molecular Biology, Hyderabad
  • Asha Mathur Saraswati Medical and Dental College, Lucknow
  • Madhavan P Nair College of Medicine, Florida International University, Miami, FL
Keywords: Swine flu, Influenza A H1N1 2009, H1N1

Abstract

Background: The emergence of influenza A/H1N1/2009 is alarming. The severity of previous epidemics suggests that the susceptibility of the human population to H1N1 is directly proportional to the degree of changes in hemagglutinin/HA and neuraminidase/NA; therefore, H1N1/2009 and H1N1/2008 were analyzed for their sequence as well as structural divergence.

Methodology: The structural and sequence divergence of H1N1/2009 and H1N1/2008 strains were analyzed by aligning HA and NA amino acid sequences by using ClustalW and ESyPred3D software. To determine the variations in sites of viral attachment to host cells, a comparison between amino acid sequences of HA and NA glycosylation sites was performed with NetNGlyc software. The antigenic divergence was executed by CTL epitope prediction method. 

Results: The amino acid homology levels of H1N1/2009 were 20.32% and 18.73% compared to H1N1/2008 for HA and NA genes, respectively.  In spite of the high variation in HA and NA amino acid composition, there was no significant difference in their structures. Antigenic analysis proposes that great antigenic differences exist between both the viral strains, but no addition of a new site of glycosylation was observed.

Conclusions: To our knowledge, this is the first report suggesting that the circulating novel influenza virus A/H1N1/2009 attaches to the same glycosylation receptor sites as its predecessor influenza A/H1N1/2008 virus, but is antigenically different and may have the potential for initiating a significant pandemic. Our study may facilitate the development of better therapeutics and preventive strategies, as well as impart clues for novel H1N1 diagnostic and vaccine development.

Author Biography

Shailendra K Saxena, Centre for Cellular and Molecular Biology, Hyderabad

Senior Scientist & Leader

Laboratory of Infectious Diseases & Molecular Virology,

Centre for Cellular and Molecular Biology, Rm W 110,

(Council of Scientific & Industrial Research)

Uppal Road, Hyderabad 500 007 (AP),

INDIA.

Published
2009-11-26
How to Cite
1.
Saxena SK, Mishra N, Saxena R, Swamy MA, Sahgal P, Saxena S, Tiwari S, Mathur A, Nair MP (2009) Structural and antigenic variance between novel influenza A/H1N1/2009 and influenza A/H1N1/2008 viruses. J Infect Dev Ctries 4:001-006. doi: 10.3855/jidc.546
Section
Emerging Problems in Infectious Diseases