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Identification of a Highly Conserved H1 Subtype-Specific Epitope with Diagnostic Potential in the Hemagglutinin Protein of Influenza A Virus

By Rongmao Zhao, Shujuan Cui, Li Guo, Chao Wu, Richard Gonzalez, Gláucia Paranhos-Baccalà, Guy Vernet, Jianwei Wang and Tao Hung


Subtype specificity of influenza A virus (IAV) is determined by its two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). For HA, 16 distinct subtypes (H1–H16) exist, while nine exist for NA. The epidemic strains of H1N1 IAV change frequently and cause annual seasonal epidemics as well as occasional pandemics, such as the notorious 1918 influenza pandemic. The recent introduction of pandemic A/H1N1 IAV (H1N1pdm virus) into humans re-emphasizes the public health concern about H1N1 IAV. Several studies have identified conserved epitopes within specific HA subtypes that can be used for diagnostics. However, immune specific epitopes in H1N1 IAV have not been completely assessed. In this study, linear epitopes on the H1N1pdm viral HA protein were identified by peptide scanning using libraries of overlapping peptides against convalescent sera from H1N1pdm patients. One epitope, P5 (aa 58–72) was found to be immunodominant in patients and to evoke high titer antibodies in mice. Multiple sequence alignments and in silico coverage analysis showed that this epitope is highly conserved in influenza H1 HA [with a coverage of 91.6% (9,860/10,767)] and almost completely absent in other subtypes [with a coverage of 3.3% (792/23,895)]. This previously unidentified linear epitope is located outside the five well-recognized antigenic sites in HA. A peptide ELISA method based on this epitope was developed and showed high correlation (χ2 = 51.81, P<0.01, Pearson correlation coefficient R = 0.741) with a hemagglutination inhibition test. The highly conserved H1 subtype-specific immunodominant epitope may form the basis for developing novel assays for sero-diagnosis and active surveillance against H1N1 IAVs

Topics: Research Article
Publisher: Public Library of Science
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Provided by: PubMed Central

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  22. (1988). Genetic control and fine specificity of the immune response to a synthetic peptide of influenza virus hemagglutinin.
  23. (2005). Identification of immunodominant epitopes on the membrane protein of the severe acute respiratory syndrome-associated coronavirus.
  24. (2010). Influenza vaccines for the future.
  25. (2005). Influenza: lessons from past pandemics, warnings from current incidents.
  26. (2004). Influenza: old and new threats.
  27. (2002). Klimov A
  28. (2010). Manual of Diagnostic Tests and Vaccines for Terrestrial Animals.
  29. (1988). Minimum requirements for immunogenic and antigenic activities of homologs of a synthetic peptide of influenza virus hemagglutinin.
  30. (2009). Monoclonal antibodies against the fusion peptide of hemagglutinin protect mice from lethal influenza A virus H5N1 infection.
  31. (2009). One step closer to universal influenza epitopes.
  32. (2010). Organization website. Available: publications/influenza/en/whocdscsrncs20025rev.pdf. Accessed
  33. (2008). Predicting flexible length linear B-cell epitopes.
  34. (2001). Production of antipeptide antisera.
  35. (2011). Prokaryotic expression and purification of HA1 and HA2 polypeptides for serological analysis of the 2009 pandemic H1N1 influenza virus.
  36. (2006). Quantifying influenza vaccine efficacy and antigenic distance.
  37. (2000). Receptor binding and membrane fusion in virus entry: the influenza hemagglutinin.
  38. (2006). Role of the laboratory in diagnosis of influenza during seasonal epidemics and potential pandemics.
  39. (2011). Screening of Random Peptide Library of Hemagglutinin from Pandemic
  40. (2007). Sette A
  41. (2009). Structural and functional bases for broad-spectrum neutralization of avian and human influenza A viruses.
  42. (1981). Structural identification of the antibodybinding sites of Hong Kong influenza haemagglutinin and their involvement in antigenic variation.
  43. (1981). Structure of the haemagglutinin membrane glycoprotein of influenza virus at 3 A resolution.
  44. (2010). The
  45. (1982). The antigenic structure of the influenza virus A/PR/8/34 hemagglutinin (H1 subtype).
  46. (2005). The origins of pandemic influenza–lessons from the 1918 virus.
  47. (1987). The structure and function of the hemagglutinin membrane glycoprotein of influenza virus.
  48. (2009). The who, how and where of antigen presentation to B cells.
  49. (2003). Understanding sensitivity and specificity with the right side of the brain.
  50. (2008). Universal antibodies and their applications to the quantitative determination of virtually all subtypes of the influenza A viral hemagglutinins.
  51. (2010). Utility of pandemic H1N1

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