• Study on epitope mapping and in vitro evaluation of immunogenic and immunomodulatory properties of antigenic region 4 of HA protein of H1N1 virus
  • Niloufar hajibeigy,1 Ardeshir Hesampour,2,*
    1. Islamic Azad University Central Tehran Branch, Biology Department
    2. Islamic Azad University Central Tehran Branch, Biology Department


  • Introduction: Influenza virus, which causes very important respiratory disease, belongs to the Orthomyxo viridae family. The most numerous proteins on the influenza virus envelope are HA proteins, which have cleaved by cellular protease into HA1 and HA2 .The first 11 residues and fusion peptide in HA2 are conserved between all influenza virus subtypes.
  • Methods: The similarity between HA protein sequence and other sequences done by online NCBI Blast service and the phylogenetic tree was drawn by phylogeny online tools. The amino acid sequence was analyzed for B and T cell’s epitopes prediction. The prediction was done by using Immune Epitopes Data Base (IEDB) online tools (http://www.iedb.org/). The 3D structure prediction also is done by Phyre2 (http://www.sbg.bio.ic.ac.uk/phyre2/html/) and Swiss model (https://swissmodel.expasy.org/) online tools. The quality of the 3D model, c-score and RMSD calculated by I-TASSER online tools (https://zhanglab.ccmb.med.umich.edu).
  • Results: The 3D model structure of the proposed protein conforms to the compatibility with the lowest energy. The result of immunogenicity, Emini surface accessibility, Kolaskar-Tongaonkar antigenicity and Parker hydrophilicity prove that the HA protein can stimulate the immune system. Hence, using in-silico methods can save time and reduce costs. Phylogenetic analysis of it, showed that the strain isolated from Iran have many similarities as compared with the strain isolated from the countries that mentioned in figures and the basis of done predictions, production of a protective vaccine against each of these strains can be effective against the other one.
  • Conclusion: Identification of antibodies against conserved epitopes of HA is an important step toward development of influenza vaccine; hence, HA protein prepared in this study could be an appropriate subunit vaccine candidate for preventing influenza virus infection.
  • Keywords: H1N1 , BIOINFORMATIC, HA protein, epitopes, modeling