title: Identification of a linear epitope on the haemagglutinin protein of pandemic A/H1N1 2009 influenza virus using monoclonal antibodies.
abstract: A novel influenza A/H1N1 virus, emerging from Mexico and the United States in the spring of 2009, caused the pandemic human infection of 2009-2010. The haemagglutinin (HA) glycoprotein is the major surface antigen of influenza A virus and plays an important role in viral infection. In this study, three hybridoma cell lines secreting specific monoclonal antibodies (Mabs) against the HA protein of pandemic influenza A/H1N1 2009 virus were generated with the recombinant plasmid pCAGGS-HA as an immunogen. Using Pepscan analysis, the binding sites of these Mabs were identified in a linear region of the HA protein. Further, refined mapping was conducted using truncated peptides expressed as GST-fusion proteins in E. coli. We found that the (250)VPRYA(254) motif was the minimal determinant of the linear epitope that could be recognized by the Mabs. Alignment with sequences from the databases showed that the amino acid residues of this epitope were highly conserved among all pandemic A/H1N1 2009 viruses as well as the classical swine H1N1 viruses isolated to date. These results provide additional insights into the antigenic structure of the HA protein and virus-antibody interactions at the amino acid level, which may assist in the development of specific diagnostic methods for influenza viruses.
authors.affiliation: Animal Influenza Laboratory of the Ministry of Agriculture, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 427 Maduan Street, Harbin, 150001, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Chuanling
authors.initials: C
authors.lastname: Qiao
authors.forename: Jingfei
authors.initials: J
authors.lastname: Wang
authors.forename: Huanliang
authors.initials: H
authors.lastname: Yang
authors.forename: Hualan
authors.initials: H
authors.lastname: Chen
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology* / Q000302:isolation & purification; D000914:Antibodies, Viral / Q000276:immunology* / Q000302:isolation & purification; D018604:Epitope Mapping; D000939:Epitopes / Q000276:immunology*; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000276:immunology*; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology* / Q000302:isolation & purification; D007251:Influenza, Human / Q000821:virology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D000939:Epitopes; D019267:Hemagglutinin Glycoproteins, Influenza Virus