Detection of Circulating Asian H5N1 Viruses by a Newly Established Monoclonal Antibody

Biochem Biophys Res Commun. 2009 Jan 9;378(2):197-202. doi: 10.1016/j.bbrc.2008.11.022. Epub 2008 Nov 14.


Monoclonal antibodies (MAbs) against the recently emerged Asian H5N1 virus (A/crow/Kyoto/53/2004) were generated. From five anti-hemagglutinin (HA) MAbs, four antibodies (3C11, 4C12, 3H12, and 3H4) broadly in vitro recognized and neutralized H5 subtypes, including H5N1. By contrast, the 4G6 MAb specifically reacted with H5N1-HA and not with H5N2- or H5N3-HAs from previous epidemics. The 4G6 MAb was useful for immunofluorescence assays but not for immunoblotting, suggesting that this antibody recognizes a conformational epitope of the H5N1-HA protein. An intensive epitope-mapping analysis demonstrated that the 4G6 MAb recognizes Asp59, which is highly conserved among currently circulating H5N1 lineages. Further, a 4G6-based antigen capture enzyme-linked immunosorbent assay detected H5N1 even that derived from clade 2.2 (A/chicken/Egypt/CL-61/2007) from infected chicken lung before virus isolation. Taken together, these results suggest that the established MAbs, especially 4G6, are useful for rapid and specific detection of Asian H5N1 viruses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / immunology*
  • Antibodies, Viral / immunology*
  • Asia
  • Chickens / virology
  • Enzyme-Linked Immunosorbent Assay*
  • Epitope Mapping
  • Female
  • Hemagglutinin Glycoproteins, Influenza Virus / classification
  • Hemagglutinin Glycoproteins, Influenza Virus / immunology*
  • Influenza A Virus, H5N1 Subtype / immunology
  • Influenza A Virus, H5N1 Subtype / isolation & purification*
  • Influenza in Birds / diagnosis*
  • Influenza in Birds / immunology
  • Mice
  • Mice, Inbred BALB C
  • Neutralization Tests
  • Phylogeny


  • Antibodies, Monoclonal
  • Antibodies, Viral
  • Hemagglutinin Glycoproteins, Influenza Virus
  • hemagglutinin, avian influenza A virus