Characterization of an antigenic site that contains a dominant, type-specific neutralization determinant on the envelope protein domain III (ED3) of dengue 2 virus

Gregory D. Gromowski, Alan D.T. Barrett

Research output: Contribution to journalArticle

142 Scopus citations

Abstract

The surface of the mature dengue virus (DENV) particle consists of 90 envelope (E) protein dimers that mediate both receptor binding and fusion. The E protein ectodomain can be divided into three structural domains designated ED1, ED2, and ED3, of which ED3 contains the critical and dominant virus-specific neutralization sites. In this study the ED3 epitopes recognized by seven, murine, IgG1 DENV-2 type-specific, monoclonal antibodies (MAbs) were determined using site-directed mutagenesis of a recombinant DENV-2 ED3 (rED3) protein. A total of 41 single amino acid substitutions were introduced into the rED3 at 30 different surface accessible residues. The affinity of each MAb with the mutant rED3s was assessed by indirect ELISA and the results indicate that all seven MAbs recognize overlapping epitopes with residues K305 and P384 critical for binding. These residues are conserved among DENV-2 strains and cluster together on the upper lateral face of ED3. A linear relationship was observed between relative occupancy of ED3 on the virion by MAb and neutralization of the majority of virus infectivity (∼ 90%) for all seven MAbs. Depending on the MAb, it is predicted that between 10% and 50% relative occupancy of ED3 on the virion is necessary for virus neutralization and for all seven MAbs occupancy levels approaching saturation were required for 100% neutralization of virus infectivity. Overall, the conserved antigenic site recognized by all seven MAbs is likely to be a dominant DENV-2 type-specific, neutralization determinant.

Original languageEnglish (US)
Pages (from-to)349-360
Number of pages12
JournalVirology
Volume366
Issue number2
DOIs
StatePublished - Sep 30 2007

Keywords

  • Dengue
  • Envelope protein domain III
  • Flavivirus
  • Monoclonal antibodies
  • Neutralization

ASJC Scopus subject areas

  • Virology

Fingerprint Dive into the research topics of 'Characterization of an antigenic site that contains a dominant, type-specific neutralization determinant on the envelope protein domain III (ED3) of dengue 2 virus'. Together they form a unique fingerprint.

  • Cite this