Generation of Monoclonal Antibodies against Dengue Virus Type 4 and Identification of Enhancing Epitopes on Envelope Protein

PLoS One. 2015 Aug 26;10(8):e0136328. doi: 10.1371/journal.pone.0136328. eCollection 2015.

Abstract

The four serotypes of dengue virus (DENV1-4) pose a serious threat to global health. Cross-reactive and non-neutralizing antibodies enhance viral infection, thereby exacerbating the disease via antibody-dependent enhancement (ADE). Studying the epitopes targeted by these enhancing antibodies would improve the immune responses against DENV infection. In order to investigate the roles of antibodies in the pathogenesis of dengue, we generated a panel of 16 new monoclonal antibodies (mAbs) against DENV4. Using plaque reduction neutralization test (PRNT), we examined the neutralizing activity of these mAbs. Furthermore, we used the in vitro and in vivo ADE assay to evaluate the enhancement of DENV infection by mAbs. The results indicate that the cross-reactive and poorly neutralizing mAbs, DD11-4 and DD18-5, strongly enhance DENV1-4 infection of K562 cells and increase mortality in AG129 mice. The epitope residues of these enhancing mAbs were identified using virus-like particle (VLP) mutants. W212 and E26 are the epitope residues of DD11-4 and DD18-5, respectively. In conclusion, we generated and characterized 16 new mAbs against DENV4. DD11-4 and D18-5 possessed non-neutralizing activities and enhanced viral infection. Moreover, we identified the epitope residues of enhancing mAbs on envelope protein. These results may provide useful information for development of safe dengue vaccine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Blocking / immunology
  • Antibodies, Monoclonal / immunology*
  • Antibodies, Neutralizing / immunology*
  • Antibodies, Viral / immunology
  • Antibody-Dependent Enhancement / immunology*
  • Blotting, Western
  • Dengue / immunology*
  • Dengue / virology
  • Dengue Virus / immunology*
  • Epitope Mapping
  • Epitopes / immunology*
  • Female
  • Fluorescent Antibody Technique
  • Immunoenzyme Techniques
  • Mice
  • Mice, Inbred BALB C
  • Neutralization Tests
  • Viral Envelope Proteins / immunology*

Substances

  • Antibodies, Blocking
  • Antibodies, Monoclonal
  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Epitopes
  • Viral Envelope Proteins

Grants and funding

This funding was supported by grants from Academia Sinica, Ministry of Science and Technology (104-0210-01-09-02) and the National Science Council (NSC102-2325-B-001-010), Taiwan (to H-C Wu). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.