Plant-produced anti-dengue virus monoclonal antibodies exhibit reduced antibody-dependent enhancement of infection activity

J Gen Virol. 2016 Dec;97(12):3280-3290. doi: 10.1099/jgv.0.000635. Epub 2016 Oct 20.

Abstract

The mAb E60 has the potential to be a desirable therapeutic molecule since it efficiently neutralizes all four serotypes of dengue virus (DENV). However, mammalian-cell-produced E60 exhibits antibody-dependent enhancement of infection (ADE) activity, rendering it inefficacious in vivo, and treated animals more susceptible to developing more severe diseases during secondary infection. In this study, we evaluated a plant-based expression system for the production of therapeutically suitable E60. The mAb was transiently expressed in Nicotiana benthamianaWT and a ∆XFT line, a glycosylation mutant lacking plant-specific N-glycan residues. The mAb was efficiently expressed and assembled in leaves and exhibited highly homogenous N-glycosylation profiles, i.e. GnGnXF3 or GnGn structures, depending on the expression host. Both E60 glycovariants demonstrated equivalent antigen-binding specificity and in vitro neutralization potency against DENV serotypes 2 and 4 compared with their mammalian-cell-produced counterpart. By contrast, plant-produced E60 exhibited reduced ADE activity in Fc gamma receptor expressing human cells. Our results suggest the ability of plant-produced antibodies to minimize ADE, which may lead to the development of safe and highly efficacious antibody-based therapeutics against DENV and other ADE-prone viral diseases. Our study provides so far unknown insight into the relationship between mAb N-glycosylation and ADE, which contributes to our understanding of how sugar moieties of antibodies modulate Fc-mediated functions and viral pathogenesis.

MeSH terms

  • Antibodies, Monoclonal / genetics*
  • Antibodies, Monoclonal / immunology*
  • Antibodies, Neutralizing / genetics
  • Antibodies, Neutralizing / immunology
  • Antibodies, Viral / genetics*
  • Antibodies, Viral / immunology*
  • Antibody-Dependent Enhancement / immunology*
  • Dengue / immunology*
  • Dengue / virology
  • Dengue Virus / genetics
  • Dengue Virus / immunology*
  • Gene Expression
  • Humans
  • Nicotiana / genetics*
  • Nicotiana / metabolism

Substances

  • Antibodies, Monoclonal
  • Antibodies, Neutralizing
  • Antibodies, Viral