A New Glycan-Dependent CD4-Binding Site Neutralizing Antibody Exerts Pressure on HIV-1 In Vivo Academic Article uri icon

Overview

MeSH Major

  • Antibodies, Neutralizing
  • Antigens, CD4
  • HIV Antibodies
  • HIV-1
  • Polysaccharides

abstract

  • The CD4 binding site (CD4bs) on the envelope glycoprotein is a major site of vulnerability that is conserved among different HIV-1 isolates. Many broadly neutralizing antibodies (bNAbs) to the CD4bs belong to the VRC01 class, sharing highly restricted origins, recognition mechanisms and viral escape pathways. We sought to isolate new anti-CD4bs bNAbs with different origins and mechanisms of action. Using a gp120 2CC core as bait, we isolated antibodies encoded by IGVH3-21 and IGVL3-1 genes with long CDRH3s that depend on the presence of the N-linked glycan at position-276 for activity. This binding mode is similar to the previously identified antibody HJ16, however the new antibodies identified herein are more potent and broad. The most potent variant, 179NC75, had a geometric mean IC80 value of 0.42 μg/ml against 120 Tier-2 HIV-1 pseudoviruses in the TZM.bl assay. Although this group of CD4bs glycan-dependent antibodies can be broadly and potently neutralizing in vitro, their in vivo activity has not been tested to date. Here, we report that 179NC75 is highly active when administered to HIV-1-infected humanized mice, where it selects for escape variants that lack a glycan site at position-276. The same glycan was absent from the virus isolated from the 179NC75 donor, implying that the antibody also exerts selection pressure in humans.

publication date

  • January 2015

Research

keywords

  • Academic Article

Identity

Language

  • eng

PubMed Central ID

  • PMC4627763

Digital Object Identifier (DOI)

  • 10.1371/journal.ppat.1005238

PubMed ID

  • 26516768

Additional Document Info

start page

  • e1005238

volume

  • 11

number

  • 10