Diverse antibody genetic and recognition properties revealed following HIV-1 envelope glycoprotein immunization

J Immunol. 2015 Jun 15;194(12):5903-14. doi: 10.4049/jimmunol.1500122. Epub 2015 May 11.

Abstract

Isolation of mAbs elicited by vaccination provides opportunities to define the development of effective immunity. Ab responses elicited by current HIV-1 envelope glycoprotein (Env) immunogens display narrow neutralizing activity with limited capacity to block infection by tier 2 viruses. Intense work in the field suggests that improved Env immunogens are forthcoming, and it is therefore important to concurrently develop approaches to investigate the quality of vaccine-elicited responses at a higher level of resolution. In this study, we cloned a representative set of mAbs elicited by a model Env immunogen in rhesus macaques and comprehensively characterized their genetic and functional properties. The mAbs were genetically diverse, even within groups of Abs targeting the same subregion of Env, consistent with a highly polyclonal response. mAbs directed against two subdeterminants of Env, the CD4 binding site and V region 3, could in part account for the neutralizing activity observed in the plasma of the animal from which they were cloned, demonstrating the power of mAb isolation for a detailed understanding of the elicited response. Finally, through comparative analyses of mAb binding and neutralizing capacity of HIV-1 using matched Envs, we demonstrate complex relationships between epitope recognition and accessibility, highlighting the protective quaternary packing of the HIV-1 spike relative to vaccine-induced mAbs.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS Vaccines / immunology*
  • Amino Acid Sequence
  • Animals
  • Antibodies, Monoclonal / immunology
  • Antibodies, Neutralizing
  • Antibody Diversity / genetics*
  • Antibody Diversity / immunology*
  • Binding Sites, Antibody / genetics
  • CD4 Antigens / metabolism
  • Epitopes / immunology
  • HIV Antibodies / chemistry
  • HIV Antibodies / genetics*
  • HIV Antibodies / immunology*
  • HIV Envelope Protein gp120 / chemistry
  • HIV Envelope Protein gp120 / genetics
  • HIV-1 / immunology*
  • Immunization
  • Macaca mulatta
  • Molecular Sequence Data
  • Neutralization Tests
  • Peptide Fragments / chemistry
  • Peptide Fragments / genetics
  • Protein Binding
  • Protein Interaction Domains and Motifs
  • Recombinant Proteins / immunology
  • env Gene Products, Human Immunodeficiency Virus / immunology*

Substances

  • AIDS Vaccines
  • Antibodies, Monoclonal
  • Antibodies, Neutralizing
  • CD4 Antigens
  • Epitopes
  • HIV Antibodies
  • HIV Envelope Protein gp120
  • HIV envelope protein gp120 (305-321)
  • Peptide Fragments
  • Recombinant Proteins
  • env Gene Products, Human Immunodeficiency Virus