Initial antibodies binding to HIV-1 gp41 in acutely infected subjects are polyreactive and highly mutated

J Exp Med. 2011 Oct 24;208(11):2237-49. doi: 10.1084/jem.20110363. Epub 2011 Oct 10.

Abstract

The initial antibody response to HIV-1 is targeted to envelope (Env) gp41, and is nonneutralizing and ineffective in controlling viremia. To understand the origins and characteristics of gp41-binding antibodies produced shortly after HIV-1 transmission, we isolated and studied gp41-reactive plasma cells from subjects acutely infected with HIV-1. The frequencies of somatic mutations were relatively high in these gp41-reactive antibodies. Reverted unmutated ancestors of gp41-reactive antibodies derived from subjects acutely infected with HIV-1 frequently did not react with autologous HIV-1 Env; however, these antibodies were polyreactive and frequently bound to host or bacterial antigens. In one large clonal lineage of gp41-reactive antibodies, reactivity to HIV-1 Env was acquired only after somatic mutations. Polyreactive gp41-binding antibodies were also isolated from uninfected individuals. These data suggest that the majority of gp41-binding antibodies produced after acute HIV-1 infection are cross-reactive responses generated by stimulating memory B cells that have previously been activated by non-HIV-1 antigens.

Publication types

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

MeSH terms

  • Adult
  • Cell Lineage
  • Female
  • HIV Antibodies / classification
  • HIV Antibodies / genetics*
  • HIV Antibodies / immunology*
  • HIV Envelope Protein gp41 / immunology*
  • HIV-1 / immunology*
  • Humans
  • Male
  • Mutation*
  • Phylogeny
  • Plasma Cells / immunology
  • Plasma Cells / virology
  • Sequence Analysis, DNA
  • Viral Load
  • Viremia / immunology

Substances

  • HIV Antibodies
  • HIV Envelope Protein gp41