Antibody-DEPENDENT, FcγRI-mediated neutralization of HIV-1 in TZM-bl cells occurs independently of phagocytosis

J Virol. 2013 May;87(9):5287-90. doi: 10.1128/JVI.00278-13. Epub 2013 Feb 13.

Abstract

We previously showed that expression of human FcγRI on TZM-bl cells potentiates neutralization by gp41 membrane-proximal external region (MPER)-specific antibodies. Here we show that lysosomotropic reagents known to block phagocytosis do not diminish this effect. We also show that FcγRI occasionally potentiates neutralization by antibodies against the V3 loop of gp120 and cluster I of gp41. We conclude that FcγRI provides a kinetic advantage for neutralizing antibodies against partially cryptic epitopes independent of phagocytosis.

Publication types

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

MeSH terms

  • Antibodies, Neutralizing / immunology*
  • Cell Line
  • HIV Antibodies / immunology*
  • HIV Envelope Protein gp120 / immunology
  • HIV Infections / immunology*
  • HIV Infections / virology
  • HIV-1 / immunology*
  • Humans
  • Neutralization Tests
  • Phagocytosis*
  • Receptors, IgG / genetics
  • Receptors, IgG / immunology*

Substances

  • Antibodies, Neutralizing
  • HIV Antibodies
  • HIV Envelope Protein gp120
  • Receptors, IgG