NK cell function and antibodies mediating ADCC in HIV-1-infected viremic and controller patients

Viral Immunol. 2011 Oct;24(5):359-68. doi: 10.1089/vim.2011.0025. Epub 2011 Sep 29.

Abstract

Natural killer (NK) cells have been suggested to play a protective role in HIV disease progression. One potent effector mechanism of NK cells is antibody-dependent cellular cytotoxicity (ADCC) mediated by antiviral antibodies binding to the FcγRIIIa receptor (CD16) on NK cells. We investigated NK cell-mediated ADCC function and the presence of ADCC antibodies in plasma from 20 HIV-1-infected patients and 10 healthy donors. The HIV-positive patients were divided into two groups: six who controlled viremia for at least 8 y without treatment (controllers), and 14 who were persistently viremic and not currently on treatment. Plasma from both patient groups induced NK cell IFN-γ expression and degranulation in response to HIV-1 envelope (Env) gp140-protein-coated cells. Patient antibodies mediating ADCC were largely directed towards the Env V3 loop, as identified by a gp140 protein lacking the V3 loop. Interestingly, in two controllers ADCC-mediating antibodies were more broadly directed to other parts of Env. A high viral load in patients correlated with decreased ADCC-mediated cytolysis of gp140-protein-coated target cells. NK cells from both infected patients and healthy donors degranulated efficiently in the presence of antibody-coated HIV-1-infected Jurkat cells. In conclusion, the character of ADCC-mediating antibodies differed in some controllers compared to viremic patients. NK cell ADCC activity is not compromised in HIV-infected patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antibodies, Monoclonal / immunology
  • Antibody-Dependent Cell Cytotoxicity / immunology*
  • Female
  • HIV Antibodies / blood
  • HIV Antibodies / immunology*
  • HIV Envelope Protein gp120 / immunology
  • HIV Infections / immunology*
  • HIV Infections / virology
  • HIV-1 / immunology
  • HIV-1 / physiology
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology
  • Killer Cells, Natural / immunology*
  • Male
  • Middle Aged
  • Peptide Fragments / immunology
  • Viral Load
  • Viremia / immunology*
  • Viremia / virology
  • env Gene Products, Human Immunodeficiency Virus / immunology

Substances

  • Antibodies, Monoclonal
  • HIV Antibodies
  • HIV Envelope Protein gp120
  • HIV envelope protein gp120 (305-321)
  • Immunoglobulin G
  • Peptide Fragments
  • env Gene Products, Human Immunodeficiency Virus
  • gp140 envelope protein, Human immunodeficiency virus 1