Efficient capture of antibody neutralized HIV-1 by cells expressing DC-SIGN and transfer to CD4+ T lymphocytes

J Immunol. 2007 Mar 1;178(5):3177-85. doi: 10.4049/jimmunol.178.5.3177.

Abstract

Infection of CD4+ T lymphocytes is enhanced by the capture and subsequent transfer of HIV-1 by dendritic cells (DCs) via the interaction with C-type lectins such as the DC-specific ICAM-grabbing nonintegrin (DC-SIGN). Numerous HIV-1 envelope-directed neutralizing Abs have been shown to successfully block the infection of CD4(+) T lymphocytes. In this study, we find that HIV-1-neutralized with the mAb 2F5 is more efficiently captured by immature monocyte-derived DCs (iMDDCs) and DC-SIGN-expressing Raji cells (Raji-DC-SIGN). Furthermore, a 2F5-neutralized virus captured by these cells was able to subsequently infect CD4+ T lymphocytes upon the release of HIV-1 from iMDDCs, thereby enhancing infection. We show that upon transfer via DC-SIGN-expressing cells, HIV-1 is released from immune-complexes with the Abs 2F5 and 4E10 (gp41-directed) and 2G12, 4.8D, and 1.7b (gp120-directed). The nonneutralizing V3-21 (V3 region of the gp120-directed) Ab enhanced HIV-1 infection upon capture and transfer via Raji-DC-SIGN cells, whereas no infection was observed with the neutralizing b12 Ab (gp120-directed), indicating that different Abs have variant effects on inhibiting HIV-1 transfer to CD4+ T lymphocytes. The increased capture of the 2F5-neutralized virus by iMDDCs was negated upon blocking the Fc receptors. Blocking DC-SIGN on iMDDCs resulted in a 70-75% inhibition of HIV-1 capture at 37 degrees C, whereas at 4 degrees C a full block was observed, showing that the observed transfer is mediated via DC-SIGN. Taken together, we propose that DC-SIGN-mediated capture of neutralized HIV-1 by iMDDCs has the potential to induce immune evasion from the neutralization effects of HIV-1 Abs, with implications for HIV-1 pathogenesis and vaccine development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS Vaccines / immunology
  • Antibodies, Monoclonal / immunology*
  • Antibodies, Monoclonal / pharmacology
  • CD4-Positive T-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / virology
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / immunology*
  • Cell Line
  • Gene Expression
  • HIV Antibodies / immunology*
  • HIV Antibodies / pharmacology
  • HIV Envelope Protein gp120 / immunology
  • HIV Infections / immunology
  • HIV Infections / transmission
  • HIV-1 / immunology*
  • HIV-1 / pathogenicity
  • Humans
  • Lectins, C-Type / genetics
  • Lectins, C-Type / immunology*
  • Monocytes / immunology*
  • Monocytes / virology
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / immunology*
  • Receptors, Fc / antagonists & inhibitors
  • Receptors, Fc / immunology

Substances

  • AIDS Vaccines
  • Antibodies, Monoclonal
  • Cell Adhesion Molecules
  • DC-specific ICAM-3 grabbing nonintegrin
  • HIV Antibodies
  • HIV Envelope Protein gp120
  • Lectins, C-Type
  • Receptors, Cell Surface
  • Receptors, Fc