Dendritic cells are less susceptible to human immunodeficiency virus type 2 (HIV-2) infection than to HIV-1 infection

J Virol. 2007 Dec;81(24):13486-98. doi: 10.1128/JVI.00976-07. Epub 2007 Oct 3.

Abstract

Human immunodeficiency virus type 1 (HIV-1) infection of dendritic cells (DCs) has been documented in vivo and may be an important contributor to HIV-1 transmission and pathogenesis. HIV-1-specific CD4(+) T cells respond to HIV antigens presented by HIV-1-infected DCs and in this process become infected, thereby providing a mechanism through which HIV-1-specific CD4(+) T cells could become preferentially infected in vivo. HIV-2 disease is attenuated with respect to HIV-1 disease, and host immune responses are thought to be contributory. Here we investigated the susceptibility of primary myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) to infection by HIV-2. We found that neither CCR5-tropic primary HIV-2 isolates nor a lab-adapted CXCR4-tropic HIV-2 strain could efficiently infect mDCs or pDCs, though these viruses could infect primary CD4(+) T cells in vitro. HIV-2-exposed mDCs were also incapable of transferring virus to autologous CD4(+) T cells. Despite this, we found that HIV-2-specific CD4(+) T cells contained more viral DNA than memory CD4(+) T cells of other specificities in vivo. These data suggest that either infection of DCs is not an important contributor to infection of HIV-2-specific CD4(+) T cells in vivo or that infection of DCs by HIV-2 occurs at a level that is undetectable in vitro. The frequent carriage of HIV-2 DNA within HIV-2-specific CD4(+) T cells, however, does not appear to be incompatible with preserved numbers and functionality of HIV-2-specific CD4(+) T cells in vivo, suggesting that additional mechanisms contribute to maintenance of HIV-2-specific CD4(+) T-cell help in vivo.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Antigen Presentation
  • CD4 Lymphocyte Count
  • CD4-Positive T-Lymphocytes / virology
  • Cell Differentiation
  • Coculture Techniques
  • DNA, Viral / analysis
  • DNA, Viral / isolation & purification
  • Dendritic Cells / cytology
  • Dendritic Cells / immunology
  • Dendritic Cells / virology*
  • Flow Cytometry
  • HIV-1 / genetics
  • HIV-1 / isolation & purification
  • HIV-1 / pathogenicity*
  • HIV-1 / physiology
  • HIV-2 / genetics
  • HIV-2 / isolation & purification
  • HIV-2 / pathogenicity*
  • HIV-2 / physiology
  • Humans
  • Immunologic Memory
  • Lymphocyte Activation
  • Polymerase Chain Reaction

Substances

  • DNA, Viral