Nonpathogenic SIV infection of African green monkeys induces a strong but rapidly controlled type I IFN response

J Clin Invest. 2009 Dec;119(12):3544-55. doi: 10.1172/JCI40093.

Abstract

African green monkeys (AGMs) infected with the AGM type of SIV (SIVagm) do not develop chronic immune activation and AIDS, despite viral loads similar to those detected in humans infected with HIV-1 and rhesus macaques (RMs) infected with the RM type of SIV (SIVmac). Because chronic immune activation drives progressive CD4+ T cell depletion and immune cell dysfunctions, factors that characterize disease progression, we sought to understand the molecular basis of this AGM phenotype. To this end, we longitudinally assessed the gene expression profiles of blood- and lymph node-derived CD4+ cells from AGMs and RMs in response to SIVagm and SIVmac infection, respectively, using a genomic microarray platform. The molecular signature of acute infection was characterized, in both species, by strong upregulation of type I IFN-stimulated genes (ISGs). ISG expression returned to basal levels after postinfection day 28 in AGMs but was sustained in RMs, especially in the lymph node-derived cells. We also found that SIVagm induced IFN-alpha production by AGM cells in vitro and that low IFN-alpha levels were sufficient to induce strong ISG responses. In conclusion, SIV infection triggered a rapid and strong IFN-alpha response in vivo in both AGMs and RMs, with this response being efficiently controlled only in AGMs, possibly as a result of active regulatory mechanisms.

Publication types

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

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes / immunology
  • Chlorocebus aethiops
  • Gene Expression Profiling
  • HIV Infections / immunology
  • HIV Infections / virology
  • HIV-1
  • Host-Pathogen Interactions / genetics
  • Host-Pathogen Interactions / immunology
  • Humans
  • Interferon Type I / biosynthesis*
  • Interferon Type I / genetics
  • Interferon-alpha / biosynthesis
  • Interferon-alpha / genetics
  • Macaca mulatta
  • Oligonucleotide Array Sequence Analysis
  • Simian Acquired Immunodeficiency Syndrome / genetics
  • Simian Acquired Immunodeficiency Syndrome / immunology*
  • Simian Acquired Immunodeficiency Syndrome / virology
  • Simian Immunodeficiency Virus / genetics
  • Simian Immunodeficiency Virus / immunology*
  • Simian Immunodeficiency Virus / pathogenicity*
  • Simian Immunodeficiency Virus / physiology
  • Species Specificity
  • Virulence / immunology
  • Virus Replication

Substances

  • Interferon Type I
  • Interferon-alpha