Association of lymph-node antigens with lower Gag-specific central-memory and higher Env-specific effector-memory CD8(+) T-cell frequencies in a macaque AIDS model

Sci Rep. 2016 Jul 25:6:30153. doi: 10.1038/srep30153.

Abstract

Virus-specific CD8(+) T cells exert strong suppressive pressure on human/simian immunodeficiency virus (HIV/SIV) replication. These responses have been intensively examined in peripheral blood mononuclear cells (PBMCs) but not fully analyzed in lymph nodes (LNs), where interaction between CD8(+) T cells and HIV/SIV-infected cells occurs. Here, we investigated target antigen specificity of CD8(+) T cells in LNs in a macaque AIDS model. Analysis of virus antigen-specific CD8(+) T-cell responses in the inguinal LNs obtained from twenty rhesus macaques in the chronic phase of SIV infection showed an inverse correlation between viral loads and frequencies of CD8(+) T cells with CD28(+) CD95(+) central memory phenotype targeting the N-terminal half of SIV core antigen (Gag-N). In contrast, analysis of LNs but not PBMCs revealed a positive correlation between viral loads and frequencies of CD8(+) T cells with CD28(-)CD95(+) effector memory phenotype targeting the N-terminal half of SIV envelope (Env-N), soluble antigen. Indeed, LNs with detectable SIV capsid p27 antigen in the germinal center exhibited significantly lower Gag-N-specific CD28(+) CD95(+) CD8(+) T-cell and higher Env-N-specific CD28(-)CD95(+) CD8(+) T-cell responses than those without detectable p27. These results imply that core and envelope antigen-specific CD8(+) T cells show different patterns of interactions with HIV/SIV-infected cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acquired Immunodeficiency Syndrome / immunology*
  • Animals
  • Antigens, Viral / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Disease Models, Animal
  • Gene Products, env / immunology*
  • Germinal Center / immunology
  • Immunologic Memory / immunology*
  • Lymph Nodes / immunology*
  • Macaca / immunology*
  • Macaca mulatta / immunology
  • Simian Immunodeficiency Virus / immunology
  • Viral Load / immunology

Substances

  • Antigens, Viral
  • Gene Products, env