Presence of suppressor HIV-specific CD8+ T cells is associated with increased PD-1 expression on effector CD8+ T cells

J Immunol. 2008 Jun 1;180(11):7757-63. doi: 10.4049/jimmunol.180.11.7757.

Abstract

Mechanisms leading to the observed immune dysregulation in HIV-1 infection are not well understood. HIV-specific IL-10-positive CD8(+) T cells are increased in advanced HIV disease. We have previously reported that Gag-specific IL-10-positive CD8(+) T cells suppressed cytolysis. In this study we describe the suppressive effect of Nef-specific IL-10-positive CD8(+) T cells. Interestingly, simultaneous removal of both Gag- and Nef-specific IL-10-positive CD8(+) T cells led to higher HIV-specific cytolysis compared with the removal of Nef-specific IL-10-positive CD8(+) T cells alone. We also examined the level of programmed cell death-1 (PD-1) as a measure of immune dysfunction in association with IL-10-positive suppressor CD8(+) T cells. The level of PD-1 expression on CD107-positive effector CD8(+) T cells was significantly increased when IL-10-positive suppressor CD8(+) T cells were present (p < 0.05). Our results suggest that IL-10-positive suppressor CD8(+) T cells contribute to the immune dysfunction observed in advanced HIV infection and that the concomitant presence of multiple IL-10-positive CD8(+) T cell populations may have an additive suppressive effect.

Publication types

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

MeSH terms

  • Adult
  • Antigens, CD / immunology
  • Antigens, CD / metabolism*
  • Apoptosis Regulatory Proteins / immunology
  • Apoptosis Regulatory Proteins / metabolism*
  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / metabolism
  • Cytotoxicity, Immunologic
  • HIV / immunology*
  • HIV Infections / immunology*
  • HIV Infections / virology
  • Humans
  • Interleukin-10 / immunology
  • Interleukin-10 / metabolism
  • Middle Aged
  • Programmed Cell Death 1 Receptor
  • T-Lymphocyte Subsets / immunology*
  • T-Lymphocyte Subsets / metabolism
  • Transforming Growth Factor beta / immunology
  • Transforming Growth Factor beta / metabolism
  • gag Gene Products, Human Immunodeficiency Virus / immunology*
  • nef Gene Products, Human Immunodeficiency Virus / immunology*

Substances

  • Antigens, CD
  • Apoptosis Regulatory Proteins
  • PDCD1 protein, human
  • Programmed Cell Death 1 Receptor
  • Transforming Growth Factor beta
  • gag Gene Products, Human Immunodeficiency Virus
  • nef Gene Products, Human Immunodeficiency Virus
  • Interleukin-10