Initiation of Antiretroviral Therapy (ART) at Different Stages of HIV-1 Disease Is Not Associated with the Proportion of Exhausted CD8+ T Cells

PLoS One. 2015 Oct 1;10(10):e0139573. doi: 10.1371/journal.pone.0139573. eCollection 2015.

Abstract

CD8+ T cell-restricted immunity is important in the control of HIV-1 infection, but continued immune activation results in CD8+ T cell dysfunction. Early initiation of antiretroviral treatment (ART) and the duration of ART have been associated with immune reconstitution. Here, we evaluated whether restoration of CD8+ T cell function in HIV-1-infected individuals was dependent on early initiation of ART. HIV-specific CD107a, IFNγ, IL-2, TNFα and MIP-1β expression by CD8+ T cells and the frequency of CD8+ T cells expressing PD-1, 2B4 and CD160 were measured by flow cytometry. The frequency of CD8+ T cells expressing the inhibitory markers PD-1, 2B4 and CD160 was lower in ART-treated individuals compared with ART-naïve individuals and similar to the frequency in HIV-uninfected controls. The expression of the three markers was similarly independent of when therapy was initiated. Individuals treated before seroconversion displayed an HIV-specific CD8+ T cell response that included all five functional markers; this was not observed in individuals treated after seroconversion or in ART-naïve individuals. In summary, ART appears to restore the total CD8+ T cell population to a less exhausted phenotype, independent of the time point of initiation. However, to preserve multifunctional, HIV-1-specific CD8+ T cells, ART might have to be initiated before seroconversion.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Anti-HIV Agents / therapeutic use*
  • Antiretroviral Therapy, Highly Active*
  • CD8-Positive T-Lymphocytes / immunology*
  • Case-Control Studies
  • Female
  • HIV Infections / drug therapy
  • HIV Infections / immunology*
  • HIV Infections / virology
  • HIV-1 / drug effects
  • HIV-1 / immunology*
  • Humans
  • Male
  • Middle Aged
  • Viral Load / immunology*

Substances

  • Anti-HIV Agents

Grants and funding

This work was supported by the Danish AIDS foundation and scholarship support from the Region of Southern Denmark (SSJ). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.