Cytomegalovirus rather than HIV triggers the outgrowth of effector CD8+CD45RA+CD27- T cells in HIV-1-infected children

AIDS. 2005 Jul 1;19(10):1025-34. doi: 10.1097/01.aids.0000174448.25132.ad.

Abstract

Objective: To analyse the effect of viral coinfections on immune reconstitution in HIV-1-infected children (< 18 years) taking highly active antiretroviral therapy (HAART).

Methods: Absolute lymphocyte numbers of various subsets of CD8 T cells were measured.

Results: Prior cytomegalovirus (CMV) infection correlated with an increased number of CD8 effector T cells (i.e., CD45RA+CD27-) at baseline (CMV-seropositive versus CMV-seronegative patients; P = 0.009), as well as an increased state of T cell activation as defined by HLA-DR and CD38 expression. The expansion of effector CD8 T cells persisted over time, independent of the HIV response to HAART. Numbers of CD8 effector T cells were significantly higher in patients with CMV replication as reflected by persistent urinary CMV shedding and periodic CMV DNAaemia (P = 0.02). These patients also showed an increase in CMV-specific antibodies compared with those without CMV shedding (P = 0.007). The number of CMV-specific interferon-gamma (IFN-gamma)-producing CD8 T cells was lower in children who persistently shed CMV compared with those who did not (P = 0.02). In contrast, CMV-specific CD4 T cell responses were detected at similar levels in both groups.

Conclusions: In HIV-1-infected children, CMV infection correlated with the outgrowth of CD8+CD45RA+CD27- effector T cells. Activation of the immune system by persistent CMV secretion resulted in increasing CMV-specific IgG and higher numbers of CD8 effector T cells. Despite these increases, the CMV-specific IFN-gamma-producing CD8 T cell response was diminished, which could explain the inability to suppress CMV completely in 41% of HIV-1-infected children.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Antiretroviral Therapy, Highly Active
  • CD4-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / immunology
  • Child
  • Child, Preschool
  • Cytomegalovirus / immunology*
  • Cytomegalovirus Infections / immunology*
  • Female
  • HIV Infections / drug therapy
  • HIV Infections / immunology
  • HIV Infections / virology*
  • HIV-1 / immunology*
  • Humans
  • Infant
  • Leukocyte Common Antigens / immunology
  • Male
  • RNA, Viral / immunology
  • T-Lymphocytes / immunology*
  • Tumor Necrosis Factor Receptor Superfamily, Member 7 / immunology

Substances

  • RNA, Viral
  • Tumor Necrosis Factor Receptor Superfamily, Member 7
  • Leukocyte Common Antigens