Further Evidence That the Expression of CD38 and HLA-DR+ in CD8+ Lymphocytes Does Not Correlate to Disease Progression in HIV-1 Vertically Infected Children

Abstract

Background: In adults, an increase in CD8+CD38+ T cell levels is a strong indicator of disease progression in HIV infection. However, in children, data are conflicting. Slow-progressing children (SPC) provide an exceptional resource for the investigation and clarification of the immunological and virological mechanisms of natural control of HIV infection and can be used to investigate prognostic indicators of disease progression. Objectives: To investigate the immune activation status and T regulatory (Treg) cell levels in SPC. Study design: A cross-sectional study was carried out on 28 children 8 years old and older who were vertically infected with HIV. The children were stratified into 3 groups according to their clinical outcome: SPC (anti-retroviral-therapy-naïve; ≥8 years-old; CD4 ≥20%; viral load <25,000 copies), IF/VF (anti-retroviral-therapy but with no therapeutic response), and IS/VS (anti-retroviral therapy with good therapeutic response). Uninfected children (NI) were assessed as healthy control group. Results: A higher percentage of activated CD8+ T cells were found in all HIV infected children, regardless of the evolution of disease. The activation of CD8+ T cells was not associated with either viral load or the percentage of CD4+ T cells. In addition, Treg cell levels did not show any correlation with the clinical outcome or the activation status of CD8+ T cells. Conclusions: HIV-1-infected children presented an increased percentage of activated CD8+ T cells and an unaltered percentage of Treg cells, regardless of their clinical evolution. Thus, these immunological parameters should not be used for prognostic evaluation.