[T-cell subsets variation during clinical and immunological progression in vertically HIV-infected children]

We have investigated the relationship among peripheral blood T-cell subsets with immunological and clinical categories, and viral load (VL) in 65 HIV-1-infected children on stable antiretroviral therapy (ART): 26 (40%) children on combination therapy with 2 nucleoside inhibitors, and 39 (60%) children on highly active antiretroviral therapy (HAART). T-cell subsets were determined by flow cytometry. VL was quantified using a standardized molecular method. Naïve CD4+ T-cells (CD45RA+CD62L+) were lower in children with low %CD4+ T-cells, but neither in children with advanced stage of illness nor with high VL. By contrast, naïve CD8+ T-cells were lower in children with low %CD4+ T-cells, advanced stage of illness and high VL. Memory (CD45RO+) and activated (CD38+, HLA-DR+ and CD38+HLA-DR+) CD4+ and CD8+ T-cells were higher in children with low %CD4+ T-cells, advanced stage of illness and high VL. However, CD4+CD38+ T-cells were higher in HIV-children with CD4+ > 25% than in the control group (p < 0.001) and were diminished in children with low %CD4+ T-cells. Naïve and memory CD4+ and CD8+ T-cells are more tightly dependent on the immunological category than on clinical category or plasma VL. Furthermore, our data indicate an association between low %CD4+ T-cells, high VL and high expression of cellular activation markers, although not with advanced clinical stage, possibly due to ART.