In untreated HIV-1-infected children, PBMC-associated HIV DNA levels and cell-free HIV RNA levels are correlated to distinct T-lymphocyte populations.

Background: Clinical studies support biologically independent roles of cell-free HIV particles and HIV-infected cells in disease progression. The associations between the level of infected cells and immune markers have been poorly studied, particularly in perinatally infected children.

Objective: We tested the hypothesis that independent roles of cell-free virus and infected cells in HIV pathogenesis should be revealed by different associations between each of them and specific immune markers.

Methods: Levels of HIV RNA and DNA, HIV-specific CD8 T lymphocytes, activated and naive/memory T lymphocytes were determined in 44 untreated HIV-1-infected children. Pearson partial correlation coefficients were used to assess associations between the variables.

Results: Here we provide new information, by showing a direct correlation between the percentages of CD4HLA-DR lymphocytes and HIV DNA levels. Furthermore, higher HIV-specific CD8 T-lymphocyte frequencies were associated with lower HIV DNA levels. In contrast, CD838 lymphocytes and memory CD4 lymphocytes were correlated only to the HIV RNA level. All correlations were independent of age and CD4 depletion.

Conclusions: Several immune markers were correlated to either the HIV RNA or the HIV DNA level, but never to both of them, supporting the concept that cell-free virus and infected cells play different roles in HIV-1 immunopathogenesis.