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’s 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 CD4+HLA-DR+ lymphocytes and HIV DNA levels. Furthermore, higher HIV-specific CD8 T lymphocyte frequencies were associated with lower HIV DNA levels. In contrast, CD8+38+ lymphocytes and memory CD4 lymphocytes were correlated only to the HIV RNA level. All correlations were independent of age and CD4 depletion. Conclusion: 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.