Direct quantification of cell-associated HIV DNA in isolated rectal and blood memory CD4 T cells revealed their similar and low infection levels in long-term treated HIV-infected patients.

To evaluate the contribution of CD4 T cells from blood and gut compartments to the HIV-1 reservoir, we directly quantified cell-associated HIV DNA in isolated rectal (R-) and peripheral blood (PB-) memory CD4 T cells from 11 successfully long-term treated patients. Proportion of activated (CD25(+); CD69(+); and HLA-DR(+)) and CCR5 expressing CD4 T cells were markedly higher in rectal tissue compared with blood. However, HIV-1 infection levels of R- and PB-memory CD4 T cells did not significantly differ (medians: 4000 and 2100 copies per million cells) after effective long-term viral control, suggesting that each of these 2 compartments does not contribute in a similar fashion to the total HIV reservoir.