mDCs and pDCs from PHIV subjects stimulate allogeneic CD4⁺ and CD8⁺ T cells. mDCs and pDCs purified from HIV-seronegative subjects or people with primary HIV infection were cultured with PBMCs depleted of antigen-presenting cells from uninfected subjects. Proliferation was evaluated at day 5 by measurement of ³H-thymidine incorporation and was expressed as a SI. The SI was determined by dividing the proliferation induced in the presence of DCs by the proliferation observed in a culture with no DCs added. The mean T-cell proliferation induced by (A) mDCs and (B) pDCs is shown from uninfected subjects (N = 5, □) and subjects at Fiebig stages I-II (N = 1,), III-IV (N = 2, ■), and V-VI (N = 9,▧). The panels below show the correlation of (C-E) mDC-induced and (D-F) pDC-induced T-cell proliferation to (C-D) CD4 counts and (E-F) plasma viral load in all the HIV-infected subjects at Fiebig stages I-VI. Statistical analysis was performed using a Spearman correlation.