IFNα/βR expression is diminished on monocytes of HIV-1–infected persons. Individual flow cytometry histograms show IFNα/βR expression (solid curve) with isotype control (dashed line) on CD14-gated monocytes from uninfected (A) and HIV-1–infected (B) persons. IFNα/βR expression was significantly diminished on CD14⁺ monocytes of HIV-1–infected persons compared with uninfected persons (P < .001; C). IFNα/βR expression was also diminished on CD11c⁺ mDCs and CD11c⁻ pDCs of HIV-1–infected persons compared with uninfected subjects (P = .052 and P = .046, respectively; D). DCs were defined according to the expression of CD11 on the gated HLA-DR bright, Lin1⁻ population (see “Methods”). HIV-1 infection was not associated with significant reductions in IFNα/βR expression on CD3⁺/CD4⁺ or CD3⁺/CD8⁺ T cells (P = .584 and P = .321, respectively; E) Horizontal bars in panels C through E represent median values.