IFN-α intracellular labeling. Histograms represent IFN-α⁺ cells among total spleen mononuclear cells (all), CD123⁺BDCA4⁺ cells (pDCs), HLA-DR⁺CD19⁻CD11c⁺ cells (mDCs), CD19⁺ B cells, or CD3⁺ T cells. Data are from HIV⁺ patient M and from HIV⁻ patient A, except for CD3 labeling, which is from patient L. This figure is representative of 4 HIV⁺ patients who were positive for IFN-α in situ and 3 HIV⁻ patients who were negative for IFN-α in situ.