Flow cytometric analysis of intracellular TNFα production by myeloid dendritic cells and monocytes from patients and controls. Upper panels show gating of peripheral blood mononuclear cells (PBMCs) from representative patients with discoid lupus erythematosus (DLE), dermatomyositis (DM) or controls stained with fluorochrome-conjugated appropriate antibodies (A) myeloid dendritic cells (lineage negative, HLADR+, CD11c+) or (B) monocytes (CD64+CD14+). Lower panels show intracellular expression of TNFα in (A) myeloid dendritic cells or (B) monocytes. The numbers in the upper panels state the percentage of cell subset per total population of PBMCs. The numbers in the lower panels state the percentage of myeloid dendritic cells or monocytes producing TNFα.