Differential cytokine production in 2 subsets of pDCs. (A-D) After depletion of CD3⁺, CD19⁺, CD11b⁺, and DX5⁺ cells from BALB/c bone marrow, cells were stained with B220, CD11c, and 2E6 Abs. The 2E6⁺ (▪) or 2E6^– (▦) cells were sorted within the gate of B220⁺CD11c⁺ cells and then 4 × 10⁴ cells/well of each group were plated onto 96-well round-bottom plates. These cells were variously stimulated (influenza virus PR8, CpG-ODN, or HSV) at 37°C for 24 hours, then supernatants of IFN-α, TNF-α, IL-6, and IL-12p70 were measured by ELISA. Experiments were performed at least 3 times with similar results. Values represent the mean ± SD from triplicate samples. (E) 2E6^– pDCs acquire the expression of Ly49Q. Sorted 2E6^– pDCs derived from bone marrow were cultured in the presence of Flt-3L (100 ng/mL) for 0, 2, and 4 days. Cells were then stained with 2E6 mAb and analyzed by FACS.