DOCK2 is required for TLR7/9-mediated type I IFN induction in pDCs. (A) Serum IFN-α and IL-12p40 levels were compared between WT and Dock2−/− mice after injection of CpG-A complexed with the cationic lipids DOTAP (left) or R848 (right). Data are the mean ± SD of three mice, and are representative of two independent experiments. **, P < 0.001. (B–I) The levels of IFN-α (B, D, E, G, H, and I), IFN-β (C and E), IL-12p40 (F, G, and I), and IL-6 (F) in cell culture supernatants were compared between WT and Dock2−/− pDCs 24 h after stimulation with TLR7 or TLR9 ligands. Data are expressed as the mean ± SD of triplicate wells and are representative of three (B–G) or two (H and I) independent experiments. **, P < 0.001; *, P < 0.01. ND indicates below the detectable limit. (B, C, D, and F) Flt3 ligand–induced BM–derived pDCs (4 × 104 cells per well) were stimulated with CpG-A (B and C, 0–3 µM; F, 3 µM), CpG-B (B and C, 0–3 µM; F, 1 µM), or R848 (D and F, 100 nM). (E) Naive BM pDCs (4 × 104 cells per well) were stimulated with CpG-A (3 µM). (G) Flt3 ligand–induced BM-derived pDCs (2 × 105 cells per well) were infected with influenza A virus or HSV-2 at the indicated MOIs. (H) Flt3 ligand–induced BM-derived pDCs (2 × 105 cells per well) were stimulated with live or inactivated influenza A virus or HSV-2 at an MOI of 0.5 or 0.3, respectively. (I) Flt3 ligand–induced BM-derived pDCs (4 × 105 cells per well) were stimulated with 2.74 µg/ml HSV-2 DNA.
