MyD88 is required for the induction of proinflammatory cytokines by VV, whereas secretion of IFN-β is independent of MyD88 or TRIF. DCs were generated from bone marrow cells of wild-type C57BL/6 (WT), MyD88^−/− or TRIF^−/− mice in the presence of GM-CSF and IL-4 for 5 days. On day 5, immature DCs were stimulated with VV at an MOI of 1 for 18 hours. Supernatants were then analyzed by ELISA for secretion of IL-6 (A), IL-1 (B), and IFN-β (D). DCs were also stimulated with poly (I:C) for 18 hours and assayed for secretion of IL-6 (C). Results are expressed as mean ± SD.