VV-induced production of proinflammatory cytokines is mediated by TLR2. DCs were generated from bone marrow cells of wild-type C57BL/6 (WT), TLR2^−/−, TLR4^−/−, or TLR9^−/− mice in the presence of GM-CSF and IL-4 for 5 days. On day 5, immature DCs were stimulated with VV, PGN, or LPS for 18 hours. Supernatants were then analyzed by ELISA for secretion of IL-6 (A) and IL-1 (B). Error bars indicate SD.