IFN-α/β mediates the adjuvant property of poly(I:C) and CpG. (A) In vivo production of type I IFN in response to various TLR-L. C57BL/6 mice received a single intravenous injection of zymosan, poly(I:C), LPS, R848, R837, poly(U), or CpG-B. CpG was administered either naked or mixed with DOTAP. As a control, one group of mice received DOTAP alone. Serum samples were collected at various time points after injection of the TLR-L, and IFN-α and IFN-β were titrated by ELISA. Results are expressed as means ± SEM for 3 to 4 mice per group tested in 2 independent experiments. (B) 129Sv and IFNARko mice received a single intravenous injection of poly(I:C) or CpG-B(DOTAP), and their sera were titrated for IFN-α and IFN-β by ELISA. Results are expressed as means ± SEM for 3 mice per group. (C) 129Sv and IFNARko mice were left untreated or were injected intravenously with BOVAp either alone or in combination with poly(I:C) or CpG-B(DOTAP). The specific CTL response was analyzed on day 7 by tetramer staining, in vivo killing assay, and ELISPOT (upper, medium, and lower panels, respectively). All data are representative of at least 2 independent experiments.