E2 down-regulates the antiviral response induced by RNA viruses but not by TLR agonist. (A) Cytokine levels measures by ELISA from DCs pretreated for 24 hours with 10 μg/mL E2 and infected with Influenza A (Flu) or SeV at an MOI of 0.5 for 9 hours. Data are presented as mean plus or minus SD from 4 independent experiments.*P < .05 or **P < .001 versus infected DCs. (B) RIG-I, IP-10, and MxA levels measured by qRT-PCR from DCs pretreated for 24 hours with 10 μg/mL E2 and infected with Influenza A (Flu) or SeV at an MOI of 0.5 for 9 hours. Data are presented as mean plus or minus SD from 4 independent experiments. *P < .05 or **P < .001 versus infected DCs. (C) Cytokine levels measured by ELISA from DCs pretreated for 24 hours with 10 μg/mL E2 before TLR 3, 4, and 7/8 activation.