Adenoviral delivery of constitutively active STAT3 in IL-10^-/- BMDCs inhibits IL-12p40 mRNA accumulation and protein secretion. IL-10^-/- BMDCs were infected with the constitutively active STAT3 adenovirus (Ad5STAT3C) or the control Ad5GFP and subsequently stimulated with LPS (5 μg/mL). (A) Cells were collected at 4 hours, RNA was isolated, and IL-12p40 and TNFα mRNA accumulation was analyzed by RT-PCR. (B) BMDCs were infected as described in Figure 6, stimulated with LPS (5 μg/mL) for 7 hours, and IL-12p40 secretion was measured by ELISA in triplicate supernatants. ^***P < .005. Results are representative of 2 independent experiments. Error bars represent SEM.