Effects of T. spiralis ES products on the expression of IDO and cytokine mRNAs in DC2.4 cells. DCs were treated with 15 μg/mL ES products from T. spiralis for 0, 2, 6, 12, 24, 36, 48, or 72 h. IFN-γ was used as a positive control in these experiments. (A–D) Real-time RT-PCR was performed to identify the relative expression of IDO, IFN-γ, IL-10, and TNF-α mRNAs in DCs. *p < 0.05, **p < 0.01, and ***p < 0.001.