Figure 5.

Involvement of the dioxin response element (DRE) located in the interleukin-33 (IL-33) promoter region in aryl hydrocarbon receptor (AhR)-induced IL-33 expression. A, The DRE sequences identified in the human IL-33 promoter region are named DRE1 and DRE2. B, THP-1 macrophages were transfected with pNL containing the human IL-33 promoter harboring wild-type DREs, the DRE1 mutation (DRE1m) or the DRE2 mutation (DRE2m) and then treated with 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) (10 nM) and kynurenine (KYN) (50 μM) for 6 h. The cells were collected and lysed to measure luciferase activity. The values represent the mean ± SE (n = 6). Data were analyzed using a one-way analysis of variance (ANOVA), followed by Dunnett's test. *p < .5, **p < .01 versus the untreated group.