Figure 2.

Interleukin-33 (IL-33) expression induced by aryl hydrocarbon receptor (AhR) ligands in THP-1 macrophages. THP-1 macrophages were treated with the AhR agonists 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) (10 nM), 6-Formylindolo(3, 2-b)carbazole (FICZ) (100 nM), or kynurenine (KYN) (50 μM) for 6 h. Total RNA was extracted, and cDNA was synthesized. The mRNA levels of variants 4 and 5 were measured by real-time PCR. 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 < .01 versus the untreated group.