To confirm that the regulatory effect of NPD-0414-2 and NPD-0414-24 on cytokine expression was strictly dependent on the activation of AhR, anti-CD3/CD28-activated IBD LPMC were treated with Ficz, NPD-0414-2 or NPD-0414-24 in the presence or absence of CH223191, a specific inhibitor of the interaction between AhR and its ligands. Here, CD28 is linked to inflammatory bowel disease.