Based on their relevance in CD pathogenesis, IFNγ (32, 33) and the gliadin peptide p31-43 (34, 35), as well as a synthetic TLR3 ligand, poly I:C, which is known to induce IL-33 expression in different cell lines and murine models (36–38) were evaluated in an in vitro assay using the human intestinal epithelial cell line, HT29. Here, TLR3 is linked to Cowden disease.