CLDN5 and Crohn disease: Claudin-5 redistribution was also found in colon biopsies of patients with Crohn’s disease (Zeissig et al., 2007) or lymphocytic colitis (Barmeyer et al., 2017) and was mimicked by TNFα and IFNγ in colon epithelial cell lines in vitro (Barmeyer et al., 2017).