OCLN and Chronic colitis: It was previously demonstrated that the pro-inflammatory response and intestinal barrier dysfunction and disruption go hand in hand in the development of chronic colitis in the T cell transfer model, shown by an increased 4 kDa FITC-dextran permeability and an altered mRNA expression of the junctional proteins Cldn1, Cldn2, Cdh1 and Ocln (Breugelmans et al., 2020).