CLDN1 and eosinophilic esophagitis: Other downregulated junctional proteins in the esophageal mucosa of patients with EoE include E-cadherin, claudin-1 and 7 (Abdulnour-Nakhoul et al., 2013; Nguyen et al., 2018), zonulin-1 (Katzka et al., 2014), and desmoglein-1 (DSG1) (Sherrill et al., 2014a).