Protocol for Food Antigen Staining in Esophageal Mucosa in Patients With Eosinophilic Esophagitis

One of the putative mechanisms of eosinophilic esophagitis is exposure of food antigens to antigen recognition cells in the esophageal mucosa that initiates a chronic allergy-based inflammatory response . It is believed that this exposure is facilitated through dilation of the intercellular spaces (DIS) between esophageal epithelial cells (termed spongiosis). This is substantiated by several studies which have demonstrated that: first, DIS is commonly found in biopsies from patients with active EoE and reverses with steroid therapy; second, DIS correlates to physiologic demonstration of increased esophageal epithelial permeability as shown through transepithelial small molecule flux in mucosal biopsies appraised in Ussing chambers and increased conductivity of electric current as measured in a mucosal impedance probe (Katzka, et al., in press, Clin Gastroenterol Hepatol). Although these mechanisms make intuitive sense, no one has shown the presence of food antigen in esophageal mucosa after ingestion and the correlation of this presence to dilation of intercellular spaces.