Local Clinical and Immunological Responses in Eosinophilic Esophagitis (EoE) Patients, Role of Mucosal Barrier Function and Type II Inflammation

Eosinophilic esophagitis (EoE) is an allergic inflammation of the esophagus. If not treated properly, inflammation and narrowing of the esophagus can occur. This can eventually lead to food impaction. Food allergens play an important role in the pathogenesis of EoE, as demonstrated by endoscopic and clinical resolution of EoE once the causative food is removed from the diet and exacerbation when the same food is reintroduced Similarly, amino acid-based

elemental diets are effective in both adults and children with EoE. However, the exact mechanism by which food allergens can initiate inflammation in EoE is still unknown, as there are limited data on the early local esophageal immune response after challenge with a specific food trigger. Previous research has shown that this can be treated with antacids (PPI) and corticosteroids. This reduces the permeability of the esophagus (which is increased in EoE), but not to the level of healthy individuals. Most likely this is due to a mild underlying allergic inflammation that persists under treatment with the above agents. The idea is that dupilumab inhibits this type II inflammation, which will further reduce the permeability. In addition, the effect of food allergens on esophageal biopsies from both EoE patients and healthy patients will be examined. This will then be compared to the biopsies taken after the use of dupilumab.