Eosinophilic esophagitis (EoE) is a chronic inflammatory disease associated with marked eosinophil infiltration in the esophageal epithelium.1, 2, 3 EoE is a T-cell dependent, Th2 cytokine-mediated allergic disease, and it has been shown that IL-15 is critical in the initiation and progression of EoE.4, 5, 6, 7 IL-15 has the ability to stimulate, proliferate and differentiate T cells and is essential for the growth and survival of CD8+ T cells, NK cells and iNKT cells. This evidence concerns the gene CD8A and eosinophilic esophagitis.