IL4 and eosinophilic esophagitis: Eosinophilic esophagitis (EoE) is an immunologic disorder with manifestations mediated by Th2 cytokines such as interleukin (IL)-4 and IL-13.[1] Eosinophils accumulate in the esophagus of EoE patients when Th2 cytokines stimulate signal transducer and activator of transcription (STAT)6 signaling in esophageal epithelial cells, causing them to produce eotaxin-3, a potent eosinophil chemoattractant that draws circulating eosinophils into the esophagus.[2, 3] Most reports involving the histology of EoE have focused on epithelial findings in esophageal pinch biopsy specimens.