In EoE, cell-culture-based studies have shown that pro-fibrotic fibroblast behavior is regulated by Th2 cytokines prevalent in EoE (IL-4, IL-13, IL-5) and TGFβ1 secreted from a number of cells including eosinophils [9]. The gene discussed is TGFB1; the disease is eosinophilic esophagitis.