CD4 and eosinophilic esophagitis: Moreover, in a mouse model of eosinophilic esophagitis (EoE), RELMα induction by doxycycline (DOX) in the esophagus can promote epithelial cell hyperplasia and basal layer thickness, recruit activated CD4+ and CD4− T cell subsets, and exacerbate eosinophil accumulation [56].