CD4 and eosinophilic esophagitis: While IL-5 and IL-13 production was inconsistent among our patients, we did not detect a statistically significant difference in IL-5 or IL-13 production by CD4+ T cells among the groups, suggesting an unappreciated role for TNF-α and IFN-γ producing CD8+ T cells in the progression or persistence of EoE inflammation.