Methods: Peripheral blood mononuclear cells (PBMCs) from 10 children with active EoE, 4 children with controlled EoE, 10 healthy pediatric controls, 7 adults with active EoE and 4 healthy adult controls were collected. CD4IL-17+ cells were quantified at baseline. The PBMCs were incubated with or without anti-CD3/CD28 beads and CD4IL-17+ levels were assessed after 7 days via flow cytometry.
Results: Children with EoE had lower levels of CD4IL-17+ compared to healthy controls (median ± standard error (SE): 0.061 ± 0.168 vs 1.49 ± 0.443 respectively p<0.02). Children with active EoE had lower levels of CD4IL-17+ compared to adults with active disease (0.052 ± 0.012 vs 0.4 ± 0.067, p<0.02). PBMCs that were cultured with anti-CD3/CD28 beads displayed an increase in CD4 IL-17+ compared to untreated cultures, but only in adult controls (14.10 ± 11.53 vs 0.0790 ± 0.1023, p<0.03).
Conclusions: This data suggests that Th17 cells are involved in the pathogenesis of EoE. Expression of IL-17 varies between children and adults with active disease, which may contribute to the age-related variation seen in EoE.