Local type 2 immunity in eosinophilic gastritis.

[Display omitted] Eosinophilic gastritis (EoG) associates with type 2 immunity. However, the type 2 cytokine cellular source, gastric T-cell composition, and gastric T-cell relationship (or relationships) with disease pathology remain understudied. We defined gastric T-cell populations and their association with histologic and endoscopic EoG pathology. Gastric biopsy samples (n = 6 EoG, n = 7 control) were subjected to histologic, endoscopic, and flow cytometry analyses. In a complementary cohort (n = 83 EoG), IL4, IL5, and IL13 mRNA levels were correlated with EoG pathologic parameters. Gastric biopsy samples contained CD3⁺ T cells that were mainly CD8⁺; the CD8/CD4 ratio was comparable in EoG and control biopsy samples (5.7 ± 3.0 and 4.3 ± 0.6, respectively; P =.28). Gastric regulatory T (CD3⁺CD4⁺FOXP3⁺) and T H 2 (CD3⁺CD4⁺GATA3⁺) cell levels were increased in EoG versus controls (2-fold, P <.05 and 10-fold, P <.001, respectively) and correlated with gastric eosinophil levels (r = 0.63, P <.05 and r = 0.85, P <.001, respectively), endoscopic pathology (r = 0.56, P <.01; r = 0.84, P <.001, respectively), and histopathology (r = 0.72, P <.01; r = 0.82, P <.01, respectively). Cytokine-positive, most notably IL-4⁺, T H 2 cell levels strongly correlated with histologic and endoscopic scores (r = 0.82, P <.0001 and r = 0.78, P <.0001, respectively). In an independent EoG cohort (n = 83), bulk gastric IL4 , IL5 , and IL13 mRNA levels correlated with histologic score (r = 0.22, P <.005; r = 0.54, P <.0001; and r = 0.36, P <.0001, respectively) and endoscopic score (r = 0.27, P <.001; r = 0.40, P <.0001; and r = 0.35, P <.0001, respectively). EoG is a T H 2 cell–associated disease featuring increased gastric type 2 cytokine–producing CD3⁺CD4⁺GATA3⁺T H 2 cells that strongly correlate with disease pathologies. [ABSTRACT FROM AUTHOR]