Local type 2 immunity in eosinophilic gastritis.

Area of Science:

• Immunology
• Gastroenterology
• Cellular Biology

Background:

• Eosinophilic gastritis (EoG) is linked to type 2 immunity.
• The cellular sources of type 2 cytokines and gastric T-cell composition in EoG are not well understood.
• The relationship between gastric T cells and disease pathology requires further investigation.

Purpose of the Study:

• To define gastric T-cell populations in EoG.
• To investigate the association between gastric T cells and EoG pathology.
• To explore the role of T helper 2 (T_H2) cells and type 2 cytokines in EoG.

Main Methods:

• Gastric biopsy samples from EoG patients and controls were analyzed using histology, endoscopy, and flow cytometry.
• T-cell populations, including regulatory T cells and T_H2 cells, were quantified.
• In a separate cohort, mRNA levels of IL-4, IL-5, and IL-13 were correlated with EoG pathologic parameters.

Main Results:

• Gastric T cells in EoG included increased regulatory T cells and T_H2 cells (CD3⁺CD4⁺GATA3⁺) compared to controls.
• T_H2 cell levels significantly correlated with gastric eosinophil counts, endoscopic findings, and histopathology.
• Elevated IL-4, IL-5, and IL-13 mRNA levels in EoG also correlated with disease severity.

Conclusions:

• Eosinophilic gastritis is associated with an increase in gastric T helper 2 (T_H2) cells.
• These T_H2 cells produce type 2 cytokines and their levels strongly correlate with EoG disease pathology.
• The findings highlight the central role of T_H2 cells in the pathogenesis of EoG.