Figure 3.

Schematic model for intracellular pH regulatory circuit in normal and eosinophilic esophagitis (EE) stratified squamous esophageal epithelial cells (modified from Reference [152]). In normal epithelium, intracellular pH is kept balanced by the presence of Na⁺-driven Cl⁻/HCO₃⁻ exchanger (NCBE), Na⁺/H⁺ exchanger (NHE3), and HCO₃⁻/Cl⁻ exchangers (pendrin (PDS), SLC4A2. And SLC4A8). During IL-13 inflammatory conditions in EE, expression of pendrin and NHE3 is increased, leading to unbalanced pH and water influx causing dilated intercellular spaces (DIS) and epithelium disruption.