CDH26 (cadherin-26) is a calcium-dependent epithelial cell adhesion protein that functions as a key regulator of airway and mucosal barrier integrity and immune responses. Structurally, CDH26 mediates homophilic cell-cell adhesion through interaction with catenin family members (α, β, and p120) and maintains epithelial cytoskeletal organization and apical polarity by preserving cortical actin structures and localizing planar cell polarity proteins 1. CDH26 also binds integrin α4β7 and serves as a ligand for integrins αE and α4, thereby modulating CD4+ T cell activation and facilitating leukocyte adhesion 2. Clinically, CDH26 is a central mediator of type 2 (Th2) inflammatory diseases. In asthma, CDH26 is selectively upregulated among cadherins and amplifies IL-4 receptor signaling in airway epithelial cells, promoting mucus overproduction, airway hyperresponsiveness, and eosinophilia 34. Similarly, in allergic rhinitis and eosinophilic chr20 rhinosinusitis, CDH26 knockdown attenuates inflammatory responses and reduces eosinophil transepithelial migration through IL-4/IL-13-induced upregulation and α4 integrin interaction 56. CDH26 expression correlates with disease severity markers including serum IgE, eosinophilia, and fractional exhaled nitric oxide 7. These findings identify CDH26 as a promising therapeutic target for allergic inflammatory diseases.