Crystalline Insights into Nasal Mucosa Inflammation and Remodeling: Unveiling Role of Galectin-10

Background: Galectin-10 (Gal-10), the main constituent of Charcot–Leyden crystals, is a recognized marker of eosinophilic inflammation, yet its role in nasal mucosal remodeling in Seasonal Allergic Rhinitis (SAR) remains poorly defined. Methods: Gal-10, IL-5, MUC5AC, and IFN-γ were analyzed in Nasal lavage (NL) samples from children with SAR by ELISA. Unsupervised clustering and discriminant analyses were applied. The functional effects of Gal-10 were investigated ex vivo using a 3D epithelial–mesenchymal trophic unit (EMTU) model stimulated with NL containing high, low, or depleted Gal-10 levels. EMT (epithelial–mesenchymal transition) markers (vimentin, E-cadherin, SNAIL1) and MUC5AC secretion were assessed by immunohistochemistry, Western blot, and ELISA. Results: Gal-10 levels in NL positively correlated with IL-5 and MUC5AC and inversely with IFN-γ. Clustering analysis identified distinct SAR endotypes, with Gal-10 showing the highest discriminative power. In the 3D EMTU model, high Gal-10 NL induced increased vimentin and SNAIL1 expression and enhanced MUC5AC secretion, effects attenuated after Gal-10 depletion. Conclusions: Gal-10 is associated with Th2-type inflammation, mucus hypersecretion, and early epithelial–mesenchymal transition in pediatric SAR, supporting its role as a mediator of nasal mucosal remodeling and a potential therapeutic target