Immunologic response of the laryngeal mucosa to extraesophageal reflux

Objectives: Extraesophageal reflux is common. The treatment costs are high, and there are associations with other diseases, including laryngeal cancer. Our studies of the mucosal immune response to this common inflammatory disease suggest an important role for the nonclassic antigen-presenting molecule CD1d in the response to inflammation. This study was performed to further explore the relationship between the CD1d-NKT cell-iGb3 axis and reflux. Methods: We carried out a prospective study of laryngeal biopsies from 12 patients with laryngopharyngeal reflux and 11 controls. Quantitative multiple-color immunofluorescence using antibodies for lymphocytes (CD3, CD161) and classic and nonclassic major histocompatibility complex (I, II, β2m, CD1d) was performed, and univariate and multivariate analysis and co-localization measurements were applied. Results: Epithelial major histocompatibility complex class I and II expression was unchanged by reflux, but expression of CD1d increased (p < 0.05; luminal layers) and confidence intervals diminished in the reflux group. Co-localization of NKT cells with CD1d increased in patients (p < 0.01); iGb3 exhibited strong expression throughout all layers of the laryngeal epithelium. Conclusions: These data indicate a role for the CD1d-NKT cell-iGb3 axis in response to extraesophageal reflux in humans. This represents a useful target for novel diagnostics and treatments for this common condition.