Immunohistochemical study on distribution of mast cell phenotypes in human laryngeal mucosa: evidence for laryngeal type I allergy.

It is controversial whether or not type I allergic reactions can occur in the human laryngeal mucosa. To clarify this issue, we studied the distribution of mast cell phenotypes in the human laryngeal mucosa using the immunohistochemical staining method with antihuman tryptase and chymase antibodies. A large number of mast cells are present in the superficial layer of subepithelial connective tissue (SECT) of the epiglottis, arytenoid, and subglottis. Although mast cells containing both tryptase and chymase are predominant in the deep layer of the SECT, the majority of mast cells containing tryptase alone are located in both the epithelial layer and the superficial layer of the SECT. We conclude that the human laryngeal mucosa has the potential to induce type I allergic reaction.