Surface Expression of Intercellular Adhesion Molecule 1 on Epithelial Cells in the Human Adenoid

Human rhinoviruses enter the host by way of the nose and conjunctiva. Intercellular adhesion molecule 1 (ICAM-1) is the cellular receptor for the majority of rhinoviruses. ICAM-1 expression on the luminal surface of epithelial cells in the upper airway may be an important determinant of virus localization in the airway. Eighteen adenoids and 5 nasopharyngeal biopsies were evaluated by immunohistochemistry for surface expression of ICAM-1. Heavy immunoreactivity of ICAM-1 was found on the surface of a small number of single nonciliated cells in the lymphoepithelium. Squamous epithelial cells showed minimal to no staining, and ciliated epithelium had positive ICAM-1 staining of the basal cells but not on the ciliated border. The localization of ICAM-1 expression to specific, limited areas of the surface epithelium of the nasopharynx may have important implications in the pathogenesis of rhinovirus infections, especially initiation of the host response to rhinovirus.