Langerhans cells in the larynx and the hypopharynx.

Langerhans cells are important in the human immune system as a part of the dendritic cell system. This study was carried out to demonstrate the presence of Langerhans cells and their distribution in normal human larynx and hypopharynx, by light (S-100 polyclonal antibody) and transmission electron microscopy. The results are summarized as follows: 1) Langerhans cells with cytoplasmic granules (Langerhans granules or Birbeck's granules) were situated in the suprabasal region of the squamous epithelium in the larynx and the hypopharynx. 2) They distributed in the membranous portion of the vocal folds, epiglottis, aryepiglottic folds, arytenoid regions and interarytenoid notch of the larynx. The cells surrounded the vestibule and glottis of the larynx. 3) They distributed in the postcricoid area, piriform sinus and posterior pharyngeal wall of the hypopharynx. The cells were situated above the entrance of esophagus. 4) The cells were suggested to be a factor of immune response at the entrance of trachea and esophagus.