title: Cell biology of laryngeal epithelial defenses in health and disease: further studies.
abstract: This is the second annual report of an international collaborative research group that is examining the cellular impact of laryngopharyngeal reflux (LPR) on laryngeal epithelium. The results of clinical and experimental studies are presented. Carbonic anhydrase (CA), E-cadherin, and MUC gene expression were analyzed in patients with LPR, in controls, and in an in vitro model. In patients with LPR, we found decreased levels of CAIII in vocal fold epithelium and increased levels in posterior commissure epithelium. The experimental studies confirm that laryngeal CAIII is depleted in response to reflux. Also, cell damage does occur well above pH 4.0. In addition, E-cadherin (transmembrane cell surface molecules, which have a key function in epithelial cell adhesion) was not present in 37% of the LPR laryngeal specimens. In conclusion, the laryngeal epithelium lacks defenses comparable to those in esophageal epithelium, and these differences may contribute to the increased susceptibility of laryngeal epithelium to reflux-related injury.
authors.affiliation: Center for Voice Disorders of Wake Forest University, Department of Otolaryngology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1034, USA.
authors.forename: Nikki
authors.initials: N
authors.lastname: Johnston
authors.forename: David
authors.initials: D
authors.lastname: Bulmer
authors.forename: Gulnaz A
authors.initials: GA
authors.lastname: Gill
authors.forename: Marguerite
authors.initials: M
authors.lastname: Panetti
authors.forename: Peter E
authors.initials: PE
authors.lastname: Ross
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Pearson
authors.forename: Massimo
authors.initials: M
authors.lastname: Pignatelli
authors.forename: Sophie E
authors.initials: SE
authors.lastname: Axford
authors.forename: Peter W
authors.initials: PW
authors.lastname: Dettmar
authors.forename: James A
authors.initials: JA
authors.lastname: Koufman
mesh_terms: D000136:Acid-Base Equilibrium / Q000502:physiology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001706:Biopsy; D015153:Blotting, Western; D015820:Cadherins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D002256:Carbonic Anhydrases / Q000235:genetics* / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism / Q000473:pathology; D004947:Esophagus / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D005764:Gastroesophageal Reflux / Q000150:complications / Q000201:enzymology / Q000473:pathology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007818:Laryngeal Diseases / Q000209:etiology / Q000235:genetics* / Q000473:pathology*; D007820:Laryngeal Mucosa / Q000201:enzymology / Q000276:immunology / Q000473:pathology*; D009077:Mucins / Q000235:genetics* / Q000378:metabolism; D013552:Swine
chemical_list: D000911:Antibodies, Monoclonal; D015820:Cadherins; D009077:Mucins; D002256:Carbonic Anhydrases