title: Characterization of the mucocutaneous junction of the human eyelid margin and meibomian glands with different biomarkers.
abstract: OBJECTIVE
  To investigate the morphology of the human eyelid margin and the presence of different cytokeratins, mucins and stem cell markers within the skin epithelium, mucocutaneous junction (MCJ) and palpebral conjunctiva.
  
  
  METHODS
  Eyelids of body donors were investigated histologically and ultrastructurally as well as by immunohistochemical methods using antibodies to cytokeratins 1, 4, 7, 8, 10, 13, 14, 15, and 19; mucins MUC1, MUC4, and MUC5AC and potential stem cell markers K15, BCRP/ABCG2, integrin β1, and N-cadherin.
  
  
  RESULTS
  The expression pattern of cytokeratins, mucins and stem cell markers varied across the different epithelia of the human eyelid. Within the MCJ, CK7, 15 and 19 were absent, whereas the epithelium reacted positive to antibodies to CK1, 4, 8, 10, 13 and 14. Reactivity was also observed for MUC1 and MUC4, but not for MUC5AC. No reactivity was determined for K15, BCRP/ABCG2 and integrin β1 in the area of the MCJ epithelium but a strong reactivity was present for N-cadherin.
  
  
  CONCLUSIONS
  The present immunohistochemical findings lead to a better characterization of the MCJ. Additionally, the knowledge of distribution of biomarkers like cytokeratins, mucins and stem cells can be useful in the investigation of MCJ disturbances which occur in several disorders of the meibomian glands and the lid epithelium in the course of dry eye syndrome and especially meibomian gland dysfunction.
authors.affiliation: Department of Anatomy II, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Ozan Yüksel
authors.initials: OY
authors.lastname: Tektaş
authors.forename: Ajay
authors.initials: A
authors.lastname: Yadav
authors.forename: Fabian
authors.initials: F
authors.lastname: Garreis
authors.forename: Ursula
authors.initials: U
authors.lastname: Schlötzer-Schrehardt
authors.forename: Martin
authors.initials: M
authors.lastname: Schicht
authors.forename: Ulrike
authors.initials: U
authors.lastname: Hampel
authors.forename: Lars
authors.initials: L
authors.lastname: Bräuer
authors.forename: Friedrich
authors.initials: F
authors.lastname: Paulsen
mesh_terms: D000368:Aged; D015415:Biomarkers; D002102:Cadaver; D003228:Conjunctiva / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D005141:Eyelid Diseases / Q000473:pathology; D005143:Eyelids / Q000033:anatomy & histology* / Q000378:metabolism / Q000648:ultrastructure; D005260:Female; D018859:Hair Follicle / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins / Q000378:metabolism; D008297:Male; D008537:Meibomian Glands / Q000033:anatomy & histology* / Q000378:metabolism / Q000648:ultrastructure; D008854:Microscopy, Electron; D008875:Middle Aged; D009077:Mucins / Q000378:metabolism; D009092:Mucous Membrane / Q000378:metabolism / Q000473:pathology; D012879:Skin Physiological Phenomena; D013234:Stem Cells / Q000378:metabolism; D016707:Tissue Fixation
chemical_list: D015415:Biomarkers; D009077:Mucins; D007633:Keratins