title: The membrane-associated MUC1 improves adhesion of salivary MUC5B on buccal cells. Application to development of an in vitro cellular model of oral epithelium.
abstract: OBJECTIVE
  The mucosal pellicle is a thin layer of salivary proteins, mostly MUC5B mucins, anchored to epithelial oral cells. This pellicle is involved in protection of oral mucosae against abrasion, pathogenic microorganisms or chemical xenobiotics. The present study aimed at studying the involvement of MUC1 in mucosal pellicle formation and more specifically in salivary MUC5B binding using a cell-based model of oral epithelium.
  
  
  METHODS
  MUC1 mRNAs were not detected in TR146 cells, and therefore a stable cell line named TR146/MUC1 expressing this protein was developed by transfection. TR146 and TR146/MUC1 were incubated with human saliva in order to evaluate retention of MUC5B by epithelial cells.
  
  
  RESULTS
  The cell surface of both TR146 and TR146/MUC1 was typical of a squamous non-keratinized epithelium, with the presence of numerous microplicae. After incubation for 2h with saliva diluted in culture medium (1:1) and two washes with PBS, saliva deposits on cells appeared as a loose filamentous thin network. MUC5B fluorescent immunostaining evidenced a heterogeneous lining of confluent cell cultures by this salivary mucin but with higher fluorescence on TR146/MUC1 cells. Semi-quantification of MUC5B bound to cells confirmed a better retention by TR146/MUC1, evaluated by Dot Blot (+34.1%, p<0.05) or by immunocytochemistry (+44%, p<0.001).
  
  
  CONCLUSIONS
  The membrane-bound mucin MUC1 is a factor enhancing the formation of the mucosal pellicle by increasing the binding of salivary MUC5B to oral epithelial cells. An in vitro model suitable to study specifically the function and properties of the mucosal pellicle is proposed.
authors.affiliation: CNRS, UMR 6265 Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France; INRA, UMR1324 Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France; Université de Bourgogne, UMR Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France.
authors.forename: Sarah
authors.initials: S
authors.lastname: Ployon
authors.affiliation: CNRS, UMR 6265 Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France; INRA, UMR1324 Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France; Université de Bourgogne, UMR Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Belloir
authors.affiliation: Université de Bourgogne, UMR 1347 Agroécologie, Plateforme DImaCell, Centre de Microscopie INRA/Université de Bourgogne, F-21000 Dijon, France.
authors.forename: Aline
authors.initials: A
authors.lastname: Bonnotte
authors.affiliation: INRA, UMR1347 Agroécologie, ERL CNRS 6300, Plateforme DImaCell, Centre de Microscopie INRA/Université de Bourgogne, F-21000 Dijon, France.
authors.forename: Jeannine
authors.initials: J
authors.lastname: Lherminier
authors.affiliation: CNRS, UMR 6265 Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France; INRA, UMR1324 Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France; Université de Bourgogne, UMR Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France.
authors.forename: Francis
authors.initials: F
authors.lastname: Canon
authors.affiliation: CNRS, UMR 6265 Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France; INRA, UMR1324 Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France; Université de Bourgogne, UMR Centre des Sciences du GoÛt et de l'Alimentation, F-21000 Dijon, France. Electronic address: martine.morzel@dijon.inra.fr.
authors.forename: Martine
authors.initials: M
authors.lastname: Morzel
mesh_terms: D002448:Cell Adhesion; D002460:Cell Line; D044622:Dental Pellicle / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism*; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D009061:Mouth Mucosa / Q000378:metabolism*; D018396:Mucin-1 / Q000096:biosynthesis*; D055257:Mucin-5B / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012463:Saliva / Q000737:chemistry; D012471:Salivary Proteins and Peptides / Q000502:physiology*; D014162:Transfection
chemical_list: C524578:MUC5B protein, human; D018396:Mucin-1; D055257:Mucin-5B; D012471:Salivary Proteins and Peptides
keywords: Immunocytochemistry; Mucins; Mucosal pellicle; Oral mucosa; Scanning electron microscopy; TR146 cells