title: Expression patterns of tight junction components induced by CD24 in an oral epithelial cell-culture model correlated to affected periodontal tissues.
abstract: OBJECTIVE
  Previously we demonstrated uniformly strong expression of CD24 in the epithelial attachment to the tooth and in the migrating epithelium of the periodontitis lesion. Titers of serum antibodies autoreactive with CD24 peptide correlated with reduced severity of periodontal disease. Ligation of CD24 expressed by oral epithelial cells induced formation of tight junctions that limited paracellular diffusion. In this study, we aimed to reveal that the lack of uniform expression of tight junction components in the pocket epithelium of periodontitis lesions is likely to contribute to increased paracellular permeability to bacterial products. This is proposed as a potential driver of the immunopathology of periodontitis.
  
  
  METHODS
  An epithelial culture model with close correspondence for expression patterns for tight junction components in periodontal epithelia was used. Immunohistochemical staining and confocal laser scanning microscopy were used to analyse patterns of expression of gingival epithelial tight junction components.
  
  
  RESULTS
  The minimally inflamed gingival attachment was characterized by uniformly strong staining at cell contacts for the tight junction components zona occludens-1, zona occludens-2, occludin, junction adhesion molecule-A, claudin-4 and claudin-15. In contrast, the pocket epithelium of the periodontal lesion showed scattered, uneven staining for these components. This pattern correlated closely with that of unstimulated oral epithelial cells in culture. Following ligation of CD24 expressed by these cells, the pattern of tight junction component expression of the minimally inflamed gingival attachment developed rapidly.
  
  
  CONCLUSIONS
  There was evidence for non-uniform and focal expression only of tight junction components in the pocket epithelium. In the cell-culture model, ligation of CD24 induced a tight junction expression profile equivalent to that observed for the minimally inflamed gingival attachment. Ligation of CD24 expressed by gingival epithelial cells by lectin-like receptors of commensal oral streptococci could mediate the phenotype of health, whereas pathogenic organisms associated with periodontal disease might not signal effectively through CD24.
authors.affiliation: Institute of Dental Research, Westmead Millennium Institute, Westmead Hospital, Westmead, Australia; Westmead Centre for Oral Health, Westmead Hospital, Westmead, Australia.
authors.forename: P
authors.initials: P
authors.lastname: Ye
authors.forename: H
authors.initials: H
authors.lastname: Yu
authors.forename: M
authors.initials: M
authors.lastname: Simonian
authors.forename: N
authors.initials: N
authors.lastname: Hunter
mesh_terms: D051927:CD24 Antigen / Q000276:immunology*; D018929:Cell Culture Techniques; D002478:Cells, Cultured; D055113:Chronic Periodontitis / Q000276:immunology / Q000473:pathology; D062506:Claudin-4 / Q000032:analysis; D057167:Claudins / Q000032:analysis; D004846:Epithelial Attachment / Q000276:immunology / Q000473:pathology; D004847:Epithelial Cells / Q000276:immunology; D005881:Gingiva / Q000276:immunology* / Q000473:pathology; D005891:Gingivitis / Q000276:immunology / Q000473:pathology; D006801:Humans; D062726:Junctional Adhesion Molecules / Q000032:analysis; D018613:Microscopy, Confocal; D062793:Occludin / Q000032:analysis; D010514:Periodontal Pocket / Q000276:immunology / Q000473:pathology; D010539:Permeability; D062725:Tight Junction Proteins / Q000032:analysis / Q000276:immunology*; D019108:Tight Junctions / Q000276:immunology*; D062826:Zonula Occludens-1 Protein / Q000032:analysis; D062827:Zonula Occludens-2 Protein / Q000032:analysis
chemical_list: D051927:CD24 Antigen; C497889:CD24 protein, human; C568157:CLDN4 protein, human; D062506:Claudin-4; D057167:Claudins; D062726:Junctional Adhesion Molecules; C568985:OCLN protein, human; D062793:Occludin; C569042:TJP1 protein, human; D062725:Tight Junction Proteins; D062826:Zonula Occludens-1 Protein; D062827:Zonula Occludens-2 Protein; C459596:claudin 15
keywords: CD24; cell culture; periodontitis; tight junction