title: Lamina propria dendritic cells express activation markers and contact lymphocytes in chronic periodontitis.
abstract: BACKGROUND
  Dendritic cells are characterized by shape, structure, and membrane molecule expression; they contact T lymphocytes to present antigens and stimulate plasma cell differentiation in vitro. Dendritic cells are known to be present in healthy human gingiva and to be altered in HIV-associated periodontitis. Here, we address the phenotype, location, and intercellular relationships of dendritic cells in chronic periodontitis.
  
  
  METHODS
  Biopsies from patients with chronic periodontitis were analyzed by electron microscopy and indirect immunofluorescence for dendritic cells and lymphocyte markers.
  
  
  RESULTS
  Langerhans' cells were spread in oral epithelium but restricted to the basal layer in pocket epithelium; they did not usually express major histocompatibility complex (MHC)-II antigens nor contact lymphocytes. Dendritic cells were abundant in the lamina propria of pocket epithelium; they were MHC-II positive, admixed with CD4-positive and CD8-positive T lymphocytes, and, they expressed CD54, CD80, and CD86. Dendritic cells often contacted lymphocytes and were also located within plasma cell aggregates.
  
  
  CONCLUSIONS
  The data suggest that prerequisites for mounting a T cell-mediated immune response exist in chronic periodontitis, although this response is limited to the lamina propria. These results suggest that T-cell responses offer limited protection and can contribute to tissue damage during periodontal disease.
authors.affiliation: Department of Anatomy, Histology and Forensic Medicine, University of Florence, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Cirrincione
authors.forename: Nicola
authors.initials: N
authors.lastname: Pimpinelli
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Orlando
authors.forename: Paolo
authors.initials: P
authors.lastname: Romagnoli
mesh_terms: D000368:Aged; D000938:Antigen-Presenting Cells / Q000276:immunology; D015703:Antigens, CD / Q000276:immunology; D018122:B7-1 Antigen / Q000276:immunology; D051940:B7-2 Antigen; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002449:Cell Aggregation; D002454:Cell Differentiation; D002908:Chronic Disease; D003239:Connective Tissue Cells / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology*; D004847:Epithelial Cells / Q000276:immunology; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D005881:Gingiva / Q000276:immunology* / Q000473:pathology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000276:immunology; D007801:Langerhans Cells / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology*; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology; D008854:Microscopy, Electron; D008875:Middle Aged; D010514:Periodontal Pocket / Q000276:immunology / Q000473:pathology; D010518:Periodontitis / Q000276:immunology*; D010641:Phenotype; D010950:Plasma Cells / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; C497964:CD86 protein, human; D000949:Histocompatibility Antigens Class II; D008562:Membrane Glycoproteins; D018799:Intercellular Adhesion Molecule-1