title: Oral lichen planus: immunohistology of mucosal lesions.
abstract: BACKGROUND
  Current evidence suggests that immunological mechanisms are involved in oral lichen planus (OLP) pathogenesis. The events implicate activated epithelia that comprise antigen-presenting Langerhans cells, immunocompetent keratinocytes and subepithelial inflammatory infiltrate. Also, the presence of a high density of leucocyte cells may occur for the expression of a variety of adhesion molecules. The aim of this study was to analyse the immunoexpression of some adhesion molecules as well as lymphocytic markers in order to determine the disease pathogenesis in a Venezuelan population.
  
  
  METHODS
  The 18 OLP and 10 normal oral mucosa biopsies were immunostained for CD4, CD8, CD1a, LFA-1, VCAM-1 and ICAM-1.
  
  
  RESULTS
  The results showed an increased number of CD4+, CD8+, CD1a+ cells in OLP. Serial sections showed CD4+ and CD8+ cells also expressed LFA-1. The expression of ICAM-1 and VCAM-1 were significantly higher in OLP.
  
  
  CONCLUSIONS
  The immunological reaction begins with Langerhans cells activation, which presents an antigen to CD4+ lymphocytes. Those cells through ICAM-1 and LFA-1 promote epithelial destruction. Afterwards, cytokine production, ICAM-1 and VCAM-1 expression can activate CD8+ lymphocytes leading to the chronic form of the disease.
authors.affiliation: Instituto de Investigaciones Odontológicas Raúl Vincentelli, Universidad Central de Venezuela, Caracas, Venezuela. mvillarr@eastman.ucl.ac.uk
authors.forename: Mariana
authors.initials: M
authors.lastname: Villarroel Dorrego
authors.forename: María
authors.initials: M
authors.lastname: Correnti
authors.forename: Rafael
authors.initials: R
authors.lastname: Delgado
authors.forename: Felix J
authors.initials: FJ
authors.lastname: Tapia
mesh_terms: D018949:Antigens, CD1 / Q000032:analysis; D015704:CD4 Antigens / Q000032:analysis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology; D016827:CD8 Antigens / Q000032:analysis; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology; D004847:Epithelial Cells / Q000276:immunology / Q000473:pathology; D005260:Female; D006801:Humans; D007121:Immunocompetence / Q000276:immunology; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis; D015603:Keratinocytes / Q000276:immunology / Q000473:pathology; D007801:Langerhans Cells / Q000276:immunology / Q000473:pathology; D007958:Leukocyte Count; D007962:Leukocytes / Q000276:immunology / Q000473:pathology; D017676:Lichen Planus, Oral / Q000276:immunology* / Q000473:pathology; D008213:Lymphocyte Activation / Q000276:immunology; D016169:Lymphocyte Function-Associated Antigen-1 / Q000032:analysis; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000276:immunology / Q000473:pathology; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology; D019010:Vascular Cell Adhesion Molecule-1 / Q000032:analysis
chemical_list: D018949:Antigens, CD1; C419393:CD1a antigen; D015704:CD4 Antigens; D016827:CD8 Antigens; D016169:Lymphocyte Function-Associated Antigen-1; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1