title: Intra-epithelial subpopulations of T lymphocytes and Langerhans cells in oral lichen planus.
abstract: This study has addressed the question of whether there is selective recruitment and distribution of intra-epithelial leucocytes in lesions of oral lichen planus (OLP). T-lymphocyte subsets were examined in the epithelium and peripheral blood of patients and controls using flow cytometry and double immunofluorescence, and the relationship between keratinocyte intercellular adhesion molecule-1 (ICAM-1) expression with T-lymphocyte and Langerhans cell (LC) distribution was examined. The circulating 'memory' subset (CD45RO+) of T-helper cells (CD4+) was increased from 49.1% in controls to 65.7% in patients (P=0.005), while the 'naive' subset (CD45RA+), which was absent from control epithelium, comprised 24% of helper cells in OLP (P=0.016). Fewer LC expressed CD45RO in OLP than in controls (P=0.037) and all T-cell and LC counts were significantly raised in ICAM-1-expressing areas of epithelium. These data demonstrate changes in intra-epithelial T-lymphocyte and LC populations compared with normal oral mucosa and suggest there is selective recruitment in OLP. In addition, keratinocyte ICAM-1 expression does appear to be associated with accumulation of infiltrating T lymphocytes and LC.
authors.affiliation: Department of Oral Pathology, St Bartholomew's and the Royal London School of Medicine and Dentistry, England.
authors.forename: L J
authors.initials: LJ
authors.lastname: Walton
authors.forename: M G
authors.initials: MG
authors.lastname: Macey
authors.forename: M H
authors.initials: MH
authors.lastname: Thornhill
authors.forename: P M
authors.initials: PM
authors.lastname: Farthing
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000473:pathology; D002452:Cell Count; D003713:Dendritic Cells / Q000473:pathology; D004848:Epithelium / Q000473:pathology; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis / Q000235:genetics; D015603:Keratinocytes / Q000473:pathology; D007801:Langerhans Cells / Q000473:pathology*; D017493:Leukocyte Common Antigens / Q000032:analysis; D017676:Lichen Planus, Oral / Q000097:blood / Q000473:pathology*; D018655:Lymphocyte Count; D009061:Mouth Mucosa / Q000473:pathology*; D016176:T-Lymphocyte Subsets / Q000473:pathology; D013601:T-Lymphocytes / Q000473:pathology*; D006377:T-Lymphocytes, Helper-Inducer / Q000473:pathology
chemical_list: D018799:Intercellular Adhesion Molecule-1; D017493:Leukocyte Common Antigens