title: Recruitment of dendritic cells in oral lichen planus.
abstract: Using immunohistochemistry the presence of different dendritic cell (DC) subsets was analysed in 16 biopsies from patients with oral lichen planus (OLP). A significant increase of CD1a+/Langerin+ Langerhans cells, DC-SIGN+ DC and CD123+/BDCA2+ plasmacytoid DCs (PDCs) was found in the epithelium and in the stroma of OLP biopsies compared to normal oral mucosa. A proportion of DCs were mature DC-LAMP+ and expressed S100 or CD11c, typically found in the interdigitating DCs of nodal T-cell areas. Double staining revealed that mature DCs co-expressed CCR7, thus indicating the development of a nodal migratory phenotype upon maturation. Significant recruitment of PDCs producing IFN-alpha was demonstrated by the expression of MxA within the lichenoid inflammatory infiltrate and close cell-to-cell contacts between PDCs and mature DCs were observed, with a significant correlation between the numbers of these two populations. Moreover, PDCs were also found to contain Granzyme-B, an associated-cytotoxic granule protein, inducing target cell apoptosis. Taken together, these results suggest that PDCs may promote maturation of DCs and amplify the cytotoxicity of lymphoid cells. Finally, the recruitment of different subtypes of DC, such as Langerhans cells, stromal DC-SIGN+ DCs and PDCs, associated with a significant proportion of mature DCs, acquiring a CCR7+ 'migratory' phenotype, indicate that they may play a pivotal role in the development of the lichenoid inflammatory infiltrate that occurs typically in OLP.
authors.affiliation: Department of Pathology, University of Brescia, Spedali Civili Brescia, Brescia, Italy.
authors.forename: Amerigo
authors.initials: A
authors.lastname: Santoro
authors.forename: Alessandra
authors.initials: A
authors.lastname: Majorana
authors.forename: Luca
authors.initials: L
authors.lastname: Roversi
authors.forename: Francesca
authors.initials: F
authors.lastname: Gentili
authors.forename: Simona
authors.initials: S
authors.lastname: Marrelli
authors.forename: William
authors.initials: W
authors.lastname: Vermi
authors.forename: Elena
authors.initials: E
authors.lastname: Bardellini
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Sapelli
authors.forename: Fabio
authors.initials: F
authors.lastname: Facchetti
mesh_terms: D015703:Antigens, CD / Q000032:analysis; D018949:Antigens, CD1 / Q000032:analysis; D000954:Antigens, Surface / Q000032:analysis; D015815:Cell Adhesion Molecules / Q000032:analysis; D003713:Dendritic Cells / Q000737:chemistry / Q000473:pathology*; D004847:Epithelial Cells / Q000737:chemistry / Q000473:pathology; D005455:Fluorescent Antibody Technique / Q000379:methods; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D053650:Interleukin-3 Receptor alpha Subunit; D007801:Langerhans Cells / Q000737:chemistry / Q000473:pathology; D037181:Lectins, C-Type / Q000032:analysis; D017676:Lichen Planus, Oral / Q000378:metabolism / Q000473:pathology*; D051907:Lysosomal Membrane Proteins; D037241:Mannose-Binding Lectins / Q000032:analysis; D008562:Membrane Glycoproteins; D009061:Mouth Mucosa / Q000737:chemistry / Q000473:pathology; D009419:Nerve Tissue Proteins / Q000032:analysis; D010641:Phenotype; D054400:Receptors, CCR7; D011956:Receptors, Cell Surface / Q000032:analysis; D019707:Receptors, Chemokine / Q000032:analysis; D011971:Receptors, Immunologic; D016185:Receptors, Interleukin-3 / Q000032:analysis; D017154:Stromal Cells / Q000737:chemistry / Q000473:pathology; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
chemical_list: D015703:Antigens, CD; D018949:Antigens, CD1; D000954:Antigens, Surface; D015815:Cell Adhesion Molecules; D053650:Interleukin-3 Receptor alpha Subunit; D037181:Lectins, C-Type; D051907:Lysosomal Membrane Proteins; D037241:Mannose-Binding Lectins; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; D054400:Receptors, CCR7; D011956:Receptors, Cell Surface; D019707:Receptors, Chemokine; D011971:Receptors, Immunologic; D016185:Receptors, Interleukin-3; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin; C515370:CCR7 protein, human; C419393:CD1a antigen; C121916:CD207 protein, human; C443299:CLEC4C protein, human; C115022:IL3RA protein, human