title: Expression of C-type lectin receptors by subsets of dendritic cells in human skin.
abstract: C-type lectins are cell surface receptors that recognize carbohydrate structures which are often part of microbial pathogens. Several of these molecules are expressed on dendritic cells and are involved in antigen uptake. Expression of C-type lectins on dendritic cells of the human skin, i.e. Langerhans cells of the epidermis and dermal dendritic cells, has been incompletely studied to date. We therefore investigated C-type lectins in situ and on dendritic cells obtained by migration from skin explants by immunofluorescence and flow cytometry. Emphasis was laid on expression patterns of DEC-205/CD205 and BDCA-2, a marker for plasmacytoid dendritic cells. Langerhans cells in situ expressed low levels of DEC-205. Expression was upregulated upon maturation in skin explant organ culture. Most dermal dendritic cells were found to be positive for DEC-205 and DC-SIGN/CD209. Few BDCA-2-expressing cells were found in most skin samples. They were located in small groups in the dermis close beneath the basement membrane. The vast majority of all types of dendritic cells in normal human skin was of immature phenotype, i.e. did not express DC-LAMP/CD208. It is concluded that normal appearing human skin harbors different subsets of dendritic cells including few scattered BDCA-2-expressing cells, presumably plasmacytoid dendritic cells, expressing variable sets of C-type lectin receptors. This may critically contribute to the capacity of the skin immune system to flexibly respond to the world of microbial pathogens.
authors.affiliation: Departments of Dermatology, Innsbruck Medical University, Innsbruck, Austria.
authors.forename: Susanne
authors.initials: S
authors.lastname: Ebner
authors.forename: Zita
authors.initials: Z
authors.lastname: Ehammer
authors.forename: Sandra
authors.initials: S
authors.lastname: Holzmann
authors.forename: Philipp
authors.initials: P
authors.lastname: Schwingshackl
authors.forename: Markus
authors.initials: M
authors.lastname: Forstner
authors.forename: Patrizia
authors.initials: P
authors.lastname: Stoitzner
authors.forename: Georg M
authors.initials: GM
authors.lastname: Huemer
authors.forename: Peter
authors.initials: P
authors.lastname: Fritsch
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Romani
mesh_terms: D015703:Antigens, CD / Q000032:analysis / Q000276:immunology / Q000378:metabolism; D000954:Antigens, Surface / Q000032:analysis / Q000276:immunology / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000032:analysis / Q000276:immunology / Q000378:metabolism; D002465:Cell Movement / Q000276:immunology / Q000502:physiology; D003713:Dendritic Cells / Q000145:classification / Q000276:immunology*; D003872:Dermatitis / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D004817:Epidermis / Q000737:chemistry; D006801:Humans; D007120:Immunochemistry; D066298:In Vitro Techniques; D007801:Langerhans Cells / Q000276:immunology / Q000378:metabolism; D037181:Lectins, C-Type / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D037241:Mannose-Binding Lectins / Q000032:analysis / Q000276:immunology / Q000378:metabolism; D008562:Membrane Glycoproteins; D015778:Minor Histocompatibility Antigens; D011956:Receptors, Cell Surface / Q000032:analysis / Q000276:immunology / Q000378:metabolism; D011971:Receptors, Immunologic; D012867:Skin / Q000166:cytology / Q000276:immunology*; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
chemical_list: D015703:Antigens, CD; D000954:Antigens, Surface; D015815:Cell Adhesion Molecules; D037181:Lectins, C-Type; D037241:Mannose-Binding Lectins; D008562:Membrane Glycoproteins; D015778:Minor Histocompatibility Antigens; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin; C121916:CD207 protein, human; C443299:CLEC4C protein, human; C093569:DEC-205 receptor