title: In Situ Mapping of Innate Lymphoid Cells in Human Skin: Evidence for Remarkable Differences between Normal and Inflamed Skin.
abstract: Although innate lymphoid cells (ILCs) have recently been identified also in skin, their role in this organ remains poorly understood. In this study, we aimed at developing a technique to assess ILCs in situ and to determine their topographical distribution in human skin. We collected lesional skin biopsies from patients with atopic dermatitis and psoriasis (both n = 13) and normal human skin from healthy controls. After establishing immunofluorescence ILC in situ stainings, we developed an analysis approach (gating combined with manual validation) to reliably identify ILCs. Topographical mapping was obtained by automated calculations of the distances between ILCs and different cellular/structural elements of the skin. Whereas normal human skin harbored a very scarce ILC population (mostly ILC1s and AHR+ILC3s), atopic dermatitis and psoriasis skin was infiltrated by clearly visible ILC subsets. We observed atopic dermatitis skin to contain not only ILC2s but also a prominent AHR+ILC3 population. Conversely, we encountered almost equal proportions of ILC1s and RORC+ILC3s in psoriasis skin. Distance calculations revealed ILCs to reside near the epidermis and in close proximity to T lymphocytes. ILC mapping in situ will provide valuable information about their likely communication partners in normal and diseased skin and forms the basis for the appropriate mechanistic studies.
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria; Department of Dermatology, Zurich University Hospital, Zurich, Switzerland.
authors.forename: Marie-Charlotte
authors.initials: MC
authors.lastname: Brüggen
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria.
authors.forename: Wolfgang M
authors.initials: WM
authors.lastname: Bauer
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria.
authors.forename: Bärbel
authors.initials: B
authors.lastname: Reininger
authors.affiliation: Department of Application Support and Image Processing, TissueGnostics srl, Iasi, Romania.
authors.forename: Eduard
authors.initials: E
authors.lastname: Clim
authors.affiliation: Department of Product Development, TissueGnostics srl, Iasi, Romania.
authors.forename: Catalin
authors.initials: C
authors.lastname: Captarencu
authors.affiliation: TissueGnostics GmbH, Vienna, Austria.
authors.forename: Georg E
authors.initials: GE
authors.lastname: Steiner
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria.
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Brunner
authors.affiliation: Department of Dermatology, Zurich University Hospital, Zurich, Switzerland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Meier
authors.affiliation: Department of Dermatology, Zurich University Hospital, Zurich, Switzerland.
authors.forename: Lars E
authors.initials: LE
authors.lastname: French
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria. Electronic address: georg.stingl@meduniwien.ac.at.
authors.forename: Georg
authors.initials: G
authors.lastname: Stingl
mesh_terms: D000465:Algorithms; D000704:Analysis of Variance; D001707:Biopsy, Needle; D002478:Cells, Cultured; D003876:Dermatitis, Atopic / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007113:Immunity, Innate / Q000276:immunology*; D017403:In Situ Hybridization / Q000379:methods*; D015851:Interleukin-7 / Q000276:immunology; D015603:Keratinocytes / Q000276:immunology / Q000473:pathology; D008214:Lymphocytes / Q000276:immunology / Q000473:pathology*; D011565:Psoriasis / Q000276:immunology / Q000473:pathology*; D012016:Reference Values; D015203:Reproducibility of Results; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D012867:Skin / Q000276:immunology / Q000473:pathology
chemical_list: D015851:Interleukin-7