title: Identification of novel immune and barrier genes in atopic dermatitis by means of laser capture microdissection.
abstract: BACKGROUND
  The molecular signature of atopic dermatitis (AD) lesions is associated with TH2 and TH22 activation and epidermal alterations. However, the epidermal and dermal AD transcriptomes and their respective contributions to abnormalities in respective immune and barrier phenotypes are unknown.
  
  
  OBJECTIVE
  We sought to establish the genomic profile of the epidermal and dermal compartments of lesional and nonlesional AD skin compared with normal skin.
  
  
  METHODS
  Laser capture microdissection was performed to separate the epidermis and dermis of lesional and nonlesional skin from patients with AD and normal skin from healthy volunteers, followed by gene expression (microarrays and real-time PCR) and immunostaining studies.
  
  
  RESULTS
  Our study identified novel immune and barrier genes, including the IL-34 cytokine and claudins 4 and 8, and showed increased detection of key AD genes usually undetectable on arrays (ie, IL22, thymic stromal lymphopoietin [TSLP], CCL22, and CCL26). Overall, the combined epidermal and dermal transcriptomes enlarged the AD transcriptome, adding 674 upregulated and 405 downregulated differentially expressed genes between lesional and nonlesional skin to the AD transcriptome. We were also able to localize individual transcripts as primarily epidermal (defensin, beta 4A [DEFB4A]) or dermal (IL22, cytotoxic T-lymphocyte antigen 4 [CTLA4], and CCR7) and link their expressions to possible cellular sources.
  
  
  CONCLUSIONS
  This is the first report that establishes robust epidermal and dermal genomic signatures of lesional and nonlesional AD skin and normal skin compared with whole tissues. These data establish the utility of laser capture microdissection to separate different compartments and cellular subsets in patients with AD, allowing localization of key barrier or immune molecules and enabling detection of gene products usually not detected on arrays.
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY; Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Hitokazu
authors.initials: H
authors.lastname: Esaki
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY; Molecular Biomedicine, LEO Pharma, Ballerup, Denmark; Center for Microbial Biotechnology, DTU Systems Biology, Technical University of Denmark, Lyngby, Denmark.
authors.forename: David A
authors.initials: DA
authors.lastname: Ewald
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY; Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Ungar
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY; Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Mariya
authors.initials: M
authors.lastname: Rozenblit
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY.
authors.forename: Xiuzhong
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY.
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY; Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Yeriel D
authors.initials: YD
authors.lastname: Estrada
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY; Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Xiangyu
authors.initials: X
authors.lastname: Peng
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Mitsui
authors.affiliation: Molecular Biomedicine, LEO Pharma, Ballerup, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Litman
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY.
authors.forename: Mayte
authors.initials: M
authors.lastname: Suárez-Fariñas
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY.
authors.forename: James G
authors.initials: JG
authors.lastname: Krueger
authors.affiliation: Laboratory for Investigative Dermatology, Rockefeller University, New York, NY; Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY. Electronic address: Emma.Guttman@mountsinai.org.
authors.forename: Emma
authors.initials: E
authors.lastname: Guttman-Yassky
mesh_terms: D000328:Adult; D003876:Dermatitis, Atopic / Q000235:genetics* / Q000276:immunology; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D061346:Laser Capture Microdissection; D008297:Male; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D060888:Real-Time Polymerase Chain Reaction; D012867:Skin / Q000378:metabolism*
keywords: Atopic dermatitis; IL-34; barrier; claudins 8 and 4; immune; laser capture microdissection