title: Plasmacytoid dendritic cells and interferon levels are increased in lymphatic malformations.
abstract: OBJECTIVE
  Describe the presence of plasmacytoid dendritic cells and type 1 interferon and the activation of interferon signaling pathway in lymphatic malformations.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  Nineteen lymphatic malformations with matching clinical data were compared to control tissue (normal skin and lymph node).
  
  
  METHODS
  Paraffin-embedded tissue was evaluated for plasmacytoid dendritic cells, type 1 interferon, and type 1 interferon signaling with immunohistochemistry and RNA in situ hybridization. Staining results were compared with controls and correlated with clinical data with descriptive statistics and Mann-Whitney tests.
  
  
  RESULTS
  Lymphatic malformations had increased staining for plasmacytoid dendritic cells, interferons alpha and beta, and phosphorylated signal transducer and activator of transcription 1 compared with controls (P < 0.05). Significantly increased interferon beta staining was present in recurrent lymphatic malformation tissue compared with nonrecurrent lymphatic malformations.
  
  
  CONCLUSIONS
  Lymphatic malformations have unusual ongoing local immune activation, possibly affecting recurrence.
authors.affiliation: Department of Pathology, University of Washington, Seattle, WA, USA.
authors.forename: Jo Nadine
authors.initials: JN
authors.lastname: Fleming
authors.forename: Sirkka Liisa
authors.initials: SL
authors.lastname: Hostikka
authors.forename: Eunice Y
authors.initials: EY
authors.lastname: Chen
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Schwartz
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Perkins
mesh_terms: D016022:Case-Control Studies; D003713:Dendritic Cells / Q000502:physiology*; D006801:Humans; D017403:In Situ Hybridization; D007370:Interferon Type I / Q000378:metabolism*; D007371:Interferon-gamma / Q000378:metabolism; D018191:Lymphangioma, Cystic / Q000276:immunology / Q000378:metabolism* / Q000473:pathology*; D050794:STAT1 Transcription Factor / Q000378:metabolism; D012878:Skin Neoplasms / Q000276:immunology / Q000378:metabolism* / Q000473:pathology*
chemical_list: D007370:Interferon Type I; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D007371:Interferon-gamma