title: Eosinophil extracellular DNA traps in skin diseases.
abstract: BACKGROUND
  In the skin, eosinophils are found in a broad spectrum of diseases, including infectious diseases.
  
  
  OBJECTIVE
  In this study, we investigated whether eosinophil extracellular traps, structures containing DNA in association with eosinophil granule proteins able to bind and kill bacteria, are present in the skin under various pathologic conditions.
  
  
  METHODS
  Immunofluorescence staining was performed on sections of paraformaldehyde-fixed and paraffin-embedded skin biopsy tissues of 25 different eosinophilic skin diseases by using propidium iodide and an antibody to eosinophil cationic protein. Slides were evaluated by laser scanning microscopy.
  
  
  RESULTS
  Eosinophils releasing DNA together with eosinophil cationic protein were detected in infectious skin diseases such as ectoparasitosis and larva migrans. Further, we observed the extracellular DNA structures in allergic/reactive diseases (Wells syndrome, hypereosinophilic syndrome, positive reaction of atopy patch test, allergic contact dermatitis, drug hypersensitivity) and in autoimmune diseases (bullous pemphigoid, pemphigus foliaceus, dermatitis herpetiformis). The average number of eosinophils releasing DNA in the skin was usually below 10%, although in Wells syndrome the proportion was up to 30%. In areas with clusters of eosinophils, up to 50% of the eosinophils were seen to generate eosinophil extracellular traps.
  
  
  CONCLUSIONS
  Eosinophil extracellular traps are seen in both infectious and noninfectious inflammatory skin diseases and are particularly common in Wells syndrome.
authors.affiliation: Department of Dermatology, Inselspital, Bern University Hospital, Bern, Switzerland. dagmar.simon@insel.ch
authors.forename: Dagmar
authors.initials: D
authors.lastname: Simon
authors.forename: Susanne
authors.initials: S
authors.lastname: Hoesli
authors.forename: Nina
authors.initials: N
authors.lastname: Roth
authors.forename: Simon
authors.initials: S
authors.lastname: Staedler
authors.forename: Shida
authors.initials: S
authors.lastname: Yousefi
authors.forename: Hans-Uwe
authors.initials: HU
authors.lastname: Simon
mesh_terms: D004247:DNA / Q000276:immunology* / Q000378:metabolism; D047091:Eosinophil Granule Proteins / Q000378:metabolism; D004804:Eosinophils / Q000276:immunology* / Q000378:metabolism; D005109:Extracellular Matrix / Q000276:immunology* / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006801:Humans; D018613:Microscopy, Confocal; D012871:Skin Diseases / Q000276:immunology* / Q000378:metabolism
chemical_list: D047091:Eosinophil Granule Proteins; D004247:DNA