title: Analysis of perforin expression in peripheral blood and lesions in severe and mild psoriasis.
abstract: BACKGROUND
  Perforin is a membrane-disrupting protein that allows the entry of granzymes into a target cell inducing degradation of target substances in the cytoplasm and nucleus thus leading to programmed cell death or apoptosis. Recent work demonstrated a possible involvement of perforin mediated cytotoxicity in immunopathogenesis of psoriasis.
  
  
  OBJECTIVE
  To investigate a difference in systemic (peripheral blood) and local (lesions) expression and distribution of perforin in psoriatic patients with severe and mild disease.
  
  
  METHODS
  Flow cytometry was used for simultaneous detection of intracellular (perforin) and cell surface antigens in peripheral blood lymphocytes. The expression of perforin in skin lesions was evaluated by immunohistochemistry.
  
  
  RESULTS
  Significant increase of perforin expression in T lymphocytes, especially cytotoxic CD8+ cells was found in severe psoriasis compared to mild disease (p<0.01 and p<0.05, respectively). There was also an increase of CD56+P+ NK cells (p<0.05) in severe compared to mild psoriasis. The psoriatic plaque of both, severe and mild disease were abundant with perforin showing no significant difference on local level.
  
  
  CONCLUSIONS
  Based on our results we suggest the association between perforin expression and disease severity.
authors.affiliation: Department of Dermatovenerology, Clinical Hospital Centre Rijeka, University of Rijeka, Kresimirova 42, HR-51000, Rijeka, Croatia. larisaprpic@yahoo.com
authors.forename: Larisa
authors.initials: L
authors.lastname: Prpić Massari
authors.forename: Marija
authors.initials: M
authors.lastname: Kastelan
authors.forename: Gordana
authors.initials: G
authors.lastname: Laskarin
authors.forename: Gordana
authors.initials: G
authors.lastname: Zamolo
authors.forename: Drazen
authors.initials: D
authors.lastname: Massari
authors.forename: Daniel
authors.initials: D
authors.lastname: Rukavina
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007694:Killer Cells, Natural / Q000378:metabolism*; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood* / Q000378:metabolism; D008875:Middle Aged; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins / Q000097:blood* / Q000378:metabolism; D011565:Psoriasis / Q000097:blood* / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000378:metabolism*
chemical_list: D008562:Membrane Glycoproteins; D052899:Pore Forming Cytotoxic Proteins; D054353:Perforin