title: Expression of MMP-9, MMP-10 and TNF-alpha and lack of epithelial MMP-1 and MMP-26 characterize pyoderma gangrenosum.
abstract: BACKGROUND
  Pyoderma gangrenosum (PG) is a non-infectious, autoimmune, chronic ulcer of the skin, often co-existing with inflammatory bowel disease (IBD). Matrix metalloproteinases (MMPs) have been implicated as mediators of tissue destruction in chronic cutaneous and intestinal wounds.
  
  
  METHODS
  Twenty-four skin biopsies with clinically and histologically confirmed PG and acute wounds were immunostained for MMP-1, -7, -8, -9, -10 and -26; tissue inhibitors of matrix metalloproteinase (TIMP)-1 and -3 and tumor necrosis factor-alpha (TNF-alpha).
  
  
  RESULTS
  MMP-1 was generally expressed by keratinocytes distal from the wound edge, whereas MMP-10 was detected abundantly in the epithelium. MMP-26 was positive in 42% at the migratory front. Abundant stromal expression was evident for MMP-1, -9 and -10, TIMP-1 and -3 and TNF-alpha. In acute wounds, stromal MMP-1, -9 and -10 and TNF-alpha were sparse.
  
  
  CONCLUSIONS
  Unlike in normally healing cutaneous wounds, MMP-1 and -26 were detected bordering the wound in only a minority of PGs and their lack may thus retard epithelial repair. Particularly, MMP-9 and -10 and TNF-alpha would be suitable therapeutic targets as they may contribute to the degradation of provisional matrices needed for migration in healing wounds. The presence of MMP-1, -9, -10 and -26 in both PG and IBD ulcers may suggest a similar pathogenesis for cutaneous and mucosal inflammation.
authors.affiliation: Department of Dermatology, Helsinki University Central Hospital, and University of Helsinki, Helsinki, Finland.
authors.forename: Ville
authors.initials: V
authors.lastname: Bister
authors.forename: Laura
authors.initials: L
authors.lastname: Mäkitalo
authors.forename: Leila
authors.initials: L
authors.lastname: Jeskanen
authors.forename: Ulpu
authors.initials: U
authors.lastname: Saarialho-Kere
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000096:biosynthesis; D053506:Matrix Metalloproteinase 10 / Q000096:biosynthesis; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis; D020782:Matrix Metalloproteinases / Q000096:biosynthesis*; D053505:Matrix Metalloproteinases, Secreted / Q000096:biosynthesis; D008875:Middle Aged; D017511:Pyoderma Gangrenosum / Q000378:metabolism* / Q000473:pathology; D019714:Tissue Inhibitor of Metalloproteinases / Q000096:biosynthesis; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D019714:Tissue Inhibitor of Metalloproteinases; D014409:Tumor Necrosis Factor-alpha; C410599:MMP26 protein, human; D020782:Matrix Metalloproteinases; D053505:Matrix Metalloproteinases, Secreted; D053506:Matrix Metalloproteinase 10; D020780:Matrix Metalloproteinase 9; D020781:Matrix Metalloproteinase 1