title: [Response of keloid fibroblasts to the effect of tumor necrosis factor-alpha(TNF-alpha)].
abstract: OBJECTIVE
  To investigate the biologic behavior of keloid fibroblasts and the pathogenesis of keloid.
  
  
  METHODS
  Human dermal fibroblasts cultured from normal skin and keloid were treated with tumor necrosis factor-alpha(TNF-alpha) for 48 hours at 10(3) U/ml and 10(4) U/ml. Collagen production by fibroblasts was assessed by 3H-proline in corporation into pepsin-resistant, precipitated extracellular collagenous protein.
  
  
  RESULTS
  TNF-alpha caused a concentration-dependent reduction in collagen production in normal dermal fibroblasts. Treatment with TNF-alpha at 10(3) U/ml significantly reduced the collagen synthesis in keloid fibroblasts (P < 0.01). However, the collagen synthesis in keloid fibroblasts did not further decreased after exposure to TNF-alpha at 10(4) U/ml.
  
  
  CONCLUSIONS
  Keloid fibroblasts may remain less sensitive to the inhibitory effects of TNF-alpha on collagen synthesis to a certain extent.
authors.affiliation: Department of Dermatology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: W
authors.initials: W
authors.lastname: He
authors.forename: R
authors.initials: R
authors.lastname: Liu
authors.forename: B
authors.initials: B
authors.lastname: Zhong
mesh_terms: D003094:Collagen / Q000096:biosynthesis*; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007627:Keloid / Q000209:etiology / Q000473:pathology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D003094:Collagen