title: Neutrophil elastase promotes proliferation of HaCaT cell line and transwell psoriasis organ culture model.
abstract: BACKGROUND
  Neutrophil elastase (NE) plays an important role in psoriasis. In this study we observed the effect of NE on the proliferation of HaCaT cells and transwell psoriasis organ culture model and investigated the mechanism.
  
  
  METHODS
  HaCaT cells were treated with various concentrations NE (0, 0.1, 1, 10, 100 IU/l). In addition, the cells were co-stimulated with 10 IU/l NE and 1 g/l sivelestat. Then, HaCaT cells proliferation and DNA synthesis were determined using methyl thiazolyl tetrazolium (MTT) and tritiated thymidine (3H-TdR) assay respectively. Cell cycle distribution was measured using fluorescence activated cell sorting (FACS). Subsequently, we established cultured transwell psoriasis organ model in vitro. Then, the cultured transwell psoriasis organ model was treated with 10 IU/l NE. Immunohistochemistry was employed to detect the expression levels of Ki67 and p53 in the cultured transwell psoriasis organ model.
  
  
  RESULTS
  MTT and 3H-TdR incorporation assay suggested NE could remarkably promote the proliferation and DNA synthesis of HaCaT cell in a dose-dependent manner. After NE treatment (10 IU/l) for 24 h, the cell fraction of HaCaT cell in G2 + S phase was increased significantly, whereas the cell fraction in G1 phase was reduced remarkably. Immunohistochemistry results revealed enhanced expression of both Ki67 and p53 genes in cultured transwell psoriasis organ model after NE treatment.
  
  
  CONCLUSIONS
  NE significantly promotes the proliferation of HaCaT cell. Meanwhile, it also up-regulates the expression levels of Ki67 and p53 in psoriasis lesion tissue, which plays an important role in the pathogenesis of psoriasis lesion.
authors.affiliation: Department of Dermatology, Southwest Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Xichuan
authors.initials: X
authors.lastname: Yang
authors.forename: Heng
authors.initials: H
authors.lastname: Yan
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Zhai
authors.forename: Fei
authors.initials: F
authors.lastname: Hao
authors.forename: Qingyi
authors.initials: Q
authors.lastname: Ye
authors.forename: Baiyu
authors.initials: B
authors.lastname: Zhong
mesh_terms: D002460:Cell Line; D049109:Cell Proliferation; D005998:Glycine / Q000031:analogs & derivatives / Q000494:pharmacology; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis / Q000378:metabolism; D019272:Leukocyte Elastase / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000502:physiology*; D009924:Organ Culture Techniques; D011565:Psoriasis / Q000201:enzymology* / Q000473:pathology; D013449:Sulfonamides / Q000494:pharmacology; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D019394:Ki-67 Antigen; D013449:Sulfonamides; D016159:Tumor Suppressor Protein p53; C069195:sivelestat; D019272:Leukocyte Elastase; D005998:Glycine