title: Expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases during normal human pulmonary development.
abstract: OBJECTIVE
  Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are thought to be involved in lung development because they play an important role in the turnover of the extracellular matrix. Although limited data on MMP and TIMP expression are available from animal studies during prenatal pulmonary development, little is known about their expression during human fetal lung development. The aim of this study was to investigate the expression of MMP-1, -2, -9, TIMP-1, -2 and -3 in human fetal lungs from 9 to 42 weeks of gestation.
  
  
  RESULTS
  Forty-five normal human fetal lung samples were analysed by immunohistochemistry. MMP-1, -9, TIMP-1, -2 and -3, but not MMP-2, were expressed in the epithelium at all gestational ages. The endothelium of all vessels and the arterial smooth muscle cells expressed MMP-1, -2, -9, TIMP-2 and -3, but not TIMP-1, at all developmental stages.
  
  
  CONCLUSIONS
  The extensive distribution of MMPs and TIMPs throughout all stages of human lung development suggests that they play a significant role in the remodelling that occurs in the interstitium and epithelial basement membrane during lung development and in pulmonary vascular development. These data will serve as a base line for comparison with neonatal lung pathology, including pulmonary hypertension.
authors.affiliation: Department of Paediatric Surgery, Erasmus MC-Sophia, Rotterdam, the Netherlands.
authors.forename: K
authors.initials: K
authors.lastname: Masumoto
authors.forename: J D
authors.initials: JD
authors.lastname: de Rooij
authors.forename: S
authors.initials: S
authors.lastname: Suita
authors.forename: R
authors.initials: R
authors.lastname: Rottier
authors.forename: D
authors.initials: D
authors.lastname: Tibboel
authors.forename: R R
authors.initials: RR
authors.lastname: de Krijger
mesh_terms: D005333:Fetus; D006801:Humans; D007150:Immunohistochemistry; D008168:Lung / Q000196:embryology* / Q000378:metabolism*; D020782:Matrix Metalloproteinases / Q000096:biosynthesis*; D019714:Tissue Inhibitor of Metalloproteinases / Q000096:biosynthesis*
chemical_list: D019714:Tissue Inhibitor of Metalloproteinases; D020782:Matrix Metalloproteinases