title: Effect of Pseudomonas aeruginosa on the expressions of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in the airway of bronchiectasis patients.
abstract: OBJECTIVE
  To study the expressions of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the airway of bronchiectasis (BE) patients, and evaluate the effect of pseudomonas aeruginosa (PAE) on the expression of TIMP-1 and MMP-9.
  
  
  METHODS
  In this case-control study, subjects were divided into BE group and control group, and the BE group was further divided into PAE group and other bacteria group based on the culture results of bronchoalveolar lavage fluid (BALF). BALF was obtained by bronchoscopy, the expressions of MMP-9 and TIMP-1 were determined by ELISA, then the ratio of TIMP-1/MMP-9 was calculated. Furthermore, the tissue of bronchic endomembrane was obtained by transbronchial biopsy and the expressions of MMP-9 and TIMP-1 were determined using immunohistochemical method.
  
  
  RESULTS
  The levels of MMP-9 in the BALF of PAE group and other bacteria group were significantly higher than that in control group (P=0.0000 both), and the expressions of MMP-9 in bronchic endomembrane of PAE group and other bacteria group were also significantly higher (P=0.0421 and 0.0003, respectively). The level of TIMP-1 in BALF of PAE group was significantly lower than that in other bacteria group (P=0.0324). The ratio of TIMP-1/MMP-9 in BALF of BE group was significantly lower than that in control group(P=0.0000), and this ratio of PAE group was significantly lower than those in both other bacteria group and control group (P=0.0026 and 0.0000, respectively).
  
  
  CONCLUSIONS
  PAE infection in BE patients can suppress the expression of TIMP-1 and stimulate the expression of MMP-9, and thus make the disease even worse.
authors.affiliation: Department of Respiratory Medicine, Tongde Hospital of Zhejiang Province, Hangzhou, China. jinqian0504@hotmail.com
authors.forename: Qian
authors.initials: Q
authors.lastname: Jin
authors.forename: Fei-hua
authors.initials: FH
authors.lastname: Huang
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhou
authors.forename: Ying-qing
authors.initials: YQ
authors.lastname: Zhang
authors.forename: Xiu-juan
authors.initials: XJ
authors.lastname: Chai
mesh_terms: D000328:Adult; D001980:Bronchi / Q000378:metabolism / Q000382:microbiology; D001987:Bronchiectasis / Q000378:metabolism*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D008875:Middle Aged; D011550:Pseudomonas aeruginosa; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism*
chemical_list: C560822:TIMP1 protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9