title: Levels of matrix metalloproteinase-9 and its inhibitor in bronchoalveolar lavage cells of asthmatic children.
abstract: Our objective was to investigate the role of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and their cellular sources in childhood asthma. We used 12 controls and 16 asthmatic children. The levels of MMP-9 and TIMP-1 in bronchoalveolar lavage (BAL) cells of asthmatic children were measured immunocytochemically. The positive level index, defined as the percentage of positive-stained cells x average optical density, was used to assess the expressing levels of MMP-9 and TIMP-1. The percentages of eosinophils and mast cells in bronchoalveolar lavage fluid (BALF) of asthmatic children were increased. Levels of MMP-9 and TIMP-1 in BAL cell of asthmatic children were increased significantly at about 30- and 35-fold relative to the controls, respectively. These results suggest that both MMP-9 and TIMP-1 contribute to tissue remodeling. MMP-9, which mediates the degradation of extracellular matrix (ECM), is increased significantly in the early or acute stage and may play a role in ECM degeneration. Excessive TIMP-1 may be synthesized following MMP-9 production when the body tries to repair the damage, which results in excessive deposition of ECM component.
authors.affiliation: The Children's Hospital of Zhejiang University School of Medicine, Hangzhou, China.
authors.forename: Lan Fang
authors.initials: LF
authors.lastname: Tang
authors.forename: Li Zhong
authors.initials: LZ
authors.lastname: Du
authors.forename: Zhi Min
authors.initials: ZM
authors.lastname: Chen
authors.forename: Chao Chun
authors.initials: CC
authors.lastname: Zou
mesh_terms: D001249:Asthma / Q000378:metabolism* / Q000473:pathology*; D018893:Bronchoalveolar Lavage; D016022:Case-Control Studies; D002452:Cell Count; D002675:Child, Preschool; D004804:Eosinophils / Q000737:chemistry / Q000473:pathology; D005109:Extracellular Matrix / Q000737:chemistry / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D008297:Male; D008407:Mast Cells / Q000737:chemistry / Q000473:pathology; D020780:Matrix Metalloproteinase 9 / Q000032:analysis* / Q000378:metabolism*; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000032:analysis* / Q000378:metabolism*
chemical_list: D019715:Tissue Inhibitor of Metalloproteinase-1; D020780:Matrix Metalloproteinase 9