Levels of matrix metalloproteinase-9 and its inhibitor in bronchoalveolar lavage cells of asthmatic children.
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.
Tang
Lan Fang
LF
The Children's Hospital of Zhejiang University School of Medicine, Hangzhou, China.
Du
Li Zhong
LZ
Chen
Zhi Min
ZM
Zou
Chao Chun
CC
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*
D019715:Tissue Inhibitor of Metalloproteinase-1; D020780:Matrix Metalloproteinase 9