Levels of matrix metalloproteinase-9 and its inhibitor in guinea pig asthma model following ovalbumin challenge.
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 guinea pig asthma model following ovalbumin (OA) challenge. Twenty guinea pigs were divided into 2 groups: OA-challenged group were sensitized by intraperitoneal injection with OA and exposed to OA while the control group used saline in a similar manner. The positive level index (PLI), 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 levels of MMP-9 from OA-challenged group were significantly higher than those of controls. However, no significant difference of the TIMP-1 levels between the OA-challenged group and controls were found. MMP-9 was expressed strongly in both inflammatory and structural cells while TIMP-1 was expressed weakly in inflammatory cells and structural cells. Our results implied that MMP-9 may contribute to tissue remodeling in asthma and both structural and inflammatory cells within lung tissue are the main cellular sources of MMP-9. Excessive expression of MMP-9 in the early or acute stage of asthma may be associated with the initiation of bronchial injury and inflammatory cells accumulation.
Tang
Lan Fang
LF
The Children's Hospital of Zhejiang University School of Medicine, Hangzhou, China.
Du
Li Zhong
LZ
Zou
Chao Chun
CC
Gu
Wei Zhong
WZ
D000818:Animals; D001249:Asthma / Q000139:chemically induced / Q000276:immunology / Q000378:metabolism*; D004195:Disease Models, Animal; D005260:Female; D006168:Guinea Pigs; D007150:Immunohistochemistry; D008168:Lung / Q000276:immunology / Q000378:metabolism*; D008214:Lymphocytes / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis*; D010047:Ovalbumin / Q000276:immunology; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000096:biosynthesis*
D019715:Tissue Inhibitor of Metalloproteinase-1; D010047:Ovalbumin; D020780:Matrix Metalloproteinase 9