Expression of MMP-9 and TIMP-1 in the Nasal Mucosa of Allergic Rhinitis

Lee, Heung Man; Choi, Jin Ho; Choi, Choong Sik; Hwang, Soon Jae; Lee, Sang Hag

Abstract

BACKGROUND AND OBJECTIVES: Allergic rhinitis is characterized by airway structural changes, including inflammation and basement thickening. An imbalance between matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) is thought to play a critical role in the synthesis or degradation of the extracellular matrix of the airway architecture. To elucidate the mechanism of remodeling in allergic rhinitis, we investigated the expressions of MMP-9 and TIMP-1 in the nasal mucosa of allergic rhinitis patients and the control subjects. We also compared the number of infiltrating inflammatory cells (eosinophils) and the immunostained areas of MMP-9 and TIMP-1.
MATERIALS AND METHODS
Nasal biopsy specimens were obtained from 20 subjects with allergic rhinitis and 20 healthy control subjects, and the extent of staining by MMP-9 and TIMP-1 was estimated by using immunohistochemicd staining. Using a computer assisted image analysis system, we quantified the expressions of MMP-9 and TIMP-1, and the number of inflammatory cells was also determined.
RESULTS
Expressions of MMP-9 and TIMP-1 were observed in the nasal mucosa of epithelial cells and infiltrating inflammatory cells. The extent of immunostained areas of MMP-9 was signi6cantly greater than that of TIMP-1 in the allergic rhinitis patients. A significant correlation was found between the number of eosinophils and the extent of MMP-9 immunostained area.
CONCLUSION
The increased expression of MMP-9 in the allergic nasal mucosa suggests that MMP-9 secreted from the infiltrating inflammatory cells and the nasal epithelium causes tissue remodeling in the allergic nasal mucosa.