| Roles of Matrix Metalloproteinases on Intracellular Staphylococcus aureus Growth in Bronchial Epithelial Cell. |
|
Bo Ram Min, Young Mi Lee, Jae Seok Park, Won Il Choi, Kun Young Kwon |
1Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea. wichoi@dsmc.or.kr
2Department of Pathology, Keimyung University School of Medicine, Daegu, Korea. |
|
|
| Abstract |
BACKGROUND
Staphylococcus aureus frequently colonizes and infects hospitalized patients. Respiratory infections with Staphylococcus aureus are common in patients with compromised airway defenses. However the mechanisms of S. aureus invasion from colonization to the epithelium are unclear. Cell invasion by S. aureus would require destruction of the extracellular matrix, which is believed to be the result of increased matrix metalloproteinases (MMP) activity. METHODS: In this study, respiratory epithelial cells were infected with S. aureus. After removing the extracellular bacteria by washing, the internalized bacteria in the cells were assessed by counting the colonized forming units (CFUs). The cell adhesion proteins, dysadherin and E-cadherin, were evaluated by Western blotting. The MMPs in the bacterial invasion were evaluated by pretreating the cells with GM6001, a MMP inhibitor. RESULTS: The internalization of S. aureus was found to be both time and dose dependent, and the increase in MMP 2 and 9 activity was also dependent on the incubation time and the initial amount of bacterial inoculation. The invasion of S. aureus was attenuated by GM6001 after 12 hours incubation with a multiply of infection (MOI)=50. The expression of dysadherin, a membrane protein, was increased in a time and dose dependent manner, while the expression of E-cadherin was decreased. CONCLUSION: MMPs may mediate the invasion of S. aureus into epithelial cells. |
| Key Words:
Staphylococcus aureus, Epithelial cell, Matrix metalloproteinases |
|
PDF Links
Full text via DOI
Download Citation
