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Updated: Oct 10, 2026
A Mouse Model for Pathogen-induced Chronic Inflammation at Local and Systemic Sites
Published on: August 8, 2014
Membrane-type matrix metalloproteinases in mice intracorneally infected with Pseudomonas aeruginosa
1Departments of Immunology and Microbiology and. Pathology, Wayne State University School of Medicine, Detroit, Michigan, USA.
Purpose:
To establish the presence of membrane-type matrix metalloproteinases (MT-MMPs) in the cornea and their expression in naive and immunized mice intracorneally infected with Pseudomonas aeruginosa.
Methods:
Naive (unimmunized) and immunized C57BL/6J mice were infected with P. aeruginosa, and gene expression of MT-MMPs were detected by RT-PCR. Immunoblot analysis and immunostaining were also used to characterize the MT-MMP response in both sets of animals.
Results:
Expression of MT1-MMP, MT2-MMP, and MT3-MMP (MMP 14, 15, and 16) was detected by RT-PCR and immunoblot analysis. Of the three MT-MMPs detected, MT1-MMP exhibited the greatest expression at protein levels. In general, a bell-shaped curve was obtained for each of the MT-MMPs in naive mice, but all of them showed much less expression in the immunized mice. MT1-MMP was localized in the epithelial tissue of the cornea, whereas MT2-MMP and MT3-MMP were mainly found in the interface between the epithelium and substantia propria.
Conclusions:
MT1-MMP was detected and expressed to a greater extent in naive mice than MT2-MMP and MT3-MMP. Peak expression of all three MT-MMPs showed a good correlation with the overall inflammatory response.
Insights
Membrane-type matrix metalloproteinases (MT-MMPs) are present in the cornea. Their expression, particularly MT1-MMP, is higher in naive mice during Pseudomonas aeruginosa infection compared to immunized mice.
Area of Science:
- Ocular Microbiology
- Immunology
- Biochemistry
Background:
- Corneal infections, such as those caused by Pseudomonas aeruginosa, can lead to significant inflammation and tissue damage.
- Matrix metalloproteinases (MMPs) play a role in tissue remodeling and inflammation, but their specific involvement in corneal bacterial infections is not fully understood.
- Membrane-type matrix metalloproteinases (MT-MMPs) are a subclass of MMPs with unique functions in cell surface proteolysis and extracellular matrix degradation.
Purpose of the Study:
- To investigate the presence and expression of MT-MMPs in the cornea.
- To characterize the expression patterns of MT-MMPs in naive and immunized mice following intracorneal infection with Pseudomonas aeruginosa.
Main Methods:
- Gene expression analysis using RT-PCR to detect MT-MMP mRNA.
- Immunoblot analysis to quantify MT-MMP protein levels.
- Immunostaining to determine the cellular localization of MT-MMPs within the cornea.
Main Results:
- Expression of MT1-MMP, MT2-MMP, and MT3-MMP was detected in the cornea.
- MT1-MMP showed the highest protein expression among the studied MT-MMPs.
- Naive mice exhibited higher MT-MMP expression compared to immunized mice, with peak expression correlating with the inflammatory response.
Conclusions:
- MT1-MMP is significantly expressed in the cornea during Pseudomonas aeruginosa infection, particularly in naive animals.
- The expression levels of MT-MMPs are modulated by prior immunization.
- MT-MMP expression correlates with the host's inflammatory response to corneal infection.
