Chlamydia trachomatis enhances the expression of matrix metalloproteinases in an in vitro model of the human fallopian tube infection

OBJECTIVE: The sequelae of sexually transmitted Chlarmydia trachomatis infection include fallopian tube scarring, which implies modification of the extracellular matrix. Our objective was to describe the production of two matrix metalloproteinases in response to chlamydial infection in vitro. STUDY DESIGN: Human fallopian tube organ cultures were infected with Chlamydia, and the production of matrix metalloproteinases was assessed by gelatin zymography, antigen capture enzyme-linked immunosorbent assay, immunohistochemistry, and in situ zymography. RESULTS: Significantly elevated levels of matrix metalloproteinase-2 and matrix metalloproteinase-9 were found in supernatants of infected segments. Immunohistochemistry and in situ zymography revealed that epithelial cells tended toward matrix metalloproteinase-2 production and that matrix metalloproteinase-9 exhibited a more diffuse stromal staining pattern. CONCLUSION: Matrix metalloproteinase-2 and matrix metalloproteinase-9 are expressed in vitro in response to chlamydial infection. Enhanced matrix metalloproteinase production in some individuals in response to infection may lead to tubal scarring through the increased turnover and subsequent repair of the extracellular matrix.