| Sign In to gain access to subscriptions and/or personal tools. |
DOI: 10.1177/107155760200900203 Association of Type II Apoptosis and 92-kDa Type IV Collagenase Expression in Human Amniochorion in Prematurely Ruptured Membranes With Tumor Necrosis Factor Receptor-1 Expression
Direction of Research and Electronics Microscopy Department, Instituto Nacional de Perinatologia, Mexico D.F., Mexico
Instituto Nacional de Perinatologia, Direccion de Investigacion, Montes Urales 800, Mexico, D.F., 11000, Mexico; felipe.vadillo{at}uia.mx Objective: We assessed the presence of tumor necrosis factor receptor-1 (TNF-R1), apoptosis, and simultaneous expression of 92-kDa collagenase type IV (MMP-9) in samples of human chorioamnion from women with premature rupture of membranes (PROM). Methods: Amniotic membranes from women who underwent normal labor, cesarean delivery, or had PROM at term were studied by immunohistochemistry for localization of TNF-R1 and R2. Transmission electron microscopy and DNA fragmentation analyses by agarose gel electrophoresis were performed to identify apoptosis characteristics. Zymography and in situ zymography were used to assess gelatinolytic activity. Results: We found that TNF-R1 was abundant in membranes from subjects who had normal labor and very abundant in those who had PROM. By contrast TNF-R2 was abundant only in membranes from subjects who had cesarean delivery. Gelatinolytic activity was associated with extracellular matrix rather than cells and was higher in extracts from fetal membranes from PROM and normal labor than in extracts obtained from cesarean deliveries. Transmission electron microscopy of fetal membranes from PROM revealed ultrastructural characteristics in amnion epithelium consistent with type II apoptosis. DNA laddering in agarose gel electrophoresis corroborated results from DNA fragmentation. Conclusion: During PROM the fetal membranes undergo type II apoptosis and extracellular matrix degradation in association with TNF-R1 expression.
Key Words: Apoptosis tumor necrosis factor receptor fetal membranes premature rupture of membranes metalloproteinases
|