title: [Connective tissue degradation in human amniochorion after stimulation with choriodecidual lymphocytes infected with group B streptococci].
abstract: OBJECTIVE
  To identify whether soluble products from choriodecidual blood cells stimulated with group B streptococci (GBS) induce connective tissue degradation in human amniochorion.
  
  
  METHODS
  Blood samples from choriodecidual compartment were collected by direct aspiration from placental cotyledons draining blood and represent local circulating cells. Samples were divided into two aliquots: one was stimulated with GBS (1 X 10(6) CFU/mL) and the other was kept free of bacteria as negative control. After overnight incubation, plasmas were separated. Chorioamnion explants were stimulated with 10% plasma for 12h at 37 degrees C in 5% CO2. MMP-9 proteolytic activity was measured in the supernatants by gelatin-zymography and IL-1beta and TNF-alpha were quantified by ELISA. Distribution of the collagenous fibrils in explants was examined by electron microscopy.
  
  
  METHODS
  three independent experiments on duplicate were carried out and the statistical significance of experimental differences between groups was assessed with ANOVA test.
  
  
  RESULTS
  MMP-9, IL-1beta and TNF-alpha production was significantly higher in supernatants from explants co-cultured with choriodecidual plasma from blood previously infected with GBS, compared with control plasma. Accompanying extensive changes of connective tissue arrangement confirm induction of extracellular matrix degradation.
  
  
  CONCLUSIONS
  Choriodecidual plasma from blood stimulated with GBS is enriched with biochemical signals that enhance the MMP-9, IL-1alpha and TNF-beta production by amniochorion. These findings suggest that local circulating cells are capable to act in response to GBS choriodecidual infection through extracellular matrix degradation and the consequent rupture of membranes.
authors.affiliation: Instituto Nacional de Perinatología, SSA, México, DF.
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Estrada Gutiérrez
authors.forename: Raquel
authors.initials: R
authors.lastname: Reyes Trejo
authors.forename: Rolando
authors.initials: R
authors.lastname: Maida Claros
authors.forename: Jorge
authors.initials: J
authors.lastname: Beltrán Montoya
authors.forename: Felipe
authors.initials: F
authors.lastname: Vadillo Ortega
mesh_terms: D008214:Lymphocytes / Q000382:microbiology*; D013292:Streptococcus agalactiae