title: Differential release of interleukin-6 from human gestational tissues in association with labour and in vitro endotoxin treatment.
abstract: In this study, we quantified interleukin-6 (IL-6) concentrations in amniotic fluid at term and preterm labour, and determined the gestational tissue source of IL-6. In addition, aspects of the regulatory mechanisms involved in IL-6 release at the time of term labour and in response to bacterial endotoxin, lipopolysaccharide (LPS), have been established. IL-6 concentrations were 2-fold higher in amniotic fluid collected at term compared with preterm gestation, with an additional 2-fold increase in association with term labour. IL-6 was released from all choriodecidual and placental explants but was detected in only 33% of amniotic explant cultures of tissues obtained before labour onset. In contrast, IL-6 was detected in all amniotic, choriodecidual and placental cultures of tissues obtained after term labour onset and delivery, and the mean IL-6 release was significantly higher than that measured in explant cultures of both amniotic (80-fold increase, P < 0.0001) and choriodecidual (3-fold increase, P < 0.02) but not placental explants taken at the time of elective Caesarean section at term before labour onset. LPS significantly (P < 0.05) increased the release of IL-6 from human choriodecidual and placental explants but not amniotic explants, in a time- and dose-dependent manner. IL-6 is a physiological constituent of amniotic fluid and its production by gestational tissues is differentially regulated by LPS and spontaneous labour onset and delivery.
authors.affiliation: Department of Perinatal Medicine, Royal Women's Hospital, Victoria, Australia.
authors.forename: N
authors.initials: N
authors.lastname: Laham
authors.forename: S P
authors.initials: SP
authors.lastname: Brennecke
authors.forename: K
authors.initials: K
authors.lastname: Bendtzen
authors.forename: G E
authors.initials: GE
authors.lastname: Rice
mesh_terms: D000653:Amniotic Fluid / Q000378:metabolism*; D002585:Cesarean Section; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli; D005321:Extraembryonic Membranes / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D015850:Interleukin-6 / Q000378:metabolism*; D007745:Labor Onset; D007743:Labor, Obstetric / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D010920:Placenta / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D013997:Time Factors
chemical_list: D015850:Interleukin-6; D008070:Lipopolysaccharides