Inflammatory cytokine (interleukins 1, 6 and 8 and tumor necrosis factor-alpha) release from cultured human fetal membranes in response to endotoxic lipopolysaccharide mirrors amniotic fluid concentrations.
OBJECTIVE
This study was conducted to quantitate and compare the amount of cytokines released from human fetal membranes in response to treatment with bacterial lipopolysaccharide and to compare this with amniotic fluid levels.


METHODS
Amniochorionic membranes were collected from women undergoing elective repeat cesarean section and showing no signs of infection- or pregnancy-related complications. Membranes were maintained in an organ explant system and stimulated with bacterial lipopolysaccharide for 24 hours. Media samples were collected and stored at -20 degrees C until cytokine levels were assayed by enzyme-linked immunosorbent assay.


RESULTS
Enzyme-linked immunosorbent assay results demonstrated that lipopolysaccharide stimulated production of interleukins 1, 6 and 8 and tumor necrosis factor-alpha by the fetal membranes in comparison with the control cultures. A greater release of interleukin-6 and interleukin-8 compared with interleukin-1 and tumor necrosis factor-alpha was noticed. The relationships between cytokine concentrations observed in culture mirror those seen in amniotic fluid.


CONCLUSIONS
Amniochorionic membranes can respond to an infectious process with increased secretion of interleukins 1, 6 and 8 and tumor necrosis factor-alpha. Cytokines produced from both amnion and chorion (interleukin-6 and interleukin-8) are released in greater quantities than those cytokines produced from chorion or amnion alone (interleukin-1 and tumor necrosis factor-alpha). These studies support a major role for amnion in infection-induced preterm labor.
Fortunato
S J
SJ
Maternal-Fetal Group, Women's Hospital at Centennial Medical Center, Nashville, Tennessee 37203, USA.
Menon
R P
RP
Swan
K F
KF
Menon
R
R
D000653:Amniotic Fluid / Q000378:metabolism*; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D016207:Cytokines / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005321:Extraembryonic Membranes / Q000378:metabolism*; D005260:Female; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D007700:Kinetics; D008070:Lipopolysaccharides / Q000494:pharmacology*; D011247:Pregnancy; D015203:Reproducibility of Results; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D017077:Culture Media, Conditioned; D016207:Cytokines; D007375:Interleukin-1; D015850:Interleukin-6; D016209:Interleukin-8; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha