The effect of transforming growth factor and interleukin-10 on interleukin-8 release by human amniochorion may regulate histologic chorioamnionitis.
OBJECTIVE
Amniochorion is a source of interleukin-8 during infection and inflammation. In this study we investigate the role of 2 immunoinhibitory cytokines, transforming growth factor and interleukin-10, in regulating interleukin-8 production from human fetal membranes and define their mechanism of regulation.


METHODS
Amniochorion was placed in an organ explant system for 72 hours. Tissues were stimulated with lipopolysaccharide (50 ng/mL), lipopolysaccharide plus transforming growth factor-beta (50/50, 50/100), transforming growth factor-beta (50 and 100 ng/mL), lipopolysaccharide plus interleukin-10 (50/50 and 50/100), and interleukin-10 (50 and 100 ng/mL) in culture. Tissue and media samples were frozen until quantitation of interleukin-8 messenger ribonucleic acid and protein. Quantitation of messenger ribonucleic acid was performed by quantitative competitive polymerase chain reaction and protein by enzyme-linked immunoassay, respectively.


RESULTS
Lipopolysaccharide-stimulated tissues produced approximately 6 x 10(6) molecules per microliter of interleukin-8 messenger ribonucleic acid compared with 6 x 10(3) molecules per microliter in controls. Transforming growth factor-beta alone and lipopolysaccharide plus transforming growth factor-beta stimulation produced 6 x 10(5) and 6 x 10(4) molecules of interleukin-8 messenger ribonucleic acid per microliter, respectively. Tissues stimulated with lipopolysaccharide plus 50 ng/mL interleukin-10 produced approximately 600 molecules per microliter of interleukin-8 messenger ribonucleic acid, whereas no amplifiable messenger ribonucleic acid was detected in tissues treated with lipopolysaccharide plus 100 ng/mL interleukin-10. Tissues treated with interleukin-10 alone produced 6 x 10(3) molecules of messenger ribonucleic acid, similar to control levels. Enzyme-linked immunosorbent assay data showed similar levels of interleukin-8 peptide release from lipopolysaccharide and lipopolysaccharide plus transforming growth factor-beta-treated fetal membranes. A dose-dependent decrease in interleukin-8 peptide release was seen in tissues treated with lipopolysaccharide plus interleukin-10, whereas stimulation with transforming growth factor or interleukin-10 alone resulted in interleukin-8 peptide release similar to that of control levels.


CONCLUSIONS
Transforming growth factor-beta seems to have no effect on interleukin-8 protein production in the presence of an infectious agent; however, a drop in messenger ribonucleic acid levels was observed. Interleukin-10 in the presence of lipopolysaccharide showed down-regulation of interleukin-8 messenger ribonucleic acid expression and peptide production. These data suggest that fetal membrane interleukin-8 production can be controlled by interleukin-10 during an infectious process.
Fortunato
S J
SJ
Maternal-Fetal Group and the Perinatal Research Center of the Women's Health Research and Education Foundation, Women's Hospital at Centennial Medical Center, Nashville, Tennessee 37203, USA.
Menon
R
R
Lombardi
S J
SJ
D000650:Amnion / Q000187:drug effects / Q000378:metabolism*; D002821:Chorioamnionitis / Q000378:metabolism*; D002823:Chorion / Q000187:drug effects / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D016753:Interleukin-10 / Q000494:pharmacology*; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D009924:Organ Culture Techniques; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D014158:Transcription, Genetic; D015291:Transforming Growth Factors / Q000494:pharmacology*
D016209:Interleukin-8; D008070:Lipopolysaccharides; D016753:Interleukin-10; D015291:Transforming Growth Factors