title: Clinical chorioamnionitis at term V: umbilical cord plasma cytokine profile in the context of a systemic maternal inflammatory response.
abstract: OBJECTIVE
  Microbial invasion of the fetus due to intra-amniotic infection can lead to a systemic inflammatory response characterized by elevated concentrations of cytokines in the umbilical cord plasma/serum. Clinical chorioamnionitis represents the maternal syndrome often associated with intra-amniotic infection, although other causes of this syndrome have been recently described. The objective of this study was to characterize the umbilical cord plasma cytokine profile in neonates born to mothers with clinical chorioamnionitis at term, according to the presence or absence of bacteria and/or intra-amniotic inflammation.
  
  
  METHODS
  A cross-sectional study was conducted, including patients with clinical chorioamnionitis at term (n=38; cases) and those with spontaneous term labor without clinical chorioamnionitis (n=77; controls). Women with clinical chorioamnionitis were classified according to the results of amniotic fluid culture, broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry (PCR/ESI-MS) and amniotic fluid interleukin (IL)-6 concentration into three groups: 1) no intra-amniotic inflammation; 2) intra-amniotic inflammation without detectable microorganisms; or 3) microbial-associated intra-amniotic inflammation. A fetal inflammatory response syndrome (FIRS) was defined as an umbilical cord plasma IL-6 concentration >11 pg/mL. The umbilical cord plasma concentrations of 29 cytokines were determined with sensitive and specific V-PLEX immunoassays. Nonparametric statistical methods were used for analysis, adjusting for a false discovery rate of 5%.
  
  
  RESULTS
  1) Neonates born to mothers with clinical chorioamnionitis at term (considered in toto) had significantly higher median umbilical cord plasma concentrations of IL-6, IL-12p70, IL-16, IL-13, IL-4, IL-10 and IL-8, but significantly lower interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF)-α concentrations than neonates born to mothers with spontaneous term labor without clinical chorioamnionitis; 2) neonates born to mothers with clinical chorioamnionitis at term but without intra-amniotic inflammation had higher concentrations of IL-6, IL-12p70, IL-13, IL-4, IL-5, and IL-8, but lower IFN-γ, than neonates not exposed to clinical chorioamnionitis, suggesting that maternal fever in the absence of intra-amniotic inflammation leads to a change in the fetal cytokine network; 3) there were significant, positive correlations between maternal and umbilical cord plasma IL-6 and IL-8 concentrations (IL-6: Spearman correlation=0.53; P<0.001; IL-8: Spearman correlation=0.42; P<0.001), consistent with placental transfer of cytokines; 4) an elevated fetal plasma IL-6 (>11 pg/mL), the diagnostic criterion for FIRS, was present in 21% of cases (8/38), and all these neonates were born to mothers with proven intra-amniotic infection; and 5) FIRS was associated with a high concentration of umbilical cord plasma IL-8, IL-10 and monocyte chemoattractant protein (MCP)-1.
  
  
  CONCLUSIONS
  Neonates born to mothers with clinical chorioamnionitis at term had higher concentrations of umbilical cord plasma cytokines than those born to mothers without clinical chorioamnionitis. Even neonates exposed to clinical chorioamnionitis but not to intra-amniotic inflammation had elevated concentrations of multiple cytokines, suggesting that intrapartum fever alters the fetal immune response.
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero
authors.forename: Piya
authors.initials: P
authors.lastname: Chaemsaithong
authors.forename: Nikolina
authors.initials: N
authors.lastname: Docheva
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Korzeniewski
authors.forename: Adi L
authors.initials: AL
authors.lastname: Tarca
authors.forename: Gaurav
authors.initials: G
authors.lastname: Bhatti
authors.forename: Zhonghui
authors.initials: Z
authors.lastname: Xu
authors.forename: Juan P
authors.initials: JP
authors.lastname: Kusanovic
authors.forename: Noppadol
authors.initials: N
authors.lastname: Chaiyasit
authors.forename: Zhong
authors.initials: Z
authors.lastname: Dong
authors.forename: Bo Hyun
authors.initials: BH
authors.lastname: Yoon
authors.forename: Sonia S
authors.initials: SS
authors.lastname: Hassan
authors.forename: Tinnakorn
authors.initials: T
authors.lastname: Chaiworapongsa
authors.forename: Lami
authors.initials: L
authors.lastname: Yeo
authors.forename: Yeon Mee
authors.initials: YM
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002821:Chorioamnionitis / Q000097:blood* / Q000175:diagnosis / Q000382:microbiology; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000097:blood*; D005260:Female; D005312:Fetal Blood / Q000276:immunology*; D006801:Humans; D007231:Infant, Newborn; D015850:Interleukin-6 / Q000097:blood; D008431:Maternal-Fetal Exchange / Q000276:immunology; D011247:Pregnancy; D018746:Systemic Inflammatory Response Syndrome / Q000097:blood / Q000276:immunology; D047929:Term Birth; D055815:Young Adult
chemical_list: D016207:Cytokines; C508600:IL6 protein, human; D015850:Interleukin-6