title: Soluble ST2 in the fetal inflammatory response syndrome: in vivo evidence of activation of the anti-inflammatory limb of the immune response.
abstract: OBJECTIVE
  Inflammation is a mechanism of host response to infection, which can be harmful when inappropriately modulated. Soluble ST2 (sST2) is a decoy receptor of interleukin (IL)-33, and this complex modulates the balance in the Th1/Th2 immune response. Moreover, sST2 inhibits the production of pro-inflammatory cytokines in cooperation with an anti-inflammatory cytokine, IL-10. The objectives of this study were to: (1) determine whether umbilical cord plasma sST2 concentration differs between preterm neonates with and without funisitis and between those with and without the fetal inflammatory response syndrome (FIRS); and (2) evaluate the relationship between sST2 and IL-10 among neonates with funisitis and/or FIRS.
  
  
  METHODS
  Umbilical cord plasma was collected from neonates delivered prematurely due to preterm labor or preterm prelabor rupture of membranes with (n = 36), and without funisitis (n = 30). FIRS (umbilical cord IL-6 concentration ≥ 17.5 pg/mL) was identified in 29 neonates. Plasma sST2 and IL-10 concentrations were determined by enzyme linked immune sorbent assay.
  
  
  RESULTS
  The median umbilical cord plasma sST2 concentration was 6.7-fold higher in neonates with FIRS than in those without FIRS (median 44.6 ng/mL, interquartile range (IQR) 13.8-80.3 ng/mL versus median 6.7 ng/mL, IQR 5.6-20.1 ng/mL; p < 0.0001). Similarly, the median umbilical cord plasma sST2 concentration was 2.7-fold higher in neonates with funisitis than in those without funisitis (median 19.1 ng/mL; IQR 7.1-75.0 ng/mL versus median 7.2 ng/mL; IQR 5.9-23.1 ng/mL; p = 0.008). There was a strong positive correlation between sST2 and IL-10 in neonates with funisitis and/or FIRS (Spearman's Rho = 0.7, p < 0.0001).
  
  
  CONCLUSIONS
  FIRS and funisitis are associated with an elevation of umbilical cord plasma concentrations of soluble ST2. This protein represents an important mediator of the immune response in neonates diagnosed with FIRS by promoting an anti-inflammatory effect in association with IL-10.
authors.affiliation: Perinatology Research Branch, NICHD/NIH/DHHS, Bethesda, MD and Detroit, MI 48201, USA.
authors.forename: Tamara
authors.initials: T
authors.lastname: Stampalija
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Korzeniewski
authors.forename: Piya
authors.initials: P
authors.lastname: Chaemsaithong
authors.forename: Jezid
authors.initials: J
authors.lastname: Miranda
authors.forename: Lami
authors.initials: L
authors.lastname: Yeo
authors.forename: Zhong
authors.initials: Z
authors.lastname: Dong
authors.forename: Sonia S
authors.initials: SS
authors.lastname: Hassan
authors.forename: Tinnakorn
authors.initials: T
authors.lastname: Chaiworapongsa
mesh_terms: D000328:Adult; D002821:Chorioamnionitis / Q000097:blood* / Q000276:immunology; D003430:Cross-Sectional Studies; D005260:Female; D005312:Fetal Blood / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood* / Q000276:immunology; D007249:Inflammation / Q000097:blood / Q000378:metabolism / Q000473:pathology; D000072179:Interleukin-1 Receptor-Like 1 Protein; D016753:Interleukin-10 / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood; D011247:Pregnancy; D011956:Receptors, Cell Surface / Q000097:blood*; D012189:Retrospective Studies; D018746:Systemic Inflammatory Response Syndrome / Q000097:blood* / Q000473:pathology*; D055815:Young Adult
chemical_list: C508609:IL10 protein, human; C079241:IL1RL1 protein, human; C508600:IL6 protein, human; D000072179:Interleukin-1 Receptor-Like 1 Protein; D015850:Interleukin-6; D011956:Receptors, Cell Surface; D016753:Interleukin-10