title: Differential expression of immune system-related components in midtrimester amniotic fluid from singleton and twin pregnancies.
abstract: OBJECTIVE
  We investigated differences between singleton and twin gestations in immune mediators in midtrimester amniotic fluid.
  
  
  METHODS
  Amniotic fluid from 252 singleton and 46 twin gestations were tested by enzyme-linked immunosorbent assay for interleukin-1beta, interleukin-1 receptor antagonist, interleukin-4, tumor necrosis factor-alpha, nitric oxide, Clara cell protein 16, leptin, and the 70-kDa heat shock protein. A subset of amniotic fluid was also tested for leukemia inhibitory factor, angiogenin, and migration inhibitory factor-related protein 8 and migration inhibitory factor-related protein 14. Data were analyzed by the Mann-Whitney U test and Spearman rank correlation.
  
  
  RESULTS
  Median concentrations of interleukin-1beta, tumor necrosis factor-alpha, interleukin-4, Clara cell protein 16, leptin, and angiogenin were increased in amniotic fluid from twins; median levels of the 70-kDa heat shock protein, leukemia inhibitory factor, migration inhibitory factor-related protein 8, and migration inhibitory factor-related protein 14 were highest in amniotic fluid from singletons (P < .001).
  
  
  CONCLUSIONS
  Elevated levels of immune activators may contribute to the increased rate of preterm premature rupture of membranes and spontaneous preterm birth in twin populations.
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Weill Medical College of Cornell University, New York, NY 10021, USA. scperni@yahoo.com
authors.forename: Sriram C
authors.initials: SC
authors.lastname: Perni
authors.forename: Robin B
authors.initials: RB
authors.lastname: Kalish
authors.forename: J Milton
authors.initials: JM
authors.lastname: Hutson
authors.forename: Emre
authors.initials: E
authors.lastname: Karasahin
authors.forename: Ann Marie
authors.initials: AM
authors.lastname: Bongiovanni
authors.forename: Vladimir
authors.initials: V
authors.lastname: Ratushny
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Chasen
authors.forename: Steven S
authors.initials: SS
authors.lastname: Witkin
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000737:chemistry* / Q000276:immunology; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000276:immunology; D018840:HSP70 Heat-Shock Proteins / Q000032:analysis; D006801:Humans; D007249:Inflammation / Q000276:immunology; D007375:Interleukin-1 / Q000032:analysis; D007378:Interleukins / Q000032:analysis*; D020738:Leptin / Q000032:analysis; D008263:Macrophage Migration-Inhibitory Factors / Q000032:analysis; D010741:Phospholipases A / Q000037:antagonists & inhibitors; D011247:Pregnancy / Q000276:immunology*; D011262:Pregnancy Trimester, Second; D011272:Pregnancy, Multiple / Q000276:immunology*; D014427:Twins; D014598:Uteroglobin / Q000276:immunology
chemical_list: D018840:HSP70 Heat-Shock Proteins; D007375:Interleukin-1; D007378:Interleukins; D020738:Leptin; D008263:Macrophage Migration-Inhibitory Factors; C556389:SCGB1A1 protein, human; D014598:Uteroglobin; D010741:Phospholipases A