title: Normative levels of Interleukin 16 in umbilical cord blood.
abstract: OBJECTIVE
  The need for early and accurate prediction of outcome in hypoxic-ischaemic encephalopathy (HIE) remains critical. We have previously demonstrated that Interleukin 16 (IL-16) is raised in the umbilical cord blood (UCB) of infants with moderate and severe HIE and has the potential to be developed as a predictive biomarker. Normal reference ranges for IL-16 in UCB have not been previously described. The aim of this study was to determine normative levels of IL-16 in full term neonates using UCB following uncomplicated deliveries and to examine the effect of labour on cord IL-16 values.
  
  
  METHODS
  Full term infants were recruited as part of an ongoing birth cohort study, the Cork BASELINE Birth Cohort Study. All had UCB drawn and bio-banked at -80°C, within 3hours of birth. Samples for this experiment were chosen from this population based cohort study to represent uncomplicated pre-labour caesarean sections and spontaneous vaginal deliveries. Analysis was performed on plasma EDTA, using ELISA Quantikine® (R&D Systems, Europe).
  
  
  RESULTS
  Samples were analysed from 48 infants with two modes of delivery; spontaneous vaginal delivery (n=12 male, n=12 female) and elective caesarean section (n=12 male, n=12 female). The range of all samples was normally distributed between 87.0 and 114.6pg/ml. Overall mean (SD) for IL-16 was 102.9 (21.5) pg/ml. Levels were not affected by spontaneous vaginal delivery or gender.
  
  
  CONCLUSIONS
  For the first time we have described the expected range of cord plasma IL-16 levels in healthy term infants following pre-labour and post-labour delivery.
authors.affiliation: Neonatal Brain Research Group, Department of Paediatrics and Child Health, Cork University Maternity Hospital, Wilton, Cork, Ireland. Electronic address: n.denihan@ucc.ie.
authors.forename: N M
authors.initials: NM
authors.lastname: Denihan
authors.forename: Am
authors.initials: A
authors.lastname: Looney
authors.forename: G B
authors.initials: GB
authors.lastname: Boylan
authors.forename: B H
authors.initials: BH
authors.lastname: Walsh
authors.forename: D M
authors.initials: DM
authors.lastname: Murray
mesh_terms: D002585:Cesarean Section; D015331:Cohort Studies; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D006801:Humans; D007231:Infant, Newborn; D019410:Interleukin-16 / Q000097:blood*; D007743:Labor, Obstetric / Q000097:blood; D008297:Male; D011247:Pregnancy; D012016:Reference Values
chemical_list: D019410:Interleukin-16
keywords: Cytokines; ELISA; Elective caesarean section; Hypoxic–ischaemic encephalopathy; Interleukin 16; Pregnancy; Umbilical cord blood; Vaginal delivery