title: Differential expression of antimicrobial polypeptides in cord blood samples of preterm and term infants.
abstract: OBJECTIVE
  To determine levels of antimicrobial polypeptides (AMP) in cord blood of term and preterm neonates and to investigate influencing factors.
  
  
  METHODS
  In a single-centre study, n = 139 preterm infants and n = 36 term infants were included. AMP levels were analysed in supernatants of whole cord blood cultures with a standardised concentration of 5 × 10(6) white blood cells/mL via enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  Lactoferrin, human neutrophil peptides (HNP) 1-3 and bacterial permeability-increasing protein (BPI) expression in cord blood of preterm infants were influenced by the cause of preterm delivery, that is increased levels in infants with clinical amniotic infection. AMP levels also weakly correlated with white blood cell and neutrophil count at birth. In the whole cohort, no association between gestational age or birthweight with AMP levels was found. In the subgroup of infants without clinical amniotic infection (n = 77 preterm infants, n = 36 healthy term infants), we noted a weak correlation between gestational age and lactoferrin, calprotectin and HNP1-3 levels. In addition to that, we observed higher levels of lactoferrin and HNP1-3 in large-for-gestational-age infants.
  
  
  CONCLUSIONS
  Our study confirms that several factors influence cord blood AMP levels which underlines the difficulties of using AMP levels as biomarkers of immunological response.
authors.affiliation: Department of Paediatrics, University of Lübeck, Lübeck, Germany.
authors.forename: Kirstin
authors.initials: K
authors.lastname: Faust
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Göpel
authors.forename: Katja
authors.initials: K
authors.lastname: Moser
authors.forename: Gloriette
authors.initials: G
authors.lastname: Temole
authors.forename: Maren
authors.initials: M
authors.lastname: Bartels
authors.forename: Christian
authors.initials: C
authors.lastname: Wieg
authors.forename: Birte
authors.initials: B
authors.lastname: Tröger
authors.forename: Egbert
authors.initials: E
authors.lastname: Herting
authors.forename: Christoph
authors.initials: C
authors.lastname: Härtel
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000097:blood*; D001798:Blood Proteins; D005260:Female; D005312:Fetal Blood / Q000276:immunology*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007781:Lactoferrin / Q000097:blood*; D008297:Male; D011446:Prospective Studies; D047929:Term Birth; D023084:alpha-Defensins / Q000097:blood*
chemical_list: D023181:Antimicrobial Cationic Peptides; D001798:Blood Proteins; D023084:alpha-Defensins; C021623:bactericidal permeability increasing protein; D007781:Lactoferrin
keywords: Amniotic infection; Antimicrobial peptides; Innate immune system; Preterm infants