title: Preterm labor and chorioamnionitis are associated with neonatal T cell activation.
abstract: BACKGROUND
  Preterm parturition is characterized by innate immune activation and increased proinflammatory cytokine levels. This well established association leads us to hypothesize that preterm delivery is also associated with neonatal T lymphocyte activation and maturation.
  
  
  RESULTS
  Cord blood samples were obtained following term, preterm, and deliveries complicated by clinical chorioamnionitis. Activation marker expression was quantitated by flow cytometric analysis. Infants born following preterm delivery demonstrated enhanced CD4(+) T lymphocyte activation, as determined by CD25 (Term 9.72% vs. Preterm 17.67%, p = 0.0001), HLA-DR (Term 0.91% vs. Preterm 1.92%, p = 0.0012), and CD69 expression (Term 0.38% vs. Preterm 1.20%, p = 0.0003). Neonates delivered following clinical chorioamnionitis also demonstrated increased T cell activation. Preterm neonates had an increased frequency of CD45RO(+) T cells.
  
  
  CONCLUSIONS
  Preterm parturition is associated with neonatal CD4(+) T cell activation, and an increased frequency of CD45RO(+) T cells. These findings support the concept that activation of the fetal adaptive immune system in utero is closely associated with preterm labor.
authors.affiliation: Department of Pediatrics, Division of Neonatology, University of South Florida, College of Medicine, Tampa, Florida, United States of America.
authors.forename: Angel A
authors.initials: AA
authors.lastname: Luciano
authors.forename: Haiyan
authors.initials: H
authors.lastname: Yu
authors.forename: Leila W
authors.initials: LW
authors.lastname: Jackson
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Wolfe
authors.forename: Helene B
authors.initials: HB
authors.lastname: Bernstein
mesh_terms: D056704:Adaptive Immunity / Q000276:immunology; D000328:Adult; D002821:Chorioamnionitis / Q000276:immunology* / Q000378:metabolism; D005260:Female; D005333:Fetus / Q000276:immunology; D006801:Humans; D007231:Infant, Newborn; D017493:Leukocyte Common Antigens / Q000378:metabolism; D007752:Obstetric Labor, Premature / Q000276:immunology* / Q000378:metabolism; D011247:Pregnancy; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism
chemical_list: D017493:Leukocyte Common Antigens