title: Effect of chorioamnionitis on regulatory T cells in moderate/late preterm neonates.
abstract: Regulatory T-cells (Treg) have a protective role for the control of immune activation and tissue damage. The effects of chorioamnionitis (chorio) on Treg in moderate/late preterm newborns are not known. We hypothesized that infants exposed to chorio would have decreased Treg frequency and/or function. We isolated mononuclear cells from adult peripheral blood and cord blood from term and moderate/late preterm infants who were classified for severity of chorio exposure. Mononuclear cells were analyzed by flow cytometry for Treg frequency and phenotype. Treg suppression of activation of conventional T-cells (Tcon) was also quantified. Treg frequencies were similar in all groups of neonates, but lower than that found in adults. Newborn Treg had a naïve phenotype, with decreased levels of CD45RO, HLA-DR, CD39 and TIGIT compared to adult Treg and chorio did not affect the phenotype. Treg from preterm newborns exposed to severe chorio had higher expression of Ki67 compared to the other groups. Treg from preterm newborns were less suppressive than Treg from adults or term, and the level of suppression was reduced with severe chorio. Relative to term, Treg frequency and phenotype were not affected by prematurity and chorio but their functionality was decreased. Lower Treg activity may contribute to inflammation in newborns that is often associated with chorioamnionitis.
authors.affiliation: Division of Immunobiology, Cincinnati Children's Hospital Research Foundation, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
authors.forename: Cesar M
authors.initials: CM
authors.lastname: Rueda
authors.affiliation: Division of Immunobiology, Cincinnati Children's Hospital Research Foundation, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
authors.forename: Casey B
authors.initials: CB
authors.lastname: Wells
authors.affiliation: Division of Neonatology/Pulmonary Biology, The Perinatal Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, OH, USA.
authors.forename: Tate
authors.initials: T
authors.lastname: Gisslen
authors.affiliation: Division of Neonatology/Pulmonary Biology, The Perinatal Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, OH, USA.
authors.forename: Alan H
authors.initials: AH
authors.lastname: Jobe
authors.affiliation: Division of Neonatology/Pulmonary Biology, The Perinatal Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, OH, USA.
authors.forename: Suhas G
authors.initials: SG
authors.lastname: Kallapur
authors.affiliation: Division of Immunobiology, Cincinnati Children's Hospital Research Foundation, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA. Electronic address: Claire.Chougnet@cchmc.org.
authors.forename: Claire A
authors.initials: CA
authors.lastname: Chougnet
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000235:genetics / Q000276:immunology; D001081:Apyrase / Q000235:genetics / Q000276:immunology; D002469:Cell Separation; D002821:Chorioamnionitis / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D005260:Female; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology; D015870:Gene Expression; D006684:HLA-DR Antigens / Q000235:genetics / Q000276:immunology; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000276:immunology*; D019394:Ki-67 Antigen / Q000235:genetics / Q000276:immunology; D017493:Leukocyte Common Antigens / Q000235:genetics / Q000276:immunology; D008213:Lymphocyte Activation; D010641:Phenotype; D011247:Pregnancy; D061251:Primary Cell Culture; D011971:Receptors, Immunologic / Q000235:genetics / Q000276:immunology; D012720:Severity of Illness Index; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000473:pathology
chemical_list: D015703:Antigens, CD; D006684:HLA-DR Antigens; D019394:Ki-67 Antigen; D011971:Receptors, Immunologic; C534712:TIGIT protein, human; D017493:Leukocyte Common Antigens; D001081:Apyrase; C067869:CD39 antigen
keywords: Fetal inflammation; Full term newborn; Prematurity; Regulatory T cell; Suppression