title: Circulating CD34(+) cells are elevated in neonates with respiratory distress syndrome.
abstract: OBJECTIVE
  The objective of the paper was to determine whether circulating stem-progenitor cells were elevated along with its mobilizing cytokines in neonatal respiratory distress syndrome (RDS).
  
  
  METHODS
  Circulating CD34(+) cells were identified by flow cytometry in 41 RDS in comparison with 20 preterm and 14 term controls without diffuse lung diseases. Plasma concentrations of vascular endothelial growth factor, stromal cell-derived factor-1 (SDF-1) and granulocyte-macrophage colony-stimulating factor were determined by immunochemical assays.
  
  
  RESULTS
  The number of CD34(+) cells was significantly higher in RDS [25(6-174) cells/microl] than in the preterm controls [15(1-100) cells/microl, P < 0.05]. RDS survivors had higher level of CD34(+) cells than non-survivors (P < 0.05), and low CD34(+) cell level in RDS was correlated with prolonged duration of ventilation (r = -0.396, P < 0.05). Likewise, the CD34(+) cell level was inversely associated with Score for Neonatal Acute Physiology Perinatal Extension II (r = -0.473, P < 0.01) in RDS. Plasma SDF-1 concentration was significantly higher in RDS than in the preterm controls (P < 0.01), and was correlated with the level of CD34(+) cells (r = 0.305, P < 0.01).
  
  
  CONCLUSIONS
  The level of circulating CD34(+) cells was elevated in RDS along with an increase of plasma SDF-1, suggesting CD34(+) cells might be involved in reparation of neonatal lung injury.
authors.affiliation: Department of Pediatrics, Children's Hospital, The Institute of Biomedical Sciences, Fudan University, 399 Wan Yuan Road, Shanghai 201102, People's Republic of China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Qi
authors.forename: Liling
authors.initials: L
authors.lastname: Qian
authors.forename: Bo
authors.initials: B
authors.lastname: Sun
authors.forename: Chao
authors.initials: C
authors.lastname: Chen
authors.forename: Yun
authors.initials: Y
authors.lastname: Cao
mesh_terms: D018952:Antigens, CD34 / Q000097:blood*; D002469:Cell Separation; D054377:Chemokine CXCL12 / Q000097:blood; D005434:Flow Cytometry; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000097:blood; D006801:Humans; D007231:Infant, Newborn; D012127:Respiratory Distress Syndrome, Newborn / Q000097:blood / Q000276:immunology; D013234:Stem Cells / Q000166:cytology / Q000276:immunology; D042461:Vascular Endothelial Growth Factor A / Q000097:blood
chemical_list: D018952:Antigens, CD34; D054377:Chemokine CXCL12; D042461:Vascular Endothelial Growth Factor A; D016178:Granulocyte-Macrophage Colony-Stimulating Factor