title: Endothelial precursor cells in the peripheral blood of pregnant women.
abstract: OBJECTIVE
  To determine whether primitive endothelial precursor cells are present in the peripheral blood of pregnant compared with nonpregnant subjects and whether these precursor cells are of fetal or maternal origin.
  
  
  METHODS
  Peripheral blood mononuclear cells from 13 pregnant women in the second trimester and from ten nonpregnant women and men were cultured for 8-10 weeks under conditions that promoted endothelial cell development. Early outgrowth (1 week culture) and late outgrowth (4-6 weeks) colonies were observed, their endothelial nature was investigated, and fluorescence in situ hybridization was performed to determine the origin of the colonies from pregnant women's specimens.
  
  
  RESULTS
  Peripheral blood mononuclear cell cultures from all pregnant women and all nonpregnant controls yielded early-outgrowth endothelial cells. Late-outgrowth endothelial cells were observed in 61.5% (eight of 13) of pregnant subjects, but in none of the ten nonpregnant controls (chi(2) test; P <.01). The adherent cells stained positively for von Willebrand factor and incorporated Dil-Ac-LDL, confirming their endothelial origin. Fluorescence in situ hybridization analysis showed only X chromosome-specific signals and no Y chromosome-specific signals in the cells from the late-outgrowth endothelial cells in all pregnant women carrying either a male (n = 5) or a female (n = 8) fetus.
  
  
  CONCLUSIONS
  Primitive endothelial precursor cells are present in most pregnant women during the second trimester. These cells appear to be of maternal origin.
authors.affiliation: Department of Obstetrics and Gynecology, University of Illinois, Chicago, Illinois 60612, USA.
authors.forename: Hélène A Elicha
authors.initials: HA
authors.lastname: Gussin
authors.forename: Farideh Z
authors.initials: FZ
authors.lastname: Bischoff
authors.forename: Ronald
authors.initials: R
authors.lastname: Hoffman
authors.forename: Sherman
authors.initials: S
authors.lastname: Elias
mesh_terms: D000328:Adult; D001773:Blood Cells / Q000166:cytology*; D002232:Carbocyanines; D002455:Cell Division; D002469:Cell Separation; D002478:Cells, Cultured; D041321:Chromosomes, Human, X; D041322:Chromosomes, Human, Y; D004730:Endothelium, Vascular / Q000166:cytology*; D005260:Female; D005333:Fetus / Q000166:cytology; D005456:Fluorescent Dyes; D005865:Gestational Age; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007963:Leukocytes, Mononuclear / Q000166:cytology; D008297:Male; D011247:Pregnancy; D013194:Staining and Labeling; D013234:Stem Cells / Q000166:cytology*; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D002232:Carbocyanines; D005456:Fluorescent Dyes; D014841:von Willebrand Factor; C024286:3,3'-dioctadecylindocarbocyanine