title: Identification of circulating fetal cell markers by microarray analysis.
abstract: OBJECTIVE
  Different fetal cell types have been found in the maternal blood during pregnancy in the past, but fetal cells are scarce, and the proportions of the different cell types are unclear. The objective of the present study was to identify specific fetal cell markers from fetal cells found in the maternal blood circulation at the end of the first trimester.
  
  
  METHODS
  Twenty-three fetal cells were isolated from maternal blood by removing the red blood cells by lysis or combining this with removal of large proportions of maternal white blood cells by magnetic-activated cell sorting. Fetal cells identified by XY fluorescence in situ hybridization and confirmed by reverse-color fluorescence in situ hybridization were shot off microscope slides by laser capture microdissection. The expression pattern of a subset of expressed genes was compared between fetal cells and maternal blood cells using stem cell microarray analysis.
  
  
  RESULTS
  Twenty-eight genes were identified as fetal cell marker candidates.
  
  
  CONCLUSIONS
  Of the 28 fetal marker candidate genes, five coded for proteins, which are located on the outer surface of the cell membrane and not expressed in blood. The protein product of these five genes, MMP14, MCAM, KCNQ4, CLDN6, and F3, may be used as markers for fetal cell enrichment.
authors.affiliation: FCMB ApS, Vejle, Denmark.
authors.forename: Marie
authors.initials: M
authors.lastname: Brinch
authors.forename: Lotte
authors.initials: L
authors.lastname: Hatt
authors.forename: Ripudaman
authors.initials: R
authors.lastname: Singh
authors.forename: Kristine
authors.initials: K
authors.lastname: Møller
authors.forename: Steffen
authors.initials: S
authors.lastname: Sommer
authors.forename: Niels
authors.initials: N
authors.lastname: Uldbjerg
authors.forename: Britta
authors.initials: B
authors.lastname: Christensen
authors.forename: Steen
authors.initials: S
authors.lastname: Kølvraa
mesh_terms: D015415:Biomarkers / Q000097:blood*; D051929:CD146 Antigen / Q000235:genetics; D057167:Claudins / Q000235:genetics; D018076:DNA, Complementary / Q000032:analysis; D005260:Female; D005333:Fetus / Q000166:cytology*; D005796:Genes; D006801:Humans; D051656:KCNQ Potassium Channels / Q000235:genetics; D061346:Laser Capture Microdissection; D008297:Male; D053511:Matrix Metalloproteinase 14 / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D011247:Pregnancy; D012732:Sex Determination Analysis
chemical_list: D015415:Biomarkers; D051929:CD146 Antigen; D057167:Claudins; D018076:DNA, Complementary; D051656:KCNQ Potassium Channels; C117367:KCNQ4 protein, human; C497902:MCAM protein, human; C507086:MMP14 protein, human; D053511:Matrix Metalloproteinase 14; C122101:claudin 6