title: Immunophenotypic and functional characterization of CD33(+)CD34(+) cells in human cord blood of preterm neonates.
abstract: OBJECTIVE
  To characterize CD33(+)CD34(+) cells, a major population in human cord blood (CB) CD34(+) cells of preterm neonates.
  
  
  METHODS
  The proportion of CD33(+) cells was analyzed on CB CD34(+) cells from preterm and full-term neonates. CD33(+)CD34(+) cells were purified by cell sorting and analyzed on their clonogenic activity, proliferative activity in short-time liquid suspension culture, and GATA-2 mRNA expression by RT-PCR and Southern blot.
  
  
  RESULTS
  The absolute numbers and proportion of CD34(+) cells in mononuclear cells inversely correlated with gestational age. CD33 was expressed on a majority of CB CD34(+) cells of preterm neonates but on only a minor population of them in full-term neonates. In addition, CD33 was dominantly expressed on CD38(-)CD34(+) cells or CD117(low)CD34(+) cells in CB of preterm neonates. CD33(+)CD34(+) cells of preterm cord blood had high proliferative and reproducible potentials compared with CD33(-)CD34(+) cells. CD33(+)CD34(+) cells as well as CD33(-)CD34(+) cells from preterm CB highly expressed GATA-2, in contrast to those from BM.
  
  
  CONCLUSIONS
  These results suggest that CD33(+)CD34(+) cells, which are a major population in CB CD34(+) cells of preterm neonates, do not simply represent relatively mature myeloid lineage hematopoietic progenitor cells as those in adult BM CD34(+) cells, and may contain hematopoietic stem cells or primitive progenitor cells as in fetal liver.
authors.affiliation: Departments of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: C H
authors.initials: CH
authors.lastname: Jin
authors.forename: H
authors.initials: H
authors.lastname: Takada
authors.forename: A
authors.initials: A
authors.lastname: Nomura
authors.forename: Y
authors.initials: Y
authors.lastname: Takahata
authors.forename: H
authors.initials: H
authors.lastname: Nakayama
authors.forename: M
authors.initials: M
authors.lastname: Kajiwara
authors.forename: H
authors.initials: H
authors.lastname: Nakano
authors.forename: T
authors.initials: T
authors.lastname: Hara
mesh_terms: D015703:Antigens, CD / Q000032:analysis*; D018952:Antigens, CD34 / Q000032:analysis*; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis*; D015139:Blotting, Southern; D001854:Bone Marrow Cells / Q000737:chemistry; D002469:Cell Separation; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000235:genetics; D005312:Fetal Blood / Q000166:cytology*; D005434:Flow Cytometry; D050989:GATA2 Transcription Factor; D015870:Gene Expression; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology*; D006801:Humans; D016130:Immunophenotyping; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D063268:Sialic Acid Binding Ig-like Lectin 3; D014157:Transcription Factors / Q000235:genetics
chemical_list: D015703:Antigens, CD; D018952:Antigens, CD34; D015214:Antigens, Differentiation, Myelomonocytic; C571163:CD33 protein, human; D004268:DNA-Binding Proteins; D050989:GATA2 Transcription Factor; C494711:GATA2 protein, human; D012333:RNA, Messenger; D063268:Sialic Acid Binding Ig-like Lectin 3; D014157:Transcription Factors