title: Expression profiling of circulating non-red blood cells in embryonic blood.
abstract: BACKGROUND
  In addition to erythrocytes, embryonic blood contains other differentiated cell lineages and potential progenitor or stem cells homed to changing niches as the embryo develops. Using chicken as a model system, we have isolated an enriched pool of circulating non red blood cells (nRBCs) from E4 and E6 embryos; a transition period when definitive hematopoietic lineages are being specified in the peri-aortic region.
  
  
  RESULTS
  Transcriptome analysis of both nRBC and RBC enriched populations was performed using chicken Affymetrix gene expression arrays. Comparison of transcript profiles of these two populations, with verification by RT-PCR, reveals in nRBCs an expression signature indicative of hematopoietic stem cells (HSCs) and progenitor cells of myeloid and lymphoid lineages, as well as a number of previously undescribed genes possibly involved in progenitor and stem cell maintenance.
  
  
  CONCLUSIONS
  This data indicates that early circulating embryonic blood contains a full array of hematopoietic progenitors and stem cells. Future studies on their heterogeneity and differentiation potentials may provide a useful alternative to ES cells and perinatal blood.
authors.affiliation: Laboratory for Early Embryogenesis, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan. mcintyre@cdb.riken.jp
authors.forename: Brendan A S
authors.initials: BA
authors.lastname: McIntyre
authors.forename: Cantas
authors.initials: C
authors.lastname: Alev
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tarui
authors.forename: Lars M
authors.initials: LM
authors.lastname: Jakt
authors.forename: Guojun
authors.initials: G
authors.lastname: Sheng
mesh_terms: D000818:Animals; D001773:Blood Cells / Q000166:cytology*; D002454:Cell Differentiation; D019070:Cell Lineage; D002469:Cell Separation; D002642:Chick Embryo / Q000196:embryology*; D005434:Flow Cytometry; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D005819:Genetic Markers; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D005819:Genetic Markers