title: Phenotypic and functional comparison of mobilized peripheral blood versus umbilical cord blood megakaryocyte populations.
abstract: OBJECTIVE
  Hematopoietic stem cell transplantation of mobilized peripheral blood progenitor cell (PBPC) products results in rapid platelet engraftment, whereas the use of cord blood (CB) shows significant delays. The difference in the quality and number of megakaryocyte (MK) progenitors that may be responsible for the delay in platelet engraftment has not been fully defined. The objective of this study was to quantify the cells of the MK lineage in PBPC and CB products to determine whether potential differences exist.
  
  
  METHODS
  We examined PBPC or CB for differences in surface markers and subpopulations as well as polyploidization status within the MK lineage. Colony-forming assays were used to determine whether differences exist in the clonogenic MK progenitor cell. Finally, we transplanted PBPC and CB mononuclear cells into NOD/SCID/IL2Rγ-/- (NSG) mice to study platelet engraftment rates.
  
  
  RESULTS
  Equivalent MK populations and polyploidization was observed in PBPCs and CB. MK progenitors were present only in CD34+ cells and had little difference in colony growth between PBPC and CB. Additionally, MK subpopulations were similar in either product with a slightly more progenitor-enriched phenotype in CB. Finally, when PBPC or CB was transplanted at similar doses, equivalent platelet engraftment rates were observed.
  
  
  CONCLUSIONS
  PBPC and CB contain similar frequencies of MK populations, and, when transplanted in comparable doses, CB is as effective as PBPCs in producing platelet engraftment in vivo. Understanding the differences in MK populations between PBPC and CB could help generate protocols to improve platelet engraftment after CB transplantation.
authors.affiliation: Division of Stem Cell Transplantation and Cellular Therapy, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: Kellner
authors.affiliation: Division of Stem Cell Transplantation and Cellular Therapy, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Sufang
authors.initials: S
authors.lastname: Li
authors.affiliation: Division of Stem Cell Transplantation and Cellular Therapy, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Patrick A
authors.initials: PA
authors.lastname: Zweidler-McKay
authors.affiliation: Division of Stem Cell Transplantation and Cellular Therapy, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Shpall
authors.affiliation: Division of Stem Cell Transplantation and Cellular Therapy, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. Electronic address: imcniece@mdanderson.org.
authors.forename: Ian
authors.initials: I
authors.lastname: McNiece
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000276:immunology; D001792:Blood Platelets / Q000166:cytology*; D002478:Cells, Cultured; D005312:Fetal Blood / Q000166:cytology; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000637:transplantation*; D055016:Megakaryocyte Progenitor Cells / Q000166:cytology*; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D017713:Platelet Transfusion
chemical_list: D018952:Antigens, CD34
keywords: cord blood; megakaryocyte; peripheral blood progenitor cell; platelet engraftment