Experimental hematology
-
Experimental hematology · Nov 1998
Candidate hematopoietic stem cells from fetal tissues, umbilical cord blood vs. adult bone marrow and mobilized peripheral blood.
As part of our ongoing effort to identify a rich source of pluripotent progenitor cells for transplantation and gene therapy, we cultured single-sorted CD34+ subpopulations from different human hematopoietic tissues to assess the relationship between immunophenotype expression and functional characteristics. In combination with index sorting, single cell culture permits precise assessment of the colony efficiency (CE), growth characteristics, and replating potential (RP) of each individual phenotype without interference from other cell types. CD34+ cells from fetal liver (FL), fetal bone marrow (FBM), umbilical cord blood (UCB), adult BM (ABM), and mobilized peripheral blood (MPB) were sorted and cultured as single cells according to the coexpression of CD38. ⋯ We conclude that the CD34+/CD38-/HLA-DR+ subset contained the highest number of candidate stem cells among the various immunophenotypes, and that FL contained the highest concentration of CD34+ cells (11.4+/-7.5%) and the highest level of CD34+/CD38-/HLA-DR+ subsets (34.7+/-8.2%) among cells from various ontogenic age. Our estimate of candidate stem cells using single cell suspension culture correlated with that obtained by single cell long-term culture-initiating cells. CD34+/CD38-/HLA-DR+ cells from FL appear to represent the best targets for ex vivo stem cell expansion and genetic manipulation.