title: Extensive proliferative capacity of single isolated CD34 human cord blood cells in suspension culture.
abstract: Nonadherent, low-density T-lymphocyte-depleted (NALT-) CD34 cells from normal human cord blood were assessed in suspension culture for the effects of recombinant cytokines on their proliferation, differentiation, and generation of myeloid progenitor cells. In this cell population, 82% of cells expressed c-kit protein as assessed by in situ hybridization, and their cloning efficiency was 85% when cells were plated at low cell numbers with combinations of growth factors. CD34 cells were sorted as 1, 5, or 10 cell(s) per well and also at 5000 cells per dish to initiate stromal-free suspension cultures in the presence of steel factor (SLF), interleukin (IL)-1 alpha, and IL-3. Forty-eight percent of the wells started with a single CD34 cell were positive for growth after 14 days, and the wells contained greater than 5 x 10(3) cells by 21-28 days. Progenitors were assayed weekly with cultures initiated with 1 or 5000 cells. While the fold expansion of nucleated cells was greater in cultures initiated with one cell per well (> 5000 compared to 791-fold expansion for 5000 cells), the fold expansion of progenitors was greater than 5000 cells were used to initiate cultures. Under optimal conditions, there was, respectively, a 160-, 164-, and 57-fold output of high proliferative potential colony-forming cells, granulocyte-macrophage colony-forming units, and erythroid burst-forming units/granulocyte erythroid macrophage megakaryocyte colony-forming units within 1-3 weeks for cultures initiated with 5000 CD34 cells compared with respective fold increases of 29, 16, and 1, for single-initiated cultures. These results demonstrate the expansion capacity of single CD34 cord blood cells and demonstrate that factors in addition to SLF, IL-1 alpha, and IL-3 are necessary for optimal expansion of progenitors from single isolated CD34 cells.
authors.affiliation: Department of Medicine, (Hematology/Oncology), Indiana University School of Medicine, Indianapolis 46202-5121, USA.
authors.forename: M
authors.initials: M
authors.lastname: Xiao
authors.forename: H E
authors.initials: HE
authors.lastname: Broxmeyer
authors.forename: M
authors.initials: M
authors.lastname: Horie
authors.forename: S
authors.initials: S
authors.lastname: Grigsby
authors.forename: L
authors.initials: L
authors.lastname: Lu
mesh_terms: D015703:Antigens, CD / Q000032:analysis; D018952:Antigens, CD34; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002469:Cell Separation; D002999:Clone Cells / Q000166:cytology*; D046508:Culture Techniques / Q000379:methods; D004357:Drug Synergism; D005312:Fetal Blood / Q000166:cytology*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D016298:Hematopoietic Cell Growth Factors / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D007377:Interleukin-3 / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D019009:Proto-Oncogene Proteins c-kit; D020794:Receptor Protein-Tyrosine Kinases / Q000096:biosynthesis; D016184:Receptors, Colony-Stimulating Factor / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000494:pharmacology; D019089:Stem Cell Factor
chemical_list: D015703:Antigens, CD; D018952:Antigens, CD34; D016298:Hematopoietic Cell Growth Factors; D007375:Interleukin-1; D007377:Interleukin-3; D011518:Proto-Oncogene Proteins; D016184:Receptors, Colony-Stimulating Factor; D011994:Recombinant Proteins; D019089:Stem Cell Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D019009:Proto-Oncogene Proteins c-kit; D020794:Receptor Protein-Tyrosine Kinases