title: Platelet-derived growth factor enhances expansion of umbilical cord blood CD34+ cells in contact with hematopoietic stroma.
abstract: Stem cell expansion remains an elusive but highly desirable goal. Here we show that platelet-derived growth factor (PDGF), along with cultured endothelial or stromal cells, significantly enhances expansion of human CD34+ cells in vitro. In media supplemented with thrombopoietin, stem cell factor, flt-3 ligand, and granulocyte-colony stimulating factor, CD34+ cells, as well as CFU-GM, BFU-CFU-E, CFU-GEMM, and CFU-MK, increased by 34.3-, 138-, 59.7-, 38.4-, and 86.0-fold, respectively. Co-culturing of CD34+ cells with cultured stromal cells or human umbilical cord vein endothelial cells (HUVECs) greatly enhanced expansion efficiency. The presence of PDGF (50 ng/ml) further augmented expansion, such that increases of 77.0-, 262-, 90.0-, 93.0-, and 200-fold, respectively, were achieved. Six weeks after infusion of expanded cells into NOD/SCID mice, human CD45+ cells were detected in recipients' bone marrow, spleen, and peripheral blood. Our results provide a rationale for development of a stem cell expansion protocol for clinical applications.
authors.affiliation: Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong.
authors.forename: Rui Jun
authors.initials: RJ
authors.lastname: Su
authors.forename: Karen
authors.initials: K
authors.lastname: Li
authors.forename: Xiao Bing
authors.initials: XB
authors.lastname: Zhang
authors.forename: Patrick Man
authors.initials: PM
authors.lastname: Pan Yuen
authors.forename: Chi Kong
authors.initials: CK
authors.lastname: Li
authors.forename: Anthony Edward
authors.initials: AE
authors.lastname: James
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.forename: Tai Fai
authors.initials: TF
authors.lastname: Fok
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000096:biosynthesis*; D001854:Bone Marrow Cells / Q000166:cytology; D018929:Cell Culture Techniques / Q000379:methods; D002462:Cell Membrane / Q000378:metabolism; D049109:Cell Proliferation; D002478:Cells, Cultured; D018920:Coculture Techniques; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000166:cytology; D005312:Fetal Blood / Q000166:cytology*; D005434:Flow Cytometry; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D006413:Hematopoietic System; D006801:Humans; D039661:Integrin beta3 / Q000096:biosynthesis; D017493:Leukocyte Common Antigens / Q000096:biosynthesis; D018950:Lipopolysaccharide Receptors / Q000096:biosynthesis; D008533:Megakaryocytes / Q000166:cytology; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D010982:Platelet-Derived Growth Factor / Q000378:metabolism / Q000502:physiology*; D019718:Receptors, CXCR4 / Q000378:metabolism; D013154:Spleen / Q000166:cytology; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D017154:Stromal Cells / Q000166:cytology; D013997:Time Factors; D014471:Umbilical Veins / Q000166:cytology / Q000378:metabolism*
chemical_list: D018952:Antigens, CD34; D016895:Culture Media, Serum-Free; D039661:Integrin beta3; D018950:Lipopolysaccharide Receptors; D010982:Platelet-Derived Growth Factor; D019718:Receptors, CXCR4; D017493:Leukocyte Common Antigens