title: Evaluation of umbilical cord blood CD34 (+) hematopoietic stem cell expansion in co-culture with bone marrow mesenchymal stem cells in the presence of TEPA.
abstract: BACKGROUND
  During the last three decades hematopoietic stem cells (HSC) have become a standard protocol for the treatment of many hematologic malignancies and non-malignant disorders. Umbilical cord blood (UCB), as a source of HSCs, has many advantages compared with other  sources. One major drawback in using this source in treatment of adult patients is the low HSC dose available. Ex vivo expansion of HSCs is a solution to overcome this limitation. In this study we used TEPA, as a Cu chelator, and human bone marrow (BM) mesenchymal stem cells (MSCs)  to investigate expansion rate of UCB-HSCs.
  
  
  METHODS
  CB-HSCs were isolated using miniMACS magnetic separation system. We cultured the enriched CD34(+)cells in various conditions: culture condition A, supplemented only with recombinant cytokines; culture  condition B, supplemented with BM-MSCs as a cell feeder layer and recombinant cytokines; culture condition C, supplemented with recombinant cytokines and TEPA; culture condition D, supplemented with recombinant cytokines, BM-MSCs as a cell feeder layer and TEPA. In order to evaluate the HSC  expansion, we performed cell count, analysis of CD34(+) expression by flow cytometry, and colony-forming cell assay on Day 10 after culture.
  
  
  RESULTS
  The most fold increase in CD34(+) cell, total cell, and total colony numbers was observed in culture condition  D (110.11 ± 15.3, 118.5 ± 21, and 172.9 ± 44.7, respectively) compared to other conditions.
  
  
  CONCLUSIONS
  The results showed that co-culture of HSCs with BM-MSCs in the presence of copper chelating agent (TEPA) could dramatically  increase expansion rate of UCB-HSCs. Therefore, this strategy could be useful for HSC expansion.
authors: Department of Hematology, School of Allied Medicine and Molecular and Cellular Research Center, Tehran University of Medical Sciences, 14155-6183 Tehran, Iran. farhadz20@yahoo.co.uk
authors: Farhad
authors: F
authors: Zaker
authors: Nahid
authors: N
authors: Nasiri
authors: Arezoo
authors: A
authors: Oodi
authors: Naser
authors: N
authors: Amirizadeh
mesh_terms: D001854:Bone Marrow Cells / Q000166:cytology* / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D005312:Fetal Blood / Q000166:cytology* / Q000187:drug effects; D005434:Flow Cytometry; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects*; D013721:Triethylenephosphoramide / Q000494:pharmacology*
chemical_list: D013721:Triethylenephosphoramide