title: Co-culture of human CD34+ cells with mesenchymal stem cells increases the survival of CD34+ cells against the 5-aza-deoxycytidine- or trichostatin A-induced cell death.
abstract: It has been suggested that epigenetic regulation plays an important role in maintaining the stemness and lineage differentiation of hematopoietic stem cells (HSCs), 5-aza-deoxycytidine (aza-D) and Trichostatin A (TSA) being candidate additives for HSC ex vivo expansion. Although they have potent activity to maintain the stemness, they can also cause serious cell death. This study examined the effects of mesenchymal stem cells (MSCs) on the maintenance of CD34+ cells driven by aza-D and TSA in culture with the combined cytokines of thrombopoietin, flt-3 ligand, stem cell factor, interleukin-3, and interleukin-6. In cultures without MSCs, although aza-D and TSA retained the CD34 frequency 4 to 8 times more than in the cytokines alone, a large portion of cells underwent apoptotic cell death. Consequently, CD34+ cell expansion could not be achieved in any condition without MSCs. In cultures with MSCs, the total cell number was higher in aza-D or TSA than in any conditions in the cultures without MSCs. The CD34 frequency was also similar to the level in the cultures in aza-D or TSA without the MSCs. These results suggest that a co-culture of CD34+ cells with the MSCs might not simply deliver the proliferation signals but also stemness and survival signals, and overlap the action of epigenetic regulators.
authors.affiliation: Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sang Hyeok
authors.initials: SH
authors.lastname: Koh
authors.forename: Hyoung Soo
authors.initials: HS
authors.lastname: Choi
authors.forename: Eun Sil
authors.initials: ES
authors.lastname: Park
authors.forename: Hyoung Jin
authors.initials: HJ
authors.lastname: Kang
authors.forename: Hyo Seop
authors.initials: HS
authors.lastname: Ahn
authors.forename: Hee Young
authors.initials: HY
authors.lastname: Shin
mesh_terms: D018952:Antigens, CD34 / Q000378:metabolism*; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D001374:Azacitidine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D048429:Cell Size / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D018920:Coculture Techniques / Q000379:methods; D000077209:Decitabine; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology*; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D023822:Tissue Engineering / Q000379:methods
chemical_list: D018952:Antigens, CD34; D006877:Hydroxamic Acids; C012589:trichostatin A; D000077209:Decitabine; D001374:Azacitidine