title: PRC2 inhibition counteracts the culture-associated loss of engraftment potential of human cord blood-derived hematopoietic stem and progenitor cells.
abstract: Cord blood hematopoietic stem cells (CB-HSCs) are an outstanding source for transplantation approaches. However, the amount of cells per donor is limited and culture expansion of CB-HSCs is accompanied by a loss of engraftment potential. In order to analyze the molecular mechanisms leading to this impaired potential we profiled global and local epigenotypes during the expansion of human CB hematopoietic stem and progenitor cells (HPSCs). Human CB-derived CD34+ cells were cultured in serum-free medium together with SCF, TPO, FGF, with or without Igfbp2 and Angptl5 (STF/STFIA cocktails). As compared to the STF cocktail, the STFIA cocktail maintains in vivo repopulation capacity of cultured CD34+ cells. Upon expansion, CD34+ cells genome-wide remodel their epigenotype and depending on the cytokine cocktail, cells show different H3K4me3 and H3K27me3 levels. Expanding cells without Igfbp2 and Angptl5 leads to higher global H3K27me3 levels. ChIPseq analyses reveal a cytokine cocktail-dependent redistribution of H3K27me3 profiles. Inhibition of the PRC2 component EZH2 counteracts the culture-associated loss of NOD scid gamma (NSG) engraftment potential. Collectively, our data reveal chromatin dynamics that underlie the culture-associated loss of engraftment potential. We identify PRC2 component EZH2 as being involved in the loss of engraftment potential during the in vitro expansion of HPSCs.
authors.affiliation: Institute of Medical Radiology and Cell Research (MSZ) in the Center for Experimental Molecular Medicine (ZEMM), University of Würzburg, Würzburg, Germany.
authors.forename: Linda
authors.initials: L
authors.lastname: Varagnolo
authors.affiliation: Department of Cell Biology, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Lin
authors.affiliation: School of Cancer Sciences, University of Birmingham, Birmingham, United Kingdom.
authors.forename: Nadine
authors.initials: N
authors.lastname: Obier
authors.affiliation: Department of Epigenomics and Cancer Risk Factors, German Cancer Research Center (DKFZ), Heidelberg, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Plass
authors.affiliation: Department of Gynecology and Obstetrics, Medical University of Würzburg, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Dietl
authors.affiliation: Department of Cell Biology, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Zenke
authors.affiliation: 1] Department of Epigenomics and Cancer Risk Factors, German Cancer Research Center (DKFZ), Heidelberg, Germany [2] Department of Medicine, Div. Hematology, Oncology and Stem Cell Transplantation, University of Freiburg Medical Center, Freiburg, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Claus
authors.affiliation: Institute of Medical Radiology and Cell Research (MSZ) in the Center for Experimental Molecular Medicine (ZEMM), University of Würzburg, Würzburg, Germany.
authors.forename: Albrecht M
authors.initials: AM
authors.lastname: Müller
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000378:metabolism; D002478:Cells, Cultured; D002843:Chromatin / Q000378:metabolism; D005260:Female; D005312:Fetal Blood / Q000166:cytology* / Q000378:metabolism; D006085:Graft Survival / Q000502:physiology*; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D051379:Mice; D016513:Mice, SCID; D063151:Polycomb Repressive Complex 2 / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D014183:Transplantation, Heterologous / Q000379:methods
chemical_list: D018952:Antigens, CD34; D002843:Chromatin; D063151:Polycomb Repressive Complex 2