title: IFN-gamma negatively modulates self-renewal of repopulating human hemopoietic stem cells.
abstract: Whereas multiple growth-promoting cytokines have been demonstrated to be involved in regulation of the hemopoietic stem cell (HSC) pool, the potential role of negative regulators is less clear. However, IFN-gamma, if overexpressed, can mediate bone marrow suppression and has been directly implicated in a number of bone marrow failure syndromes, including graft-vs-host disease. Whether IFN-gamma might directly affect the function of repopulating HSCs has, however, not been investigated. In the present study, we used in vitro conditions promoting self-renewing divisions of human HSCs to investigate the effect of IFN-gamma on HSC maintenance and function. Although purified cord blood CD34(+)CD38(-) cells underwent cell divisions in the presence of IFN-gamma, cycling HSCs exposed to IFN-gamma in vitro were severely compromised in their ability to reconstitute long-term cultures in vitro and multilineage engraft NOD-SCID mice in vivo (>90% reduced activity in both HSC assays). In vitro studies suggested that IFN-gamma accelerated differentiation of targeted human stem and progenitor cells. These results demonstrate that IFN-gamma can negatively affect human HSC self-renewal.
authors.affiliation: Hemopoietic Stem Cell Laboratory, Lund Strategic Research Center for Stem Cell Biology and Cell Therapy, Lund University, Lund, Sweden.
authors.forename: Liping
authors.initials: L
authors.lastname: Yang
authors.forename: Ingunn
authors.initials: I
authors.lastname: Dybedal
authors.forename: David
authors.initials: D
authors.lastname: Bryder
authors.forename: Lars
authors.initials: L
authors.lastname: Nilsson
authors.forename: Ewa
authors.initials: E
authors.lastname: Sitnicka
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Sasaki
authors.forename: Sten Eirik W
authors.initials: SE
authors.lastname: Jacobsen
mesh_terms: D036541:ADP-ribosyl Cyclase / Q000378:metabolism; D051997:ADP-ribosyl Cyclase 1; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D018952:Antigens, CD34 / Q000096:biosynthesis; D002454:Cell Differentiation / Q000276:immunology*; D019070:Cell Lineage / Q000276:immunology; D002478:Cells, Cultured; D002999:Clone Cells; D004306:Dose-Response Relationship, Immunologic; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology; D006131:Growth Inhibitors / Q000502:physiology*; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D016130:Immunophenotyping; D007371:Interferon-gamma / Q000502:physiology*; D008562:Membrane Glycoproteins; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID
chemical_list: D015703:Antigens, CD; D018952:Antigens, CD34; D006131:Growth Inhibitors; D008562:Membrane Glycoproteins; D007371:Interferon-gamma; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; C498155:Cd38 protein, mouse; D051997:ADP-ribosyl Cyclase 1