title: Decrease in nucleoside diphosphate kinase (NDPK/nm23) expression during hematopoietic maturation.
abstract: The nucleoside diphosphate kinase (NDPK/nm23) isoforms H1 and H2 were localized in hematopoietic tissues. Flow cytometric analysis and enzymatic assays were used to quantify the intracellular and extracellular concentrations of NDPK. Bone marrow CD34(+) progenitors contained the highest intracellular levels of both nm23-H1 and nm23-H2. Lower levels were measured in more mature bone marrow cells, whereas peripheral blood leukocytes had the lowest expression of nm23. These data suggest a function of NDPK in early hematopoiesis and a down-regulation of NDPK upon differentiation. In addition, an up-regulation of nm23 expression was observed in lymphocytes after induction of proliferation with phytohemagglutinin. Multiparameter flow cytometry demonstrated that this up-regulation occurred during the G0/G1-transition. Flow cytometric analysis also revealed a weak surface expression of nm23 on a number of hematopoietic cell lines, which was not detected on normal hematopoietic cells. Our data also demonstrated the presence of NDPK in human plasma, probably due to a limited in vivo lysis of red blood cells.
authors.affiliation: Laboratory of Experimental Hematology, Department of Medicine, University of Antwerp, Antwerp University Hospital (UIA/UZA), Wilrijkstraat 10, B-2650 Edegem, Belgium.
authors.forename: R
authors.initials: R
authors.lastname: Willems
authors.forename: D R
authors.initials: DR
authors.lastname: Van Bockstaele
authors.forename: F
authors.initials: F
authors.lastname: Lardon
authors.forename: M
authors.initials: M
authors.lastname: Lenjou
authors.forename: G
authors.initials: G
authors.lastname: Nijs
authors.forename: H W
authors.initials: HW
authors.lastname: Snoeck
authors.forename: Z N
authors.initials: ZN
authors.lastname: Berneman
authors.forename: H
authors.initials: H
authors.lastname: Slegers
mesh_terms: D002454:Cell Differentiation; D002462:Cell Membrane / Q000201:enzymology; D005434:Flow Cytometry; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000201:enzymology*; D006801:Humans; D020559:Monomeric GTP-Binding Proteins; D054778:NM23 Nucleoside Diphosphate Kinases; D009701:Nucleoside-Diphosphate Kinase / Q000097:blood*; D014157:Transcription Factors / Q000097:blood*
chemical_list: D054778:NM23 Nucleoside Diphosphate Kinases; D014157:Transcription Factors; C517938:NME1 protein, human; D009701:Nucleoside-Diphosphate Kinase; D020559:Monomeric GTP-Binding Proteins