title: Proliferation kinetics of subpopulations of human marrow cells determined by quantifying in vivo incorporation of [2H2]-glucose into DNA of S-phase cells.
abstract: This report investigated in vivo turnover kinetics of marrow hematopoietic progenitors and precursors using a recently developed stable isotope-mass spectrometric technique (SIMST). Human subjects were administered a 2-day infusion of 6,6-[2H2]-glucose, a nontoxic stable isotope-labeled form of glucose, which becomes incorporated into DNA of all S-phase cells. The percent [2H2]-glucose incorporated into DNA in the form of [2H2]-deoxyadenosine (%[2H2]-dA enrichment) was determined by gas chromatography-mass spectrometry. The rate constant of replacement of unlabeled by labeled DNA strands (labeling kinetics) was used to calculate population turnover kinetics of CD34+ cells, CD133+ cells, and CD133-CD34+ cells. The observed mean replacement half-life (t1/2) was 2.6 days for CD34+ cells, 2.5 days for CD133-CD34+ cells, and 6.2 days for CD133+ cells. Results from the estimated rate constant of replacement of labeled by unlabeled DNA (delabeling kinetics) also demonstrated slower turnover rates for CD133+ cells than for CD133-CD34+ cells. Although there was a relatively rapid initial decrease in the %[2H2]-dA enrichment, low levels of labeled DNA persisted in CD34+ cells for at least 4 weeks. The results indicate the presence of subpopulations of CD34+ cells with relatively rapid turnover rates and subpopulations with a slower t1/2 of 28 days. Results also demonstrate that in vivo [2H2]-glucose-SIMST is sensitive enough to detect differences in turnover kinetics between erythroid and megakaryocyte lineage cells. These studies are the first to demonstrate the use of in vivo [2H2]-glucose-SIMST to measure in vivo turnover kinetics of subpopulations of CD34+ cells and precursors in healthy human subjects.
authors.affiliation: Experimental Transplantation and Immunology Branch, National Cancer Institute/NIH, Bldg 10, Room 12S237, MSC 1907, 9000 Rockville Pike, Bethesda, MD 20892, USA.
authors.forename: Gretchen N
authors.initials: GN
authors.lastname: Schwartz
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Vance
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Levine
authors.forename: Motoharu
authors.initials: M
authors.lastname: Fukazawa
authors.forename: William G
authors.initials: WG
authors.lastname: Telford
authors.forename: Denise
authors.initials: D
authors.lastname: Cesar
authors.forename: Marc
authors.initials: M
authors.lastname: Hellerstein
authors.forename: Ronald E
authors.initials: RE
authors.lastname: Gress
mesh_terms: D000071916:AC133 Antigen; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD; D018952:Antigens, CD34 / Q000032:analysis; D001854:Bone Marrow Cells / Q000737:chemistry / Q000166:cytology* / Q000378:metabolism*; D002455:Cell Division / Q000502:physiology; D019070:Cell Lineage / Q000502:physiology; D004247:DNA / Q000378:metabolism; D003903:Deuterium; D004912:Erythrocytes / Q000166:cytology; D005260:Female; D005947:Glucose / Q000493:pharmacokinetics; D006023:Glycoproteins / Q000032:analysis; D006410:Hematopoiesis / Q000502:physiology*; D006801:Humans; D007700:Kinetics; D008297:Male; D008533:Megakaryocytes / Q000166:cytology; D010455:Peptides / Q000032:analysis; D016196:S Phase / Q000502:physiology*
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D018952:Antigens, CD34; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; D004247:DNA; D003903:Deuterium; D005947:Glucose