title: Genetic influences determining progenitor cell mobilization and leukocytosis induced by granulocyte colony-stimulating factor.
abstract: The mechanisms involved in the mobilization of progenitor cells into the blood by granulocyte colony-stimulating factor (G-CSF) and other cytokines are poorly understood. To identify important influences on this complex process, in vivo murine models were used. Granulocyte-macrophage colony-stimulating factor (GM-CSF) transgenic, Max41 transgenic, W/Wv, Mpl-null, GM-CSF receptor (beta chain)-null mice, wild-type littermate controls, and six inbred strains of mice were injected with 200 microg/kg/d G-CSF for 5 days. Three parameters of response were monitored: white blood cell count (WCC), peripheral blood progenitor cell (PBPC) numbers, and spleen weight. In all genotypes studied, G-CSF induced increases in these three parameters. However, PBPC mobilization in W/Wv and Mpl-null mice was only 30% and 9%, respectively, of that observed in wild-type mice. In contrast, perturbations of GM-CSF signalling had no demonstrable effect on in vivo responses to G-CSF. Broad variability was evident between inbred strains for each parameter of the response to G-CSF. A 10-fold range in response was observed for circulating progenitor cell numbers, similar to that observed for normal human subjects receiving G-CSF. The interstrain differences were in the distribution of mature and progenitor cells between peripheral blood, bone marrow, and spleen rather than in the total numbers of these cells in the body. Results of an F2 intercross of low-responding C57BL/6 and intermediate-responding SJL mice indicated that regulation of progenitor cell mobilization is a complex genetic trait, that there is a correlation between this trait and WCC response (r2 = .5), and that this approach may serve as a useful model for the identification of genes involved in the mobilization process.
authors.affiliation: The Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, Victoria, Australia.
authors.forename: A W
authors.initials: AW
authors.lastname: Roberts
authors.forename: S
authors.initials: S
authors.lastname: Foote
authors.forename: W S
authors.initials: WS
authors.lastname: Alexander
authors.forename: C
authors.initials: C
authors.lastname: Scott
authors.forename: L
authors.initials: L
authors.lastname: Robb
authors.forename: D
authors.initials: D
authors.lastname: Metcalf
mesh_terms: D000818:Animals; D001773:Blood Cells / Q000166:cytology; D001853:Bone Marrow / Q000187:drug effects*; D001854:Bone Marrow Cells; D003433:Crosses, Genetic; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology* / Q000633:toxicity; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006410:Hematopoiesis / Q000187:drug effects / Q000235:genetics*; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D015848:Interleukin-5 / Q000494:pharmacology; D007958:Leukocyte Count / Q000187:drug effects; D007964:Leukocytosis / Q000139:chemically induced* / Q000235:genetics; D051379:Mice; D008815:Mice, Inbred Strains / Q000235:genetics*; D018345:Mice, Knockout; D008817:Mice, Mutant Strains; D008822:Mice, Transgenic; D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D019009:Proto-Oncogene Proteins c-kit / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D018121:Receptors, Cytokine; D053628:Receptors, Thrombopoietin; D019089:Stem Cell Factor / Q000494:pharmacology; D013926:Thrombopoietin / Q000494:pharmacology
chemical_list: D015848:Interleukin-5; D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins; D018121:Receptors, Cytokine; D053628:Receptors, Thrombopoietin; D019089:Stem Cell Factor; D016179:Granulocyte Colony-Stimulating Factor; C082218:MPL protein, human; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D013926:Thrombopoietin; D019009:Proto-Oncogene Proteins c-kit