title: Glucocerebrosidase deficiency dramatically impairs human bone marrow haematopoiesis in an in vitro model of Gaucher disease.
abstract: One of the cardinal symptoms of type 1 Gaucher Disease (GD) is cytopenia, usually explained by bone marrow (BM) infiltration by Gaucher cells and hypersplenism. However, some cases of cytopenia in splenectomized or treated patients suggest possible other mechanisms. To evaluate intra-cellular glucocerebrosidase (GlcC) activity in immature progenitors and to prove the conduritol B epoxide (CBE)-induced inhibition of the enzyme, we used an adapted flow cytometric technique before assessing the direct effect of GlcC deficiency in functional assays. Among haematopoietic cells from healthy donors, monocytes showed the highest GlcC activity but immature CD34(+) and mesenchymal cells also had significant GlcC activity. CBE greatly inhibited the enzyme activity of all cell categories. GlcC-deficient CD34(+) cells showed impaired ability to proliferate and differentiate in the expansion assay and had lower frequency of erythroid burst-forming units, granulocyte colony-forming units (CFU) and macrophage CFU progenitors, but the effect of GlcC deficiency on megakaryocyte CFU lineage was not significant. GlcC deficiency strongly impaired primitive haematopoiesis in long-term culture. Furthermore, GlcC deficiency progressively impaired proliferation of mesenchymal progenitors. These data suggest an intrinsic effect of GlcC deficiency on BM immature cells that supplements the pathophysiology of GD and opens new perspectives of therapeutic approach.
authors.affiliation: Hématologie Biologique, CHU Estaing, 1 place L. Aubrac, 63003 Clermont-Ferrand Cedex 1, France.
authors.forename: Juliette
authors.initials: J
authors.lastname: Berger
authors.forename: Séverine
authors.initials: S
authors.lastname: Lecourt
authors.forename: Valérie
authors.initials: V
authors.lastname: Vanneaux
authors.forename: Chantal
authors.initials: C
authors.lastname: Rapatel
authors.forename: Stéphane
authors.initials: S
authors.lastname: Boisgard
authors.forename: Catherine
authors.initials: C
authors.lastname: Caillaud
authors.forename: Nathalie
authors.initials: N
authors.lastname: Boiret-Dupré
authors.forename: Christine
authors.initials: C
authors.lastname: Chomienne
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Marolleau
authors.forename: Jérôme
authors.initials: J
authors.lastname: Larghero
authors.forename: Marc G
authors.initials: MG
authors.lastname: Berger
mesh_terms: D001854:Bone Marrow Cells / Q000201:enzymology; D049109:Cell Proliferation; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005434:Flow Cytometry / Q000379:methods; D005776:Gaucher Disease / Q000201:enzymology* / Q000503:physiopathology; D005962:Glucosylceramidase / Q000037:antagonists & inhibitors / Q000097:blood / Q000172:deficiency*; D006410:Hematopoiesis / Q000187:drug effects / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000473:pathology; D006801:Humans; D007294:Inositol / Q000031:analogs & derivatives / Q000494:pharmacology; D008954:Models, Biological; D046509:Tissue Culture Techniques
chemical_list: D004791:Enzyme Inhibitors; D007294:Inositol; D005962:Glucosylceramidase; C011423:conduritol epoxide