Glucocerebrosidase deficiency dramatically impairs human bone marrow haematopoiesis in an in vitro model of Gaucher disease.
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.
Berger
Juliette
J
Hématologie Biologique, CHU Estaing, 1 place L. Aubrac, 63003 Clermont-Ferrand Cedex 1, France.
Lecourt
Séverine
S
Vanneaux
Valérie
V
Rapatel
Chantal
C
Boisgard
Stéphane
S
Caillaud
Catherine
C
Boiret-Dupré
Nathalie
N
Chomienne
Christine
C
Marolleau
Jean-Pierre
JP
Larghero
Jérôme
J
Berger
Marc G
MG
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
D004791:Enzyme Inhibitors; D007294:Inositol; D005962:Glucosylceramidase; C011423:conduritol epoxide