Preselective gene therapy for Fabry disease.
Fabry disease is a lipid storage disorder resulting from mutations in the gene encoding the enzyme alpha-galactosidase A (alpha-gal A; EC ). We previously have demonstrated long-term alpha-gal A enzyme correction and lipid reduction mediated by therapeutic ex vivo transduction and transplantation of hematopoietic cells in a mouse model of Fabry disease. We now report marked improvement in the efficiency of this gene-therapy approach. For this study we used a novel bicistronic retroviral vector that engineers expression of both the therapeutic alpha-gal A gene and the human IL-2Ralpha chain (huCD25) gene as a selectable marker. Coexpression of huCD25 allowed selective immunoenrichment (preselection) of a variety of transduced human and murine cells, resulting in enhanced intracellular and secreted alpha-gal A enzyme activities. Of particular significance for clinical applicability, mobilized CD34(+) peripheral blood hematopoietic stem/progenitor cells from Fabry patients have low-background huCD25 expression and could be enriched effectively after ex vivo transduction, resulting in increased alpha-gal A activity. We evaluated effects of preselection in the mouse model of Fabry disease. Preselection of transduced Fabry mouse bone marrow cells elevated the level of multilineage gene-corrected hematopoietic cells in the circulation of transplanted animals and improved in vivo enzymatic activity levels in plasma and organs for more than 6 months after both primary and secondary transplantation. These studies demonstrate the potential of using a huCD25-based preselection strategy to enhance the clinical utility of ex vivo hematopoietic stem/progenitor cell gene therapy of Fabry disease and other disorders.
Qin
G
G
Department of Medicine, University of Illinois, Chicago, IL 60607, USA.
Takenaka
T
T
Telsch
K
K
Kelley
L
L
Howard
T
T
Levade
T
T
Deans
R
R
Howard
B H
BH
Malech
H L
HL
Brady
R O
RO
Medin
J A
JA
D016475:3T3 Cells; D000818:Animals; D016026:Bone Marrow Transplantation; D004195:Disease Models, Animal; D000795:Fabry Disease / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D015870:Gene Expression; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D015375:Receptors, Interleukin-2 / Q000235:genetics* / Q000378:metabolism; D012190:Retroviridae / Q000235:genetics; D000519:alpha-Galactosidase / Q000235:genetics* / Q000378:metabolism
D015375:Receptors, Interleukin-2; D000519:alpha-Galactosidase