Preselective gene therapy for Fabry disease.

Abstract

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.

• Authors: G Qin, T Takenaka, K Telsch, L Kelley, T Howard, T Levade, R Deans, B H Howard, H L Malech, R O Brady, J A Medin
• Journal: Proceedings of the National Academy of Sciences of the United States of America (Proc Natl Acad Sci U S A) Vol. 98 Issue 6 Pg. 3428-33 (Mar 13 2001) ISSN: 0027-8424 [Print] United States
• PMID: 11248095 (Publication Type: Journal Article)

Chemical References

• Receptors, Interleukin-2
• alpha-Galactosidase

Topics

• 3T3 Cells
• Animals
• Bone Marrow Transplantation
• Disease Models, Animal
• Fabry Disease (metabolism, pathology, therapy)
• Gene Expression
• Genetic Therapy (methods)
• Genetic Vectors
• HeLa Cells
• Humans
• Mice
• Mice, Inbred C57BL
• Receptors, Interleukin-2 (genetics, metabolism)
• Retroviridae (genetics)
• alpha-Galactosidase (genetics, metabolism)