1. Long-term Transgene Expression from Plasmid DNA Gene Therapy Vectors Is Negatively Affected by CpG Dinucleotides
- Author
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Hodges, Bradley L., Taylor, Kristin M., Joseph, Macy F., Bourgeois, Sarah A., and Scheule, Ronald K.
- Subjects
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GENE therapy , *GENETIC engineering , *HEMOPHILIA , *BLOOD diseases - Abstract
CpG-reduced, CMV-based plasmid DNA constructs encoding human α-galactosidase A and factor IX were injected into C57Bl/6, BALB/c, and CD1 mice using hydrodynamics-based delivery of plasmid DNA (pDNA), and gene expression was monitored for 6 months. Linearized and supercoiled pDNAs were compared for their abilities to support long-term expression and to generate immune responses to the transgene product. In all mouse strains supercoiled CpG-reduced pDNA encoding α-galactosidase A and factor IX generated higher and more sustained levels of circulating gene product than their supercoiled CpG-replete analogs. Linearizing supercoiled CpG-reduced pDNA did not significantly increase levels of circulating gene product beyond levels supercoiled CpG-reduced pDNA could achieve. Linearizing supercoiled CpG-replete pDNA vectors significantly increased expression compared to their supercoiled CpG-replete analogs, but the increase was short-lived or subtherapeutic. Regardless of vector, liver depot expression did not elicit significant antibody responses to human α-galactosidase A or factor IX. Taken together, these data suggest that a clinically acceptable hydrodynamics-based approach targeting the liver combined with CpG-reduced pDNA vectors may represent a viable option for individuals with hemophilia, a lysosomal storage disease, or other disease in which prolonged depot expression of a therapeutic protein from the liver is desirable. [Copyright &y& Elsevier]
- Published
- 2004
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