Patents
1. Erythrocyte ghosts containing a desired gene for biocompatible gene systems
​Korea Patent, Registration Date; 27 December 2004
The use of erythrocyte ghosts (EG) as a biocompatible nonviral delivery system for extended circulation and prolonged expression of plasmid DNA in the blood.
1) EG-mediated gene delivery revealed higher and more prolonged mRNA expression levels of plasmid DNA in the blood until 9 days after the single intravenous injection.
2) Plasmid DNA-loaded EG showed gene expression targeted to the blood cells. At 3 days post-dose, substantial expression levels of plasmid DNA delivered in EG were observed only in the blood and not in the other organs.
3) Of the blood cells, the subpopulation containing granulocytes showed higher expression of plasmid DNA than mononuclear cells.
These results indicate the potential of EG as a safe, prolonged and blood-targeted delivery system of therapeutic genes.
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2. N4 modifications of pyrimidine analogs and uses thereof
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2′-Deoxy-N4-[2-(4-nitrophenyl)ethoxycarbonyl]-5-azacytidine (NPEOC-DAC), decitabine with a modification of the N4 position of the azacitidine ring can be used to inhibit DNA methyltransferase. This modification protects the azacitidine ring and can be cleaved by carboxylesterase to release decitabine. NPEOC-DAC was 23-fold less potent at low doses (<10 μM) than decitabine at inhibiting DNA methylation, and was also associated with a 3-day delay in its effect. However, at doses ⩾10 μM NPEOC-DAC was more effective at inhibiting DNA methylation. Theses differences between decitabine and NPEOC-DAC are dependent on the cleavage of the carboxylester bond, and could be potentially exploited pharmacologically.
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