COMPOUNDS AND METHODS FOR ENHANCING DELIVERY OF FREE POLYNUCLEOTIDE

摘要

The discovery of simple, nontoxic, and pharmaceutically defined methods for genetic modification of cells and tissues would enable development of a variety of molecular medicines. "Free", "direct", or "naked" polynucleotide administration is a simple, apparently safe, and pharmaceutically defined polynucleotide delivery method. Murine, macaque, and clinical human experiments have demonstrated transfection of various tissues, such as respiratory tissues, after direct application of "free" polynucleotide. However, direct DNA transfection is relatively inefficient in comparison to many transduction systems. The invention herein is directed to transfection enhancing agents which augment the transfection activity of "free" polynucleotide, thereby facilitating the development of simple and safe alternatives to tissue transfection, more particularly respiratory tissue transfection. The experiments described herein indicate that nucleases, both extra-and intra-cellular, present in many biological fluids, such as respiratory fluid, accelerate clearance of biologically active plasmid from the tissue, and that co-administration of a nuclease inhibitor together with free polynucleotide results in marked enhancement of expression of the polynucleotide of interest. These findings support the disclosed invention of an improved polynucleotide delivery system, a "free" plasmid-based transfection technology.