Compositions and methods for delivering nucleic acid to a cell

Abstract

Provided are novel compositions useful for delivering nucleic acids to cells. Also provided are methods for making and using such compositions.

Description

RELATED APPLICATIONS[0001]This application is a continuation of PCT International Application No. PCT / US2012 / 025324, filed Feb. 15, 2012, which claims the benefit of U.S. Provisional Patent Application No. 61 / 443,246, filed Feb. 15, 2011. The contents of each of the foregoing applications are incorporated herein by reference in their entirety.BACKGROUND OF THE INVENTION[0002]Introducing nucleic acids into living cells is an important process in modern biological research, industry, and medicine. Efficient delivery of a functional nucleic acid into a living cell is an indispensable component of genetic engineering, recombinant protein production, and medical technologies known as gene therapy.[0003]For example, gene therapy involves the transfer of normal, functional genetic material into specific cells to correct an abnormality due to a deficient or defective gene product. A variety of methods have been developed to facilitate both in vivo, in vitro, or ex vivo gene transfer.[0004]N...

AI Technical Summary

Benefits of technology

The present invention relates to liposome-nucleic acid complexes and methods of making and using them. The invention provides methods for preparing liposomes that have a nucleic acid and a lipid component, which can be a neutral phospholipid and no cationic lipid, or a cationic lipid and a non-cationic lipid. The methods involve combining a lipid component, a polyamine, and a nucleic acid in a mixture containing water, an organic solvent, and a polyamine. The resulting liposomes have a nucleic acid and a lipid component present in a ratio of from 5 nmol lipid per microgram of the nucleic acid to 20, 30, 40, 50, 60, 70, 80, 90, or 100 nmol lipid per microgram of the nucleic acid. The liposomes can have a diameter of from 30 to 500 nanometers. The invention also provides a composition of a liposome in an aqueous medium with a nucleic acid and a lipid component present in a ratio of from 5 nmol lipid per microgram of the nucleic acid to 20, 30, 40, 50, 60, 70, 80, 90, or 100 nmol lipid per microgram of the nucleic acid. The methods and compositions can be used to deliver nucleic acids to cells for therapeutic purposes.

Problems solved by technology

Liposome technology has been developed and commercialized for the delivery of conventional pharmaceutical agents, but to date therapeutic nucleic acid containing liposomes have not been commercialized.

To date many publications demonstrate that liposome-plasmid DNA complexes can mediate efficient transient expression of a gene in cultured cells but poor in vivo transfection efficiencies.

Unlike viral vector preparations, liposome-nucleic acid complexes can have insufficient stability, and thus can be unsuitable for systemic injection.

In immunoliposomes however, amounts of cationic lipids that are effective to achieve such an effect can result in undesirable non-specific binding to cells, which decreases the ability to specifically direct a liposome-nucleic acid complex to a target cell or cell type.

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