Nucleic acid ligand complexes

Abstract

This invention discloses a method for preparing a therapeutic or diagnostic complex comprised of a nucleic acid ligand and a lipophilic compound or non-immunogenic, high molecular weight compound by identifying a nucleic acid ligand by SELEX methodology and associating the nucleic acid ligand with a lipophilic compound or a non-immunogenic, high molecular weight compound. The invention further discloses complexes comprising one or more nucleic acid ligands in association with a lipophilic compound or non-immunogenic, high molecular weight compound.

1 . A method for improving the intracellular delivery of a Nucleic Acid Ligand comprising covalently linking said Nucleic Acid Ligand with a Lipophilic Compound or a Non-Immuogenic, High Molecular Weight Compound, wherein said Nucleic Acid Ligand has a specific binding affinity for a Target.  
     
     
         2 . The method of  claim 1  wherein said Nucleic Acid Ligand is identified from a Candidate Mixture of Nucleic Acids, said Nucleic Acid Ligand being a ligand of said Target, by the method comprising: 
 a) contacting the Candidate Mixture with the Target, wherein Nucleic Acids having an increased affinity to the Target relative to the Candidate Mixture may be partitioned from the remainder of the Candidate Mixture;  
 b) partitioning the increased affinity Nucleic Acids from the remainder of the Candidate Mixture; and  
 c) amplifying the increased affinity Nucleic Acids to yield a ligand-enriched mixture of Nucleic Acids, whereby Nucleic Acid Ligands of said Target are identified.  
 
     
     
         3 . The method of  claim 1  wherein said Non-Immunogenic, High Molecular Weight Compound is selected from the group consisting of polyethylene glycol, dextran, albumin, and magnetite.  
     
     
         4 . The method of  claim 3  wherein said Non-Immunogenic, High Molecular Weight Compound is polyethylene glycol.  
     
     
         5 . The method of  claim 1  wherein said Lipophilic Compound is selected from the group consisting of cholesterol, dialkyl glycerol and diacyl glycerol.  
     
     
         6 . The method of  claim 5  wherein said Lipophilic Compound is cholesterol.  
     
     
         7 . The method of  claim 5  wherein said Lipophilic Compound is dialkyl glycerol.  
     
     
         8 . The method of  claim 1  wherein said Lipophilic Compound is a Lipid Construct.  
     
     
         9 . The method of  claim 8  wherein the Lipid Construct is a Lipid Bilayer Vesicle.  
     
     
         10 . The method of  claim 9  wherein said Lipid Bilayer Vesicle is a Liposome.  
     
     
         11 . The method of  claim 10  wherein said Nucleic Acid Ligand is projecting from the exterior surface of said Liposome.  
     
     
         12 . The method of  claim 10  wherein said Liposome comprises phosphatidylethanolamine.  
     
     
         13 . The method of  claim 10  wherein said Liposome comprises negatively-charged lipids.  
     
     
         14 . The method of  claim 13  wherein said negatively-charged lipids are selected from the group consisting of phosphatidylglycerol and phosphatidylserine.  
     
     
         15 . The method of  claim 10  wherein said Liposome is pH sensitive.  
     
     
         16 . The method of  claim 15  wherein the net charge of said Liposome becomes increasingly negative as the pH is raised.  
     
     
         17 . The method of  claim 10 , which further comprises encapsulating an additional therapeutic or diagnostic agent within said Liposome.  
     
     
         18 . The method of  claim 10 , which further comprises attaching an additional therapeutic or diagnostic agent with said Nucleic Acid Ligand.  
     
     
         19 . The method of  claim 1  wherein said Nucleic Acid Ligand localizes said Lipophilic Compound or said Non-Immuogenic, High Molecular Weight Compound to a preselected location.  
     
     
         20 . The method of  claim 10  further comprising administering said Liposome to a patient in conjunction with a fusogen.  
     
     
         21 . The method of  claim 20  wherein said fusogen is selected from the group consisting of multivalent cations, free fatty acids, viral fusion proteins, short chain polyethylene glycols, lysolecithin, detergents and surfactants.  
     
     
         22 . A method for imaging a site expressing a Target in a patient, the method comprising: 
 covalently linking a Nucleic Acid Ligand with magnetite, wherein said Nucleic Acid Ligand has a specific binding affinity for said Target;    administering said Nucleic Acid Ligand associated with magnetite to a patient; and    performing nuclear magnetic resonance (NMR) imaging.