In Vivo Delivery of Nucleic Acids to the Liver or Liver Tissue

Abstract

The invention encompasses methods of delivering nucleic acids, including dsRNA, to mammalian target cells in vivo via intercellular transfer, wherein the dsRNA is delivered to or expressed in a first cell different from the target cell, wherein the first cell facilitates delivery of the dsRNA to the target cell.

What is claimed: 
     
         1 . A method of delivering at least one initial nucleic acid to liver or liver tissue in an animal comprising:
 transfecting at least one muscle or skin cell of said animal with a nucleic acid wherein said transfection results in said nucleic acid being delivered to at least one cell in the liver or liver tissue.   
     
     
         2 . The method of  claim 1  wherein the muscle or skin cell is selected from the group consisting of fibroblast cells, cells in a dermal layer in the skin, cells in a subcutaneous layer of the skin, myocytes and myoblasts. 
     
     
         3 . The method of  claim 1  wherein the transfecting of the muscle cell is comprised of administering intramuscularly the nucleic acid. 
     
     
         4 . The method of  claim 1  wherein the transfecting of the skin cell is comprised of administering subcutaneously or intradermally the nucleic acid. 
     
     
         5 . The method of  claim 1  wherein the nucleic acid is a ribonucleic acid (RNA). 
     
     
         6 . The method of  claim 5  wherein the RNA is a double-stranded RNA (dsRNA) or a nucleic acid encoding said dsRNA. 
     
     
         7 . The method  claim 6  wherein one strand of said dsRNA is substantially complementary to a region of a messenger RNA transcribed by anendogenous target gene in the liver or liver tissue. 
     
     
         8 . The method of  claim 7  wherein the endogenous target gene in the liver or liver tissue regulates the production of cholesterol. 
     
     
         9 . The method of  claim 8  wherein the endogenous target gene is selected from the group consisting of APOB, pcsk9, and A1AT. 
     
     
         10 . The method of  claim 1  wherein said transfection is facilitated by one or more agents selected from the group consisting of polymer or peptide complexes, cationic amphiphiles, cationic lipids, cationic liposome formulations, a local anaesthetic, bupivacaine, particulates, gold particles, gene gun delivery, polycationic agents, cationic agents, spermine, spermine derivatives, spermidine, spermidine derivatives, cholesteryl spermine compounds, cholesteryl spermine carbamates, an electroporation-facilitating agent, poly-L-glutamate, electroporation, needle injection, needleless injection, and transdermal patch. 
     
     
         11 . The method of  claim 1  wherein said transfected cells further express a transmembrane or surface ligand specific for a receptor on the liver or liver tissue. 
     
     
         12 . The method of  claim 11  wherein a second nucleic acid expressing said transmembrane or surface ligand is co-transfected with said initial nucleic acid 
     
     
         13 . The method of  claim 12  wherein said nucleic acid expressing said transmembrane or surface ligand and said initial nucleic acid are encoded on a single vector or plasmid. 
     
     
         14 . The method of  claim 1  wherein said nucleic acid is a dsRNA having between 15 to about 50 base pairs. 
     
     
         15 . The method of  claim 14  wherein the dsRNA an shRNA or an siRNA 
     
     
         16 . The method of  claim 1  wherein said transfection of said nucleic acid to said muscle or skin cell does not trigger a detectable PKR response.