Use of sterically stabilized cationic liposomes to efficiently deliver cpg oligonucleotides in vivo

Abstract

Sterically stabilized cationic liposomes (SSCL) encapsulating a K type oligodeoxynucleotide (ODN) including a CpG motif are disclosed. These SSCL encapuslating a K type ODN can be used to effectively deliver the ODN to a cell. A novel method is also disclosed for producing the SSCL encapsulating the K type ODN. Administration of the SSCL encapsulating a K type ODN and a chemotherapeutic agent, such as a chimeric molecule comprising a targeting molecule selected from the group consisting of an IL-13, and an anti-IL-13 receptor antibody; and an effector molecule selected from the group consisting of a Pseudomonas exotoxin, a Diphtheria toxin, and a radionuclide, can be used to dramatically reduce the growth of solid tumors.

1 . A sterically stabilized cationic liposome composition, comprising
 a cationic lipid, and a co-lipid, a stabilizing agent encapsulating an oligodeoxynucleotide of at least ten nucleotides in length comprising a CpG motif, wherein the oligodexoynucleotide comprising the CpG motif comprises a sequence represented by the formula 5′ N 1 N 2 N 3 Q-CpG-WN 4 N 5 N 6  3′ (SEQ ID NO: 97), wherein Q is a T, G, or A, W is A or T, and N 1 , N 2 , N 3 , N 4 , N 5 , and N 6  are any nucleotide, and wherein the lipid:co-lipid ratio is about 4:6, and wherein the stabilizing agent comprises about 1 percent to about 5 percent of the co-lipid composition.   
     
     
         2 . The sterically stabilized cationic liposome composition of  claim 1 , wherein the lipid is a cholesterol. 
     
     
         3 . The sterically stabilized cationic liposome composition of  claim 1 , wherein the cholesterol is dimethyaminoethane-carbamol-cholesterol. 
     
     
         4 . The sterically stabilized cationic liposome composition of  claim 1 , wherein the co-lipid is a phosphitidyl ethanolamine. 
     
     
         5 . The sterically stabilized cationic liposome composition of  claim 4 , wherein the phosphitidyl ethanolamine is dioleyl phosphatidyl ethanolamine. 
     
     
         6 . The sterically stabilized cationic liposome composition of  claim 1 , wherein the stabilizing agent is a polyethylene glycol. 
     
     
         7 . The sterically stabilized cationic liposome composition of  claim 6 , wherein the polyethylene glycol is polyethylene glycol-phosphatidyl ethanolamine. 
     
     
         8 . The sterically stabilized cationic liposome composition of  claim 3 , wherein the co-lipid is a dioleyl phosphitidyl ethanolamine, and the stabilizing agent is polyethylene glycol-phosphatidyl ethanolamine. 
     
     
         9 . The sterically stabilized cationic liposome composition of  claim 1 , further comprising an antigen. 
     
     
         10 . The sterically stabilized cationic liposome composition of  claim 10 , wherein the antigen is selected from the group consisting of a protein, a polypeptide, or a polysaccharide. 
     
     
         11 . The composition according to  claim 8 , wherein the sterically stabilized cationic liposome further comprises a targeting molecule. 
     
     
         12 . A pharmaceutical composition comprising a therapeutically effective amount of the sterically stabilized liposome composition of  claim 1  in a pharmaceutically acceptable carrier. 
     
     
         13 . A method for stimulating an immune response in a subject, comprising
 administering to the subject a therapeutically effective amount of the sterically stabilized cationic liposome composition of  claim 1 ,   thereby stimulating the immune response.   
     
     
         14 . The method of  claim 13 , wherein the immune response is expression of a cytokine. 
     
     
         15 . The method of  claim 15 , further comprising administering an antigen to the subject, thereby stimulating an antigen-specific immune response. 
     
     
         16 . The method of  claim 13 , wherein the subject is infected with an infectious agent. 
     
     
         17 . The method of  claim 16 , wherein the infectious agent is a fungus, bacteria, or a virus. 
     
     
         18 . The method of  claim 16 , further comprising administering to the subject a therapeutically effective amount of an anti-infectious agent. 
     
     
         19 . A method of stimulating an immune cell, comprising
 contacting the immune cell with the sterically stabilized cationic liposome composition of  claim 1 ,   thereby stimulating the immune cell.   
     
     
         20 . The method of  claim 19 , wherein the immune cell is in vitro. 
     
     
         21 . A method for inducing an immune response in a subject, comprising
 contacting immune cells from the subject in vitro with a therapeutically effective amount of the sterically stabilized cationic liposome composition of  claim 1 ;   contacting the immune cells with an antigen for a time sufficient to generate antigen specific immune cells; and   administering said antigen specific immune cells to the subject in an amount sufficient to induce an immune response.   
     
     
         22 . The method of  claim 18 , further comprising administering the antigen to the subject. 
     
     
         23 . The method of  claim 25 , wherein the anti-infectious agent is an antibiotic, an antiviral, or an anti-fungal agent. 
     
     
         24 . A method for producing the sterically stabilized cationic liposome of  claim 1 , comprising
 contacting a unilamellar vesicle with the oligodeoxynucleotide;   dehydrating the unilamellar vesicle and the oligodeoxynucleotide;   rehydrating the unilamellar vesicle and the oligodeoxynucleotide;   
       thereby producing the sterically stabilized cationic liposome encapsulating the oligodeoxynucleotide. 
     
     
         25 . The method of  claim 24 , further comprising extruding the sterically stabilized cationic liposome encapsulating the agent of interest to produce a liposome of a specified size. 
     
     
         26 . The method of  claim 25 , wherein the specified size is about 150 micrometers or less. 
     
     
         27 . The method of  claim 24 , wherein the unilamellar vesicle comprises the cationic lipid, the co-lipid, and the stabilizing agent. 
     
     
         28 . A method for impairing growth of a solid tumor cell bearing an IL-13 receptor in a subject, comprising
 administering to the subject a therapeutically effective amount of a chimeric molecule comprising a targeting molecule selected from the group consisting of an IL-13, and an anti-IL-13 receptor antibody; and an effector molecule selected from the group consisting of a  Pseudomonas  exotoxin, a  Diphtheria  toxin, and a chemotherapeutic agent, wherein the effector molecule is covalently linked to the targeting molecule or is linked to the targeting molecule by a linker; and   administering to the subject a therapeutically effective amount of the sterically stabilized cationic liposome composition of  claim 1 ,   
       thereby impairing the growth of the solid tumor. 
     
     
         29 . The method of  claim 28 , wherein the targeting molecule is IL-13. 
     
     
         30 . The method of  claim 28 , wherein the effector molecule is a  Pseudomonas  exotoxin, a radionuclide, or a  Diphtheria  toxin. 
     
     
         31 . The method of  claim 30 , wherein the effector molecule is a  Pseudomonas  exotoxin. 
     
     
         32 . The method of  claim 28 , wherein the targeting molecule is IL-13, wherein the effector molecule is  Pseudomonas  exotoxin, and wherein the lipid:co-lipid:stabilizing agent molar ratio of the sterically stabilized cationic liposome composition is 4:6:0.06, and wherein the lipid is dimethyaminoethane-carbamol-cholesterol, the co-lipid is dioleyl phosphatidyl ethanolamine, and the stabilizing agent is a polyethylene glycol: phosphatidyl ethanolamine. 
     
     
         33 . The method of  claim 32 , wherein the tumor is a head or neck carcinoma.