Tumor-targeted nanodelivery systems to improve early mri detection of cancer

Abstract

The present invention is in the fields of drug delivery, cancer treatment and diagnosis and pharmaceuticals. This invention provides a method of making antibody- or antibody fragment-targeted immunoliposomes for the systemic delivery of molecules to treat and image diseases, including cancerous tumors. The invention also provides immunoliposomes and compositions, as well as methods of imaging various tissues. The liposome complexes are useful for encapsulation of imaging agents, for example, for use in magnetic resonance imaging. The specificity of the delivery system is derived from the targeting antibodies or antibody fragments.

What is claimed is: 
     
         1 . A method of preparing an antibody- or antibody fragment-targeted cationic immunoliposome complex comprising:
 (a) preparing an antibody or antibody fragment;   (b) mixing said antibody or antibody fragment with a cationic liposome to form a cationic immunoliposome, wherein said antibody or antibody fragment is not chemically conjugated to said cationic liposome; and   (c) mixing said cationic immunoliposome with an imaging agent at a ratio in the range of about 1.0:10 to about 1.0:35 (mg imaging agent:μg liposome) to form said antibody- or antibody fragment-targeted-cationic immunoliposome complex.   
     
     
         2 . The method of  claim 1 , wherein an antibody is mixed with said cationic liposome. 
     
     
         3 . The method of  claim 1 , wherein an antibody fragment is mixed with said cationic liposome. 
     
     
         4 . The method of  claim 3 , wherein said antibody fragment is a single chain Fv fragment. 
     
     
         5 . The method of  claim 4 , wherein said antibody fragment is an anti-transferrin receptor single chain Fv (TfRscFv). 
     
     
         6 . The method of  claim 1 , wherein said antibody or antibody fragment is an anti-HER-2 antibody or antibody fragment. 
     
     
         7 . The method of  claim 1 , wherein said antibody fragment comprises a cysteine moiety at a carboxy terminus prior to being mixed with said cationic liposome. 
     
     
         8 . The method of  claim 1 , further comprising mixing said cationic immunoliposome with a peptide comprising the K[K(H)KKK] 5 -K(H)KKC(HOKC) (SEQ ID NO: 1) peptide. 
     
     
         9 . The method of  claim 1 , wherein said cationic liposome comprises a mixture of one or more cationic lipids and one or more neutral or helper lipids. 
     
     
         10 . The method of  claim 1 , wherein said antibody or antibody fragment is mixed with said cationic liposome at a ratio in the range of about 1:20 to about 1:40 (w:w). 
     
     
         11 . The method of  claim 1 , wherein said cationic liposome comprises a mixture of dioleoyltrimethylammonium phosphate with dioleoylphosphatidylethanolamine and/or cholesterol; or a mixture of dimethyldioctadecylammonium bromide with dioleoylphosphatidylethanolamine and/or cholesterol. 
     
     
         12 . The method of  claim 1 , wherein said cationic immunoliposome is mixed with said imaging agent at a ratio of about 1:14 to about 1:28 (mg imaging agent:μg liposome). 
     
     
         13 . The method of  claim 1 , wherein said cationic immunoliposome is mixed with said imaging agent at a molar ratio of about 1:21 (mg imaging agent:μg liposome). 
     
     
         14 . The method of  claim 1 , wherein said imaging agent is a magnetic resonance imaging (MRI) agent, a computed tomography (CT) imaging agent, or a positron emission tomography (PET) imaging agent. 
     
     
         15 . The method of  claim 14 , wherein said MRI agent is gadopentetate dimeglumine, iron oxide, or iopamidol, said CT imaging agent is barium, iodine or saline, or said PET imaging agent is  18 F-2-deoxy-2-fluoro-D-glucose (FDG). 
     
     
         16 . A cationic immunoliposome complex prepared by the method of  claim 1 .