Novel targeted liposomes deliver sirna to hepatocellular carcinoma cells in vitro.
Liposomes form a major class of non-viral vectors for short interfering RNA delivery, however tissue and cell-specific targeting are additional requirements in the design of short interfering RNA delivery systems with a therapeutic potential. Selective delivery of liposomes to hepatocytes may be achieved by directing complexes to the asialoglycoprotein receptor, which is expressed on hepatocytes, and which displays high affinity for the β-d-galactopyranosyl moiety. We aimed to show that the d-galactopyranosyl ring in direct β-glycosidic link to cholesterol, when formulated into liposomes with 3β[N-(N',N'-dimethylaminopropane) carbamoyl] cholesterol (Chol-T) or its quaternary trimethylammonium analogue (Chol-Q), may promote targeted delivery of cytotoxic short interfering RNA to the human hepatoma cell line HepG2 via the asialoglycoprotein receptor. Liposome-short interfering RNA interactions were characterized by electron microscopy, dye displacement, gel retardation and nuclease assays. Stable short interfering RNA-protective lipoplexes were formed at N/P ratios in the range 5:1-7:1. Targeted lipoplex 4 achieved high transfection efficiencies at 50 nm short interfering RNA (70%) and <10% in a competition assay, whilst untargeted complexes reached low levels at the same concentration (<25%). Transfection efficiencies of all lipoplexes in the asialoglycoprotein receptor-negative cell line HEK293 under the same conditions were low. Lipoplexes containing cholesteryl-β-d-galactopyranoside may therefore form the basis for the development of useful hepatotropic short interfering RNA delivery vectors.
Non-viral Gene Delivery Laboratory, Discipline of Biochemistry, University of KwaZulu-Natal, Westville campus, P. Bag X54001, Durban 4000, South Africa.
Shantal
S
Dorasamy
Nicolisha
N
Narainpersad
Moganavelli
M
Singh
Mario
M
Ariatti
D006528:Carcinoma, Hepatocellular / Q000235:genetics*; D016503:Drug Delivery Systems; D005690:Galactose / Q000737:chemistry* / Q000378:metabolism; D057809:HEK293 Cells; D056945:Hep G2 Cells; D022781:Hepatocytes / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008081:Liposomes / Q000737:chemistry* / Q000378:metabolism; D008113:Liver Neoplasms / Q000235:genetics*; D034741:RNA, Small Interfering / Q000008:administration & dosage*; D014162:Transfection
D008081:Liposomes; D034741:RNA, Small Interfering; D005690:Galactose