Efficient Delivery of Antisense Oligodeoxyribonucleotide G3139 by Human Serum Albumin-Coated Liposomes

Human serum albumin (HSA)-coated liposomal formulations were synthesized and evaluated for the delivery of antisense oligodeoxyribonucleotide (ODN) 63139 in KB human oral carcinoma cells. Liposomes composed of dimethyldioctadecylammonium bromide/egg phosphatidylcholine/alpha-tocopheryl polyethylene glycol 1000 succinate (58:40:2 molar ratio) complexed with G3139 and coated with HSA were investigated for Bcl-2 downregulating activity. Cellular uptake of HSA-coated liposome-ODN complexes was more efficient than the uncoated liposome-ODN complexes. Treatment of the cells with HSA-coated liposome-ODN complexes resulted in efficient Bcl-2 mRNA downregulation that was approximately 3-fold greater than with uncoated liposomes (p < 0.05) and 6-fold greater than with free ODN. The transfection efficiency of liposome-ODN complexes coated with HSA was dependent on the concentration of HSA used and on the contents of alpha-helix and beta-strand in HSA. HSA-coated liposomes are effective delivery vehicles for antisense ODN.