Improvement of peptide vectors for gene delivery with active targeting profiles for phosphatidylserine

A cationic peptide, Td3701, which was derived from factor VIII that has affinity with phosphatidylserine (PS), showed efficient transfection ability for cells that express PS on the cell surface. PS is exposed on tumor cell surfaces therefore we have focused on PS as the target molecule for tumor specific gene delivery. In this article, to improve transfection efficiency and specificity in targeting tumor cells, some amino acid residues of Td3701 were replaced. The resulting peptide, Td3717, shows higher transfection efficiency (more than 30 times that of Td3701). The transfection efficiency was dependent on the amount of PS on the cell surface, suggesting that Td3717 bound with plasmid DNA could recognize PS on the cell surface. Td3717 is expected to be useful as an efficient gene carrier molecule specific to PS-presenting tumor cells.