Intracellular delivery of siRNA by cell-penetrating peptides modified with cationic oligopeptides.

DDS Institute, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato, Tokyo 105-8461, Japan.
Drug Delivery (Impact Factor: 2.2). 05/2009; 16(3):153-9. DOI: 10.1080/10717540902722774
Source: PubMed

ABSTRACT To achieve the effective intracellular delivery of siRNA and silence specific genes, various types of conjugates between cell-penetrating peptides (CPPs; Transportan, Penetratin, Tat) and cationic peptides were developed. Uptake, intracellular localization, cytotoxicity, and biological activity of siRNA were significantly dependent on the kind of CPP used and the length of the cationic peptides in the conjugate. Transportan-based conjugates yielded both high internalization of siRNA and strong gene silencing activity, while Penetratin- and Tat-based conjugates did not. These different properties of CPPs emphasize the importance of careful peptide selection and design when attempting the application of CPP technology.

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