Addition of the influenza-derived dimeric peptide diINF-7 to LF2000/siRNA complexes had no effect on the particle size of ca. 120 nm, but significantly improved gene silencing activity of siRNAs targeting the epidermal growth factor receptor or the K-ras oncogene [196] . Similar results were obtained for plasmid delivery through addition of a fusogenic peptide derived from herpes simplex virus glycoprotein H to Lipofectamine/DNA complexes [197] . To the same end, Futaki et al. [198] used the peptide GALA, which was specially designed to mimic the function of viral fusion sequences, together with various commercially available cationic liposomes. Although they could not detect significant differences in cellular localization, plasmid transfection efficiency was increased and liposomal dosage could be reduced.