In vitro and in vivo characterization of CPP and transferrin modified liposomes encapsulating pDNA.

The limitations imposed on brain therapy by the blood–brain barrier (BBB) have warranted the development of carriers that can overcome and deliver therapeutic agents into the brain. We strategically designed liposomal nanoparticles encasing plasmid DNA for efficient transfection and translocation across the in vitro BBB model as well as in vivo brain-targeted delivery. Liposomes were surface modified with two ligands, cell-penetrating peptide (PFVYLI or R9F2) for enhanced internalization into cells and transferrin (Tf) ligand for targeting transferrin-receptor expressed on brain capillary endothelial cells. Dual-modified liposomes encapsulating pDNA demonstrated significantly (P < 0.05) higher in vitro transfection efficiency compared to single-modified nanoparticles. R9F2Tf-liposomes showed superior ability to cross in vitro BBB and, subsequently, transfect primary neurons. Additionally, these nanoparticles crossed in vivo BBB and reached brain parenchyma of mice (6.6%) without causing tissue damage. Transferrin receptor-targeting with enhanced cell penetration is a relevant strategy for efficient brain-targeted delivery of genes. Dual-modified liposomes surface modified with cell-penetrating peptides (PFVYLI and R9F2) and transferrin ligand were designed to overcome the blood brain barrier and efficiently deliver a plasmid DNA into the brain of mice. Our results showed the superior ability of R9F2Tf-liposomes to translocate across the in vitro blood brain barrier model and transfect neuronal cells as well as enhanced in vivo brain-targeted delivery properties. Thus, R9F2Tf-liposomes have potential as a carrier for brain-targeted gene delivery. Unlabelled Image [ABSTRACT FROM AUTHOR]