title: PEGylation improves the receptor-mediated transfection efficiency of peptide-targeted, self-assembling, anionic nanocomplexes.
abstract: Non-viral vector formulations comprise typically complexes of nucleic acids with cationic polymers or lipids. However, for in vivo applications cationic formulations suffer from problems of poor tissue penetration, non-specific binding to cells, interaction with serum proteins and cell adhesion molecules and can lead to inflammatory responses. Anionic formulations may provide a solution to these problems but they have not been developed to the same extent as cationic formulations due to difficulties of nucleic acid packaging and poor transfection efficiency. We have developed novel PEGylated, anionic nanocomplexes containing cationic targeting peptides that act as a bridge between PEGylated anionic liposomes and plasmid DNA. At optimized ratios, the components self-assemble into anionic nanocomplexes with a high packaging efficiency of plasmid DNA. Anionic PEGylated nanocomplexes were resistant to aggregation in serum and transfected cells with a far higher degree of receptor-targeted specificity than their homologous non-PEGylated anionic and cationic counterparts. Gadolinium-labeled, anionic nanoparticles, administered directly to the brain by convection-enhanced delivery displayed improved tissue penetration and dispersal as well as more widespread cellular transfection than cationic formulations. Anionic PEGylated nanocomplexes have widespread potential for in vivo gene therapy due to their targeted transfection efficiency and ability to penetrate tissues.
authors.affiliation: Wolfson Centre for Gene Therapy of Childhood Disease, UCL Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK. Electronic address: a.tagalakis@ucl.ac.uk.
authors.forename: Aristides D
authors.initials: AD
authors.lastname: Tagalakis
authors.affiliation: Wolfson Centre for Gene Therapy of Childhood Disease, UCL Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK.
authors.forename: Gavin D
authors.initials: GD
authors.lastname: Kenny
authors.affiliation: Functional Neurosurgery Research Group, School of Clinical Sciences, AMBI Labs, University of Bristol, Southmead Hospital, Bristol BS10 5NB, UK.
authors.forename: Alison S
authors.initials: AS
authors.lastname: Bienemann
authors.affiliation: UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK.
authors.forename: David
authors.initials: D
authors.lastname: McCarthy
authors.affiliation: Wolfson Centre for Gene Therapy of Childhood Disease, UCL Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK.
authors.forename: Mustafa M
authors.initials: MM
authors.lastname: Munye
authors.affiliation: Functional Neurosurgery Research Group, School of Clinical Sciences, AMBI Labs, University of Bristol, Southmead Hospital, Bristol BS10 5NB, UK.
authors.forename: Hannah
authors.initials: H
authors.lastname: Taylor
authors.affiliation: Functional Neurosurgery Research Group, School of Clinical Sciences, AMBI Labs, University of Bristol, Southmead Hospital, Bristol BS10 5NB, UK.
authors.forename: Marcella J
authors.initials: MJ
authors.lastname: Wyatt
authors.affiliation: UCL Centre for Advanced Biological Imaging, Division of Medicine and Institute of Child Health, University College London, 72 Huntley Street, London, WC1E 6DD, UK.
authors.forename: Mark F
authors.initials: MF
authors.lastname: Lythgoe
authors.affiliation: Functional Neurosurgery Research Group, School of Clinical Sciences, AMBI Labs, University of Bristol, Southmead Hospital, Bristol BS10 5NB, UK.
authors.forename: Edward A
authors.initials: EA
authors.lastname: White
authors.affiliation: Wolfson Centre for Gene Therapy of Childhood Disease, UCL Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Hart
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism; D002460:Cell Line; D045744:Cell Line, Tumor; D003287:Contrast Media / Q000737:chemistry; D004247:DNA / Q000008:administration & dosage* / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry; D005682:Gadolinium / Q000737:chemistry; D006801:Humans; D008055:Lipids / Q000737:chemistry; D008081:Liposomes; D008297:Male; D051379:Mice; D053758:Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D010455:Peptides / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D012235:Rhodamines / Q000737:chemistry; D014162:Transfection / Q000379:methods*
chemical_list: D003287:Contrast Media; D005456:Fluorescent Dyes; D008055:Lipids; D008081:Liposomes; D010455:Peptides; D012235:Rhodamines; D011092:Polyethylene Glycols; D004247:DNA; D005682:Gadolinium
keywords: Anionic; Gene therapy; MRI; Nanoparticle; Self-assembling; Targeted