Novel liposomal formulation for targeted gene delivery.
OBJECTIVE
Development of a polyethylene glycol (PEG)-stabilized immunoliposome (PSIL) formulation with high DNA content suitable for in vivo intravenous administration and targeted gene delivery.


METHODS
Plasmid DNA was condensed using 40% ethanol and packaged into neutral PSILs targeted to the mouse transferrin receptor using monoclonal antibodies (MAbs; clones RI7 and 8D3) attached to their PEG maleimide moieties. PSILs size was measured by quasi-elastic light scattering. The targeting capacity of the formulation was determined by transfection of mouse neuroblastoma Neuro 2A (N2A) cells with PSIL-DNA complexes conjugated with either RI7 or 8D3 MAbs.


RESULTS
DNA encapsulation and MAb conjugation efficiencies averaged 71 +/- 14% and 69 +/- 5% (mean +/- SD), respectively. No alteration in mean particle size (< 100 nm) or DNA leakage were found after 48 h storage in a physiological buffer, and the in vivo terminal half-life reached 23.9 h, indicating that the PSIL-DNA formulation was stable. Addition of free RI7 MAbs prevented transfection of N2A cells with PSIL-DNA complexes conjugated with either RI7 or 8D3 MAbs, confirming that the transfection was transferrin receptor-dependent.


CONCLUSIONS
The present data suggest that our new PSIL formulation combines molecular features required for targeted gene therapy including high DNA encapsulation efficiencies and vector-specific transient transfection capacity.
Rivest
Véronique
V
Molecular Endocrinology and Oncology Research Center, Centre Hospitalier de l'Université Laval (CHUL) Research Center, 2705 Laurier Blvd, Quebec, QC, Canada, G1V 4G2.
Phivilay
Alix
A
Julien
Carl
C
Bélanger
Sandra
S
Tremblay
Cyntia
C
Emond
Vincent
V
Calon
Frédéric
F
D000818:Animals; D000911:Antibodies, Monoclonal / Q000235:genetics / Q000276:immunology / Q000493:pharmacokinetics; D045744:Cell Line, Tumor; D002784:Cholesterol / Q000737:chemistry; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004339:Drug Compounding / Q000379:methods / Q000639:trends; D018390:Gene Targeting / Q000379:methods* / Q000639:trends; D005822:Genetic Vectors / Q000737:chemistry / Q000235:genetics* / Q000493:pharmacokinetics; D006207:Half-Life; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008081:Liposomes / Q000737:chemistry*; D051379:Mice; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D010713:Phosphatidylcholines / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011990:Receptors, Transferrin / Q000235:genetics / Q000276:immunology; D013696:Temperature; D013997:Time Factors; D014162:Transfection / Q000379:methods
D000911:Antibodies, Monoclonal; D008081:Liposomes; D010713:Phosphatidylcholines; D011990:Receptors, Transferrin; D011092:Polyethylene Glycols; D004247:DNA; D002784:Cholesterol; C028694:1-palmitoyl-2-oleoylphosphatidylcholine