Sterically stabilized BGTC-based lipoplexes: structural features and gene transfection into the mouse airways in vivo.
BACKGROUND
Colloidal stability of lipid/DNA aggregates is a major requirement for cationic lipid-mediated transfection which is particularly difficult to fulfil at the high DNA concentrations used for in vivo gene delivery. Thus, we have investigated the potential of poly(ethyleneglycol) (PEG) conjugates for steric stabilization of lipoplexes formed by bis(guanidinium)-tren-cholesterol/dioleoyl phosphatidylethanolamine (BGTC/DOPE) liposomes, a class of cationic liposomes we have developed over the past few years.


RESULTS
We demonstrate that adequate lipophilic PEG derivatives can stabilize BGTC/DOPE lipoplexes formed at high DNA concentration. We also report the results of cryotransmission electron microscopy studies indicating that PEG-stabilized lipoplexes form DNA-coated structures which assemble into clusters exhibiting various complex morphologies. Finally, we report data from in vivo transfection experiments suggesting that PEG-mediated colloidal stabilization of concentrated lipoplex solutions may allow enhanced transfection of the mouse airways via intranasal administration.


CONCLUSIONS
Our results represent an important step towards the design of multimodular BGTC-based systems for improved in vivo gene transfection.
Pitard
B
B
UMR 7001, CNRS/ENSCP/Aventis Gencell, Vitry-sur-Seine, France. bruno.pitard@nantes.inserm.fr
Oudrhiri
N
N
Lambert
O
O
Vivien
E
E
Masson
C
C
Wetzer
B
B
Hauchecorne
M
M
Scherman
D
D
Rigaud
J L
JL
Vigneron
J P
JP
Lehn
J M
JM
Lehn
P
P
D000818:Animals; D002470:Cell Survival; D002701:Chloramphenicol / Q000031:analogs & derivatives* / Q000378:metabolism; D002784:Cholesterol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004247:DNA / Q000737:chemistry / Q000648:ultrastructure; D005260:Female; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D020404:Glycerophospholipids / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D006146:Guanidines / Q000737:chemistry / Q000378:metabolism; D008168:Lung / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D010714:Phosphatidylethanolamines; D011092:Polyethylene Glycols / Q000737:chemistry; D014162:Transfection; D014407:Tumor Cells, Cultured
C410262:1,2-dioleoyl-glycero-3-phosphatidyl ethanolamine; C101389:3-(N(4)-(N(1),N(8)-diguanidinospermidine)carbamoyl)cholesterol; D020404:Glycerophospholipids; D006146:Guanidines; D010714:Phosphatidylethanolamines; C026822:chloramphenicol 3-acetate; D011092:Polyethylene Glycols; D002701:Chloramphenicol; D004247:DNA; D002784:Cholesterol