title: Glycosaminoglycan-resistant and pH-sensitive lipid-coated DNA complexes produced by detergent removal method.
abstract: Cationic polymers are efficient gene delivery vectors in in vitro conditions, but these carriers can fail in vivo due to interactions with extracellular polyanions, i.e. glycosaminoglycans (GAG). The aim of this study was to develop a stable gene delivery vector that is activated at the acidic endosomal pH. Cationic DNA/PEI complexes were coated by 1,2-dioleylphosphatidylethanolamine (DOPE) and cholesteryl hemisuccinate (CHEMS) (3:2 mol/mol) using two coating methods: detergent removal and mixing with liposomes prepared by ethanol injection. Only detergent removal produced lipid-coated DNA complexes that were stable against GAGs, but were membrane active at low pH towards endosome mimicking liposomes. In relation to the low cellular uptake of the coated complexes, their transfection efficacy was relatively high. PEGylation of the coated complexes increased their cellular uptake but reduced the pH-sensitivity. Detergent removal was thus a superior method for the production of stable, but acid activatable, lipid-coated DNA complexes.
authors.affiliation: Centre for Drug Research, University of Helsinki, P.O. Box 56, 00014 University of Helsinki, Finland. julia.lehtinen@helsinki.fi
authors.forename: Julia
authors.initials: J
authors.lastname: Lehtinen
authors.forename: Zanna
authors.initials: Z
authors.lastname: Hyvönen
authors.forename: Astrid
authors.initials: A
authors.lastname: Subrizi
authors.forename: Heike
authors.initials: H
authors.lastname: Bunjes
authors.forename: Arto
authors.initials: A
authors.lastname: Urtti
mesh_terms: D000818:Animals; D000838:Anions; D002417:Cattle; D002460:Cell Line; D002788:Cholesterol Esters / Q000737:chemistry; D004247:DNA / Q000008:administration & dosage* / Q000235:genetics; D003902:Detergents / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry*; D004355:Drug Stability; D018014:Gene Transfer Techniques; D006025:Glycosaminoglycans / Q000378:metabolism*; D000882:Haplorhini; D006863:Hydrogen-Ion Concentration; D007097:Imines / Q000737:chemistry; D008055:Lipids / Q000737:chemistry*; D008081:Liposomes; D010316:Particle Size; D010714:Phosphatidylethanolamines / Q000737:chemistry; D010957:Plasmids; D011095:Polyethylenes / Q000737:chemistry; D014162:Transfection
chemical_list: D000838:Anions; D002788:Cholesterol Esters; D003902:Detergents; D004337:Drug Carriers; D006025:Glycosaminoglycans; D007097:Imines; D008055:Lipids; D008081:Liposomes; D010714:Phosphatidylethanolamines; D011095:Polyethylenes; C505405:poly(ethylene imine); C020888:1,2-dielaidoylphosphatidylethanolamine; D004247:DNA; C427203:calf thymus DNA; C013440:cholesteryl succinate