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ID: 219383.0, MPI für biophysikalische Chemie / Molekulare Biologie (Dr. Thomas M. Jovin)
New effects in polynucleotide release from cationic lipid carriers revealed by confocal imaging, fluorescence cross-correlation spectroscopy and single particle tracking
Authors:Berezhna, S.; Schaefer, S.; Heintzmann, R.; Jahnz, M.; Boese, G.; Deniz, A.; Schwille, P.
Date of Publication (YYYY-MM-DD):2005-05
Title of Journal:Biochimica et Biophysica Acta
Start Page:193
End Page:207
Sequence Number of Article:doi:10.1016/j.bbamem.2005.02.011
Review Status:not specified
Audience:Not Specified
Abstract / Description:We report on new insights into the mechanisms of short single and double stranded oligonucleotide release from cationic lipid complexes (lipoplexes), used in gene therapy. Specifically, we modeled endosomal membranes using giant unilamellar vesicles and investigated the roles of various individual cellular phospholipids in interaction with lipoplexes. Our approach uses a combination of confocal imaging, fluorescence cross-correlation spectroscopy and single particle tracking, revealing several new aspects of the release: (a) phosphatidylserine and phosphatidylethanolamine are equally active in disassembling lipoplexes, while phosphatidylcholine and sphingomyelin are inert; (b) in contrast to earlier findings, phosphatidylethanolamine alone, in the absence of anionic phosphatidylserine triggers extensive release; (c) a double-stranded DNA structure remains well preserved after release; (d) lipoplexes exhibited preferential binding to transient lipid domains, which appear at the onset of lipoplex attachment to originally uniform membranes and vanish after initiation of polynucleotide release. The latter effect is likely related to phosphatidyleserine redistribution in membranes due to lipoplex binding. Real time tracking of single DOTAP/DOPE and DOTAP/DOPC lipoplexes showed that both particles remained compact and associated with membranes up to 1–2 min before fusion, indicating that a more complex mechanism, different from suggested earlier rapid fusion, promotes more efficient transfection by DOTAP/DOPE complexes.
Free Keywords:lipoplex; endosomal membrane; release mechanism; giant unilamellar vesicles; fluorescence microscopy; single particle tracking
Last Change of the Resource (YYYY-MM-DD):2005-05-17
External Publication Status:published
Document Type:Article
Communicated by:N. N.
Affiliations:MPI für biophysikalische Chemie/Abt. Thomas Jovin / 060
MPI für biophysikalische Chemie/AG Petra Schwille
External Affiliations:Institute of Biophysics/Biotec, Dresden University of Technology, Tatzberg 47-51, 01307 Dresden, Germany; The Scripps Research Institute, Department of Molecular Biology, 10550 North Torrey Pines Road, MB-19, La Jolla, CA 92037, USA
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