title: Reduction-sensitive liposomes from a multifunctional lipid conjugate and natural phospholipids: reduction and release kinetics and cellular uptake.
abstract: The development of targeted and triggerable delivery systems is of high relevance for anticancer therapies. We report here on reduction-sensitive liposomes composed of a novel multifunctional lipidlike conjugate, containing a disulfide bond and a biotin moiety, and natural phospholipids. The incorporation of the disulfide conjugate into vesicles and the kinetics of their reduction were studied using dansyl-labeled conjugate 1 in using the dansyl fluorescence environmental sensitivity and the Förster resonance energy transfer from dansyl to rhodamine-labeled phospholipids. Cleavage of the disulfide bridge (e.g., by tris(2-carboxyethyl)phosphine (TCEP), dithiothreitol (DTT), l-cysteine, or glutathione (GSH)) removed the hydrophilic headgroup of the conjugate and thus changed the membrane organization leading to the release of entrapped molecules. Upon nonspecific uptake of vesicles by macrophages, calcein release from reduction-sensitive liposomes consisting of the disulfide conjugate and phospholipids was more efficient than from reduction-insensitive liposomes composed only of phospholipids. The binding of streptavidin to the conjugates did not interfere with either the subsequent reduction of the disulfide bond of the conjugate or the release of entrapped molecules. Breast cancer cell line BT-474, overexpressing the HER2 receptor, showed a high uptake of the reduction-sensitive doxorubicin-loaded liposomes functionalized with the biotin-tagged anti-HER2 antibody. The release of the entrapped cargo inside the cells was observed, implying the potential of using our system for active targeting and delivery.
authors.affiliation: Institute of Biology/Molecular Biophysics, Humboldt-University Berlin, Invalidenstrasse 42, 10115 Berlin, Germany.
authors.forename: Björn
authors.initials: B
authors.lastname: Goldenbogen
authors.forename: Nicolai
authors.initials: N
authors.lastname: Brodersen
authors.forename: Andrea
authors.initials: A
authors.lastname: Gramatica
authors.forename: Martin
authors.initials: M
authors.lastname: Loew
authors.forename: Jürgen
authors.initials: J
authors.lastname: Liebscher
authors.forename: Andreas
authors.initials: A
authors.lastname: Herrmann
authors.forename: Holger
authors.initials: H
authors.lastname: Egger
authors.forename: Bastian
authors.initials: B
authors.lastname: Budde
authors.forename: Anna
authors.initials: A
authors.lastname: Arbuzova
mesh_terms: D001710:Biotin / Q000737:chemistry / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism*; D045744:Cell Line, Tumor; D004220:Disulfides / Q000737:chemistry / Q000378:metabolism; D004317:Doxorubicin / Q000493:pharmacokinetics*; D016503:Drug Delivery Systems; D005260:Female; D005452:Fluoresceins / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008055:Lipids / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry / Q000378:metabolism* / Q000493:pharmacokinetics*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D008856:Microscopy, Fluorescence; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010316:Particle Size; D013499:Surface Properties; D014018:Tissue Distribution
chemical_list: D004220:Disulfides; D005452:Fluoresceins; D008055:Lipids; D008081:Liposomes; D001710:Biotin; D004317:Doxorubicin; C007740:fluorexon