title: A simple protocol for preparation of a liposomal vesicle with encapsulated plasmid DNA that mediate high accumulation and reporter gene activity in tumor tissue.
abstract: The systemic delivery of gene therapeutics by non-viral methods has proven difficult. Transfection systems that are performing well in vitro have been reported to have disadvantageous properties such as rapid clearance and short circulation time often resulting in poor transfection efficiency when applied in vivo. Large unilaminary vesicles (LUV) with encapsulated nucleic acids designated stabilized-plasmid-lipo-particle (SPLP) have showed promising results in terms of systemic stability and accumulation in tumor tissue due to the enhanced permeability and retention effect (EPR). We have developed a simple protocol for the research-scale preparation of SPLPs from commercially available reagents with high amounts of encapsulated plasmid DNA. The SPLPs show properties of promising accumulation in tumor tissue in comparison to other organs when intravenously injected into xenograft tumor-bearing nude mice. Although transcriptionally targeted suicide gene therapy was not achieved, the SPLPs were capable of mediating reporter gene transfection in subcutaneous flank tumors originating from human small cell lung cancer.
authors.affiliation: Department of Radiation Biology, section 6321, Finsen Center, Copenhagen University Hospital, Copenhagen, Denmark ; Department of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby, Denmark.
authors.forename: Torben
authors.initials: T
authors.lastname: Gjetting
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby, Denmark.
authors.forename: Thomas Lars
authors.initials: TL
authors.lastname: Andresen
authors.affiliation: Department of Radiation Biology, section 6321, Finsen Center, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: Camilla Laulund
authors.initials: CL
authors.lastname: Christensen
authors.affiliation: Department of Radiation Biology, section 6321, Finsen Center, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: Frederik
authors.initials: F
authors.lastname: Cramer
authors.affiliation: Department of Radiation Biology, section 6321, Finsen Center, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: Thomas Tuxen
authors.initials: TT
authors.lastname: Poulsen
authors.affiliation: Department of Radiation Biology, section 6321, Finsen Center, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: Hans Skovgaard
authors.initials: HS
authors.lastname: Poulsen
keywords: Biodistribution; EPR, Enhanced permeability and retention effect; Gene delivery; Liposome; PDI, Polydispersity index; PEG, Polyethylene glycol; SCD, Super cytosine deaminase; SCLC, Small cell lung carcinoma; SPLP, Stabilized plasmid–lipid particle; Stabilized plasmid–lipid particle (SPLP); Suicide gene therapy; Xenograft tumor model