Search results for "gene transfer"
showing 10 items of 181 documents
Lokale Medikamentengabe und Gentherapie
1997
Eines der wichtigsten Probleme der klinischen Kardiologie, die Entwickung einer Restenose nach koronarer Ballonangioplastie, ist bisher noch nicht befriedigend gelöst. Die pathophysiologischen Erkenntnisse über die Mechanismen der Neointimabildung sind noch unvollständig, und zahlreiche Therapiestudien mit systemisch applizierten Pharmaka mit unterschiedlichem Wirkungsmechanismus sind fehlgeschlagen. Mögliche innovative Therapieansätze betreffen die hochdosierte lokale Substanzapplikation an der Dilatationsstelle und lokale gentherapeutische Eingriffe zur Verhinderung der Neointimabildung durch Proliferationshemmung der glatten Gefäßmuskelzellen. Zahlreiche Kathetermodelle sind entwickelt w…
Integration of Indocyanine Green Analogs as Near‐Infrared Fluorescent Carrier for Precise Imaging‐Guided Gene Delivery
2020
Codelivery of diagnostic probes and therapeutic molecules often suffers from intrinsic complexity and premature leakage from or degradation of the nanocarrier. Inspired by the "Y" shape of indocyanine green (ICG), the dye is integrated in an amphiphilic lipopeptide (RNF). The hydrophilic segment is composed of arginine-rich dendritic peptides, while cyanine dyes are modified with two long carbon chains and employed as the hydrophobic moiety. They are linked through a disulfide linkage to improve the responsivity in the tumor microenvironment. After formulation with other lipopeptides at an optimized ratio, the theranostic system (RNS-2) forms lipid-based nanoparticles with slight positive z…
A nitroreductase and glutathione responsive nanoplatform for integration of gene delivery and near-infrared fluorescence imaging
2020
A novel platform rationally integrating indocyanine green analogues and an arginine-rich dendritic peptide with both nitroreductase (NTR) and glutathione (GSH) reduction responsive linkers was developed. This multifunctional platform can enable selective and efficient gene delivery and specific turn-on fluorescence imaging in tumors.
Developments in the use of baculoviruses for the surface display of complex eukaryotic proteins
2001
The ability to couple genotype to phenotype has proven to be of immense value in systems such as phage display and has allowed genes encoding novel functions to be selected directly from complex libraries. However, the complexity of many eukaryotic proteins places a severe constraint on successful display in Escherichia coli. This restriction could be resolved if a eukaryotic virus could be similarly engineered for display purposes. Preliminary data have suggested that the baculovirus Autographa californica, a multiple nuclear polyhedrosis virus (AcMNPV) is a candidate for eukaryotic virus display because the insertion of peptides into the native virus coat protein, or the expression of for…
Alternative assay procedures for cytokines and soluble receptors of the IL-6 family.
1996
Human hepatoma cells (HepG2 cells) were transfected with expression vectors for human IL-6 (hIL-6) and rat IL-6R (rIL-6-R). The cell lines were used for testing the biological activity of different IL-6 species, soluble hIL-6R (shIL-6R) and some members of the IL-6 cytokine family by means of an ELISA procedure. The assay is based on induction of the gene expression of the acute phase protein haptoglobin in hepatoma cells and provides an alternative bioassay taking advantage of the hepatocyte stimulatory activity of IL-6 (as opposed to the B9 proliferative assay). A dose-response experiment with IL-6 showed that half-maximal stimulation was achieved with approx. 5 ng/ml of hIL-6 in HepG2 ce…
Pharmacodynamic approach to study the gene transfer process employing non-viral vectors
2000
Abstract In the present work we set out to apply pharmacodynamic concepts derived from dose–response curves (Potency and Efficacy) to characterize the gene transfer efficiency of a vector:DNA complex. We employed two widely used vectors, the cationic lipid DOTAP (N,N,N-trimethyl 1-2-3-bis (1-oxo-9-octa-decenyl)oxy-(Z,Z)-1-propanaminium methyl sulfate) and the cationic polymer PEI (polyethylenimine, 800 kDa) to transfect several constructions of the green fluorescent protein cDNA. The analysis of dose–response curves indicated that in all cases the goodness-of-fit was > 0.99. Potency is a measure that provides information on gene activity per amount of DNA. Efficacy is a measure of maximum g…
Structure and evolution of the leucine plasmids carried by the endosymbiont (Buchnera aphidicola) from aphids of the family Aphididae.
1998
In all examined species of the family Aphididae, the bacterial endosymbiont Buchnera aphidicola carries a plasmid encoding the genes leuABCD (involved in leucine biosynthesis) along with repA1, repA2 and ORF1. The gene organisation of the leucine plasmids was conserved, except in Buchnera isolated from Pterocomma populeum, where ORF1 was located in a different position. An inverted repeat (LIR1) located between repA2 and leuA is found in all of the Buchnera leucine plasmids examined. The predicted secondary structure of the LIR1 transcript conforms to a long hairpin loop, suggesting an involvement in transcription termination or messenger stability. Phylogenetic reconstruction based on repA…
Highly efficient liposome-mediated gene transfer of inducible nitric oxide synthase in vivo and in vitro in vascular smooth muscle cells.
2000
Objective: The efficient introduction of regulatory genes into vascular smooth muscle cells (SMCs) is one of the most promising options for gene therapy of cardiovascular diseases. Cationic liposome-mediated gene transfer may become a favorable transfection technique with regard to patient’s safety for in vivo administration. However, this method until now has its limitation in a low transfection efficiency. Therefore, the present study was designed to improve cationic liposome-mediated transfection of rabbit vascular SMCs in vitro and in vivo, in order to enhance transfection efficiency and present an optimized system which may offer a potential therapeutic benefit for in vivo application.…
In Vivo Gene-Silencing in Fibrotic Liver by siRNA-Loaded Cationic Nanohydrogel Particles
2015
Cationic nanohydrogel particles loaded with anti-Col1α1 siRNA suppress collagen synthesis and deposition in fibrotic mice: Systemically administered 40 nm sized nanogel particles accumulate in collagen-expressing cells in the liver. Their siRNA payload induces a sequence specific in vivo gene knockdown affording an efficient antifibrotic effect in mice with liver fibrosis.
Multifunctional Poly(ethylene glycol)s
2011
In the rapidly evolving multidisciplinary field of polymer therapeutics, tailored polymer structures represent the key constituent to explore and harvest the potential of bioactive macromolecular hybrid structures. In light of the recent developments for anticancer drug conjugates, multifunctional polymers are becoming ever more relevant as drug carriers. However, the potentially best suited polymer, poly(ethylene glycol) (PEG), is unfavorable owing to its limited functionality. Therefore, multifunctional linear copolymers (mf-PEGs) based on ethylene oxide (EO) and appropriate epoxide comonomers are attracting increased attention. Precisely engineered via living anionic polymerization and d…