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4. Increased Cellular Uptake of ApoE3- or c(RGD)-Modified Liposomes for Glioblastoma Therapy Depending on the Target Cells.

Author

Lubitz, Larissa J., Haffner, Moritz P., Rieger, Harden, and Leneweit, Gero

Subjects
NEUROLOGICAL disorders, DRUGS, THERAPEUTIC use of proteins, PEPTIDES, ENDOTHELIAL cells, LIPOSOMES
Abstract

As effective treatment of glioblastoma is still an unmet need, targeted delivery systems for efficient treatment are of utmost interest. Therefore, in this paper, surface modifications with a small peptide c(RGD) or physiological protein (ApoE3) were investigated. Cellular uptake in murine endothelial cells (bEnd.3) and different glioma cells (human U-87 MG, rat F98) was tested to elucidate possible differences and to correlate the uptake to the receptor expression. Different liposomal formulations were measured at 1 and 3 h for three lipid incubation concentrations. We calculated the liposomal uptake saturation S and the saturation half-time t1/2. An up to 9.6-fold increased uptake for ApoE3-modified liposomes, primarily in tumor cells, was found. Contrarily, c(RGD) liposomes showed a stronger increase in uptake in endothelial cells (up to 40.5-fold). The uptake of modified liposomes revealed enormous differences in S and t1/2 when comparing different tumor cell lines. However, for ApoE3-modified liposomes, we proved comparable saturation values (~25,000) for F98 cells and U-87 MG cells despite a 6-fold lower expression of LRP1 in F98 cells and a 5-fold slower uptake rate. Our findings suggest that cellular uptake of surface-modified liposomes depends more on the target structure than the ligand type, with significant differences between cell types of different origins. [ABSTRACT FROM AUTHOR]

Published
2024
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5. Elevated Cellular Uptake of Succinimide- and Glucose-Modified Liposomes for Blood–Brain Barrier Transfer and Glioblastoma Therapy.

Author

Lubitz, Larissa J., Haffner, Moritz P., Rieger, Harden, and Leneweit, Gero

Subjects
SUCCINIMIDES, LIPOSOMES, BRAIN cancer, TARGETED drug delivery, ENDOTHELIAL cells
Abstract

The uptake of four liposomal formulations was tested with the murine endothelial cell line bEnd.3 and the human glioblastoma cell line U-87 MG. All formulations were composed of DPPC, cholesterol, 5 mol% of mPEG (2000 Da, conjugated to DSPE), and the dye DiD. Three of the formulations had an additional PEG chain (nominally 5000 Da, conjugated to DSPE) with either succinimide (NHS), glucose (PEG-bound at C-6), or 4-aminophenyl β-D-glucopyranoside (bound at C-1) as ligands at the distal end. Measuring the uptake kinetics at 1 h and 3 h for liposomal incubation concentrations of 100 µM, 500 µM, and 1000 µM, we calculated the liposomal uptake saturation S and the saturation half-time t1/2. We show that only succinimide has an elevated uptake in bEnd.3 cells, which makes it a very promising and so far largely unexplored candidate for BBB transfer and brain cancer therapies. Half-times are uniform at low concentrations but diversify for high concentrations for bEnd.3 cells. Contrary, U-87 MG cells show almost identical saturations for all three ligands, making a uniform uptake mechanism likely. Only mPEG liposomes stay at 60% of the saturation for ligand-coated liposomes. Half-times are diverse at low concentrations but unify at high concentrations for U-87 MG cells. [ABSTRACT FROM AUTHOR]

Published
2024
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12. Regulation of the innate immune system by fragmented heparin-conjugated lipids on lipid bilayered membranes in vitro

Author

Adler, Anna, Fritsch, Marlene, Fromell, Karin, Leneweit, Gero, Ekdahl, Kristina N., Nilsson, Bo, Teramura, Yuji, Adler, Anna, Fritsch, Marlene, Fromell, Karin, Leneweit, Gero, Ekdahl, Kristina N., Nilsson, Bo, and Teramura, Yuji

Abstract

Surface modification with heparin is a powerful biomaterial coating strategy that protects against innate immunity activation since heparin is a part of the proteoglycan heparan sulfate on cell surfaces in the body. We studied the heparinization of cellular and material surfaces via lipid conjugation to a heparin-binding peptide. In the present study, we synthesized fragmented heparin (fHep)-conjugated phospholipids and studied their regulation of the innate immune system on a lipid bilayered surface using liposomes. Liposomes have versatile applications, such as drug-delivery systems, due to their ability to carry a wide range of molecules. Owing to their morphological similarity to cell membranes, they can also be used to mimic a simple cell-membrane to study protein–lipid interactions. We investigated the interaction of complement-regulators, factor H and C4b-binding protein (C4BP), as well as the coagulation inhibitor antithrombin (AT), with fHep-lipids on the liposomal surface. Herein, we studied the ability of fHep-lipids to recruit factor H, C4BP, and AT using a quartz crystal microbalance with dissipation monitoring. With dynamic light scattering, we demonstrated that liposomes could be modified with fHep-lipids and were stable up to 60 days at 4 °C. Using a capillary western blot-based method (Wes), we showed that fHep-liposomes could recruit factor H in a model system using purified proteins and assist in the degradation of the active complement protein C3b to iC3b. Furthermore, we found that fHep-liposomes could recruit factor H and AT from human plasma. Therefore, the use of fHep-lipids could be a potential coating for liposomes and cell surfaces to regulate the immune system on the lipid surface., Title in the list of papers of Anna Adler's thesis: Regulation of innate immune system by fragmented heparin-conjugated lipids on lipid bilayer membranes

Published
2023
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23. Effect of mistletoe preparations on cell migration: exploration of 3D experimental models

Author

Scheer, Rainer, Alban, Susanne, Becker, Hans, Beer, André-Michael, Blaschek, Wolfgang, Klein, Reinhild, Kreis, Wolfgang, Leneweit, Gero, Matthes, Harald, Spahn, Günther, Spange, Rainer, Scheer, R ( Rainer ), Alban, S ( Susanne ), Becker, H ( Hans ), Beer, A ( André-Michael ), Blaschek, W ( Wolfgang ), Klein, R ( Reinhild ), Kreis, W ( Wolfgang ), Leneweit, G ( Gero ), Matthes, H ( Harald ), Spahn, G ( Günther ), Spange, R ( Rainer ), Dolder, Alexandra, Avilla-Royo, Eva; https://orcid.org/0000-0002-1002-8491, Weissenstein, U, Baumgartner, Stephan, Simona, Benjamin R, Ehrbar, M; https://orcid.org/0000-0003-2707-4870, Simões-Wüst, Ana Paula; https://orcid.org/0000-0002-4489-0952, Scheer, Rainer, Alban, Susanne, Becker, Hans, Beer, André-Michael, Blaschek, Wolfgang, Klein, Reinhild, Kreis, Wolfgang, Leneweit, Gero, Matthes, Harald, Spahn, Günther, Spange, Rainer, Scheer, R ( Rainer ), Alban, S ( Susanne ), Becker, H ( Hans ), Beer, A ( André-Michael ), Blaschek, W ( Wolfgang ), Klein, R ( Reinhild ), Kreis, W ( Wolfgang ), Leneweit, G ( Gero ), Matthes, H ( Harald ), Spahn, G ( Günther ), Spange, R ( Rainer ), Dolder, Alexandra, Avilla-Royo, Eva; https://orcid.org/0000-0002-1002-8491, Weissenstein, U, Baumgartner, Stephan, Simona, Benjamin R, Ehrbar, M; https://orcid.org/0000-0003-2707-4870, and Simões-Wüst, Ana Paula; https://orcid.org/0000-0002-4489-0952

Published
2020

25. Liposomes with asymmetric bilayers produced from inverse emulsions for nucleic acid delivery

Author

de Matos, Maria, Miranda, Bárbara S, Rizky Nuari, Yudha, Storm, Gert, Leneweit, Gero, Schiffelers, Raymond M, Kok, Robbert J, Afd Pharmaceutics, Pharmaceutics, Afd Pharmaceutics, and Pharmaceutics

Subjects
Squalene, Biocompatibility, Lipid bilayers, asymmetric vesicles, Dispersity, Pharmaceutical Science, 02 engineering and technology, 03 medical and health sciences, 0302 clinical medicine, Nucleic Acids, Monolayer, Journal Article, Lipid bilayer, Phospholipids, Fluorescent Dyes, Liposome, Chemistry, siRNA encapsulation, Phosphatidylethanolamines, Bilayer, water-in-oil emulsification, 021001 nanoscience & nanotechnology, 4-Chloro-7-nitrobenzofurazan, Chemical engineering, 030220 oncology & carcinogenesis, Liposomes, Phosphatidylcholines, Nucleic acid, Nanoparticles, phase transfer, lipids (amino acids, peptides, and proteins), Emulsions, Nanocarriers, 0210 nano-technology
Abstract

Asymmetrical lipid nanoparticles are interesting nanocarriers for charged molecules, like nucleic acids. They promise control over inner and outer charge. High charge density on the inside is favourable for efficient condensation and charge neutralisation of highly charged biopharmaceuticals, while a neutral or slightly negative outer layer promotes biocompatibility. The main goal of this work was the development and characterisation of asymmetric liposomes, prepared using water-in-oil (w/o) nanoemulsions of phospholipids (PLs) and squalene in a centrifugal field. This method enables the control over the lipid composition of each monolayer. Liposomes were prepared by passing PL w/o nanoemulsions through an oil-water interface previously saturated with PLs. We used N-(7-Nitrobenz-2-Oxa-1,3-Diazol-4-yl)-1,2-Dihexadecanoyl-sn-Glycero-3-Phosphoethanolamine (NBD-PE) or N-(7-Nitrobenz-2-Oxa-1,3-Diazol-4-yl)-1,2-Dihexadecanoyl-sn-Glycero-3- phosphocholine (NBD-PC) as a fluorescent marker for either the inner or outer lipid layer and plasmid DNA (pDNA) as nucleic acid payload. The final liposomes had sizes below 200 nm and polydispersity indexes of 0.3 and had a bilayer asymmetry of 70%, thus shielding the charge of positive PLs in the inner bilayer leaflet. Final formulations were examined using negative staining transmission electron microscopy (TEM). Plasmid encapsulation efficiency of the method was 10-15%. Our results indicate that the w/o nanoemulsion-centrifugation method allows the successful production of liposomes with tailored features for encapsulation of nucleic acid therapeutics.

Published
2019
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26. Colloidal formulation of mistletoe extracts in a pharmaceutical flow process for targeted cancer therapy

Author

Leneweit, Gero, Miranda, Bárbara S., de Matos, Maria B.C., Beztsinna, Nataliia, Heyder, Christoph, Dührkop, Claudia, Nirschl, Hermann, Ekdahl, Kristina Nilsson, Nilsson, Bo, Mastrobattista, Enrico, Kok, Robbert Jan, Afd Pharmaceutics, Pharmaceutics, Afd Pharmaceutics, and Pharmaceutics

Subjects
Pharmacology, Chemistry, Cancer therapy, Pharmaceutical Science, triggered release, inhibition of complement activation, Complementary and alternative medicine, tumour targeting, Drug Discovery, Liposomes, Molecular Medicine, mistletoe, Flow process, encapsulation of biopharmaceuticals
Published
2019

28. Colloidal formulation of mistletoe extracts in a pharmaceutical flow process for targeted cancer therapy

Author

Afd Pharmaceutics, Pharmaceutics, Leneweit, Gero, Miranda, Bárbara S., de Matos, Maria B.C., Beztsinna, Nataliia, Heyder, Christoph, Dührkop, Claudia, Nirschl, Hermann, Ekdahl, Kristina Nilsson, Nilsson, Bo, Mastrobattista, Enrico, Kok, Robbert Jan, Afd Pharmaceutics, Pharmaceutics, Leneweit, Gero, Miranda, Bárbara S., de Matos, Maria B.C., Beztsinna, Nataliia, Heyder, Christoph, Dührkop, Claudia, Nirschl, Hermann, Ekdahl, Kristina Nilsson, Nilsson, Bo, Mastrobattista, Enrico, and Kok, Robbert Jan

Published
2019

30. Liposomes with asymmetric bilayers produced from inverse emulsions for nucleic acid delivery

Author

CDL Cluster Onderzoek en Onderwijs, Cancer, Circulatory Health, de Matos, Maria B. C., Miranda, Barbara S., Nuari, Yudha Rizky, Storm, Gert, Leneweit, Gero, Schiffelers, Raymond M., Kok, Robbert J., CDL Cluster Onderzoek en Onderwijs, Cancer, Circulatory Health, de Matos, Maria B. C., Miranda, Barbara S., Nuari, Yudha Rizky, Storm, Gert, Leneweit, Gero, Schiffelers, Raymond M., and Kok, Robbert J.

Published
2019

31. Instability Mechanisms of Water-in-Oil Nanoemulsions with Phospholipids: Temporal and Morphological Structures

Author

Sommerling, Jan-Hendrik, Carreira de Matos, Maria, Hildebrandt, Ellen, Dessy, Alberto, Kok, Robbert Jan, Nirschl, Hermann, Leneweit, Gero, Afd Pharmaceutics, Pharmaceutics, Afd Pharmaceutics, and Pharmaceutics

Subjects
Coalescence (physics), Ostwald ripening, Liposome, Molecular diffusion, Chemistry, Sonication, 02 engineering and technology, Surfaces and Interfaces, 010402 general chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Micelle, 0104 chemical sciences, symbols.namesake, Chemical engineering, Emulsion, Electrochemistry, symbols, General Materials Science, Solubility, 0210 nano-technology, Spectroscopy
Abstract

Many food preparations, pharmaceuticals, and cosmetics use water-in-oil (W/O) emulsions stabilized by phospholipids. Moreover, recent technological developments try to produce liposomes or lipid coated capsules from W/O emulsions, but are faced with colloidal instabilities. To explore these instability mechanisms, emulsification by sonication was applied in three cycles, and the sample stability was studied for 3 h after each cycle. Clearly identifiable temporal structures of instability provide evidence about the emulsion morphology: an initial regime of about 10 min is shown to be governed by coalescence after which Ostwald ripening dominates. Transport via molecular diffusion in Ostwald ripening is commonly based on the mutual solubility of the two phases and is therefore prohibited in emulsions composed of immiscible phases. However, in the case of water in oil emulsified by phospholipids, these form water-loaded reverse micelles in oil, which enable Ostwald ripening despite the low solubility of water in oil, as is shown for squalene. As is proved for the phospholipid dipalmitoylphosphatidylcholine (DPPC), concentrations below the critical aggregation concentration (CAC) form monolayers at the interfaces and smaller droplet sizes. In contrast, phospholipid concentrations above the CAC create complex multilayers at the interface with larger droplet sizes. The key factors for stable W/O emulsions in classical or innovative applications are first, the minimization of the phospholipids' capacity to form reversed micelles, and second, the adaption of the initial phospholipid concentration to the water content to enable an optimized coverage of phospholipids at the interfaces for the intended drop size.

Published
2018

35. Water‐in‐Fluorocarbon Nanoemulsions Stabilized by Phospholipids and Characterized for Pharmaceutical Applications.

Author

Ullmann, Kirsten, Meier, Manuel, Benner, Carolyn, Leneweit, Gero, and Nirschl, Hermann

Subjects
LIGHT beating spectroscopy, SMALL-angle X-ray scattering, LIPOSOMES, MANUFACTURING processes, REFRACTIVE index
Abstract

Fluorocarbons are one of the most promising hydrophobic phases for future pharmaceutical production processes and various biomedical applications. Yet, because of their specific characteristics such as high density and refractive index similar to water, analysis of water‐in‐fluorocarbon (w/fc) nanoemulsions remains a challenge. The present work examines w/fc nanoemulsions stabilized with phospholipids as natural emulsifiers and tackles the measuring problems of photon correlation spectroscopy (PCS) when used for investigation of fluorocarbon nanoemulsions. These emulsions are suitable to form liposomes via centrifugation and thus, are required to meet certain criteria such as stability and size. The results imply a stability of up to 4 weeks with an average size of 180 nm. The intensity mean diameter gained from PCS measurements shows large scattering directly after sonication which is due to gas bubbles from sonication. The number mean is not influenced by gas bubbles and gives a more accurate depiction of the produced nanoemulsions. These findings are supported by small‐angle X‐ray scattering data, which are additionally applied for liposome analysis measuring a size of approximately 60 nm. [ABSTRACT FROM AUTHOR]

Published
2021
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37. Thermosensitive liposomes for triggered release of cytotoxic proteins

Author

Afd Pharmaceutics, Pharmaceutics, de Matos, Maria B.C., Beztsinna, Nataliia, Heyder, Christoph, Fens, Marcel H.A.M., Mastrobattista, Enrico, Schiffelers, Raymond M., Leneweit, Gero, Kok, Robbert J., Afd Pharmaceutics, Pharmaceutics, de Matos, Maria B.C., Beztsinna, Nataliia, Heyder, Christoph, Fens, Marcel H.A.M., Mastrobattista, Enrico, Schiffelers, Raymond M., Leneweit, Gero, and Kok, Robbert J.

Published
2018

38. Thermosensitive liposomes for triggered release of cytotoxic proteins

Author

CDL Cluster Onderzoek en Onderwijs, Circulatory Health, de Matos, Maria B.C., Beztsinna, Nataliia, Heyder, Christoph, Fens, Marcel H.A.M., Mastrobattista, Enrico, Schiffelers, Raymond M., Leneweit, Gero, Kok, Robbert J., CDL Cluster Onderzoek en Onderwijs, Circulatory Health, de Matos, Maria B.C., Beztsinna, Nataliia, Heyder, Christoph, Fens, Marcel H.A.M., Mastrobattista, Enrico, Schiffelers, Raymond M., Leneweit, Gero, and Kok, Robbert J.

Published
2018

42. Reinhard Koehler. 12. März 1935 bis 14. März 2012

Author

von Laue, Hans Broder and Leneweit, Gero

Abstract

Elemente der Naturwissenschaft 97, p. 70-78., Veranlagungen und Begabungen Reinhard Koehlers Kinder- und Jugendzeit ist vom Zeitschicksal geprägt: Er wird als drittes von fünf Kindern eines Regierungsbeamten 1935 in Königsberg/Preußen in eine noch bürgerliche Welt hinein geboren. Die Schulzeit beginnt während des Krieges und wird durch die Flucht unterbrochen. Die Kinder leben monatelang voller Unsicherheit und Angst: Einmarsch der russischen Armee, entbehrungsreicher Treck, zwei Tage «zwischen Himmel und Erde» im Güterzug von Küstrin nach Berlin. Im Internat Schloss Gebesee bei Erfurt findet er von 1945-1948 geordnete Erziehung und Verpflegung bei Mitarbeit in der Landwirtschaft und Gärtnerei, sowie anspruchsvolle Anleitung in Musik und Literatur; 1948-1950 wird die Schulzeit im Internat St. Peter Ording und in Kiel fortgesetzt. Der Vater findet zunächst in Kiel wieder Arbeit im fremden Beruf. Hier begegnet Reinhard Koehler den beiden Pfarrern der Christengemeinschaft F. Benesch und K. Raschen und beteiligt sich am Jugendkreis. [...]

Published
2012
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43. Liposomal formulations of mistletoe produced by centrifugal technologies suitable for cancer therapy

Author

Leneweit, Gero, Klapper, Yvonne, de Matos, Maria, Hilde-brandt, Ellen, Sommerling, Jan-Hendrik, Duehrkop, Claudia, Dessy, Alberto, Fedotenko, Illya, Nirschl, Hermann, Kok, Robbert Jan, Ekdahl, Kristina Nilsson, Nilsson, Bo, Heyder, Christoph, Leneweit, Gero, Klapper, Yvonne, de Matos, Maria, Hilde-brandt, Ellen, Sommerling, Jan-Hendrik, Duehrkop, Claudia, Dessy, Alberto, Fedotenko, Illya, Nirschl, Hermann, Kok, Robbert Jan, Ekdahl, Kristina Nilsson, Nilsson, Bo, and Heyder, Christoph

Published
2015
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44. Liposomal formulations of mistletoe produced by centrifugal technologies suitable for cancer therapy

Author

Leneweit, Gero, primary, Klapper, Yvonne, additional, de Matos, Maria, additional, Hilde-brandt, Ellen, additional, Sommerling, Jan-Hendrik, additional, Duehrkop, Claudia, additional, Dessy, Alberto, additional, Fedotenko, Illya, additional, Nirschl, Hermann, additional, Kok, Robbert Jan, additional, Ekdahl, Kristina Nilsson, additional, Nilsson, Bo, additional, and Heyder, Christoph, additional

Published
2015
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50. P-0185 Health Service Research on Patients With Colon Cancer in A Network of Integrative Oncology

Author

Schad, Friedemann, primary, Axtner, Jan, additional, Happe, Antje, additional, Breitkreuz, Thomas, additional, Paxino, Constantin, additional, Gutsch, Johannes, additional, Matthes, Burkhard, additional, Debus, Marion, additional, Spahn, Guenther, additional, Riess, Hartmut, additional, von Laue, Hans-Broder, additional, Leneweit, Gero, additional, Kroez, Matthias, additional, and Matthes, Harald, additional

Published
2012
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