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Hake A, Germann A, de Beer C, Thielen A, Däumer M, Preiser W, von Briesen H, Pfeifer N. Insights to HIV-1 coreceptor usage by estimating HLA adaptation with Bayesian generalized linear mixed models. PLoS Comput Biol 2023; 19:e1010355. [PMID: 38127856 PMCID: PMC10769057 DOI: 10.1371/journal.pcbi.1010355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 01/05/2024] [Accepted: 11/06/2023] [Indexed: 12/23/2023] Open
Abstract
The mechanisms triggering the human immunodeficiency virus type I (HIV-1) to switch the coreceptor usage from CCR5 to CXCR4 during the course of infection are not entirely understood. While low CD4+ T cell counts are associated with CXCR4 usage, a predominance of CXCR4 usage with still high CD4+ T cell counts remains puzzling. Here, we explore the hypothesis that viral adaptation to the human leukocyte antigen (HLA) complex, especially to the HLA class II alleles, contributes to the coreceptor switch. To this end, we sequence the viral gag and env protein with corresponding HLA class I and II alleles of a new cohort of 312 treatment-naive, subtype C, chronically-infected HIV-1 patients from South Africa. To estimate HLA adaptation, we develop a novel computational approach using Bayesian generalized linear mixed models (GLMMs). Our model allows to consider the entire HLA repertoire without restricting the model to pre-learned HLA-polymorphisms. In addition, we correct for phylogenetic relatedness of the viruses within the model itself to account for founder effects. Using our model, we observe that CXCR4-using variants are more adapted than CCR5-using variants (p-value = 1.34e-2). Additionally, adapted CCR5-using variants have a significantly lower predicted false positive rate (FPR) by the geno2pheno[coreceptor] tool compared to the non-adapted CCR5-using variants (p-value = 2.21e-2), where a low FPR is associated with CXCR4 usage. Consequently, estimating HLA adaptation can be an asset in predicting not only coreceptor usage, but also an approaching coreceptor switch in CCR5-using variants. We propose the usage of Bayesian GLMMs for modeling virus-host adaptation in general.
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Affiliation(s)
- Anna Hake
- Research Group Computational Biology, Max Planck Institute for Informatics, Saarbrücken, Germany
- Saarbrücken Graduate School of Computer Science, Saarland University, Saarbrücken, Germany
| | - Anja Germann
- Main Department Medical Biotechnology, Fraunhofer Institute for Biomedical Engineering, Sulzbach, Germany
| | - Corena de Beer
- Division of Medical Virology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
- National Health Laboratory Service, Tygerberg Business Unit, Cape Town, South Africa
| | | | - Martin Däumer
- Institute of Immunology and Genetics, Kaiserslautern, Germany
| | - Wolfgang Preiser
- Division of Medical Virology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
- National Health Laboratory Service, Tygerberg Business Unit, Cape Town, South Africa
| | - Hagen von Briesen
- Main Department Medical Biotechnology, Fraunhofer Institute for Biomedical Engineering, Sulzbach, Germany
| | - Nico Pfeifer
- Research Group Computational Biology, Max Planck Institute for Informatics, Saarbrücken, Germany
- German Center for Infection Research, Partner Site Tübingen, Tübingen, Germany
- Methods in Medical Informatics, Department of Computer Science, University of Tübingen, Tübingen, Germany
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Al-Nawaiseh S, Krötz C, Rickmann A, Strack C, Germann A, von Briesen H, Szurman P, Schulz A, Stanzel BV. A rabbit model for outer retinal atrophy caused by surgical RPE removal. Graefes Arch Clin Exp Ophthalmol 2023; 261:2265-2280. [PMID: 36976356 PMCID: PMC10368565 DOI: 10.1007/s00417-023-06014-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 01/12/2023] [Accepted: 02/10/2023] [Indexed: 03/29/2023] Open
Abstract
PURPOSE We aimed to establish a rabbit model with retinal atrophy induced by an iatrogenic retinal pigment epithelium (RPE) removal, for future testing of the efficacy and safety of cell therapy strategies. METHODS A localized detachment of the retina from the RPE/choroid layer was created in 18 pigmented rabbits. The RPE was removed by scraping with a custom-made extendable loop instrument. The resulting RPE wound was observed over a time course of 12 weeks with optical coherence tomography and angiography. After 4 days (group 1) and 12 weeks (group 2), histology was done and staining with hematoxylin and eosin, as well as immunofluorescence performed to further investigate the effects of debridement on the RPE and the overlying retina. RESULTS Already after 4 days, we observed a closure of the RPE wound by proliferating RPE and microglia/macrophage cells forming a multilayered clump. This pattern continued over the observation time course of 12 weeks, whereby the inner and outer nuclear layer of the retina became atrophic. No neovascularization was observed in the angiograms or histology. The observed changes were limited to the site of the former RPE wound. CONCLUSIONS Localized surgical RPE removal induced an adjacent progressive retinal atrophy. Altering the natural course of this model may serve as a basis to test RPE cell therapeutics.
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Affiliation(s)
- Sami Al-Nawaiseh
- Eye Clinic Sulzbach, Knappschaft Hospital Saar, Sulzbach/Saar, Germany
| | - Christina Krötz
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
| | | | - Claudine Strack
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Anja Germann
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
| | - Peter Szurman
- Eye Clinic Sulzbach, Knappschaft Hospital Saar, Sulzbach/Saar, Germany
- Klaus Heimann Eye Research Institute (KHERI), Sulzbach/Saar, Germany
| | - André Schulz
- Eye Clinic Sulzbach, Knappschaft Hospital Saar, Sulzbach/Saar, Germany
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
- Klaus Heimann Eye Research Institute (KHERI), Sulzbach/Saar, Germany
| | - Boris V Stanzel
- Eye Clinic Sulzbach, Knappschaft Hospital Saar, Sulzbach/Saar, Germany.
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany.
- Department of Ophthalmology, University of Bonn, Bonn, Germany.
- Klaus Heimann Eye Research Institute (KHERI), Sulzbach/Saar, Germany.
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3
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Bartel-Steinbach M, Lermen D, Gwinner F, Schäfer M, Göen T, Conrad A, Weber T, von Briesen H, Kolossa-Gehring M. Long-term monitoring of mercury in young German adults: Time trend analyses from the German Environmental Specimen Bank, 1995-2018. Environ Res 2022; 207:112592. [PMID: 34973943 DOI: 10.1016/j.envres.2021.112592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
As highlighted in the Minamata Convention, Mercury (Hg) in its various forms poses a substantial risk to human health and the environment. The health relevance of Hg is also recognized by the European Human Biomonitoring Initiative (HBM4EU), which classifies Hg as a priority substance, since considerable knowledge and data gaps on Hg exposure levels and their changes over time still exist in Europe. The German Environmental Specimen Bank (German ESB) provides valuable policy relevant data and long-term trends of substance exposure on a national level for international comparison and evaluation. In this study we analysed data of the German ESB on Hg exposure of young adults aged 20 to 29 including data on urinary Hg levels from 1995 to 2018 and whole blood Hg levels from 2001 to 2010. Results show a clear decrease in both, about 86% in urine total daily Hg excretion from 1995 (0.76 μg/L) to 2018 (0.11 μg/L) (n = 10,069) and about 57% in blood concentrations of Hg from 2001 (1.76 μg/L) to 2010 (0.77 μg/L) (n = 4085). Over the investigated timeframe only a few values exceeded the toxicologically derived health based guidance value HBM I for blood and urine, with these exceedances decreasing over time in line with the general trend. The factors mostly influencing Hg excretion identified in this study are dental amalgam as well as fish and seafood consumption. Besides other factors (e.g. age and sex), also airborne Hg exposure appears to be a low but evident influencing factor in Germany. Although a considerable decrease in internal Hg exposure is recognized in the last decades, the current low-level exposure may cause adverse health effects especially to vulnerable groups such as pregnant women and children. To further elucidate and evaluate current exposure sources and to reduce human exposure to Hg, continuous environmental and human biomonitoring is needed.
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Affiliation(s)
| | - Dominik Lermen
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - Frederik Gwinner
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - Moritz Schäfer
- Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Thomas Göen
- Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - André Conrad
- German Environment Agency (Umweltbundesamt), Berlin, Germany
| | - Till Weber
- German Environment Agency (Umweltbundesamt), Berlin, Germany
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
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4
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Elberskirch L, Le Harzic R, Scheglmann D, Wieland G, Wiehe A, Mathieu-Gaedke M, Golf HRA, von Briesen H, Wagner S. A HET-CAM based vascularized intestine tumor model as a screening platform for nano-formulated photosensitizers. Eur J Pharm Sci 2021; 168:106046. [PMID: 34670122 DOI: 10.1016/j.ejps.2021.106046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 10/15/2021] [Accepted: 10/15/2021] [Indexed: 11/16/2022]
Abstract
The development of new tumor models for anticancer drug screening is a challenge for preclinical research. Conventional cell-based in vitro models such as 2D monolayer cell cultures or 3D spheroids allow an initial assessment of the efficacy of drugs but they have a limited prediction to the in vivo effectiveness. In contrast, in vivo animal models capture the complexity of systemic distribution, accumulation, and degradation of drugs, but visualization of the individual steps is challenging and extracting quantitative data is usually very difficult. Furthermore, there are a variety of ethical concerns related to animal tests. In accordance with the 3Rs principles of Replacement, Reduction and Refinement, alternative test systems should therefore be developed and applied in preclinical research. The Hen's egg test on chorioallantoic membrane (HET-CAM) model provides the generation of vascularized tumor spheroids and therefore, is an ideal test platform which can be used as an intermediate step between in vitro analysis and preclinical evaluation in vivo. We developed a HET-CAM based intestine tumor model to investigate the accumulation and efficacy of nano-formulated photosensitizers. Irradiation is necessary to activate the phototoxic effect. Due to the good accessibility of the vascularized tumor on the CAM, we have developed a laser irradiation setup to simulate an in vivo endoscopic irradiation. The study presents quantitative as well as qualitative data on the accumulation and efficacy of the nano-formulated photosensitizers in a vascularized intestine tumor model.
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Affiliation(s)
- Linda Elberskirch
- Fraunhofer Institute for Biomedical Engineering, Department Bioprocessing & Bioanalytics, Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach (Germany)
| | - Ronan Le Harzic
- Fraunhofer Institute for Biomedical Engineering, Department Bioprocessing & Bioanalytics, Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach (Germany)
| | | | - Gerhard Wieland
- biolitec research GmbH, Otto-Schott-Strasse 15, 07745 Jena (Germany)
| | - Arno Wiehe
- biolitec research GmbH, Otto-Schott-Strasse 15, 07745 Jena (Germany); Freie Universität Berlin, Institute for Chemistry and Biochemistry, Takustr. 3, 14195 Berlin (Germany)
| | - Maria Mathieu-Gaedke
- biolitec research GmbH, Otto-Schott-Strasse 15, 07745 Jena (Germany); Freie Universität Berlin, Institute for Chemistry and Biochemistry, Takustr. 3, 14195 Berlin (Germany)
| | - Hartwig R A Golf
- biolitec research GmbH, Otto-Schott-Strasse 15, 07745 Jena (Germany); Freie Universität Berlin, Institute for Chemistry and Biochemistry, Takustr. 3, 14195 Berlin (Germany)
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, Department Bioprocessing & Bioanalytics, Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach (Germany)
| | - Sylvia Wagner
- Fraunhofer Institute for Biomedical Engineering, Department Bioprocessing & Bioanalytics, Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach (Germany).
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Schultz A, Knoll T, Urban A, Schuck H, von Briesen H, Germann A, Velten T. Novel Cost-Efficient Graphene-Based Impedance Biosensor for the Analysis of Viral Cytopathogenicity and the Effect of Antiviral Drugs. Front Bioeng Biotechnol 2021; 9:718889. [PMID: 34381768 PMCID: PMC8350578 DOI: 10.3389/fbioe.2021.718889] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 06/28/2021] [Indexed: 11/16/2022] Open
Abstract
Biosensors become increasingly relevant for medical diagnostics, pharmaceutical industry, and environmental technology, for example, to test new drugs easily and reliably or to detect cell growth in changing environmental conditions. Novel materials like graphene are promising candidates to produce biosensors on an industrial scale by means of printing processes. To reach this aim, methods for the reliable and automated production of electrode structures and their coating are required. We present an impedance biosensor in the format of a microtiter plate, fabricated by highly efficient roll-to-roll printing of graphene-based microstructures on large-area polymer foils. Proof-of-principle experiments show the evidence of the suitability of the printed graphene biosensors for impedance-based monitoring of viral cytopathogenicity and its inhibition in the presence of antiviral drugs. The developed system is a promising approach toward cost-efficient impedimetric biosensors for high-throughput screening in vaccine research and antiviral drug development.
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Affiliation(s)
- Anke Schultz
- Department of Bioprocessing and Bioanalytics, Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - Thorsten Knoll
- Department of Bioprocessing and Bioanalytics, Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | | | - Herbert Schuck
- Department of Bioprocessing and Bioanalytics, Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - Hagen von Briesen
- Department of Bioprocessing and Bioanalytics, Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - Anja Germann
- Department of Bioprocessing and Bioanalytics, Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - Thomas Velten
- Department of Bioprocessing and Bioanalytics, Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
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6
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Kohl Y, Hesler M, Drexel R, Kovar L, Dähnhardt-Pfeiffer S, Selzer D, Wagner S, Lehr T, von Briesen H, Meier F. Influence of Physicochemical Characteristics and Stability of Gold and Silver Nanoparticles on Biological Effects and Translocation across an Intestinal Barrier-A Case Study from In Vitro to In Silico. Nanomaterials (Basel) 2021; 11:nano11061358. [PMID: 34063963 PMCID: PMC8224057 DOI: 10.3390/nano11061358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/09/2021] [Accepted: 05/13/2021] [Indexed: 11/27/2022]
Abstract
A better understanding of their interaction with cell-based tissue is a fundamental prerequisite towards the safe production and application of engineered nanomaterials. Quantitative experimental data on the correlation between physicochemical characteristics and the interaction and transport of engineered nanomaterials across biological barriers, in particular, is still scarce, thus hampering the development of effective predictive non-testing strategies. Against this background, the presented study investigated the translocation of gold and silver nanoparticles across the gastrointestinal barrier along with related biological effects using an in vitro 3D-triple co-culture cell model. Standardized in vitro assays and quantitative polymerase chain reaction showed no significant influence of the applied nanoparticles on both cell viability and generation of reactive oxygen species. Transmission electron microscopy indicated an intact cell barrier during the translocation study. Single particle ICP-MS revealed a time-dependent increase of translocated nanoparticles independent of their size, shape, surface charge, and stability in cell culture medium. This quantitative data provided the experimental basis for the successful mathematical description of the nanoparticle transport kinetics using a non-linear mixed effects modeling approach. The results of this study may serve as a basis for the development of predictive tools for improved risk assessment of engineered nanomaterials in the future.
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Affiliation(s)
- Yvonne Kohl
- Fraunhofer Institute for Biomedical Engineering IBMT, 66280 Sulzbach, Germany; (M.H.); (S.W.); (H.v.B.)
- Correspondence: (Y.K.); (F.M.); Tel.: +49-6897-9071-256 (Y.K.); +49-8191-985-6880 (F.M.)
| | - Michelle Hesler
- Fraunhofer Institute for Biomedical Engineering IBMT, 66280 Sulzbach, Germany; (M.H.); (S.W.); (H.v.B.)
| | - Roland Drexel
- Postnova Analytics GmbH, 86899 Landsberg am Lech, Germany;
| | - Lukas Kovar
- Department of Clinical Pharmacy, Saarland University, 66123 Saarbrücken, Germany; (L.K.); (D.S.); (T.L.)
| | | | - Dominik Selzer
- Department of Clinical Pharmacy, Saarland University, 66123 Saarbrücken, Germany; (L.K.); (D.S.); (T.L.)
| | - Sylvia Wagner
- Fraunhofer Institute for Biomedical Engineering IBMT, 66280 Sulzbach, Germany; (M.H.); (S.W.); (H.v.B.)
| | - Thorsten Lehr
- Department of Clinical Pharmacy, Saarland University, 66123 Saarbrücken, Germany; (L.K.); (D.S.); (T.L.)
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering IBMT, 66280 Sulzbach, Germany; (M.H.); (S.W.); (H.v.B.)
| | - Florian Meier
- Postnova Analytics GmbH, 86899 Landsberg am Lech, Germany;
- Correspondence: (Y.K.); (F.M.); Tel.: +49-6897-9071-256 (Y.K.); +49-8191-985-6880 (F.M.)
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7
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Kohl Y, Biehl M, Spring S, Hesler M, Ogourtsov V, Todorovic M, Owen J, Elje E, Kopecka K, Moriones OH, Bastús NG, Simon P, Dubaj T, Rundén-Pran E, Puntes V, William N, von Briesen H, Wagner S, Kapur N, Mariussen E, Nelson A, Gabelova A, Dusinska M, Velten T, Knoll T. Microfluidic In Vitro Platform for (Nano)Safety and (Nano)Drug Efficiency Screening. Small 2021; 17:e2006012. [PMID: 33458959 DOI: 10.1002/smll.202006012] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 12/18/2020] [Indexed: 06/12/2023]
Abstract
Microfluidic technology is a valuable tool for realizing more in vitro models capturing cellular and organ level responses for rapid and animal-free risk assessment of new chemicals and drugs. Microfluidic cell-based devices allow high-throughput screening and flexible automation while lowering costs and reagent consumption due to their miniaturization. There is a growing need for faster and animal-free approaches for drug development and safety assessment of chemicals (Registration, Evaluation, Authorisation and Restriction of Chemical Substances, REACH). The work presented describes a microfluidic platform for in vivo-like in vitro cell cultivation. It is equipped with a wafer-based silicon chip including integrated electrodes and a microcavity. A proof-of-concept using different relevant cell models shows its suitability for label-free assessment of cytotoxic effects. A miniaturized microscope within each module monitors cell morphology and proliferation. Electrodes integrated in the microfluidic channels allow the noninvasive monitoring of barrier integrity followed by a label-free assessment of cytotoxic effects. Each microfluidic cell cultivation module can be operated individually or be interconnected in a flexible way. The interconnection of the different modules aims at simulation of the whole-body exposure and response and can contribute to the replacement of animal testing in risk assessment studies in compliance with the 3Rs to replace, reduce, and refine animal experiments.
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Affiliation(s)
- Yvonne Kohl
- Fraunhofer Institute for Biomedical Engineering IBMT, Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Joseph-von-Fraunhofer-Weg 1, Sulzbach, 66280, Germany
| | - Margit Biehl
- Fraunhofer Institute for Biomedical Engineering IBMT, Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Joseph-von-Fraunhofer-Weg 1, Sulzbach, 66280, Germany
| | - Sarah Spring
- Fraunhofer Institute for Biomedical Engineering IBMT, Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Joseph-von-Fraunhofer-Weg 1, Sulzbach, 66280, Germany
| | - Michelle Hesler
- Fraunhofer Institute for Biomedical Engineering IBMT, Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Joseph-von-Fraunhofer-Weg 1, Sulzbach, 66280, Germany
| | - Vladimir Ogourtsov
- Tyndall National Institute, University College Cork, Dyke Parade, Cork, T12 R5CP, Ireland
| | - Miomir Todorovic
- Tyndall National Institute, University College Cork, Dyke Parade, Cork, T12 R5CP, Ireland
| | - Joshua Owen
- Institute of Thermofluids, School of Mechanical Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - Elisabeth Elje
- NILU-Norwegian Institute for Air Research, Department for Environmental Chemistry, Health Effects Laboratory, Instituttveien 18, Kjeller, 2007, Norway
- Faculty of Medicine, Institute of Basic Medical Sciences, Department of Molecular Medicine, University of Oslo, Sognsvannsveien 9, Oslo, 0372, Norway
| | - Kristina Kopecka
- Department of Nanobiology, Cancer Research Institute, Biomedical Research Center of the Slovak Academy of Sciences, Dubravska cesta 9, Bratislava, 84505, Slovakia
| | - Oscar Hernando Moriones
- Institut Català de Nanociència i Nanotecnologia (ICN2), CSIC and BIST, Campus UAB, Bellaterra 08193, Barcelona, Spain
- Universitat Autònoma de Barcelona (UAB), Campus UAB, Bellaterra, 08193, Barcelona, Spain
| | - Neus G Bastús
- Institut Català de Nanociència i Nanotecnologia (ICN2), CSIC and BIST, Campus UAB, Bellaterra 08193, Barcelona, Spain
| | - Peter Simon
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology SUT, Radlinskeho 9, Bratislava, 812 37, Slovakia
| | - Tibor Dubaj
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology SUT, Radlinskeho 9, Bratislava, 812 37, Slovakia
| | - Elise Rundén-Pran
- NILU-Norwegian Institute for Air Research, Department for Environmental Chemistry, Health Effects Laboratory, Instituttveien 18, Kjeller, 2007, Norway
| | - Victor Puntes
- Institut Català de Nanociència i Nanotecnologia (ICN2), CSIC and BIST, Campus UAB, Bellaterra 08193, Barcelona, Spain
- Vall d'Hebron Institut de Recerca (VHIR), Barcelona, 08193, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, 08193, Spain
| | - Nicola William
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering IBMT, Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Joseph-von-Fraunhofer-Weg 1, Sulzbach, 66280, Germany
| | - Sylvia Wagner
- Fraunhofer Institute for Biomedical Engineering IBMT, Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Joseph-von-Fraunhofer-Weg 1, Sulzbach, 66280, Germany
| | - Nikil Kapur
- Institute of Thermofluids, School of Mechanical Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - Espen Mariussen
- NILU-Norwegian Institute for Air Research, Department for Environmental Chemistry, Health Effects Laboratory, Instituttveien 18, Kjeller, 2007, Norway
| | - Andrew Nelson
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK
| | - Alena Gabelova
- Department of Nanobiology, Cancer Research Institute, Biomedical Research Center of the Slovak Academy of Sciences, Dubravska cesta 9, Bratislava, 84505, Slovakia
| | - Maria Dusinska
- NILU-Norwegian Institute for Air Research, Department for Environmental Chemistry, Health Effects Laboratory, Instituttveien 18, Kjeller, 2007, Norway
| | - Thomas Velten
- Fraunhofer Institute for Biomedical Engineering IBMT, Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Joseph-von-Fraunhofer-Weg 1, Sulzbach, 66280, Germany
| | - Thorsten Knoll
- Fraunhofer Institute for Biomedical Engineering IBMT, Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Joseph-von-Fraunhofer-Weg 1, Sulzbach, 66280, Germany
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Kern F, Krammes L, Danz K, Diener C, Kehl T, Küchler O, Fehlmann T, Kahraman M, Rheinheimer S, Aparicio-Puerta E, Wagner S, Ludwig N, Backes C, Lenhof HP, von Briesen H, Hart M, Keller A, Meese E. Validation of human microRNA target pathways enables evaluation of target prediction tools. Nucleic Acids Res 2021; 49:127-144. [PMID: 33305319 PMCID: PMC7797041 DOI: 10.1093/nar/gkaa1161] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 10/20/2020] [Accepted: 11/13/2020] [Indexed: 12/17/2022] Open
Abstract
MicroRNAs are regulators of gene expression. A wide-spread, yet not validated, assumption is that the targetome of miRNAs is non-randomly distributed across the transcriptome and that targets share functional pathways. We developed a computational and experimental strategy termed high-throughput miRNA interaction reporter assay (HiTmIR) to facilitate the validation of target pathways. First, targets and target pathways are predicted and prioritized by computational means to increase the specificity and positive predictive value. Second, the novel webtool miRTaH facilitates guided designs of reporter assay constructs at scale. Third, automated and standardized reporter assays are performed. We evaluated HiTmIR using miR-34a-5p, for which TNF- and TGFB-signaling, and Parkinson's Disease (PD)-related categories were identified and repeated the pipeline for miR-7-5p. HiTmIR validated 58.9% of the target genes for miR-34a-5p and 46.7% for miR-7-5p. We confirmed the targeting by measuring the endogenous protein levels of targets in a neuronal cell model. The standardized positive and negative targets are collected in the new miRATBase database, representing a resource for training, or benchmarking new target predictors. Applied to 88 target predictors with different confidence scores, TargetScan 7.2 and miRanda outperformed other tools. Our experiments demonstrate the efficiency of HiTmIR and provide evidence for an orchestrated miRNA-gene targeting.
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Affiliation(s)
- Fabian Kern
- Chair for Clinical Bioinformatics, Saarland University, 66123 Saarbrücken, Germany
| | - Lena Krammes
- Institute of Human Genetics, Saarland University, 66421 Homburg, Germany
| | - Karin Danz
- Department of Bioprocessing & Bioanalytics, Fraunhofer Institute for Biomedical Engineering, 66280 Sulzbach, Germany
| | - Caroline Diener
- Institute of Human Genetics, Saarland University, 66421 Homburg, Germany
| | - Tim Kehl
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
| | - Oliver Küchler
- Chair for Clinical Bioinformatics, Saarland University, 66123 Saarbrücken, Germany
| | - Tobias Fehlmann
- Chair for Clinical Bioinformatics, Saarland University, 66123 Saarbrücken, Germany
| | - Mustafa Kahraman
- Chair for Clinical Bioinformatics, Saarland University, 66123 Saarbrücken, Germany
| | | | - Ernesto Aparicio-Puerta
- Chair for Clinical Bioinformatics, Saarland University, 66123 Saarbrücken, Germany.,Department of Genetics, Faculty of Science, University of Granada, 18071 Granada, Spain.,Instituto de Investigación Biosanitaria ibs. Granada, University of Granada, 18071 Granada, Spain
| | - Sylvia Wagner
- Department of Bioprocessing & Bioanalytics, Fraunhofer Institute for Biomedical Engineering, 66280 Sulzbach, Germany
| | - Nicole Ludwig
- Institute of Human Genetics, Saarland University, 66421 Homburg, Germany.,Center of Human and Molecular Biology, Saarland University, 66123 Saarbrücken, Germany
| | - Christina Backes
- Chair for Clinical Bioinformatics, Saarland University, 66123 Saarbrücken, Germany
| | - Hans-Peter Lenhof
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
| | - Hagen von Briesen
- Department of Bioprocessing & Bioanalytics, Fraunhofer Institute for Biomedical Engineering, 66280 Sulzbach, Germany
| | - Martin Hart
- Institute of Human Genetics, Saarland University, 66421 Homburg, Germany
| | - Andreas Keller
- Chair for Clinical Bioinformatics, Saarland University, 66123 Saarbrücken, Germany.,Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany.,Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Eckart Meese
- Institute of Human Genetics, Saarland University, 66421 Homburg, Germany
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9
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Lermen D, Weber T, Göen T, Bartel-Steinbach M, Gwinner F, Mueller SC, Conrad A, Rüther M, von Briesen H, Kolossa-Gehring M. Long-term time trend of lead exposure in young German adults - Evaluation of more than 35 Years of data of the German Environmental Specimen Bank. Int J Hyg Environ Health 2020; 231:113665. [PMID: 33221633 DOI: 10.1016/j.ijheh.2020.113665] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/06/2020] [Accepted: 11/11/2020] [Indexed: 02/06/2023]
Abstract
Lead is a ubiquitous pollutant with well-known effects on human health. As there is no lower toxicological threshold for lead in blood and since data gaps on lead exposure still exist in many European countries, HBM data on lead is of high importance. To address this, the European Human Biomonitoring Initiative HBM4EU classified lead as a priority substance. The German Environmental Specimen Bank (German ESB) has monitored lead exposure since more than 35 years. Using data from the early 1980s to 2019 we reveal and discuss long-term trends in blood lead levels (BLLs) and current internal exposure of young adults in Germany. BLLs in young adults decreased substantially in the investigated period. As results from the ESB sampling site Muenster demonstrate, the geometric mean of BLLs of young adults decreased from 1981 (78,7 μg/L) to 2019 (10.4 μg/L) by about 87%. Trends in human exposure closely correlate with air lead levels (ALLs) provided by the European Monitoring and Evaluation Programme (EMEP). Hence, the decrease of BLLs largely reflects the drop in air lead pollution. Known associations of sex, smoking, alcohol consumption, and housing situation with BLLs are confirmed with data of the German ESB. Although internal lead exposure in Germany decreased substantially, the situation might be different in other European countries. Since 2010, BLLs of young adults in Germany levelled out at approximately 10 μg/L. The toxicity of lead even at low levels is known to cause adverse health effects especially in children following exposure of the child or the mother during pregnancy. To identify current exposure sources and to minimize future lead exposure, continuous monitoring of lead intake and exposure levels is needed.
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Affiliation(s)
- Dominik Lermen
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany.
| | - Till Weber
- German Environment Agency (Umweltbundesamt), Berlin, Germany
| | - Thomas Göen
- Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | | | - Frederik Gwinner
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - Sabine C Mueller
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - André Conrad
- German Environment Agency (Umweltbundesamt), Berlin, Germany
| | - Maria Rüther
- German Environment Agency (Umweltbundesamt), Berlin, Germany
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
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10
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Lermen D, Gwinner F, Bartel-Steinbach M, Mueller SC, Habermann JK, Balwir MB, Smits E, Virgolino A, Fiddicke U, Berglund M, Åkesson A, Bergstrom A, Leander K, Horvat M, Snoj Tratnik J, Posada de la Paz M, Castaño Calvo A, Esteban López M, von Briesen H, Zimmermann H, Kolossa-Gehring M. Towards Harmonized Biobanking for Biomonitoring: A Comparison of Human Biomonitoring-Related and Clinical Biorepositories. Biopreserv Biobank 2020; 18:122-135. [PMID: 32281895 PMCID: PMC7185365 DOI: 10.1089/bio.2019.0092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Human biomonitoring (HBM) depends on high-quality human samples to identify status and trends in exposure and ensure comparability of results. In this context, much effort has been put into the development of standardized processes and quality assurance for sampling and chemical analysis, while effects of sample storage and shipment on sample quality have been less thoroughly addressed. To characterize the currently applied storage and shipment procedures within the consortium of the European Human Biomonitoring Initiative (HBM4EU), which aims at harmonization of HBM in Europe, a requirement analysis based on data from an online survey was conducted. In addition, the online survey was addressed to professionals in clinical biobanking represented by members of the European, Middle Eastern and African Society for Biopreservation and Biobanking (ESBB) to identify the current state-of-the-art in terms of sample storage and shipment. Results of this survey conducted in these two networks were compared to detect processes with potential for optimization and harmonization. In general, many similarities exist in sample storage and shipment procedures applied by ESBB members and HBM4EU partners and many requirements for ensuring sample quality are already met also by HBM4EU partners. Nevertheless, a need for improvement was identified for individual steps in sample storage, shipment, and related data management with potential impact on sample and data quality for HBM purposes. Based on these findings, recommendations for crucial first steps to further strengthen sample quality, and thus foster advancement in HBM on a pan-European level are given.
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Affiliation(s)
- Dominik Lermen
- Fraunhofer Institute for Biomedical Engineering IBMT, Biomonitoring & Biobanks, Sulzbach, Germany
- European, Middle Eastern & African Society for Biopreservation and Biobanking, Brussels, Belgium
- The European Human-Biomonitoring Initiative HBM4EU
| | - Frederik Gwinner
- Fraunhofer Institute for Biomedical Engineering IBMT, Biomonitoring & Biobanks, Sulzbach, Germany
- The European Human-Biomonitoring Initiative HBM4EU
| | - Martina Bartel-Steinbach
- Fraunhofer Institute for Biomedical Engineering IBMT, Biomonitoring & Biobanks, Sulzbach, Germany
- The European Human-Biomonitoring Initiative HBM4EU
| | - Sabine C. Mueller
- Fraunhofer Institute for Biomedical Engineering IBMT, Biomonitoring & Biobanks, Sulzbach, Germany
- The European Human-Biomonitoring Initiative HBM4EU
| | - Jens K. Habermann
- European, Middle Eastern & African Society for Biopreservation and Biobanking, Brussels, Belgium
- University Clinical Center Schleswig-Holstein, University of Luebeck, Translational Surgical Oncology and Biobanking, Luebeck, Germany
| | - Matharoo-Ball Balwir
- European, Middle Eastern & African Society for Biopreservation and Biobanking, Brussels, Belgium
- Nottingham University Hospital, Translational Research and Nottingham Health Science Biobank (NHSB), Nottingham, United Kingdom
| | - Elke Smits
- European, Middle Eastern & African Society for Biopreservation and Biobanking, Brussels, Belgium
- Antwerp University Hospital, University of Antwerp, Division of Medical Director, Edegem, Belgium
| | - Ana Virgolino
- The European Human-Biomonitoring Initiative HBM4EU
- Faculdade de Medicina, Instituto de Saúde Ambiental, Universidade de Lisboa, Lisboa, Portugal
| | - Ulrike Fiddicke
- The European Human-Biomonitoring Initiative HBM4EU
- German Environment Agency (Umweltbundesamt), Berlin, Germany
| | - Marika Berglund
- The European Human-Biomonitoring Initiative HBM4EU
- Institute of Environmental Medicine, Karolinska Institute, Institute of Environmental Medicine (IMM), Stockholm, Sweden
| | - Agneta Åkesson
- The European Human-Biomonitoring Initiative HBM4EU
- Institute of Environmental Medicine, Karolinska Institute, Institute of Environmental Medicine (IMM), Stockholm, Sweden
| | - Anna Bergstrom
- The European Human-Biomonitoring Initiative HBM4EU
- Institute of Environmental Medicine, Karolinska Institute, Institute of Environmental Medicine (IMM), Stockholm, Sweden
| | - Karin Leander
- The European Human-Biomonitoring Initiative HBM4EU
- Institute of Environmental Medicine, Karolinska Institute, Institute of Environmental Medicine (IMM), Stockholm, Sweden
| | - Milena Horvat
- The European Human-Biomonitoring Initiative HBM4EU
- Jožef Stefan Institute, Department of Environmental Sciences, Ljubljana, Slovenia
| | - Janja Snoj Tratnik
- The European Human-Biomonitoring Initiative HBM4EU
- Jožef Stefan Institute, Department of Environmental Sciences, Ljubljana, Slovenia
| | - Manuel Posada de la Paz
- The European Human-Biomonitoring Initiative HBM4EU
- Institute of Rare Diseases Research, CIBERER, EuroBiobanK, Instituto de Salud Carlos III, Madrid, Spain
| | - Argelia Castaño Calvo
- The European Human-Biomonitoring Initiative HBM4EU
- Centro Nacional de Sanidad Ambiental CNSA, Instituto de Salud Carlos III, Majadahonda, Spain
| | - Marta Esteban López
- The European Human-Biomonitoring Initiative HBM4EU
- Centro Nacional de Sanidad Ambiental CNSA, Instituto de Salud Carlos III, Majadahonda, Spain
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering IBMT, Biomonitoring & Biobanks, Sulzbach, Germany
- The European Human-Biomonitoring Initiative HBM4EU
| | - Heiko Zimmermann
- Fraunhofer Institute for Biomedical Engineering IBMT, Biomonitoring & Biobanks, Sulzbach, Germany
- The European Human-Biomonitoring Initiative HBM4EU
| | - Marike Kolossa-Gehring
- The European Human-Biomonitoring Initiative HBM4EU
- German Environment Agency (Umweltbundesamt), Berlin, Germany
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11
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Hesler M, Schwarz DH, Dähnhardt-Pfeiffer S, Wagner S, von Briesen H, Wenz G, Kohl Y. Synthesis and in vitro evaluation of cyclodextrin hyaluronic acid conjugates as a new candidate for intestinal drug carrier for steroid hormones. Eur J Pharm Sci 2019; 143:105181. [PMID: 31852628 DOI: 10.1016/j.ejps.2019.105181] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/28/2019] [Accepted: 12/10/2019] [Indexed: 12/17/2022]
Abstract
Steroid hormones became increasingly interesting as active pharmaceutical ingredients for the treatment of endocrine disorders. However, medical applications of many steroidal drugs are inhibited by their very low aqueous solubilities giving rise to low bioavailabilities. Therefore, the prioritized oral administration of steroidal drugs remains problematic. Cyclodextrins are promising candidates for the development of drug delivery systems for oral route applications, since they solubilize hydrophobic steroids and increase their rate of transport in aqueous environments. In this study, the synthesis and characterization of polymeric β-cyclodextrin derivates is described, which result from the attachment of a hydrophilic β-CD-thioether to hyaluronic acid. Host-guest complexes of the synthesized β-cyclodextrin hyaluronic acid conjugates were formed with two poorly soluble model steroids (β-estradiol, dexamethasone) and compared to monomeric β-cyclodextrin derivates regarding solubilization and complexation efficiency. The β-cyclodextrin-drug (host-guest) complexes were evaluated in vitro for their suitability (cytotoxicity and transport rate) as intestinal drug carriers for steroid hormones. In case of β-estradiol, higher solubilities could be achieved by complexation with both synthesized β-cyclodextrin derivates, leading to significantly higher intestinal transport rates in vitro. However, this success could not be shown for dexamethasone, which namely solubilized better, but could not enhance the transport rate significantly. Thus, this study demonstrates the biocompatibility of the synthesized and characterized β-cyclodextrin derivates and shows their potential as new candidate for intestinal drug carrier for steroid hormones like β-estradiol.
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Affiliation(s)
- Michelle Hesler
- Fraunhofer Institute for Biomedical Engineering, Department Bioprocessing & Bioanalytics, Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach, Germany.
| | - Dennis H Schwarz
- Saarland University, Organic Macromolecular Chemistry, 66123 Saarbrücken, Germany.
| | | | - Sylvia Wagner
- Fraunhofer Institute for Biomedical Engineering, Department Bioprocessing & Bioanalytics, Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach, Germany.
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, Department Bioprocessing & Bioanalytics, Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach, Germany.
| | - Gerhard Wenz
- Saarland University, Organic Macromolecular Chemistry, 66123 Saarbrücken, Germany.
| | - Yvonne Kohl
- Fraunhofer Institute for Biomedical Engineering, Department Bioprocessing & Bioanalytics, Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach, Germany.
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12
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Hesler M, Aengenheister L, Ellinger B, Drexel R, Straskraba S, Jost C, Wagner S, Meier F, von Briesen H, Büchel C, Wick P, Buerki-Thurnherr T, Kohl Y. Multi-endpoint toxicological assessment of polystyrene nano- and microparticles in different biological models in vitro. Toxicol In Vitro 2019; 61:104610. [DOI: 10.1016/j.tiv.2019.104610] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 07/16/2019] [Accepted: 07/24/2019] [Indexed: 12/29/2022]
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13
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Abstract
Serum supplementation is crucial in in vitro cell culture to provide all the essential nutrients needed for cellular processes. Fetal bovine serum (FBS) is considered the 'gold standard', but its production raises serious ethical concerns. Human-derived alternatives to FBS exist in the form of human platelet lysates (hPLs) or human AB serum (ABS). However, these serum products are usually pooled from several donors, in order to have a standardised product without patient-specific deviations. Nevertheless, the use of patient-specific serum in cell culture might be the key to successful transplantation of the cultured cells in medical applications, particularly as it avoids the transmission of infectious components or xenogenic proteins. In addition, the production of non-pooled hPL from single donors is likely to be a cost-effective and time-saving method. The current study used hPL units isolated from single donors and tested their performance as medium supplements for cell culture in comparison with FBS or ABS. This proof-of-concept study aimed to assess the potential of non-pooled hPL for personalised serum supplementation, and thus optimise in vitro models by making them more relevant to human physiology. We showed that A549, HepG2 and Caco-2 human cell lines were generally able to adapt to the new culture conditions and maintain viability, morphology and certain cell-specific characteristics. These results indicate that non-pooled, single patient-derived hPL could be a suitable alternative for in vitro serum supplementation.
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Affiliation(s)
- Michelle Hesler
- Department of Bioprocessing & Bioanalytics, Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
| | - Yvonne Kohl
- Department of Bioprocessing & Bioanalytics, Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
| | - Sylvia Wagner
- Department of Bioprocessing & Bioanalytics, Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
| | - Hagen von Briesen
- Department of Bioprocessing & Bioanalytics, Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
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14
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Schulz A, Wahl S, Rickmann A, Ludwig J, Stanzel BV, von Briesen H, Szurman P. Age-Related Loss of Human Vitreal Viscoelasticity. Transl Vis Sci Technol 2019; 8:56. [PMID: 31293811 PMCID: PMC6602139 DOI: 10.1167/tvst.8.3.56] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 05/06/2019] [Indexed: 02/02/2023] Open
Abstract
Purpose To determine the viscoelasticity of human vitreous bodies and its changes with age in order to benefit the understanding and therapy of vitreoretinal diseases. Methods In a postmortem study, 190 human vitreous bodies were extracted from 33- to 92-year-old donors, analyzed with regard to their viscoelastic properties via dynamic mechanical analyses, and compared with bovine and porcine vitreous. Postmortem intervals and donor-related parameters were examined as potential parameters influencing vitreous viscoelasticity. Dynamic moduli of different hyaluronic acid (HA) solutions as well as human vitreous treated with HA injections were determined by frequency sweep tests. Results With age the viscoelasticity of human vitreous bodies decreased significantly and independently of postmortem intervals, diabetes, and the donor's sex. The storage modulus G′ and loss modulus G″ correlated strongly with the donor's age with r = −0.789 and r = −0.764, respectively. Bovine and porcine vitreous bodies exhibited dynamic moduli comparable only to the viscoelastic properties of aged human vitreous and are thus limited models for the simulation of the human vitreous. The viscoelasticity of aged human vitreous bodies was found to be increased after intravitreal injections of highly concentrated HA. Conclusions The present postmortem study is the first to show a significant age-related reduction in the viscoelasticity of entire human vitreous bodies. Highly concentrated HA injections may serve as a possible therapeutic approach for restoring the viscoelasticity of aged vitreous bodies. Translational Relevance These findings improve the understanding and therapy of the vitreous liquefaction with age and the associated vitreoretinal diseases.
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Affiliation(s)
- André Schulz
- Fraunhofer Institute for Biomedical Engineering, Sulzbach, Germany
| | - Silke Wahl
- Knappschaft Eye Clinic Sulzbach, Sulzbach, Germany
| | | | | | - Boris V Stanzel
- Fraunhofer Institute for Biomedical Engineering, Sulzbach, Germany.,Knappschaft Eye Clinic Sulzbach, Sulzbach, Germany
| | | | - Peter Szurman
- Knappschaft Eye Clinic Sulzbach, Sulzbach, Germany.,Centre for Ophthalmology, University Eye Hospital Tuebingen, Tuebingen, Germany
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15
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Lermen D, Bartel-Steinbach M, Gwinner F, Conrad A, Weber T, von Briesen H, Kolossa-Gehring M. Trends in characteristics of 24-h urine samples and their relevance for human biomonitoring studies – 20 years of experience in the German Environmental Specimen Bank. Int J Hyg Environ Health 2019; 222:831-839. [DOI: 10.1016/j.ijheh.2019.04.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 04/17/2019] [Accepted: 04/18/2019] [Indexed: 01/01/2023]
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16
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Schulz A, Gepp MM, Stracke F, von Briesen H, Neubauer JC, Zimmermann H. Tyramine-conjugated alginate hydrogels as a platform for bioactive scaffolds. J Biomed Mater Res A 2018; 107:114-121. [PMID: 30256518 PMCID: PMC6585978 DOI: 10.1002/jbm.a.36538] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 08/14/2018] [Accepted: 08/29/2018] [Indexed: 02/04/2023]
Abstract
Alginate‐based hydrogels represent promising microenvironments for cell culture and tissue engineering, as their mechanical and porous characteristics are adjustable toward in vivo conditions. However, alginate scaffolds are bioinert and thus inhibit cellular interactions. To overcome this disadvantage, bioactive alginate surfaces were produced by conjugating tyramine molecules to high‐molecular‐weight alginates using the carbodiimide chemistry. Structural elucidation using nuclear magnetic resonance spectroscopy and contact angle measurements revealed a surface chemistry and wettability of tyramine‐alginate hydrogels similar to standard cell culture treated polystyrene. In contrast to stiff cell culture plastic, tyramine‐alginate scaffolds were found to be soft (60–80 kPa), meeting the elastic moduli of human tissues such as liver and heart. We further demonstrated an enhanced protein adsorption with increasing tyramine conjugation, stable for several weeks. Cell culture studies with human mesenchymal stem cells and human pluripotent stem cell‐derived cardiomyocytes qualified tyramine‐alginate hydrogels as bioactive platforms enabling cell adhesion and contraction on (structured) 2‐D layer and spherical matrices. Due to the alginate functionalization with tyramines, stable cell–matrix interactions were observed beneficial for an implementation in biology, biotechnology, and medicine toward efficient cell culture and tissue substitutes. © 2018 The Authors. Journal of Biomedical Materials Research Part A published by Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 114–121, 2019.
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Affiliation(s)
- André Schulz
- Fraunhofer Institute for Biomedical Engineering, Sulzbach, 66280, Germany
| | - Michael M Gepp
- Fraunhofer Institute for Biomedical Engineering, Sulzbach, 66280, Germany.,Fraunhofer Project Center for Stem Cell Process Engineering, Wuerzburg, 97082, Germany
| | - Frank Stracke
- Fraunhofer Institute for Biomedical Engineering, Sulzbach, 66280, Germany
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, Sulzbach, 66280, Germany
| | - Julia C Neubauer
- Fraunhofer Institute for Biomedical Engineering, Sulzbach, 66280, Germany.,Fraunhofer Project Center for Stem Cell Process Engineering, Wuerzburg, 97082, Germany
| | - Heiko Zimmermann
- Fraunhofer Institute for Biomedical Engineering, Sulzbach, 66280, Germany.,Chair for Molecular and Cellular Biotechnology, Saarland University, Saarbruecken, 66123, Germany.,Faculty of Marine Science, Universidad Católica del Norte, Coquimbo, Chile
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17
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Schulz A, Katsen-Globa A, Huber EJ, Mueller SC, Kreiner A, Pütz N, Gepp MM, Fischer B, Stracke F, von Briesen H, Neubauer JC, Zimmermann H. Poly(amidoamine)-alginate hydrogels: directing the behavior of mesenchymal stem cells with charged hydrogel surfaces. J Mater Sci Mater Med 2018; 29:105. [PMID: 29961123 PMCID: PMC6028859 DOI: 10.1007/s10856-018-6113-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 06/18/2018] [Indexed: 05/02/2023]
Abstract
The surface charge of a biomaterial represents a promising tool to direct cellular behavior, which is crucial for therapeutic approaches in regenerative medicine. To expand the understanding of how the material surface charge affects protein adsorption and mesenchymal stem cell behavior, differently charged surfaces with zeta potentials spanning from -25 mV to +15 mV were fabricated by the conjugation of poly(amidoamine) to alginate-based hydrogels. We showed that the increase of the biomaterials surface charge resulted in enhanced quantities of biologically available, surface-attached proteins. Since different surface charges were equalized after protein adsorption, mesenchymal stem cells interacted rather with diverse protein compositions instead of different surface features. Besides an enhanced cell attachment to increasingly positively charged surfaces, the cell spreading area and the expression of adhesion-related genes integrin α5 and tensin 1 were found to be increased after adhesion. Moreover, first results indicate a potential impact of the surface charge on mesenchymal stem cell differentiation towards bone and fat cells. The improved understanding of surface charge-related cell behavior has significant impact on the design of biomedical devices and artificial organs.
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Affiliation(s)
- André Schulz
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Alisa Katsen-Globa
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Esther J Huber
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Sabine C Mueller
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Asger Kreiner
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Norbert Pütz
- Faculty of Medicine, Saarland University, Kirrberger Straße 100, 66421, Homburg, Germany
| | - Michael M Gepp
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Benjamin Fischer
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Frank Stracke
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Julia C Neubauer
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Heiko Zimmermann
- Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany.
- Chair for Molecular and Cellular Biotechnology, Saarland University, 66123, Saarbruecken, Germany.
- Faculty of Marine Science, Universidad Católica del Norte, Coquimbo, Chile.
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18
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Schultz A, Germann A, Fuss M, Sarzotti-Kelsoe M, Ozaki DA, Montefiori DC, Zimmermann H, von Briesen H. Validation of an automated system for aliquoting of HIV-1 Env-pseudotyped virus stocks. PLoS One 2018; 13:e0190669. [PMID: 29300769 PMCID: PMC5754138 DOI: 10.1371/journal.pone.0190669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 12/19/2017] [Indexed: 11/17/2022] Open
Abstract
The standardized assessments of HIV-specific immune responses are of main interest in the preclinical and clinical stage of HIV-1 vaccine development. In this regard, HIV-1 Env-pseudotyped viruses play a central role for the evaluation of neutralizing antibody profiles and are produced according to Good Clinical Laboratory Practice- (GCLP-) compliant manual and automated procedures. To further improve and complete the automated production cycle an automated system for aliquoting HIV-1 pseudovirus stocks has been implemented. The automation platform consists of a modified Tecan-based system including a robot platform for handling racks containing 48 cryovials, a Decapper, a tubing pump and a safety device consisting of ultrasound sensors for online liquid level detection of each individual cryovial. With the aim to aliquot the HIV-1 pseudoviruses in an automated manner under GCLP-compliant conditions a validation plan was developed where the acceptance criteria—accuracy, precision as well as the specificity and robustness—were defined and summarized. By passing the validation experiments described in this article the automated system for aliquoting has been successfully validated. This allows the standardized and operator independent distribution of small-scale and bulk amounts of HIV-1 pseudovirus stocks with a precise and reproducible outcome to support upcoming clinical vaccine trials.
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Affiliation(s)
- Anke Schultz
- Fraunhofer Institute for Biomedical Engineering IBMT, Joseph-von-Fraunhofer-Weg 1, Sulzbach, Germany
| | - Anja Germann
- Fraunhofer Institute for Biomedical Engineering IBMT, Joseph-von-Fraunhofer-Weg 1, Sulzbach, Germany
| | - Martina Fuss
- Fraunhofer Institute for Biomedical Engineering IBMT, Joseph-von-Fraunhofer-Weg 1, Sulzbach, Germany
| | - Marcella Sarzotti-Kelsoe
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Daniel A Ozaki
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, United States of America
| | - David C Montefiori
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Heiko Zimmermann
- Fraunhofer Institute for Biomedical Engineering IBMT, Joseph-von-Fraunhofer-Weg 1, Sulzbach, Germany.,Molecular and Cellular Biotechnology/Nanotechnology, Saarland University, Saarbrücken, Germany.,Marine Sciences Universidad Católica del Norte, Antafogasta/Coquimbo, Chile
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering IBMT, Joseph-von-Fraunhofer-Weg 1, Sulzbach, Germany
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Koch K, Kalusche S, Torres JL, Stanfield RL, Danquah W, Khazanehdari K, von Briesen H, Geertsma ER, Wilson IA, Wernery U, Koch-Nolte F, Ward AB, Dietrich U. Selection of nanobodies with broad neutralizing potential against primary HIV-1 strains using soluble subtype C gp140 envelope trimers. Sci Rep 2017; 7:8390. [PMID: 28827559 PMCID: PMC5566552 DOI: 10.1038/s41598-017-08273-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 07/14/2017] [Indexed: 12/13/2022] Open
Abstract
Broadly neutralizing antibodies (bnAbs) against HIV-1 protect from infection and reduce viral load upon therapeutic applications. However no vaccine was able so far to induce bnAbs demanding their expensive biotechnological production. For clinical applications, nanobodies (VHH) derived from heavy chain only antibodies from Camelidae, may be better suited due to their small size, high solubility/stability and extensive homology to human VH3 genes. Here we selected broadly neutralizing nanobodies by phage display after immunization of dromedaries with different soluble trimeric envelope proteins derived from HIV-1 subtype C. We identified 25 distinct VHH families binding trimeric Env, of which 6 neutralized heterologous primary isolates of various HIV-1 subtypes in a standardized in vitro neutralization assay. The complementary neutralization pattern of two selected VHHs in combination covers 19 out of 21 HIV-1 strains from a standardized panel of epidemiologically relevant HIV-1 subtypes. The CD4 binding site was preferentially targeted by the broadly neutralizing VHHs as determined by competition ELISAs and 3D models of VHH-Env complexes derived from negative stain electron microscopy. The nanobodies identified here are excellent candidates for further preclinical/clinical development for prophylactic and therapeutic applications due to their potency and their complementary neutralization patterns covering the majority of epidemiologically relevant HIV-1 subtypes.
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Affiliation(s)
- Kathrin Koch
- Georg-Speyer-Haus, Paul-Ehrlich-Str, 42-44, 60596, Frankfurt, Germany
| | - Sarah Kalusche
- Georg-Speyer-Haus, Paul-Ehrlich-Str, 42-44, 60596, Frankfurt, Germany
| | - Jonathan L Torres
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, 92037, USA
| | - Robyn L Stanfield
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, 92037, USA
| | - Welbeck Danquah
- Institute of Immunology, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | | | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, 66280, Sulzbach, Germany
| | - Eric R Geertsma
- Institute of Biochemistry, Biocenter, Goethe-University Frankfurt, Frankfurt, Germany
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, 92037, USA
| | - Ulrich Wernery
- Central Veterinary Research Laboratory, Dubai, United Arab Emirates
| | - Friedrich Koch-Nolte
- Institute of Immunology, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, 92037, USA
| | - Ursula Dietrich
- Georg-Speyer-Haus, Paul-Ehrlich-Str, 42-44, 60596, Frankfurt, Germany.
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20
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Ruffing U, Alabi A, Kazimoto T, Vubil DC, Akulenko R, Abdulla S, Alonso P, Bischoff M, Germann A, Grobusch MP, Helms V, Hoffmann J, Kern WV, Kremsner PG, Mandomando I, Mellmann A, Peters G, Schaumburg F, Schubert S, Strauß L, Tanner M, Briesen HV, Wende L, Müller LV, Herrmann M. Community-Associated Staphylococcus aureus from Sub-Saharan Africa and Germany: A Cross-Sectional Geographic Correlation Study. Sci Rep 2017; 7:154. [PMID: 28273954 PMCID: PMC5428059 DOI: 10.1038/s41598-017-00214-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 02/14/2017] [Indexed: 01/29/2023] Open
Abstract
Clonal clusters and gene repertoires of Staphylococcus aureus are essential to understand disease and are well characterized in industrialized countries but poorly analysed in developing regions. The objective of this study was to compare the molecular-epidemiologic profiles of S. aureus isolates from Sub-Saharan Africa and Germany. S. aureus isolates from 600 staphylococcal carriers and 600 patients with community-associated staphylococcal disease were characterized by DNA hybridization, clonal complex (CC) attribution, and principal component (PCA)-based gene repertoire analysis. 73% of all CCs identified representing 77% of the isolates contained in these CCs were predominant in either African or German region. Significant differences between African versus German isolates were found for alleles encoding the accessory gene regulator type, enterotoxins, the Panton-Valentine leukocidin, immune evasion gene cluster, and adhesins. PCA in conjunction with silhouette analysis distinguished nine separable PCA clusters, with five clusters primarily comprising of African and two clusters of German isolates. Significant differences between S. aureus lineages in Africa and Germany may be a clue to explain the apparent difference in disease between tropical/(so-called) developing and temperate/industrialized regions. In low-resource countries further clinical-epidemiologic research is warranted not only for neglected tropical diseases but also for major bacterial infections.
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Affiliation(s)
- Ulla Ruffing
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg, Germany
| | - Abraham Alabi
- Centre de Recherches Médicales de Lambaréné (CERMEL), Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Theckla Kazimoto
- Ifakara Health Research and Development Centre (IHRDC), Dar es Salaam, Tanzania
| | - Delfino C Vubil
- Manhiça Health Research Center, Manhiça, Manhiça, Mozambique
| | - Ruslan Akulenko
- Center for Bioinformatics, Saarland University, Saarbrücken, Germany
| | - Salim Abdulla
- Ifakara Health Research and Development Centre (IHRDC), Dar es Salaam, Tanzania
| | - Pedro Alonso
- Manhiça Health Research Center, Manhiça, Manhiça, Mozambique.,Department of Public Health, University of Barcelona, Barcelona, Spain
| | - Markus Bischoff
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg, Germany
| | - Anja Germann
- Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Martin P Grobusch
- Centre de Recherches Médicales de Lambaréné (CERMEL), Albert Schweitzer Hospital, Lambaréné, Gabon.,Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, University of Amsterdam, Amsterdam, The Netherlands
| | - Volkhard Helms
- Center for Bioinformatics, Saarland University, Saarbrücken, Germany
| | - Jonas Hoffmann
- Division of Infectious Diseases and Travel Medicine, University of Freiburg, Freiburg, Germany
| | - Winfried V Kern
- Division of Infectious Diseases and Travel Medicine, University of Freiburg, Freiburg, Germany
| | - Peter G Kremsner
- Centre de Recherches Médicales de Lambaréné (CERMEL), Albert Schweitzer Hospital, Lambaréné, Gabon.,Institute of Tropical Medicine, University of Tübingen, Deutsches Zentrum für Infektionsforschung, Tübingen, Germany
| | | | | | - Georg Peters
- Institute of Medical Microbiology, University Hospital Münster, Münster, Germany
| | - Frieder Schaumburg
- Institute of Medical Microbiology, University Hospital Münster, Münster, Germany
| | - Sabine Schubert
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg, Germany
| | - Lena Strauß
- Institute of Hygiene, University Hospital Münster, Münster, Germany
| | - Marcel Tanner
- Ifakara Health Research and Development Centre (IHRDC), Dar es Salaam, Tanzania.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Laura Wende
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg, Germany
| | - Lutz von Müller
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg, Germany
| | - Mathias Herrmann
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg, Germany.
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21
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Angel S, von Briesen H, Oh YJ, Baller MK, Zimmermann H, Germann A. Toward Optimal Cryopreservation and Storage for Achievement of High Cell Recovery and Maintenance of Cell Viability and T Cell Functionality. Biopreserv Biobank 2016; 14:539-547. [PMID: 27792414 PMCID: PMC5180082 DOI: 10.1089/bio.2016.0046] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Cryopreservation of biological materials such as cells, tissues, and organs is a prevailing topic of high importance. It is employed not only in many research fields but also in the clinical area. Cryopreservation is of great importance for reproductive medicine and clinical studies, as well as for the development of vaccines. Peripheral blood mononuclear cells (PBMCs) are commonly used in vaccine research where comparable and reliable results between different research institutions and laboratories are of high importance. Whereas freezing and thawing processes are well studied, controlled, and standardized, storage conditions are often disregarded. To close this gap, we investigated the influence of suboptimal storage conditions during low-temperature storage on PBMC viability, recovery, and T cell functionality. For this purpose, PBMCs were isolated and exposed with help of a robotic system in a low-temperature environment from 0 up to 350 temperature fluctuation cycles in steps of 50 cycles to simulate storage conditions in large biorepositories with sample storage, removal, and sorting functions. After the simulation, the viability, recovery, and T cell functionality were analyzed to determine the number of temperature rises, which ultimately lead to significant cell damage. All studied parameters decreased with increasing number of temperature cycles. Sometimes after as little as only 50 temperature cycles, a significant effect was observed. These results are very important for all fields in which cell cryopreservation is employed, particularly for clinical and multicenter studies wherein the comparability and reproducibility of results play a crucial role. To obtain reliable results and to maintain the quality of the cells, not only the freezing and thawing processes but also the storage conditions should be controlled and standardized, and any deviations should be documented.
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Affiliation(s)
- Stephanie Angel
- 1 Fraunhofer Institute for Biomedical Engineering , Sulzbach, Germany
| | - Hagen von Briesen
- 1 Fraunhofer Institute for Biomedical Engineering , Sulzbach, Germany
| | - Young-Joo Oh
- 1 Fraunhofer Institute for Biomedical Engineering , Sulzbach, Germany
| | - Marko K Baller
- 2 University of Applied Sciences Kaiserslautern , Amerikastraße, Zweibruecken, Germany
| | - Heiko Zimmermann
- 1 Fraunhofer Institute for Biomedical Engineering , Sulzbach, Germany .,3 Department of Molecular and Cellular Biotechnology, Saarland University , Saarbruecken, Germany
| | - Anja Germann
- 1 Fraunhofer Institute for Biomedical Engineering , Sulzbach, Germany
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22
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Niehoff AC, Grünebaum J, Moosmann A, Mulac D, Söbbing J, Niehaus R, Buchholz R, Kröger S, Wiehe A, Wagner S, Sperling M, von Briesen H, Langer K, Karst U. Quantitative bioimaging of platinum group elements in tumor spheroids. Anal Chim Acta 2016; 938:106-13. [DOI: 10.1016/j.aca.2016.07.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 07/19/2016] [Accepted: 07/21/2016] [Indexed: 01/03/2023]
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23
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Hughes SM, Shu Z, Levy CN, Ferre AL, Hartig H, Fang C, Lentz G, Fialkow M, Kirby AC, Adams Waldorf KM, Veazey RS, Germann A, von Briesen H, McElrath MJ, Dezzutti CS, Sinclair E, Baker CAR, Shacklett BL, Gao D, Hladik F. Cryopreservation of Human Mucosal Leukocytes. PLoS One 2016; 11:e0156293. [PMID: 27232996 PMCID: PMC4883784 DOI: 10.1371/journal.pone.0156293] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 05/11/2016] [Indexed: 01/09/2023] Open
Abstract
Background Understanding how leukocytes in the cervicovaginal and colorectal mucosae respond to pathogens, and how medical interventions affect these responses, is important for developing better tools to prevent HIV and other sexually transmitted infections. An effective cryopreservation protocol for these cells following their isolation will make studying them more feasible. Methods and Findings To find an optimal cryopreservation protocol for mucosal mononuclear leukocytes, we compared cryopreservation media and procedures using human vaginal leukocytes and confirmed our results with endocervical and colorectal leukocytes. Specifically, we measured the recovery of viable vaginal T cells and macrophages after cryopreservation with different cryopreservation media and handling procedures. We found several cryopreservation media that led to recoveries above 75%. Limiting the number and volume of washes increased the fraction of cells recovered by 10–15%, possibly due to the small cell numbers in mucosal samples. We confirmed that our cryopreservation protocol also works well for both endocervical and colorectal leukocytes. Cryopreserved leukocytes had slightly increased cytokine responses to antigenic stimulation relative to the same cells tested fresh. Additionally, we tested whether it is better to cryopreserve endocervical cells on the cytobrush or in suspension. Conclusions Leukocytes from cervicovaginal and colorectal tissues can be cryopreserved with good recovery of functional, viable cells using several different cryopreservation media. The number and volume of washes has an experimentally meaningful effect on the percentage of cells recovered. We provide a detailed, step-by-step protocol with best practices for cryopreservation of mucosal leukocytes.
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Affiliation(s)
- Sean M. Hughes
- Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington, United States of America
| | - Zhiquan Shu
- Department of Mechanical Engineering, University of Washington, Seattle, Washington, United States of America
- School of Mechanical and Materials Engineering, Washington State University, Everett, Washington, United States of America
| | - Claire N. Levy
- Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington, United States of America
| | - April L. Ferre
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, Davis, California, United States of America
| | - Heather Hartig
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Cifeng Fang
- Department of Mechanical Engineering, University of Washington, Seattle, Washington, United States of America
| | - Gretchen Lentz
- Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington, United States of America
| | - Michael Fialkow
- Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington, United States of America
| | - Anna C. Kirby
- Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington, United States of America
| | - Kristina M. Adams Waldorf
- Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington, United States of America
| | - Ronald S. Veazey
- Division of Comparative Pathology, Tulane National Primate Research Center, Tulane University School of Medicine, Covington, Louisiana, United States of America
| | - Anja Germann
- Division of Medical Biotechnology, Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach/Saar, Germany
| | - Hagen von Briesen
- Division of Medical Biotechnology, Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach/Saar, Germany
| | - M. Juliana McElrath
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Department of Medicine, University of Washington, Seattle, Washington, United States of America
- Department of Laboratory Medicine, University of Washington, Seattle, Washington, United States of America
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
| | - Charlene S. Dezzutti
- School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Magee-Womens Research Institute, Pittsburgh, Pennsylvania, United States of America
| | - Elizabeth Sinclair
- Division of Experimental Medicine, Department of Medicine, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America
| | - Chris A. R. Baker
- Division of Experimental Medicine, Department of Medicine, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America
- Core Immunology Lab, University of California San Francisco, San Francisco, California, United States of America
| | - Barbara L. Shacklett
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, Davis, California, United States of America
- Department of Medicine, Division of Infectious Diseases, School of Medicine, University of California Davis, Davis, California, United States of America
| | - Dayong Gao
- Department of Mechanical Engineering, University of Washington, Seattle, Washington, United States of America
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
- * E-mail: (DG); (FH)
| | - Florian Hladik
- Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington, United States of America
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Department of Medicine, University of Washington, Seattle, Washington, United States of America
- * E-mail: (DG); (FH)
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Abstract
The development of nonviral gene delivery systems is a great challenge to enable safe gene therapy. In this study, ligand-modified nanoparticles based on human serum albumin (HSA) were developed and optimized for an efficient gene therapy. Different glutaraldehyde cross-linking degrees were investigated to optimize the HSA nanoparticles for gene delivery. The peptide sequence arginine-glycine-aspartate (RGD) and the HIV-1 transactivator of transduction sequence (Tat) are well-known as promising targeting ligands. Plasmid DNA loaded HSA nanoparticles were covalently modified on their surface with these different ligands. The transfection potential of the obtained plasmid DNA loaded RGD- and Tat-modified nanoparticles was investigated in vitro, and optimal incubation conditions for these preparations were studied. It turned out that Tat-modified HSA nanoparticles with the lowest cross-linking degree of 20% showed the highest transfection potential. Taken together, ligand-functionalized HSA nanoparticles represent promising tools for efficient and safe gene therapy.
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Affiliation(s)
- Jennifer Look
- Institute of Pharmaceutical Technology and Biopharmacy, University of Muenster , Corrensstraße 48, Muenster 48149, Germany
| | - Nadine Wilhelm
- Fraunhofer Institute for Biomedical Engineering , Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach, Germany
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering , Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach, Germany
| | - Nadja Noske
- apceth GmbH & Co. KG , Max-Lebsche-Platz 30, 81377 Munich, Germany
| | | | - Klaus Langer
- Institute of Pharmaceutical Technology and Biopharmacy, University of Muenster , Corrensstraße 48, Muenster 48149, Germany
| | - Erwin Gorjup
- Fraunhofer Institute for Biomedical Engineering , Joseph-von-Fraunhofer-Weg 1, 66280 Sulzbach, Germany
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25
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Latorre I, Leidinger P, Backes C, Domínguez J, de Souza-Galvão ML, Maldonado J, Prat C, Ruiz-Manzano J, Sánchez F, Casas I, Keller A, von Briesen H, Knobel H, Meese E, Meyerhans A. A novel whole-blood miRNA signature for a rapid diagnosis of pulmonary tuberculosis. Eur Respir J 2015; 45:1173-6. [PMID: 25657026 DOI: 10.1183/09031936.00221514] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Irene Latorre
- Human Genetics Department, Saarland University, Saarbrücken, Germany Infection Biology Laboratory, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Badalona, Spain These authors contributed equally to this work
| | - Petra Leidinger
- Human Genetics Department, Saarland University, Saarbrücken, Germany These authors contributed equally to this work
| | - Christina Backes
- Clinical Bioinformatics, Saarland University, Saarbrücken, Germany
| | - Jose Domínguez
- CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Badalona, Spain Department of Microbiology, Hospital Universitari Germans Trias i Pujol, Institut d'Investigació Germans Trias i Pujol, Badalona, Spain Universitat Autònoma de Barcelona, Bellaterra, Spain
| | | | | | - Cristina Prat
- CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Badalona, Spain Department of Microbiology, Hospital Universitari Germans Trias i Pujol, Institut d'Investigació Germans Trias i Pujol, Badalona, Spain Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Juan Ruiz-Manzano
- CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Badalona, Spain Universitat Autònoma de Barcelona, Bellaterra, Spain Department of Pneumology, Hospital Universitari Germans Trias i Pujol, Institut d'Investigació Germans Trias i Pujol, Badalona, Spain
| | | | - Irma Casas
- Universitat Autònoma de Barcelona, Bellaterra, Spain Department of Preventive Medicine, Hospital Universitari Germans Trias i Pujol, Institut d'Investigació Germans Trias i Pujol, Badalona, Spain
| | - Andreas Keller
- Clinical Bioinformatics, Saarland University, Saarbrücken, Germany
| | | | - Hernando Knobel
- Universitat Autònoma de Barcelona, Bellaterra, Spain Infectious Diseases Department, Hospital del Mar, Barcelona, Spain
| | - Eckart Meese
- Human Genetics Department, Saarland University, Saarbrücken, Germany
| | - Andreas Meyerhans
- Infection Biology Laboratory, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
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26
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Lermen D, Schmitt D, Bartel-Steinbach M, Schröter-Kermani C, Kolossa-Gehring M, von Briesen H, Zimmermann H. A new approach to standardize multicenter studies: mobile lab technology for the German Environmental Specimen Bank. PLoS One 2014; 9:e105401. [PMID: 25141120 PMCID: PMC4139335 DOI: 10.1371/journal.pone.0105401] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 07/23/2014] [Indexed: 11/24/2022] Open
Abstract
Technical progress has simplified tasks in lab diagnosis and improved quality of test results. Errors occurring during the pre-analytical phase have more negative impact on the quality of test results than errors encountered during the total analytical process. Different infrastructures of sampling sites can highly influence the quality of samples and therewith of analytical results. Annually the German Environmental Specimen Bank (ESB) collects, characterizes, and stores blood, plasma, and urine samples of 120–150 volunteers each on four different sampling sites in Germany. Overarching goal is to investigate the exposure to environmental pollutants of non-occupational exposed young adults combining human biomonitoring with questionnaire data. We investigated the requirements of the study and the possibility to realize a highly standardized sampling procedure on a mobile platform in order to increase the required quality of the pre-analytical phase. The results lead to the development of a mobile epidemiologic laboratory (epiLab) in the project “Labor der Zukunft” (future’s lab technology). This laboratory includes a 14.7 m2 reception area to record medical history and exposure-relevant behavior, a 21.1 m2 examination room to record dental fillings and for blood withdrawal, a 15.5 m2 biological safety level 2 laboratory to process and analyze samples on site including a 2.8 m2 personnel lock and a 3.6 m2 cryofacility to immediately freeze samples. Frozen samples can be transferred to their final destination within the vehicle without breaking the cold chain. To our knowledge, we herewith describe for the first time the implementation of a biological safety laboratory (BSL) 2 lab and an epidemiologic unit on a single mobile platform. Since 2013 we have been collecting up to 15.000 individual human samples annually under highly standardized conditions using the mobile laboratory. Characterized and free of alterations they are kept ready for retrospective analyses in their final archive, the German ESB.
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Affiliation(s)
- Dominik Lermen
- Department of Cell Biology & Applied Virology, Fraunhofer-Institute for Biomedical Engineering, St. Ingbert, Saarland, Germany
| | - Daniel Schmitt
- Department of Laboratory & Information Technology, Fraunhofer-Institute for Biomedical Engineering, St. Ingbert, Saarland, Germany
| | - Martina Bartel-Steinbach
- Department of Cell Biology & Applied Virology, Fraunhofer-Institute for Biomedical Engineering, St. Ingbert, Saarland, Germany
| | | | | | - Hagen von Briesen
- Department of Cell Biology & Applied Virology, Fraunhofer-Institute for Biomedical Engineering, St. Ingbert, Saarland, Germany
| | - Heiko Zimmermann
- Department of Cell Biology & Applied Virology, Fraunhofer-Institute for Biomedical Engineering, St. Ingbert, Saarland, Germany
- Department of Laboratory & Information Technology, Fraunhofer-Institute for Biomedical Engineering, St. Ingbert, Saarland, Germany
- Saarland University, Saarbruecken, Saarland, Germany
- * E-mail:
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Dadparvar M, Wagner S, Wien S, Worek F, von Briesen H, Kreuter J. Freeze-drying of HI-6-loaded recombinant human serum albumin nanoparticles for improved storage stability. Eur J Pharm Biopharm 2014; 88:510-7. [PMID: 24995841 DOI: 10.1016/j.ejpb.2014.06.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 06/11/2014] [Accepted: 06/14/2014] [Indexed: 10/25/2022]
Abstract
Severe intoxications with organophosphates require the immediate administration of atropine in combination with acetyl cholinesterase (AChE) reactivators such as HI-6. Although this therapy regimen enables the treatment of peripheral symptoms, the blood-brain barrier (BBB) restricts the access of the hydrophilic antidotes to the central nervous system which could lead to a fatal respiratory arrest. Therefore, HI-6-loaded albumin nanoparticles were previously developed to enhance the transport across this barrier and were able to reactivate organophosphate-(OP)-inhibited AChE in an in vitro BBB model. Since HI-6 is known to be moisture-sensitive, the feasibility of freeze-drying of the HI-6-loaded nanoparticles was investigated in the present study using different cryo- and lyoprotectants at different concentrations. Trehalose and sucrose (3%, w/v)-containing formulations were superior to mannitol concerning the physicochemical parameters of the nanoparticles whereas trehalose-containing samples were subject of a prolonged storage stability study at temperatures between -20°C and +40°C for predetermined time intervals. Shelf-life computations of the freeze-dried HI-6 nanoparticle formulations revealed a shelf-life time of 18 months when stored at -20°C. The formulations' efficacy was proven in vitro by reactivation of OP-inhibited AChE after transport over a porcine brain capillary endothelial cell layer model.
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Affiliation(s)
- Miriam Dadparvar
- Institute of Pharmaceutical Technology, Johann Wolfgang Goethe University, Frankfurt am Main, Germany
| | - Sylvia Wagner
- Department of Cell Biology & Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Sascha Wien
- Department of Cell Biology & Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Hagen von Briesen
- Department of Cell Biology & Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Jörg Kreuter
- Institute of Pharmaceutical Technology, Johann Wolfgang Goethe University, Frankfurt am Main, Germany.
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Trott M, Weiß S, Antoni S, Koch J, von Briesen H, Hust M, Dietrich U. Functional characterization of two scFv-Fc antibodies from an HIV controller selected on soluble HIV-1 Env complexes: a neutralizing V3- and a trimer-specific gp41 antibody. PLoS One 2014; 9:e97478. [PMID: 24828352 PMCID: PMC4020869 DOI: 10.1371/journal.pone.0097478] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 04/20/2014] [Indexed: 12/30/2022] Open
Abstract
HIV neutralizing antibodies (nAbs) represent an important tool in view of prophylactic and therapeutic applications for HIV-1 infection. Patients chronically infected by HIV-1 represent a valuable source for nAbs. HIV controllers, including long-term non-progressors (LTNP) and elite controllers (EC), represent an interesting subgroup in this regard, as here nAbs can develop over time in a rather healthy immune system and in the absence of any therapeutic selection pressure. In this study, we characterized two particular antibodies that were selected as scFv antibody fragments from a phage immune library generated from an LTNP with HIV neutralizing antibodies in his plasma. The phage library was screened on recombinant soluble gp140 envelope (Env) proteins. Sequencing the selected peptide inserts revealed two major classes of antibody sequences. Binding analysis of the corresponding scFv-Fc derivatives to various trimeric and monomeric Env constructs as well as to peptide arrays showed that one class, represented by monoclonal antibody (mAb) A2, specifically recognizes an epitope localized in the pocket binding domain of the C heptad repeat (CHR) in the ectodomain of gp41, but only in the trimeric context. Thus, this antibody represents an interesting tool for trimer identification. MAb A7, representing the second class, binds to structural elements of the third variable loop V3 and neutralizes tier 1 and tier 2 HIV-1 isolates of different subtypes with matching critical amino acids in the linear epitope sequence. In conclusion, HIV controllers are a valuable source for the selection of functionally interesting antibodies that can be selected on soluble gp140 proteins with properties from the native envelope spike.
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Affiliation(s)
- Maria Trott
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt, Germany
| | - Svenja Weiß
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt, Germany
| | - Sascha Antoni
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt, Germany
| | - Joachim Koch
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt, Germany
| | - Hagen von Briesen
- HIV Specimen Cryorepository (HSC) at Fraunhofer Institute of Biomedical Engineering, St. Ingbert, Germany
| | - Michael Hust
- Technische Universität Braunschweig, Institute of Biochemistry, Biotechnology and Bioinformatics, Braunschweig, Germany
| | - Ursula Dietrich
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt, Germany
- * E-mail:
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Martínez Vera NP, Schmidt R, Langer K, Zlatev I, Wronski R, Auer E, Havas D, Windisch M, von Briesen H, Wagner S, Stab J, Deutsch M, Pietrzik C, Fazekas F, Ropele S. Tracking of magnetite labeled nanoparticles in the rat brain using MRI. PLoS One 2014; 9:e92068. [PMID: 24633006 PMCID: PMC3954869 DOI: 10.1371/journal.pone.0092068] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 02/07/2014] [Indexed: 11/18/2022] Open
Abstract
This study was performed to explore the feasibility of tracing nanoparticles for drug transport in the healthy rat brain with a clinical MRI scanner. Phantom studies were performed to assess the R1 ( = 1/T1) relaxivity of different magnetically labeled nanoparticle (MLNP) formulations that were based on biodegradable human serum albumin and that were labeled with magnetite of different size. In vivo MRI measurements in 26 rats were done at 3T to study the effect and dynamics of MLNP uptake in the rat brain and body. In the brain, MLNPs induced T1 changes were quantitatively assessed by T1 relaxation time mapping in vivo and compared to post-mortem results from fluorescence imaging. Following intravenous injection of MLNPs, a visible MLNP uptake was seen in the liver and spleen while no visual effect was seen in the brain. However a histogram analysis of T1 changes in the brain demonstrated global and diffuse presence of MLNPs. The magnitude of these T1 changes scaled with post-mortem fluorescence intensity. This study demonstrates the feasibility of tracking even small amounts of magnetite labeled NPs with a sensitive histogram technique in the brain of a living rodent.
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Affiliation(s)
| | - Reinhold Schmidt
- Department of Neurology, Medical University of Graz, Graz, Austria
| | - Klaus Langer
- Institute of Pharmaceutical Technology and Biopharmacy, University of Muenster, Muenster, Germany
| | - Iavor Zlatev
- Institute of Pharmaceutical Technology and Biopharmacy, University of Muenster, Muenster, Germany
| | | | - Ewald Auer
- JSW-Live Sciences GmbH, Grambach, Austria
| | | | | | - Hagen von Briesen
- Department of Cell Biology & Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Sylvia Wagner
- Department of Cell Biology & Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Julia Stab
- Department of Cell Biology & Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Motti Deutsch
- Physics Department, Schottenstein Center for the Research and Technology of the Cellome, Bar Ilan University, Ramat Gan, Israel
| | - Claus Pietrzik
- Institute of Pathobiochemistry, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Franz Fazekas
- Department of Neurology, Medical University of Graz, Graz, Austria
| | - Stefan Ropele
- Department of Neurology, Medical University of Graz, Graz, Austria
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Niehoff AC, Moosmann A, Söbbing J, Wiehe A, Mulac D, Wehe CA, Reifschneider O, Blaske F, Wagner S, Sperling M, von Briesen H, Langer K, Karst U. A palladium label to monitor nanoparticle-assisted drug delivery of a photosensitizer into tumor spheroids by elemental bioimaging. Metallomics 2014; 6:77-81. [DOI: 10.1039/c3mt00223c] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Meister S, Zlatev I, Stab J, Docter D, Baches S, Stauber RH, Deutsch M, Schmidt R, Ropele S, Windisch M, Langer K, Wagner S, von Briesen H, Weggen S, Pietrzik CU. Nanoparticulate flurbiprofen reduces amyloid-β42 generation in an in vitro blood-brain barrier model. Alzheimers Res Ther 2013; 5:51. [PMID: 24280275 PMCID: PMC3978673 DOI: 10.1186/alzrt225] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 10/16/2013] [Indexed: 12/16/2022]
Abstract
INTRODUCTION The amyloid-β42 (Aβ42) peptide plays a crucial role in the pathogenesis of Alzheimer's disease (AD), the most common neurodegenerative disorder affecting the elderly. Over the past years, several approaches and compounds developed for the treatment of AD have failed in clinical studies, likely in part due to their low penetration of the blood-brain barrier (BBB). Since nanotechnology-based strategies offer new possibilities for the delivery of drugs to the brain, this technique is studied intensively for the treatment of AD and other neurological disorders. METHODS The Aβ42 lowering drug flurbiprofen was embedded in polylactide (PLA) nanoparticles by emulsification-diffusion technique and their potential as drug carriers in an in vitro BBB model was examined. First, the cytotoxic potential of the PLA-flurbiprofen nanoparticles on endothelial cells and the cellular binding and uptake by endothelial cells was studied. Furthermore, the biological activity of the nanoparticulate flurbiprofen on γ-secretase modulation as well as its in vitro release was examined. Furthermore, the protein corona of the nanoparticles was studied as well as their ability to transport flurbiprofen across an in vitro BBB model. RESULTS PLA-flurbiprofen nanoparticles were endocytosed by endothelial cells and neither affected the vitality nor barrier function of the endothelial cell monolayer. The exposure of the PLA-flurbiprofen nanoparticles to human plasma occurred in a rapid protein corona formation, resulting in their decoration with bioactive proteins, including apolipoprotein E. Furthermore, luminally administered PLA-flurbiprofen nanoparticles in contrast to free flurbiprofen were able to modulate γ-secretase activity by selectively decreasing Aβ42 levels in the abluminal compartment of the BBB model. CONCLUSIONS In this study, we were able to show that flurbiprofen can be transported by PLA nanoparticles across an in vitro BBB model and most importantly, the transported flurbiprofen modulated γ-secretase activity by selectively decreasing Aβ42 levels. These results demonstrate that the modification of drugs via embedding in nanoparticles is a promising tool to facilitate drug delivery to the brain, which enables future development for the treatment of neurodegenerative disorders like AD.
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Affiliation(s)
- Sabrina Meister
- Institute of Pathobiochemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Iavor Zlatev
- Institute of Pharmaceutical Technology and Biopharmacy, University of Muenster, Muenster, Germany
| | - Julia Stab
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Dominic Docter
- Molecular and Cellular Oncology/Mainz Screening Center (MSC), ENT-Department, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Sandra Baches
- Department of Neuropathology, Heinrich Heine University, Duesseldorf, Germany
| | - Roland H Stauber
- Molecular and Cellular Oncology/Mainz Screening Center (MSC), ENT-Department, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Mordechai Deutsch
- The Biophysical Interdisciplinary Schottenstein Center for the Research and Technology of the Cellome, Bar Ilan University, Ramat gan, Israel
| | - Reinhold Schmidt
- Department of Neurology, Medical University of Graz, Graz, Austria
| | - Stefan Ropele
- Department of Neurology, Medical University of Graz, Graz, Austria
| | | | - Klaus Langer
- Institute of Pharmaceutical Technology and Biopharmacy, University of Muenster, Muenster, Germany
| | - Sylvia Wagner
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Hagen von Briesen
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Sascha Weggen
- Department of Neuropathology, Heinrich Heine University, Duesseldorf, Germany
| | - Claus U Pietrzik
- Institute of Pathobiochemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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Germann A, Oh YJ, Schmidt T, Schön U, Zimmermann H, von Briesen H. Temperature fluctuations during deep temperature cryopreservation reduce PBMC recovery, viability and T-cell function. Cryobiology 2013; 67:193-200. [PMID: 23850825 DOI: 10.1016/j.cryobiol.2013.06.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 06/24/2013] [Accepted: 06/26/2013] [Indexed: 10/26/2022]
Abstract
The ability to analyze cryopreserved peripheral blood mononuclear cell (PBMC) from biobanks for antigen-specific immunity is necessary to evaluate response to immune-based therapies. To ensure comparable assay results, collaborative research in multicenter trials needs reliable and reproducible cryopreservation that maintains cell viability and functionality. A standardized cryopreservation procedure is comprised of not only sample collection, preparation and freezing but also low temperature storage in liquid nitrogen without any temperature fluctuations, to avoid cell damage. Therefore, we have developed a storage approach to minimize suboptimal storage conditions in order to maximize cell viability, recovery and T-cell functionality. We compared the influence of repeated temperature fluctuations on cell health from sample storage, sample sorting and removal in comparison to sample storage without temperature rises. We found that cyclical temperature shifts during low temperature storage reduce cell viability, recovery and immune response against specific-antigens. We showed that samples handled under a protective hood system, to avoid or minimize such repeated temperature rises, have comparable cell viability and cell recovery rates to samples stored without any temperature fluctuations. Also T-cell functionality could be considerably increased with the use of the protective hood system compared to sample handling without such a protection system. This data suggests that the impact of temperature fluctuation on cell integrity should be carefully considered in future clinical vaccine trials and consideration should be given to optimal sample storage conditions.
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Affiliation(s)
- Anja Germann
- (a)Fraunhofer Institute for Biomedical Engineering, Ensheimerstr. 48, 66386 St. Ingbert, Germany
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Herrmann M, Abdullah S, Alabi A, Alonso P, Friedrich AW, Fuhr G, Germann A, Kern WV, Kremsner PG, Mandomando I, Mellmann AC, Pluschke G, Rieg S, Ruffing U, Schaumburg F, Tanner M, Peters G, von Briesen H, von Eiff C, von Müller L, Grobusch MP. Staphylococcal disease in Africa: another neglected ‘tropical’ disease. Future Microbiol 2013; 8:17-26. [DOI: 10.2217/fmb.12.126] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The term ‘neglected tropical diseases’ predominantly refers to single-entity, mostly parasitic diseases. However, a considerable morbidity and mortality burden is carried by patients infected with Gram-positive cocci and Gram-negative bacilli that are prevalent all over the world, yet have impact in tropical and developing countries, particularly in children, with much higher incidence rates than those reported from developed countries. Staphylococcus aureus is among these pathogens. The African–German StaphNet consortium uses microbiological characterization of African S. aureus isolates, including identification of virulence factors, alongside the gathering of epidemiological and clinical data in an innovative research network between a European country (Germany) and several African partners. By creating an accessible strain repository and by implementing personnel training and capacity building, this network aims to put staphylococcal disease on the international agenda as a truly neglected condition with a major global impact on public health.
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Affiliation(s)
- Mathias Herrmann
- Institute of Medical Microbiology & Hygiene, University of Saarland Medical Center, Homburg, Germany
| | - Salim Abdullah
- Ifakara Health Research & Development Center, Bagamoyo, Tanzania
| | - Abraham Alabi
- Medical Research Unit, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Pedro Alonso
- Barcelona Centre for International Health Research (Hospital Clínic-Universitat de Barcelona), Barcelona, Spain
- Manhiça Health & Research Center, Maputo, Mozambique
| | - Alexander W Friedrich
- Department of Medical Microbiology, University Hospital Groningen, Groningen, The Netherlands
| | - Günther Fuhr
- Fraunhofer Institute for Biomedical Engineering, St Ingbert, Germany
| | - Anja Germann
- Fraunhofer Institute for Biomedical Engineering, St Ingbert, Germany
| | - Winfried V Kern
- Division of Infectious Diseases, Department of Medicine, University of Freiburg, Freiburg, Germany
| | - Peter G Kremsner
- Medical Research Unit, Albert Schweitzer Hospital, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Inacio Mandomando
- Manhiça Health & Research Center, Maputo, Mozambique
- Instituto Nacional de Saúde, Ministério da Saúde, Maputo, Mozambique
| | | | - Gerd Pluschke
- Swiss Tropical & Public Health Institute & University of Basel, Switzerland
| | - Siegbert Rieg
- Division of Infectious Diseases, Department of Medicine, University of Freiburg, Freiburg, Germany
| | - Ulla Ruffing
- Institute of Medical Microbiology & Hygiene, University of Saarland Medical Center, Homburg, Germany
| | - Frieder Schaumburg
- Medical Research Unit, Albert Schweitzer Hospital, Lambaréné, Gabon
- Institute of Medical Microbiology, University of Münster, Münster, Germany
| | - Marcel Tanner
- Swiss Tropical & Public Health Institute & University of Basel, Switzerland
| | - Georg Peters
- Institute of Medical Microbiology, University of Münster, Münster, Germany
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, St Ingbert, Germany
| | - Christof von Eiff
- Institute of Medical Microbiology, University of Münster, Münster, Germany
| | - Lutz von Müller
- Institute of Medical Microbiology & Hygiene, University of Saarland Medical Center, Homburg, Germany
| | - Martin P Grobusch
- Center for Tropical Medicine & Travel Medicine, Department of Infectious Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Schultz A, Koch S, Fuss M, Mazzotta AS, Sarzotti-Kelsoe M, Ozaki DA, Montefiori DC, von Briesen H, Zimmermann H, Meyerhans A. An automated HIV-1 Env-pseudotyped virus production for global HIV vaccine trials. PLoS One 2012; 7:e51715. [PMID: 23300558 PMCID: PMC3531445 DOI: 10.1371/journal.pone.0051715] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 11/05/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Infections with HIV still represent a major human health problem worldwide and a vaccine is the only long-term option to fight efficiently against this virus. Standardized assessments of HIV-specific immune responses in vaccine trials are essential for prioritizing vaccine candidates in preclinical and clinical stages of development. With respect to neutralizing antibodies, assays with HIV-1 Env-pseudotyped viruses are a high priority. To cover the increasing demands of HIV pseudoviruses, a complete cell culture and transfection automation system has been developed. METHODOLOGY/PRINCIPAL FINDINGS The automation system for HIV pseudovirus production comprises a modified Tecan-based Cellerity system. It covers an area of 5×3 meters and includes a robot platform, a cell counting machine, a CO(2) incubator for cell cultivation and a media refrigerator. The processes for cell handling, transfection and pseudovirus production have been implemented according to manual standard operating procedures and are controlled and scheduled autonomously by the system. The system is housed in a biosafety level II cabinet that guarantees protection of personnel, environment and the product. HIV pseudovirus stocks in a scale from 140 ml to 1000 ml have been produced on the automated system. Parallel manual production of HIV pseudoviruses and comparisons (bridging assays) confirmed that the automated produced pseudoviruses were of equivalent quality as those produced manually. In addition, the automated method was fully validated according to Good Clinical Laboratory Practice (GCLP) guidelines, including the validation parameters accuracy, precision, robustness and specificity. CONCLUSIONS An automated HIV pseudovirus production system has been successfully established. It allows the high quality production of HIV pseudoviruses under GCLP conditions. In its present form, the installed module enables the production of 1000 ml of virus-containing cell culture supernatant per week. Thus, this novel automation facilitates standardized large-scale productions of HIV pseudoviruses for ongoing and upcoming HIV vaccine trials.
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Affiliation(s)
- Anke Schultz
- Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Stefanie Koch
- Department of Virology, Saarland University, Homburg, Germany
| | - Martina Fuss
- Department of Virology, Saarland University, Homburg, Germany
| | | | - Marcella Sarzotti-Kelsoe
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Daniel A. Ozaki
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, United States of America
| | - David C. Montefiori
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Heiko Zimmermann
- Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Andreas Meyerhans
- Department of Virology, Saarland University, Homburg, Germany
- ICREA Infection Biology Laboratory, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
- * E-mail:
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Zhou M, Meyer T, Koch S, Koch J, von Briesen H, Benito JM, Soriano V, Haberl A, Bickel M, Dübel S, Hust M, Dietrich U. Identification of a new epitope for HIV-neutralizing antibodies in the gp41 membrane proximal external region by an Env-tailored phage display library. Eur J Immunol 2012. [PMID: 23180650 DOI: 10.1002/eji.201242974] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
HIV controllers are a valuable source for the identification of HIV-neutralizing antibodies, as chronic infection over decades allows extensive affinity maturation of antibodies for improved Ag recognition. We analyzed a small cohort of elite controllers (ECs) for HIV-neutralizing antibodies using a panel of standardized HIV-1 pseudovirions on TZM-bl cells. An HIV-1 Env-tailored phage display library was generated to select epitopes targeted by neutralizing antibodies in the EC26 plasma sample showing the broadest neutralizing activity. Selected Env fragments were mostly allocated to the membrane proximal external region of gp41. After preabsorbing the EC26 plasma with the selected phage EC26-2A4, we achieved 50% depletion of its neutralizing activity. Furthermore, antibodies affinity-purified with the EC26-2A4 epitope from EC26 plasma showed neutralizing activity, proving that the selected phage indeed contains an epitope targeted by neutralizing plasma antibodies. Epitope fine mapping of the purified plasma antibodies on peptide arrays identified a new epitope overlapping, but clearly distinct, from the prominent 2F5 epitope. Of note, the purified antibodies did not show autoreactivity with cardiolipin, whereas low reactivity with phosphatidylserine comparable to mAb 2F5 was observed. Thus, this new epitope represents a promising candidate for further analysis in view of HIV vaccine development.
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Affiliation(s)
- Mingkui Zhou
- Georg-Speyer-Haus, Institute for Biomedical Research, Frankfurt, Germany
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Schulz JC, Germann A, Kemp-Kamke B, Mazzotta A, von Briesen H, Zimmermann H. Towards a xeno-free and fully chemically defined cryopreservation medium for maintaining viability, recovery, and antigen-specific functionality of PBMC during long-term storage. J Immunol Methods 2012; 382:24-31. [PMID: 22580762 DOI: 10.1016/j.jim.2012.05.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 10/14/2011] [Accepted: 05/01/2012] [Indexed: 11/29/2022]
Abstract
Analysis of cryopreserved peripheral mononuclear cells (PBMC) is important for evaluating new vaccines in immune based therapies and in pathogenesis studies. To ensure comparable assay results from different laboratories and points of time, collaborative research in multicenter trials needs reliable and reproducible cryopreservation protocols that maintain cell viability and functionality. Current cryomedia consist largely of fetal bovine serum (FBS), a natural mix of growth factors, cytokines, and undefined compounds. Standardized procedures are not possible, as FBS can affect the antigen-specific T-cell response, the most important parameter in functionality assays. Also, worldwide sample exchange is complicated by the strict import restrictions on FBS, because of transfection risk. After establishing a serum-free cryopreservation protocol that maintains cell viability, recovery and antigen-specific T-cell response of PBMC comparably to FBS-based cryomedia (Germann et al., 2011), the aim of this study was the complete avoidance of animal proteins and products in combination with efficient cryopreservation. As long-term stability of the cryopreservation process is crucial for retrospective evaluation of samples at different points of time, PBMC were analyzed after storage for maximal four weeks and again after approximately six months. The cryopreservation efficiency of the protein-free and fully chemically defined cryomedium was comparable to FBS-medium after storage for few weeks and several months. Directly after thawing, this medium yielded viabilities over 97% and recovery values over 84%. Also, the specific T-cell functionality was preserved. Additionally, short-term and six month cryopreservation gave comparable results. The fully chemically defined medium presented here will increase standardization and reproducibility of analysis in multicenter-studies or in retrospective evaluation.
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Affiliation(s)
- Julia C Schulz
- Fraunhofer Institute for Biomedical Engineering, 66386 St. Ingbert, Germany
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37
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Wagner S, Zensi A, Wien SL, Tschickardt SE, Maier W, Vogel T, Worek F, Pietrzik CU, Kreuter J, von Briesen H. Uptake mechanism of ApoE-modified nanoparticles on brain capillary endothelial cells as a blood-brain barrier model. PLoS One 2012; 7:e32568. [PMID: 22396775 PMCID: PMC3291552 DOI: 10.1371/journal.pone.0032568] [Citation(s) in RCA: 161] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 01/29/2012] [Indexed: 11/19/2022] Open
Abstract
Background The blood-brain barrier (BBB) represents an insurmountable obstacle for most drugs thus obstructing an effective treatment of many brain diseases. One solution for overcoming this barrier is a transport by binding of these drugs to surface-modified nanoparticles. Especially apolipoprotein E (ApoE) appears to play a major role in the nanoparticle-mediated drug transport across the BBB. However, at present the underlying mechanism is incompletely understood. Methodology/Principal Findings In this study, the uptake of the ApoE-modified nanoparticles into the brain capillary endothelial cells was investigated to differentiate between active and passive uptake mechanism by flow cytometry and confocal laser scanning microscopy. Furthermore, different in vitro co-incubation experiments were performed with competing ligands of the respective receptor. Conclusions/Significance This study confirms an active endocytotic uptake mechanism and shows the involvement of low density lipoprotein receptor family members, notably the low density lipoprotein receptor related protein, on the uptake of the ApoE-modified nanoparticles into the brain capillary endothelial cells. This knowledge of the uptake mechanism of ApoE-modified nanoparticles enables future developments to rationally create very specific and effective carriers to overcome the blood-brain barrier.
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Affiliation(s)
- Sylvia Wagner
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Anja Zensi
- Institute of Pharmaceutical Technology, Goethe-University, Frankfurt am Main, Germany
| | - Sascha L. Wien
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
| | - Sabrina E. Tschickardt
- Institute of Pathobiochemistry, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Wladislaw Maier
- Institute of Pathobiochemistry, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Tikva Vogel
- Laboratory of Pathology and Radiation Biology Branch, National Cancer Institute, National Institute of Health, Bethesda, Maryland, United States of America
| | - Franz Worek
- Bundeswehr Institute of Pharmacology und Toxicology, München, Germany
| | - Claus U. Pietrzik
- Institute of Pathobiochemistry, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Jörg Kreuter
- Institute of Pharmaceutical Technology, Goethe-University, Frankfurt am Main, Germany
| | - Hagen von Briesen
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, St. Ingbert, Germany
- * E-mail:
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Germann A, Schulz JC, Kemp-Kamke B, Zimmermann H, von Briesen H. Standardized Serum-Free Cryomedia Maintain Peripheral Blood Mononuclear Cell Viability, Recovery, and Antigen-Specific T-Cell Response Compared to Fetal Calf Serum-Based Medium. Biopreserv Biobank 2011; 9:229-236. [PMID: 21977240 DOI: 10.1089/bio.2010.0033] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 03/26/2011] [Indexed: 10/17/2022] Open
Abstract
The ability to analyze cryopreserved peripheral blood mononuclear cells (PBMCs) from biobanks for antigen-specific T-cell immunity is necessary to evaluate responses to immune-based therapies. Comprehensive studies have demonstrated that the quality of frozen PBMCs is critical and the maintenance of cell viability and functionality by using appropriate cryopreservation techniques is a key to the successful outcome of assays using PBMCs. Different cryomedia additives affect cell viability. The most common additive is fetal calf serum (FCS), although it is widely known that each FCS lot has to be tested before usage to prevent nonspecific stimulation of T-cells. Also, shipping of samples containing FCS is critical because of many import restrictions. Often, dimethyl sulfoxide (DMSO) is added as a cryoprotectant. However, DMSO concentration has to be reduced significantly because of its toxic effect on cells at room temperature. Therefore, we have developed freezing approaches to minimize cytotoxicity of cryoprotectants and maintain T-cell functionality. We compared different additives to the widely used FCS and found bovine serum albumin fraction V to be an appropriate substitute for the potentially immune-modulating FCS. We also found that DMSO concentration can be reduced by the addition of hydroxyethyl starch. Using our serum-free cryomedia, the PBMC recovery was more than 83% and the PBMC viability was more than 98%. Also, the T-cell functionality measured by enzyme-linked immunospot (ELISpot) was optimal after cryopreservation with our new cryomedia. On the basis of our experimental results, we could finally design 2 different, fully working cryomedia that are standardized, serum free, and manufactured under GMP conditions.
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Kohl Y, Oostingh GJ, Sossalla A, Duschl A, von Briesen H, Thielecke H. Biocompatible micro-sized cell culture chamber for the detection of nanoparticle-induced IL8 promoter activity on a small cell population. Nanoscale Res Lett 2011; 6:505. [PMID: 21861875 PMCID: PMC3212020 DOI: 10.1186/1556-276x-6-505] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 08/23/2011] [Indexed: 05/30/2023]
Abstract
In most conventional in vitro toxicological assays, the response of a complete cell population is averaged, and therefore, single-cell responses are not detectable. Such averaging might result in misinterpretations when only individual cells within a population respond to a certain stimulus. Therefore, there is a need for non-invasive in vitro systems to verify the toxicity of nanoscale materials. In the present study, a micro-sized cell culture chamber with a silicon nitride membrane (0.16 mm2) was produced for cell cultivation and the detection of specific cell responses. The biocompatibility of the microcavity chip (MCC) was verified by studying adipogenic and neuronal differentiation. Thereafter, the suitability of the MCC to study the effects of nanoparticles on a small cell population was determined by using a green fluorescence protein-based reporter cell line. Interleukin-8 promoter (pIL8) induction, a marker of an inflammatory response, was used to monitor immune activation. The validation of the MCC-based method was performed using well-characterized gold and silver nanoparticles. The sensitivity of the new method was verified comparing the quantified pIL8 activation via MCC-based and standard techniques. The results proved the biocompatibility and the sensitivity of the microculture chamber, as well as a high optical quality due to the properties of Si3N4. The MCC-based method is suited for threshold- and time-dependent analysis of nanoparticle-induced IL8 promoter activity. This novel system can give dynamic information at the level of adherent single cells of a small cell population and presents a new non-invasive in vitro test method to assess the toxicity of nanomaterials and other compounds.PACS: 85.35.Be, 81.16.Nd, 87.18.Mp.
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Affiliation(s)
- Yvonne Kohl
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, 66386 St. Ingbert, Germany
| | - Gertie J Oostingh
- Department of Molecular Biology, University of Salzburg, 5020 Salzburg, Austria
| | - Adam Sossalla
- Department of Medical Engineering and Neuroprosthetics, Fraunhofer Institute for Biomedical Engineering, 66386 St. Ingbert, Germany
| | - Albert Duschl
- Department of Molecular Biology, University of Salzburg, 5020 Salzburg, Austria
| | - Hagen von Briesen
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, 66386 St. Ingbert, Germany
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40
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Dadparvar M, Wagner S, Wien S, Kufleitner J, Worek F, von Briesen H, Kreuter J. HI 6 human serum albumin nanoparticles--development and transport over an in vitro blood-brain barrier model. Toxicol Lett 2011; 206:60-6. [PMID: 21726608 DOI: 10.1016/j.toxlet.2011.06.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 06/17/2011] [Accepted: 06/18/2011] [Indexed: 11/19/2022]
Abstract
The standard treatment of intoxication with organophosphorus (OP) compounds includes the administration of oximes acting as acetylcholinesterase (AChE) reactivating antidotes. However, the blood-brain barrier (BBB) restricts the rapid transport of these drugs from the blood into the brain in therapeutically relevant concentrations. Since human serum albumin (HSA) nanoparticles enable the delivery of a variety of drugs across the BBB into the brain, HI 6 dimethanesulfonate and HI 6 dichloride monohydrate were bound to these nanoparticles in the present study. The resulting sorption isotherms showed a better fit to Freundlich's empirical adsorption isotherm than to Langmuir's adsorption isotherm. At the pH of 8.3 maximum drug binding capacities of 344.8 μg and 322.6 μg per mg of nanoparticles were calculated for HI 6 dimethanesulfonate and HI 6 dichloride monohydrate, respectively. These calculated values are higher than the adsorption capacity of 93.5 μg/mg for obidoxime onto HSA nanoparticles determined in a previous study. In vitro testing of the nanoparticulate oxime formulations in primary porcine brain capillary endothelial cells (pBCEC) demonstrated an up to two times higher reactivation of OP-inhibited AChE than the free oximes. These findings show that nanoparticles made of HSA may enable a sufficient antidote OP-poisoning therapy with HI 6 derivatives even within the central nervous system (CNS).
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Affiliation(s)
- Miriam Dadparvar
- Institute of Pharmaceutical Technology, Johann Wolfgang Goethe University, Frankfurt am Main, Germany
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41
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Löw K, Knobloch T, Wagner S, Wiehe A, Engel A, Langer K, von Briesen H. Comparison of intracellular accumulation and cytotoxicity of free mTHPC and mTHPC-loaded PLGA nanoparticles in human colon carcinoma cells. Nanotechnology 2011; 22:245102. [PMID: 21508461 DOI: 10.1088/0957-4484/22/24/245102] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The second generation photosensitizer mTHPC was approved by the European Medicines Agency (EMA) for the palliative treatment of advanced head and neck cancer in October 2001. It is known that mTHPC possesses a significant phototoxicity against a variety of human cancer cells in vitro but also exhibits dark toxicity and can cause adverse effects (especially skin photosensitization). Due to its poor water solubility, the administration of hydrophobic photosensitizer still presents several difficulties. To overcome the administration problems, the use of nanoparticles as drug carrier systems is much investigated. Nanoparticles based on poly(lactic-co-glycolic acid) (PLGA) have been extensively studied as delivery systems into tumours due to their biocompatibility and biodegradability. The goal of this study was the comparison of free mTHPC and mTHPC-loaded PLGA nanoparticles concerning cytotoxicity and intracellular accumulation in human colon carcinoma cells (HT29). The nanoparticles delivered the photosensitizer to the colon carcinoma cells and enabled drug release without losing its activity. The cytotoxicity assays showed a time- and concentration-dependent decrease in cell proliferation and viability after illumination. However, first and foremost mTHPC lost its dark toxic effects using the PLGA nanoparticles as a drug carrier system. Therefore, PLGA nanoparticles are a promising drug carrier system for the hydrophobic photosensitizer mTHPC.
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Affiliation(s)
- Karin Löw
- Fraunhofer-Institute for Biomedical Engineering, D-66386 Straße Ingbert, Germany
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Löw K, Wacker M, Wagner S, Langer K, von Briesen H. Targeted human serum albumin nanoparticles for specific uptake in EGFR-Expressing colon carcinoma cells. Nanomedicine 2011; 7:454-63. [PMID: 21215330 DOI: 10.1016/j.nano.2010.12.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Revised: 12/06/2010] [Accepted: 12/17/2010] [Indexed: 12/31/2022]
Abstract
UNLABELLED The specific application and transport of drugs into malignant tissue is a critical point during diagnosis and therapy. Nanoparticles are known as excellent drug carrier systems and offer the possibility of surface modification with targeting ligands, leading to a specific accumulation in the targeted tissue. First, the specificity of such a carrier system has to be proven. In this study, cetuximab-modified nanoparticles based on biodegradable human serum albumin (HSA) are investigated regarding their cellular binding and intracellular accumulation. Different EGFR-expressing colon carcinoma cells were used to test possible cytotoxic potential, specific binding and intracellular accumulation. A specific accumulation targeting the EGFR could be shown. These results emphasize that cetuximab-modified HSA-nanoparticles are a promising carrier system for later drug transport. To our knowledge, this is the first study investigating the specific accumulation of HSA nanoparticles into different EGFR-expressing colon carcinoma cells. FROM THE CLINICAL EDITOR In this study, cetuximab-modified nanoparticles based on human serum albumin (HSA) are investigated regarding their cellular binding and intracellular accumulation. The results suggest that these nanoparticles are a promising carrier system for EGFR overexpressing colon carcinoma cells.
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Affiliation(s)
- Karin Löw
- Department of Cell Biology and Applied Virology, Fraunhofer-Institute for Biomedical Engineering, St. Ingbert, Germany
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Wagner S, Kufleitner J, Zensi A, Dadparvar M, Wien S, Bungert J, Vogel T, Worek F, Kreuter J, von Briesen H. Nanoparticulate transport of oximes over an in vitro blood-brain barrier model. PLoS One 2010; 5:e14213. [PMID: 21151975 PMCID: PMC2997055 DOI: 10.1371/journal.pone.0014213] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 11/09/2010] [Indexed: 11/19/2022] Open
Abstract
Background Due to the use of organophosphates (OP) as pesticides and the availability of OP-type nerve agents, an effective medical treatment for OP poisonings is still a challenging problem. The acute toxicity of an OP poisoning is mainly due to the inhibition of acetylcholinesterase (AChE) in the peripheral and central nervous systems (CNS). This results in an increase in the synaptic concentration of the neurotransmitter acetylcholine, overstimulation of cholinergic receptors and disorder of numerous body functions up to death. The standard treatment of OP poisoning includes a combination of a muscarinic antagonist and an AChE reactivator (oxime). However, these oximes can not cross the blood-brain barrier (BBB) sufficiently. Therefore, new strategies are needed to transport oximes over the BBB. Methodology/Principal Findings In this study, we combined different oximes (obidoxime dichloride and two different HI 6 salts, HI 6 dichloride monohydrate and HI 6 dimethanesulfonate) with human serum albumin nanoparticles and could show an oxime transport over an in vitro BBB model. In general, the nanoparticulate transported oximes achieved a better reactivation of OP-inhibited AChE than free oximes. Conclusions/Significance With these nanoparticles, for the first time, a tool exists that could enable a transport of oximes over the BBB. This is very important for survival after severe OP intoxication. Therefore, these nanoparticulate formulations are promising formulations for the treatment of the peripheral and the CNS after OP poisoning.
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Affiliation(s)
- Sylvia Wagner
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, Sankt Ingbert, Germany
| | - Jürgen Kufleitner
- Institute of Pharmaceutical Technology, Goethe-University, Frankfurt am Main, Germany
| | - Anja Zensi
- Institute of Pharmaceutical Technology, Goethe-University, Frankfurt am Main, Germany
| | - Miriam Dadparvar
- Institute of Pharmaceutical Technology, Goethe-University, Frankfurt am Main, Germany
| | - Sascha Wien
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, Sankt Ingbert, Germany
| | - Judith Bungert
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, Sankt Ingbert, Germany
| | | | - Franz Worek
- Bundeswehr Institute of Pharmacology und Toxicology, München, Germany
| | - Jörg Kreuter
- Institute of Pharmaceutical Technology, Goethe-University, Frankfurt am Main, Germany
| | - Hagen von Briesen
- Department of Cell Biology and Applied Virology, Fraunhofer Institute for Biomedical Engineering, Sankt Ingbert, Germany
- * E-mail:
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Heinzelmann A, Stein S, Köhl U, Dietrich U, von Briesen H. Regulation of HIV-1 infection in cells derived from purified CD34+ cells through manipulation of APOBEC3G expression. Curr HIV Res 2010; 8:554-63. [PMID: 20642434 DOI: 10.2174/157016210793499231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Accepted: 07/20/2010] [Indexed: 11/22/2022]
Abstract
The cytidine deaminase APOBEC3G has been identified as an antiviral host factor that combats HIV-1. The protein was found to be present in HIV-1 target cells such as macrophages and dendritic cells. The antiviral state of these cells has been partially attributed to a G→A hypermutation of the HIV genome caused by APOBEC3G during reverse transcription. However, the viral infectivity factor (Vif) counteracts this antiviral mechanism by inducing the inactivation of APOBEC3G. In this study, we tested the effect of APOBEC3G expression on the HIV-1 infection of cells derived from purified CD34+ cells that have been transduced with lentiviral vectors containing APOBEC3G and/or shRNAs directed against APOBEC3G and then have been differentiated before infection with HIV-1. In cell lines, the infection was strongly inhibited after upregulation of APOBEC3G. The infection could then be rescued after transducing these cells with shRNAs targeting APOBEC3G. In cells derived from purified CD34+ cells a strong inhibition of the HIV-1 infection was observed in both a Vif defective HIV-1 virus and the corresponding wild-type HIV-1 virus with Vif. Our data implies that when APOBEC3G is expressed high enough, it can escape the inhibition from Vif, thereby exerting its antiviral activity.
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Affiliation(s)
- Anna Heinzelmann
- Georg-Speyer-Haus, Institute for Biomedical Research, Frankfurt am Main, Germany
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45
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Gorjup E, Danner S, Rotter N, Habermann J, Brassat U, Brummendorf TH, Wien S, Meyerhans A, Wollenberg B, Kruse C, Briesen HV. Corrigendum to “Glandular tissue from human pancreas and salivary gland yields similar stem cell populations” [Eur. J. Cell Biol. 88 (2009) 409–421]. Eur J Cell Biol 2010. [DOI: 10.1016/j.ejcb.2009.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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46
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Kufleitner J, Wagner S, Worek F, von Briesen H, Kreuter J. Adsorption of obidoxime onto human serum albumin nanoparticles: Drug loading, particle size and drug release. J Microencapsul 2010; 27:506-13. [DOI: 10.3109/02652041003681406] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Lermen D, Gorjup E, Dyce PW, von Briesen H, Müller P. Neuro-muscular differentiation of adult porcine skin derived stem cell-like cells. PLoS One 2010; 5:e8968. [PMID: 20126464 PMCID: PMC2813294 DOI: 10.1371/journal.pone.0008968] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Accepted: 01/13/2010] [Indexed: 12/17/2022] Open
Abstract
Background Due to the genetic relationship to humans, porcine stem cells are a very important model system to investigate cell differentiation, associated cell signaling pathways, and cell fate. Porcine skin derived stem cells have been isolated from mid-gestation porcine fetus recently. To our knowledge, stem cells from the skin of the adult porcine organism have not been isolated until now. Hence, to our knowledge, we here describe the isolation, expansion, characterization and differentiation of multipotent porcine skin derived stem cell-like cells (pSSCs) from the adult porcine organism for the first time. Methodology/Principal Findings pSSCs had a spindle shaped morphology similar to mesenchymal stem cells (MSCs). They could be maintained proliferatively active in vitro for more than 120 days and were able to form colonies from single cells. pSSCs expressed Sox2 and Oct3/4, both transcription factors essential to the pluripotent and self-renewing phenotypes of embryonic stem cells, which recently gained attention due to their function in inducing pluripotent stem cells. Furthermore, the expression of the progenitor marker nestin, the somatic stem cell markers Bcrp1/ABCG2, Bmi1, and Stat3 was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) in undifferentiated pSSCs. Flow cytometry revealed the expression of the MSC related proteins CD9, CD29, CD44 and CD105, but not CD90. After neuronal differentiation cells with a characteristic morphology of neuronal and smooth muscle-like cells were present in the cultures. Subsequent immunochemistry and flow cytometry revealed the down-regulation of nestin and the up-regulation of the neuron specific protein beta-III-tubulin and the astrocyte marker GFAP. Also, alpha-SMA expressing cells increased during differentiation suggesting the neuro-muscular differentiation of these skin derived cells. pSSCs could also be induced to differentiate into adipocyte-like cells when cultured under specific conditions. Conclusions/Significance Adult porcine skin harbors a population of stem cell-like cells (pSSCs) that can be isolated via enzymatic digestion. These pSSCs show characteristic features of MSCs originated in other tissues and express the embryonic stem cell marker Oct3/4, Sox2, and Stat3. Furthermore, pSSCs have the potential to differentiate into cells from two different germ lines, the ectoderm (neurons, astrocytes) and the mesoderm (smooth muscle cells, adipocytes).
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Affiliation(s)
- Dominik Lermen
- Department of Biogeography, Trier University, Trier, Germany.
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48
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Gorjup E, Danner S, Rotter N, Habermann J, Brassat U, Brummendorf TH, Wien S, Meyerhans A, Wollenberg B, Kruse C, von Briesen H. Glandular tissue from human pancreas and salivary gland yields similar stem cell populations. Eur J Cell Biol 2009; 88:409-21. [DOI: 10.1016/j.ejcb.2009.02.187] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Revised: 01/23/2009] [Accepted: 02/25/2009] [Indexed: 01/04/2023] Open
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49
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Zensi A, Begley D, Pontikis C, Legros C, Mihoreanu L, Wagner S, Büchel C, von Briesen H, Kreuter J. Albumin nanoparticles targeted with Apo E enter the CNS by transcytosis and are delivered to neurones. J Control Release 2009; 137:78-86. [PMID: 19285109 DOI: 10.1016/j.jconrel.2009.03.002] [Citation(s) in RCA: 285] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 02/26/2009] [Accepted: 03/01/2009] [Indexed: 02/04/2023]
Abstract
The blood-brain barrier (BBB) represents a considerable obstacle to brain entry of the majority of drugs and thus severely restricts the therapy of many serious CNS diseases including brain tumours, brain HIV, Alzheimer and other neurodegenerative diseases. The use of nanoparticles coated with polysorbate 80 or with attached apolipoprotein E has enabled the delivery of drugs across the BBB. However, the mechanism of this enhanced transport is still not fully understood. In this present study, human serum albumin nanoparticles, with covalently bound apolipoprotein E (Apo E) as a targetor as well as without apolipoprotein E, were manufactured and injected intravenously into SV 129 mice. The animals were sacrificed after 15 and 30 min, and their brains were examined by transmission electron microscopy. Only the nanoparticles with covalently bound apolipoprotein E were detected in brain capillary endothelial cells and neurones, whereas no uptake into the brain was detectable with nanoparticles without apolipoprotein E. We have also demonstrated uptake of the albumin/ApoE nanoparticles into mouse endothelial (b.End3) cells in vitro and their intracellular localisation. These findings indicate that nanoparticles with covalently bound apolipoprotein E are taken up into the cerebral endothelium by an endocytic mechanism followed by transcytosis into brain parenchyma.
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Affiliation(s)
- Anja Zensi
- Goethe-University, Institute of Pharmaceutical Technology, Max-von-Laue-Str. 9 (Biozentrum), D-60438 Frankfurt am Main, Germany
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50
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Brose C, Schmitt D, von Briesen H, Reimann M. Directed differentiation of pancreatic stem cells by soluble and immobilised signalling factors. Ann Anat 2009; 191:83-93. [DOI: 10.1016/j.aanat.2008.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2008] [Revised: 07/18/2008] [Accepted: 09/03/2008] [Indexed: 12/17/2022]
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