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Gilbert DF, Friedrich O, Wiest J. Assaying Proliferation Characteristics of Cells Cultured Under Static Versus Periodic Conditions. Methods Mol Biol 2023; 2644:35-45. [PMID: 37142914 DOI: 10.1007/978-1-0716-3052-5_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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Two-dimensional in vitro culture models are widely being employed for assessing a vast variety of biological questions in different scientific fields. Common in vitro culture models are typically maintained under static conditions, where the surrounding culture medium is replaced every few days-typically every 48 to 72 h-with the aim to remove metabolites and to replenish nutrients. Although this approach is sufficient for supporting cellular survival and proliferation, static culture conditions do mostly not reflect the in vivo situation where cells are continuously being perfused by extracellular fluid, and thus, create a less-physiological environment. In order to evaluate whether the proliferation characteristics of cells in 2D culture maintained under static conditions differ from cells kept in a dynamic environment, in this chapter, we provide a protocol for differential analysis of cellular growth under static versus pulsed-perfused conditions, mimicking continuous replacement of extracellular fluid in the physiological environment. The protocol involves long-term life-cell high-content time-lapse imaging of fluorescent cells at 37 °C and ambient CO2 concentration using multi-parametric biochips applicable for microphysiological analysis of cellular vitality. We provide instructions and useful information for (i) the culturing of cells in biochips, (ii) setup of cell-laden biochips for culturing cells under static and pulsed-perfused conditions, (iii) long-term life-cell high-content time-lapse imaging of fluorescent cells in biochips, and (iv) quantification of cellular proliferation from image series generated from imaging of differentially cultured cells.
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Affiliation(s)
- Daniel F Gilbert
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering (CBI), Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering (CBI), Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
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Carullo G, Mazzotta S, Koch A, Hartmann KM, Friedrich O, Gilbert DF, Vega-Holm M, Schneider-Stock R, Aiello F. New Oleoyl Hybrids of Natural Antioxidants: Synthesis and In Vitro Evaluation as Inducers of Apoptosis in Colorectal Cancer Cells. Antioxidants (Basel) 2020; 9:antiox9111077. [PMID: 33153029 PMCID: PMC7692320 DOI: 10.3390/antiox9111077] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [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: 10/08/2020] [Revised: 10/27/2020] [Accepted: 10/30/2020] [Indexed: 12/13/2022] Open
Abstract
Nowadays, the beneficial role of a healthy lifestyle, particularly emphasizing the quality of foods and cancer management, is accepted worldwide. Polyphenols and oleic acid play a key role in this context, but are still scarcely used as anti-cancer agents due to their bio-accessibility limits. Therefore, we aimed to synthesize a set of new oleoyl-hybrids of quercetin, morin, pinocembrin, and catechin to overcome the low bioavailability of polyphenols, throughout a bio-catalytic approach using pancreatic porcine lipase as a catalyst. The in vitro assays, using a wide panel of human cancer cell lines showed, mainly for two novel regioisomer oleoyl-hybrids of quercetin, a remarkable increase in apoptotic cell populations. We suggested that the DNA damage shown as ɣH2AX signals might be the major cause of apoptotic cell death. Finally, we demonstrated convincing data about two novel polyphenol-based hybrids displaying a highly selective anti-cancer cytotoxicity and being superior compared to their reference/parental compounds.
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Affiliation(s)
- Gabriele Carullo
- Department of Biotechnology, Chemistry and Pharmacy, Department of Excellence 2018-2022, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy;
- Department of Pharmacy, Health and Nutritional Sciences, Department of Excellence 2018-2022, University of Calabria, Edificio Polifunzionale, 87036 Rende (CS), Italy
| | - Sarah Mazzotta
- Department of Pharmacy, Health and Nutritional Sciences, Department of Excellence 2018-2022, University of Calabria, Edificio Polifunzionale, 87036 Rende (CS), Italy
- Department of Pharmaceutical Sciences, University of Milan Via Luigi Mangiagalli 25, 20133 Milano, Italy;
- Department of Organic and Medicinal Chemistry, Faculty of Pharmacy, University of Seville, Profesor García González 2, 41071 Seville, Spain;
| | - Adrian Koch
- Institiute of Pathology, University Hospital, Friedrich-Alexander University Erlangen-Nürnberg Universitätsstr. 22, 91054 Erlangen, Germany;
- Experimental Tumorpathology, University Hospital, Friedrich-Alexander University Erlangen-Nürnberg Universitätsstr. 22, 91054 Erlangen, Germany
| | - Kristin M. Hartmann
- Institute of Medical Biotechnology Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany; (K.M.H.); (O.F.); (D.F.G.)
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 6, 91052 Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany; (K.M.H.); (O.F.); (D.F.G.)
| | - Daniel F. Gilbert
- Institute of Medical Biotechnology Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany; (K.M.H.); (O.F.); (D.F.G.)
| | - Margarita Vega-Holm
- Department of Organic and Medicinal Chemistry, Faculty of Pharmacy, University of Seville, Profesor García González 2, 41071 Seville, Spain;
| | - Regine Schneider-Stock
- Institiute of Pathology, University Hospital, Friedrich-Alexander University Erlangen-Nürnberg Universitätsstr. 22, 91054 Erlangen, Germany;
- Experimental Tumorpathology, University Hospital, Friedrich-Alexander University Erlangen-Nürnberg Universitätsstr. 22, 91054 Erlangen, Germany
- Correspondence: (R.S.-S.); (F.A.)
| | - Francesca Aiello
- Department of Pharmacy, Health and Nutritional Sciences, Department of Excellence 2018-2022, University of Calabria, Edificio Polifunzionale, 87036 Rende (CS), Italy
- Correspondence: (R.S.-S.); (F.A.)
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Ritter P, Bye LJ, Finol-Urdaneta RK, Lesko C, Adams DJ, Friedrich O, Gilbert DF. A method for high-content functional imaging of intracellular calcium responses in gelatin-immobilized non-adherent cells. Exp Cell Res 2020; 395:112210. [PMID: 32750330 DOI: 10.1016/j.yexcr.2020.112210] [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: 05/14/2020] [Revised: 07/15/2020] [Accepted: 07/28/2020] [Indexed: 11/28/2022]
Abstract
Functional imaging of the intracellular calcium concentration [Ca2+]i using fluorescent indicators is a powerful and frequently applied method for assessing various biological questions in vitro, including ion channel function and intracellular signaling in homeostasis and disease. In functional [Ca2+]i imaging experiments, the fluorescence intensity of single cells is typically recorded during application of a chemical stimulus, i.e. by exchange of modified extracellular media, exposure to drugs and/or ligands. The concomitant mechanical perturbation caused by the perfusion of different solution during experimentation severely hinders calcium imaging in non-adherent cells, including peripheral immune cells, as cells in suspension are dislocated by turbulent flow during chemical stimulation. The quantitative analysis, involving time-courses of intracellular fluorescence signal changes, necessitates cells to remain at the same position throughout the experiment. To prevent dislocation of cells during solution exchange, and to enable imaging as well as analysis of Ca2+ responses in immune cells, a gelatin-based method for immobilization of non-adherent cells was developed. Gelatin has been a long-serving material for cell immobilization, e.g. in 3D bio-printing of cells and has thus, also been employed in the context of this study. To demonstrate the applicability of the established method for functional Ca2+ imaging in gelatin-immobilized suspension cells, a proof-of-concept study was conducted using human peripheral blood model cell lines (Jurkat/T-lymphocytes and THP-1/monocytes), Ca2+ indicators (Fluo-4 and Fura-2) and two different fluorescence microscopy rigs. The data presented that the established methodology is applicable for studying Ca2+ signaling by in vitro high-content functional imaging of [Ca2+]i in suspension cells, including but not restricted to human immune cells.
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Affiliation(s)
- Paul Ritter
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Lydia J Bye
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, Australia
| | - Rocio K Finol-Urdaneta
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, Australia
| | - Christian Lesko
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - David J Adams
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, Australia
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Daniel F Gilbert
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
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Fröhlich T, Mai C, Bogautdinov RP, Morozkina SN, Shavva AG, Friedrich O, Gilbert DF, Tsogoeva SB. Synthesis of Tamoxifen-Artemisinin and Estrogen-Artemisinin Hybrids Highly Potent Against Breast and Prostate Cancer. ChemMedChem 2020; 15:1473-1479. [PMID: 32374071 PMCID: PMC7496903 DOI: 10.1002/cmdc.202000174] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 05/01/2020] [Indexed: 01/02/2023]
Abstract
In the search for new and effective treatments of breast and prostate cancer, a series of hybrid compounds based on tamoxifen, estrogens, and artemisinin were successfully synthesized and analyzed for their in vitro activities against human prostate (PC-3) and breast cancer (MCF-7) cell lines. Most of the hybrid compounds exhibit a strong anticancer activity against both cancer cell lines - for example, EC50 (PC-3) down to 1.07 μM, and EC50 (MCF-7) down to 2.08 μM - thus showing higher activities than their parent compounds 4-hydroxytamoxifen (afimoxifene, 7; EC50 =75.1 (PC-3) and 19.3 μM (MCF-7)), dihydroartemisinin (2; EC50 =263.6 (PC-3) and 49.3 μM (MCF-7)), and artesunic acid (3; EC50 =195.1 (PC-3) and 32.0 μM (MCF-7)). The most potent compounds were the estrogen-artemisinin hybrids 27 and 28 (EC50 =1.18 and 1.07 μM, respectively) against prostate cancer, and hybrid 23 (EC50 =2.08 μM) against breast cancer. These findings demonstrate the high potential of hybridization of artemisinin and estrogens to further improve their anticancer activities and to produce synergistic effects between linked pharmacophores.
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Affiliation(s)
- Tony Fröhlich
- Organic Chemistry Chair I and Interdisciplinary Center for Molecular Materials (ICMM)Friedrich-Alexander University of Erlangen-NürnbergNikolaus-Fiebiger-Straße 1091058ErlangenGermany
| | - Christina Mai
- Organic Chemistry Chair I and Interdisciplinary Center for Molecular Materials (ICMM)Friedrich-Alexander University of Erlangen-NürnbergNikolaus-Fiebiger-Straße 1091058ErlangenGermany
| | | | | | | | - Oliver Friedrich
- Institute of Medical BiotechnologyFriedrich-Alexander University of Erlangen-NürnbergPaul-Gordan-Straße 391052ErlangenGermany
| | - Daniel F. Gilbert
- Institute of Medical BiotechnologyFriedrich-Alexander University of Erlangen-NürnbergPaul-Gordan-Straße 391052ErlangenGermany
| | - Svetlana B. Tsogoeva
- Organic Chemistry Chair I and Interdisciplinary Center for Molecular Materials (ICMM)Friedrich-Alexander University of Erlangen-NürnbergNikolaus-Fiebiger-Straße 1091058ErlangenGermany
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Simon N, Sperber C, Voigtländer C, Born J, Gilbert DF, Seyferth S, Lee G, Kappes B, Friedrich O. Improved stability of polyclonal antibodies: A case study with lyophilization-conserved antibodies raised against epitopes from the malaria parasite Plasmodium falciparum. Eur J Pharm Sci 2020; 142:105086. [PMID: 31626961 DOI: 10.1016/j.ejps.2019.105086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 11/29/2022]
Abstract
Antibodies can be produced as polyclonal (pAb) or monoclonal (mAb) liquid formulations with limited shelf-life. For pAbs, unlike mAbs, only little is known about excipients and lyophilization affecting antibody stability upon reconstitution. We used a model pAb directed against Plasmodium falciparum (Pf) pyridoxal 5'-phosphate synthase 2 (Pdx2) to systemically study effects of bulking agents (amino acids, phosphate buffers, salt solutions), sugar(alcohols), surfactants and protein additions (bovine serum albumin, BSA) in liquid pAb formulations (isolated or in combinations) on the activity to detect the antigen in Pf extracts by Western blots. Repeated freeze-thaw cycles (20x) and extended room temperature storage markedly compromised pAb stability, the former being ameliorated by addition of cryoprotectants (glycerol, sucrose). Lyophilization of pure liquid pAb formulation markedly decreased antibody reactivity upon reconstitution which was not preserved by most bulking agents tested (e.g., histidine, arginine, acetate). Among the tested salt solutions (NaCl, Ringer, PBS), phosphate buffered saline had the largest lyoprotective potential, alongside sucrose, but not trehalose or maltitol. Among combinations of excipients, PBS, sucrose, low concentration BSA and Tween potently preserved PfPdx2 stability. Results for PBS were transferable to PfEnolase pAb, indicating that some of the formulations investigated here might be a low-cost solution for more general applicability to pAbs.
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Affiliation(s)
- Nina Simon
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, Erlangen 91052, Germany.
| | - Christine Sperber
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, Erlangen 91052, Germany; Division of Pharmaceutics, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, Erlangen 91058, Germany
| | - Cornelia Voigtländer
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, Erlangen 91052, Germany
| | - Julia Born
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, Erlangen 91052, Germany
| | - Daniel F Gilbert
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, Erlangen 91052, Germany
| | - Stefan Seyferth
- Division of Pharmaceutics, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, Erlangen 91058, Germany
| | - Geoffrey Lee
- Division of Pharmaceutics, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, Erlangen 91058, Germany
| | - Barbara Kappes
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, Erlangen 91052, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, Erlangen 91052, Germany.
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Kahl M, Gertig M, Hoyer P, Friedrich O, Gilbert DF. Ultra-Low-Cost 3D Bioprinting: Modification and Application of an Off-the-Shelf Desktop 3D-Printer for Biofabrication. Front Bioeng Biotechnol 2019; 7:184. [PMID: 31417899 PMCID: PMC6684753 DOI: 10.3389/fbioe.2019.00184] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [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: 05/29/2019] [Accepted: 07/15/2019] [Indexed: 01/01/2023] Open
Abstract
3D bioprinting has become a versatile and powerful method in tissue engineering and regenerative medicine and is increasingly adapted by other disciplines due to its tremendous potential beyond its typical applications. However, commercially available 3D bioprinting systems are typically expensive circumventing the broad implementation, including laboratories in low-resource settings. To address the limitations of conventional and commercially available technology, we developed a 3D bioprinter by modification of an off-the-shelf 3D desktop printer, that can be installed within a single day, is of handy size to fit into a standard laminar flow hood, customizable, ultra-low cost and thus, affordable to a broad range of research labs, or educational institutions. We evaluate accuracy and reproducibility of printing results using alginate and alginate/gelatin-hydrogels and demonstrate its potential for biomedical use by printing of various two-and three-dimensional cell-free and mammalian cell-laden objects using recombinant HEKYFP cells, stably expressing yellow fluorescent protein (YFP) as a model system and high-content imaging. We further provide a parts list and 3D design files in STL and STEP format for reconstructing the device. A time-lapse video of the custom-built device during operation is available at https://vimeo.com/274482794.
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Affiliation(s)
- Melanie Kahl
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Markus Gertig
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Phillipp Hoyer
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Daniel F Gilbert
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
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Schmitt MA, Friedrich O, Gilbert DF. Portoporator ©: A portable low-cost electroporation device for gene transfer to cultured cells in biotechnology, biomedical research and education. Biosens Bioelectron 2019; 131:95-103. [PMID: 30826656 DOI: 10.1016/j.bios.2019.02.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [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: 11/16/2018] [Revised: 02/03/2019] [Accepted: 02/10/2019] [Indexed: 01/15/2023]
Abstract
Electroporation has been a widely established method for delivering DNA and other material into cells in vitro. Conventional electroporation infrastructure is typically immobile, non-customizable, non-transparent regarding the characteristics of output pulses, and expensive. Here, we describe a portable electroporator for DNA delivery into bacterial cells that can quickly be reconstructed using 3D desktop printing and off-the-shelf components. The device is light weight (700 g), small (70 × 180 × 210 mm) and extremely low-cost (<EUR 130). We provide the electrical circuitry and a detailed parts list for rebuilding the device. We characterize the properties of generated pulses and apply the system for gene delivery into bacterial Dh5α cells. We analyze the transformation efficiency based on the optical density of cell suspensions at 595 nm and on quantitative analysis of images obtained from bacterial cell-grown agar plates using colony forming units as well as confluence as indicators. We demonstrate time-dependency of the transformation efficiency using single pulses of 500 V between 1 and 1000 ms duration and we show that commercially available electroporation cuvettes of 1 mm gap size reveal higher transformation rates compared to cuvettes with 2 mm gap. We benchmark the transformation efficiency obtained using our platform with data from a heat shock-based transformation protocol and with data from a commercially available electroporator and show that our system reveals comparable results as the other techniques in the applied configurations. While this work focuses on genetic manipulation of bacterial cells, the device may also be applicable for delivery of genetic material small molecule or nanomaterials into other cell types, including mammalian cells.
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Affiliation(s)
- Max A Schmitt
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Daniel F Gilbert
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
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8
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Gilbert DF, Mofrad SA, Friedrich O, Wiest J. Proliferation characteristics of cells cultured under periodic versus static conditions. Cytotechnology 2018; 71:443-452. [PMID: 30515656 DOI: 10.1007/s10616-018-0263-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [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: 04/17/2018] [Accepted: 09/27/2018] [Indexed: 12/13/2022] Open
Abstract
In vitro culture models have become an indispensable tool for assessing a vast variety of biological questions in many scientific fields. However, common in vitro cultures are maintained under static conditions, which do not reflect the in vivo situation and create a non-physiological environment. To assess whether the growth characteristics of cells cultured at pulsed-perfused versus static conditions differ, we observed the growth of differentially cultured cells in vitro by life-cell time-lapse imaging of recombinant HEK293YFPI152L cells, stably expressing yellow fluorescent protein. Cells were grown for ~ 30 h at 37 °C and ambient CO2 concentration in biochips mounted into a custom-designed 3D printed carrier and were imaged at a rate of ten images per hour using a fluorescence microscope with environment control infrastructure. Cells in one chip were maintained under static conditions whereas cells in another chip were recurrently perfused with fresh media. Generated image series were quantitatively analyzed using a custom-modified cell detection software. Imaging data averaged from four biological replicates per culturing condition demonstrate that cells cultured under conventional conditions exhibit an exponential growth rate. In contrast, cells cultured in periodic mode exhibited a non-exponential growth rate. Our data clearly indicate differential growth characteristics of cells cultured under periodic versus static conditions highlighting the impact of the culture conditions on the physiology of cells in vitro.
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Affiliation(s)
- Daniel F Gilbert
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany. .,Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
| | - Sepideh Abolpour Mofrad
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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9
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Scharin-Mehlmann M, Häring A, Rommel M, Dirnecker T, Friedrich O, Frey L, Gilbert DF. Nano- and Micro-Patterned S-, H-, and X-PDMS for Cell-Based Applications: Comparison of Wettability, Roughness, and Cell-Derived Parameters. Front Bioeng Biotechnol 2018; 6:51. [PMID: 29765941 PMCID: PMC5938557 DOI: 10.3389/fbioe.2018.00051] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [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: 01/18/2018] [Accepted: 04/16/2018] [Indexed: 12/12/2022] Open
Abstract
Polydimethylsiloxane (PDMS) is a promising biomaterial for generating artificial extracellular matrix (ECM) like patterned topographies, yet its hydrophobic nature limits its applicability to cell-based approaches. Although plasma treatment can enhance the wettability of PDMS, the surface is known to recover its hydrophobicity within a few hours after exposure to air. To investigate the capability of a novel PDMS-type (X-PDMS) for in vitro based assessment of physiological cell properties, we designed and fabricated plane as well as nano- and micrometer-scaled pillar-patterned growth substrates using the elastomer types S-, H- and X-PDMS, which were fabricated from commercially available components. Most importantly, we compared X-PDMS based growth substrates which have not yet been investigated in this context with H- as well as well-known S-PDMS based substrates. Due to its applicability to fabricating nanometer-sized topographic features with high accuracy and pattern fidelity, this material may be of high relevance for specific biomedical applications. To assess their applicability to cell-based approaches, we characterized the generated surfaces using water contact angle (WCA) measurement and atomic force microscopy (AFM) as indicators of wettability and roughness, respectively. We further assessed cell number, cell area and cellular elongation as indirect measures of cellular viability and adhesion by image cytometry and phenotypic profiling, respectively, using Calcein and Hoechst 33342 stained human foreskin fibroblasts as a model system. We show for the first time that different PDMS types are differently sensitive to plasma treatment. We further demonstrate that surface hydrophobicity changes along with changing height of the pillar-structures. Our data indicate that plane and structured X-PDMS shows cytocompatibility and adhesive properties comparable to the previously described elastomer types S- and H-PDMS. We conclude that nanometer-sized structuring of X-PDMS may serve as a powerful method for altering surface properties toward production of biomedical devices for cell-based applications.
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Affiliation(s)
- Marina Scharin-Mehlmann
- Chair of Electron Devices, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Aaron Häring
- Chair of Electron Devices, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Mathias Rommel
- Fraunhofer Institute for Integrated Systems and Device Technology (IISB), Erlangen, Germany
| | - Tobias Dirnecker
- Chair of Electron Devices, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Erlangen Graduate School in Advanced Optical Technologies (SAOT), Erlangen, Germany
| | - Lothar Frey
- Chair of Electron Devices, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Fraunhofer Institute for Integrated Systems and Device Technology (IISB), Erlangen, Germany.,Erlangen Graduate School in Advanced Optical Technologies (SAOT), Erlangen, Germany
| | - Daniel F Gilbert
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Erlangen Graduate School in Advanced Optical Technologies (SAOT), Erlangen, Germany
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Abstract
Glycine receptor chloride channels (GlyRs) are attractive drug targets for therapeutic intervention and are also more and more recognized in the context of in vitro neurotoxicity and developmental neurotoxicity testing. Assaying the functional properties of GlyR can serve as an indicator of cellular viability and the integrity of the developing and mature central nervous system. Human pluripotent NTERA-2 (NT2) stem cells undergo neuronal differentiation upon stimulation with retinoic acid and express a large variety of neuronal proteins-including GlyR. YFP-I152L, a halide-sensitive variant of yellow fluorescent protein, allows high-throughput fluorescence-based functional analysis of GlyRs in NT2 cells. Here we describe a protocol for phenotyping of cellular viability by functional analysis of GlyR in neuronally differentiated NT2 (NT2-N) cells using YFP-I152L as a reporter of functional integrity of GlyRs. The protocol describes neuronal differentiation of NT2 stem cells, transient transfection of NT2-N cells with YFP-I152L as well as functional imaging and analysis of data from high-content imaging.
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Affiliation(s)
- Katharina Kuenzel
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052, Erlangen, Germany.
| | - Sepideh Abolpour Mofrad
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052, Erlangen, Germany
| | - Daniel F Gilbert
- Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Institute of Medical Biotechnology, Paul-Gordan-Street 3, 91052, Erlangen, Germany
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11
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Menzner AK, Gilbert DF. A Protocol for In Vitro High-Throughput Chemical Susceptibility Screening in Differentiating NT2 Stem Cells. Methods Mol Biol 2018; 1601:61-70. [PMID: 28470517 DOI: 10.1007/978-1-4939-6960-9_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The incidence of neurological diseases including learning and developmental disorders has increased in recent years. Concurrently, the number and volume of worldwide registered and traded chemicals have also increased. There is a broad consensus that the developing brain is particularly sensitive to damage by chemicals and that evaluation of chemicals for developmental toxicity or neurotoxicity is critical to human health. Human pluripotent embryonal carcinoma (NTERA-2 or NT2) cells are increasingly considered as a suitable model for in vitro developmental toxicity and neurotoxicity (DT/DNT) studies as they undergo neuronal differentiation upon stimulation with retinoic acid (RA) and allow toxicity assessment at different stages of maturation. Here we describe a protocol for cell fitness screening in differentiating NT2 cells based on the analysis of intracellular ATP levels allowing for the identification of chemicals which are potentially harmful to the developing brain. The described method is suitable to be adapted to low-, medium-, and high-throughput screening and allows multiplexing with other cell fitness indicators. While the presented protocol focuses on cell fitness screening in human pluripotent stem cells it may also be applied to other in vitro models.
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Affiliation(s)
- Ann-Katrin Menzner
- Department of Internal Medicine 5, University Medical Center Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Daniel F Gilbert
- Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Institute of Medical Biotechnology, Paul-Gordan-Street 3, 91052, Erlangen, Germany.
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12
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Milanos S, Kuenzel K, Gilbert DF, Janzen D, Sasi M, Buettner A, Frimurer TM, Villmann C. Structural changes at the myrtenol backbone reverse its positive allosteric potential into inhibitory GABAA receptor modulation. Biol Chem 2018; 399:549-563. [DOI: 10.1515/hsz-2017-0262] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/24/2018] [Indexed: 02/07/2023]
Abstract
Abstract
GABAA receptors are ligand-gated anion channels that form pentameric arrangements of various subunits. Positive allosteric modulators of GABAA receptors have been reported as being isolated either from plants or synthesized analogs of known GABAA receptor targeting drugs. Recently, we identified monoterpenes, e.g. myrtenol as a positive allosteric modulator at α1β2 GABAA receptors. Here, along with pharmacophore-based virtual screening studies, we demonstrate that scaffold modifications of myrtenol resulted in the loss of modulatory activity. Two independent approaches, fluorescence-based compound analysis and electrophysiological recordings in whole-cell configurations were used for analysis of transfected cells. C-atoms 1 and 2 of the myrtenol backbone were identified as crucial to preserve positive allosteric potential. A modification at C-atom 2 and lack of the hydroxyl group at C-atom 1 exhibited significantly reduced GABAergic currents at α1β2, α1β2γ, α2β3, α2β3γ and α4β3δ receptors. This effect was independent of the γ2 subunit. A sub-screen with side chain length and volume differences at the C-atom 1 identified two compounds that inhibited GABAergic responses but without receptor subtype specificity. Our combined approach of pharmacophore-based virtual screening and functional readouts reveals that side chain modifications of the bridged six-membered ring structure of myrtenol are crucial for its modulatory potential at GABAA receptors.
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Affiliation(s)
- Sinem Milanos
- Institute for Clinical Neurobiology , Julius-Maximilians-Universität Würzburg , Versbacherstr. 5 , D-97078 Würzburg , Germany
- Department of Chemistry and Pharmacy, Food Chemistry, Emil-Fischer-Center , Friedrich-Alexander-Universität Erlangen-Nürnberg , D-90154 Erlangen , Germany
| | - Katharina Kuenzel
- Institute of Medical Biotechnology , Friedrich-Alexander-Universität Erlangen-Nürnberg , D-91052 Erlangen , Germany
| | - Daniel F. Gilbert
- Institute of Medical Biotechnology , Friedrich-Alexander-Universität Erlangen-Nürnberg , D-91052 Erlangen , Germany
| | - Dieter Janzen
- Institute for Clinical Neurobiology , Julius-Maximilians-Universität Würzburg , Versbacherstr. 5 , D-97078 Würzburg , Germany
| | - Manju Sasi
- Institute for Clinical Neurobiology , Julius-Maximilians-Universität Würzburg , Versbacherstr. 5 , D-97078 Würzburg , Germany
| | - Andrea Buettner
- Department of Chemistry and Pharmacy, Food Chemistry, Emil-Fischer-Center , Friedrich-Alexander-Universität Erlangen-Nürnberg , D-90154 Erlangen , Germany
- Department of Sensory Analytics , Fraunhofer-Institute for Process Engineering and Packaging , D-85354 Freising , Germany
| | - Thomas M. Frimurer
- Section for Metabolic Receptology, Novo Nordisk Foundation Center for Basic Metabolic Research , University of Copenhagen , Copenhagen , Denmark
| | - Carmen Villmann
- Institute for Clinical Neurobiology , Julius-Maximilians-Universität Würzburg , Versbacherstr. 5 , D-97078 Würzburg , Germany
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13
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Resheq YJ, Menzner AK, Bosch J, Tickle J, Li KK, Wilhelm A, Hepburn E, Murihead G, Ward ST, Curbishley SM, Zimmermann HW, Bruns T, Gilbert DF, Tripal P, Mackensen A, Adams DH, Weston CJ. Impaired Transmigration of Myeloid-Derived Suppressor Cells across Human Sinusoidal Endothelium Is Associated with Decreased Expression of CD13. J Immunol 2017; 199:1672-1681. [PMID: 28739875 DOI: 10.4049/jimmunol.1600466] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 06/22/2017] [Indexed: 12/14/2022]
Abstract
Human monocytic myeloid-derived suppressor cells (MO-MDSCs) within the hepatic compartment suppress inflammation and impair immune surveillance in liver cancer. It is currently not known whether recruitment of MO-MDSCs from blood via hepatic sinusoidal endothelium (HSEC) contributes to their enrichment within the hepatic compartment. We compared the transmigratory potential of MO-MDSCs and monocytes after adhesion to hepatic endothelial monolayers in flow-based assays that mimic in vivo shear stress in the sinusoids. Despite comparable binding to HSEC monolayers, proportionally fewer MO-MDSCs underwent transendothelial migration, indicating that the final steps of extravasation, where actin polymerization plays an important role, are impaired in MO-MDSCs. In this article, we found reduced levels of CD13 on MO-MDSCs, which has recently been reported to control cell motility in monocytes, alongside reduced VLA-4 expression, an integrin predominantly involved in adherence to the apical side of the endothelium. CD13 and VLA-4 blocking and activating Abs were used in flow-based adhesion assays, live-cell imaging of motility, and actin polymerization studies to confirm a role for CD13 in impaired MO-MDSC transmigration. These findings indicate that CD13 significantly contributes to tissue infiltration by MO-MDSCs and monocytes, thereby contributing to the pathogenesis of hepatic inflammation.
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Affiliation(s)
- Yazid J Resheq
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom; .,Department of Internal Medicine 5, Hematology/Oncology, University of Erlangen-Nuremberg, Erlangen 91054, Germany
| | - Ann-Katrin Menzner
- Department of Internal Medicine 5, Hematology/Oncology, University of Erlangen-Nuremberg, Erlangen 91054, Germany
| | - Jacobus Bosch
- Department of Internal Medicine 5, Hematology/Oncology, University of Erlangen-Nuremberg, Erlangen 91054, Germany
| | - Joseph Tickle
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Ka-Kit Li
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Annika Wilhelm
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.,Division of Digestive Diseases, Department of Surgery and Cancer, Imperial College London, London W2 1NY, United Kingdom
| | - Elizabeth Hepburn
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Gillian Murihead
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Stephen T Ward
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Stuart M Curbishley
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Henning W Zimmermann
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.,Department of Medicine III, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Tony Bruns
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.,Department of Medicine IV, University of Jena, 07743 Jena, Germany
| | - Daniel F Gilbert
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nuremberg, 91052 Erlangen, Germany; and
| | - Philipp Tripal
- Optical Imaging Centre Erlangen, Friedrich-Alexander-University Erlangen-Nuremberg, 91052 Erlangen, Germany
| | - Andreas Mackensen
- Department of Internal Medicine 5, Hematology/Oncology, University of Erlangen-Nuremberg, Erlangen 91054, Germany
| | - David H Adams
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Chris J Weston
- Institute of Immunology and Immunotherapy, Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Centre, College of Medicine and Dentistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
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14
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Gilbert DF, Stebbing MJ, Kuenzel K, Murphy RM, Zacharewicz E, Buttgereit A, Stokes L, Adams DJ, Friedrich O. Store-Operated Ca 2+ Entry (SOCE) and Purinergic Receptor-Mediated Ca 2+ Homeostasis in Murine bv2 Microglia Cells: Early Cellular Responses to ATP-Mediated Microglia Activation. Front Mol Neurosci 2016; 9:111. [PMID: 27840602 PMCID: PMC5083710 DOI: 10.3389/fnmol.2016.00111] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [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: 08/04/2016] [Accepted: 10/14/2016] [Indexed: 12/31/2022] Open
Abstract
Microglia activation is a neuroinflammatory response to parenchymal damage with release of intracellular metabolites, e.g., purines, and signaling molecules from damaged cells. Extracellular purines can elicit Ca2+-mediated microglia activation involving P2X/P2Y receptors with metabotropic (P2Y) and ionotropic (P2X) cell signaling in target cells. Such microglia activation results in increased phagocytic activity, activation of their inflammasome and release of cytokines to sustain neuroinflammatory (so-called M1/M2 polarization). ATP-induced activation of ionotropic P2X4 and P2X7 receptors differentially induces receptor-operated Ca2+ entry (ROCE). Although store-operated Ca2+ entry (SOCE) was identified to modulate ROCE in primary microglia, its existence and role in one of the most common murine microglia cell line, BV2, is unknown. To dissect SOCE from ROCE in BV2 cells, we applied high-resolution multiphoton Ca2+ imaging. After depleting internal Ca2+ stores, SOCE was clearly detectable. High ATP concentrations (1 mM) elicited sustained increases in intracellular [Ca2+]i whereas lower concentrations (≤100 μM) also induced Ca2+ oscillations. These differential responses were assigned to P2X7 and P2X4 activation, respectively. Pharmacologically inhibiting P2Y and P2X responses did not affect SOCE, and in fact, P2Y-responses were barely detectable in BV2 cells. STIM1S content was significantly upregulated by 1 mM ATP. As P2X-mediated Ca2+ oscillations were rare events in single cells, we implemented a high-content screening approach that allows to record Ca2+ signal patterns from a large number of individual cells at lower optical resolution. Using automated classifier analysis, several drugs (minocycline, U73122, U73343, wortmannin, LY294002, AZ10606120) were tested on their profile to act on Ca2+ oscillations (P2X4) and sustained [Ca2+]i increases. We demonstrate specific drug effects on purinergic Ca2+ pathways and provide new pharmacological insights into Ca2+ oscillations in BV2 cells. For example, minocycline inhibits both P2X7- and P2X4-mediated Ca2+-responses, and this may explain its anti-inflammatory action in neuroinflammatory disease. As a technical result, our novel automated bio-screening approach provides a biomedical engineering platform to allow high-content drug library screens to study neuro-inflammation in vitro.
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Affiliation(s)
- Daniel F Gilbert
- Department of Chemical and Biological Engineering, Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany
| | - Martin J Stebbing
- Health Innovations Research Institute, Royal Melbourne Institute of Technology University, Melbourne VIC, Australia
| | - Katharina Kuenzel
- Department of Chemical and Biological Engineering, Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany
| | - Robyn M Murphy
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne VIC, Australia
| | - Evelyn Zacharewicz
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne VIC, Australia
| | - Andreas Buttgereit
- Department of Chemical and Biological Engineering, Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg Erlangen, Germany
| | - Leanne Stokes
- Health Innovations Research Institute, Royal Melbourne Institute of Technology University, Melbourne VIC, Australia
| | - David J Adams
- Health Innovations Research Institute, Royal Melbourne Institute of Technology University, Melbourne VIC, Australia
| | - Oliver Friedrich
- Department of Chemical and Biological Engineering, Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany; Health Innovations Research Institute, Royal Melbourne Institute of Technology University, MelbourneVIC, Australia
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15
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Abolpour Mofrad S, Kuenzel K, Friedrich O, Gilbert DF. Optimizing neuronal differentiation of human pluripotent NT2 stem cells in monolayer cultures. Dev Growth Differ 2016; 58:664-676. [DOI: 10.1111/dgd.12323] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 08/05/2016] [Accepted: 08/21/2016] [Indexed: 01/04/2023]
Affiliation(s)
- Sepideh Abolpour Mofrad
- Institute of Medical Biotechnology; Friedrich-Alexander-Universität Erlangen-Nürnberg; Erlangen Germany
- Erlangen Graduate School in Optical Technologies (SAOT); Friedrich-Alexander-Universität Erlangen-Nürnberg; Paul-Gordan-Str. 6 91052 Erlangen Germany
| | - Katharina Kuenzel
- Institute of Medical Biotechnology; Friedrich-Alexander-Universität Erlangen-Nürnberg; Erlangen Germany
- Erlangen Graduate School in Optical Technologies (SAOT); Friedrich-Alexander-Universität Erlangen-Nürnberg; Paul-Gordan-Str. 6 91052 Erlangen Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology; Friedrich-Alexander-Universität Erlangen-Nürnberg; Erlangen Germany
- Erlangen Graduate School in Optical Technologies (SAOT); Friedrich-Alexander-Universität Erlangen-Nürnberg; Paul-Gordan-Str. 6 91052 Erlangen Germany
| | - Daniel F. Gilbert
- Institute of Medical Biotechnology; Friedrich-Alexander-Universität Erlangen-Nürnberg; Erlangen Germany
- Erlangen Graduate School in Optical Technologies (SAOT); Friedrich-Alexander-Universität Erlangen-Nürnberg; Paul-Gordan-Str. 6 91052 Erlangen Germany
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16
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Spitzer P, Condic M, Herrmann M, Oberstein TJ, Scharin-Mehlmann M, Gilbert DF, Friedrich O, Grömer T, Kornhuber J, Lang R, Maler JM. Amyloidogenic amyloid-β-peptide variants induce microbial agglutination and exert antimicrobial activity. Sci Rep 2016; 6:32228. [PMID: 27624303 PMCID: PMC5021948 DOI: 10.1038/srep32228] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 08/04/2016] [Indexed: 11/09/2022] Open
Abstract
Amyloid-β (Aβ) peptides are the main components of the plaques found in the brains of patients with Alzheimer's disease. However, Aβ peptides are also detectable in secretory compartments and peripheral blood contains a complex mixture of more than 40 different modified and/or N- and C-terminally truncated Aβ peptides. Recently, anti-infective properties of Aβ peptides have been reported. Here, we investigated the interaction of Aβ peptides of different lengths with various bacterial strains and the yeast Candida albicans. The amyloidogenic peptides Aβ1-42, Aβ2-42, and Aβ3p-42 but not the non-amyloidogenic peptides Aβ1-40 and Aβ2-40 bound to microbial surfaces. As observed by immunocytochemistry, scanning electron microscopy and Gram staining, treatment of several bacterial strains and Candida albicans with Aβ peptide variants ending at position 42 (Aβx-42) caused the formation of large agglutinates. These aggregates were not detected after incubation with Aβx-40. Furthermore, Aβx-42 exerted an antimicrobial activity on all tested pathogens, killing up to 80% of microorganisms within 6 h. Aβ1-40 only had a moderate antimicrobial activity against C. albicans. Agglutination of Aβ1-42 was accelerated in the presence of microorganisms. These data demonstrate that the amyloidogenic Aβx-42 variants have antimicrobial activity and may therefore act as antimicrobial peptides in the immune system.
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Affiliation(s)
- Philipp Spitzer
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen, Germany
| | - Mateja Condic
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen, Germany
| | - Martin Herrmann
- Department of Medicine III, Institute for Clinical Immunology, Friedrich-Alexander-University Erlangen-Nuremberg, Gluecksstraße 4a, D-91054 Erlangen, Germany
| | - Timo Jan Oberstein
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen, Germany
| | - Marina Scharin-Mehlmann
- Electron Devices, Friedrich-Alexander-University Erlangen-Nuremberg, Cauerstraße 6, D-91058 Erlangen, Germany
| | - Daniel F Gilbert
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nuremberg, Paul-Gordan-Str. 3, D-91052 Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nuremberg, Paul-Gordan-Str. 3, D-91052 Erlangen, Germany
| | - Teja Grömer
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen, Germany
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen, Germany
| | - Roland Lang
- Institute of Clinical Microbiology, Immunology and Hygiene, Friedrich-Alexander-University Erlangen-Nuremberg, Wasserturmstr. 3/5, D-91054 Erlangen, Germany
| | - Juan Manuel Maler
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen, Germany
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17
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Kuenzel K, Friedrich O, Gilbert DF. A Recombinant Human Pluripotent Stem Cell Line Stably Expressing Halide-Sensitive YFP-I152L for GABAAR and GlyR-Targeted High-Throughput Drug Screening and Toxicity Testing. Front Mol Neurosci 2016; 9:51. [PMID: 27445687 PMCID: PMC4923258 DOI: 10.3389/fnmol.2016.00051] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [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: 05/10/2016] [Accepted: 06/13/2016] [Indexed: 01/29/2023] Open
Abstract
GABAARs and GlyRs are considered attractive drug targets for therapeutic intervention and are also increasingly recognized in the context of in vitro neurotoxicity (NT) and developmental neurotoxicity (DNT) testing. However, systematic human-specific GABAAR and GlyR-targeted drug screening and toxicity testing is hampered due to lack of appropriate in vitro models that express native GABAARs and GlyRs. We have established a human pluripotent stem cell line (NT2) stably expressing YFP-I152L, a halide-sensitive variant of yellow fluorescent protein (YFP), allowing for fluorescence-based functional analysis of chloride channels. Upon stimulation with retinoic acid, NT2 cells undergo neuronal differentiation and allow pharmacological and toxicological evaluation of native GABAARs and GlyRs at different stages of brain maturation. We applied the cell line in concentration-response experiments with the neurotransmitters GABA and glycine as well as with the drugs strychnine, picrotoxin, fipronil, lindane, bicuculline, and zinc and demonstrate that the established in vitro model is applicable to GABAAR and GlyR-targeted pharmacological and toxicological profiling. We quantified the proportion of GABAAR and GlyR-sensitive cells, respectively, and identified percentages of approximately 20% each within the overall populations, rendering the cells a suitable model for systematic in vitro GABAAR and GlyR-targeted screening in the context of drug development and NT/DNT testing.
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Affiliation(s)
- Katharina Kuenzel
- Department of Chemical and Biological Engineering, Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany
| | - Oliver Friedrich
- Department of Chemical and Biological Engineering, Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany
| | - Daniel F Gilbert
- Department of Chemical and Biological Engineering, Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany; Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany
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18
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Börner K, Niopek D, Cotugno G, Kaldenbach M, Pankert T, Willemsen J, Zhang X, Schürmann N, Mockenhaupt S, Serva A, Hiet MS, Wiedtke E, Castoldi M, Starkuviene V, Erfle H, Gilbert DF, Bartenschlager R, Boutros M, Binder M, Streetz K, Kräusslich HG, Grimm D. Robust RNAi enhancement via human Argonaute-2 overexpression from plasmids, viral vectors and cell lines. Nucleic Acids Res 2013; 41:e199. [PMID: 24049077 PMCID: PMC3834839 DOI: 10.1093/nar/gkt836] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [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: 07/30/2013] [Revised: 08/21/2013] [Accepted: 08/25/2013] [Indexed: 12/31/2022] Open
Abstract
As the only mammalian Argonaute protein capable of directly cleaving mRNAs in a small RNA-guided manner, Argonaute-2 (Ago2) is a keyplayer in RNA interference (RNAi) silencing via small interfering (si) or short hairpin (sh) RNAs. It is also a rate-limiting factor whose saturation by si/shRNAs limits RNAi efficiency and causes numerous adverse side effects. Here, we report a set of versatile tools and widely applicable strategies for transient or stable Ago2 co-expression, which overcome these concerns. Specifically, we engineered plasmids and viral vectors to co-encode a codon-optimized human Ago2 cDNA along with custom shRNAs. Furthermore, we stably integrated this Ago2 cDNA into a panel of standard human cell lines via plasmid transfection or lentiviral transduction. Using various endo- or exogenous targets, we demonstrate the potential of all three strategies to boost mRNA silencing efficiencies in cell culture by up to 10-fold, and to facilitate combinatorial knockdowns. Importantly, these robust improvements were reflected by augmented RNAi phenotypes and accompanied by reduced off-targeting effects. We moreover show that Ago2/shRNA-co-encoding vectors can enhance and prolong transgene silencing in livers of adult mice, while concurrently alleviating hepatotoxicity. Our customizable reagents and avenues should broadly improve future in vitro and in vivo RNAi experiments in mammalian systems.
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Affiliation(s)
- Kathleen Börner
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Dominik Niopek
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Gabriella Cotugno
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Michaela Kaldenbach
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Teresa Pankert
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Joschka Willemsen
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Xian Zhang
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Nina Schürmann
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Stefan Mockenhaupt
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Andrius Serva
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Marie-Sophie Hiet
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Ellen Wiedtke
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Mirco Castoldi
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Vytaute Starkuviene
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Holger Erfle
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Daniel F. Gilbert
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Ralf Bartenschlager
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Michael Boutros
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Marco Binder
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Konrad Streetz
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Hans-Georg Kräusslich
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
| | - Dirk Grimm
- Department of Infectious Diseases, Virology, Heidelberg University Hospital, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany, Cluster of Excellence CellNetworks, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany, Department of Medicine III, University Hospital Aachen, Pauwelstrasse 30, D-52074 Aachen, Germany, Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany, Division Signaling and Functional Genomics, German Cancer Research Center, Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany, BioQuant, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany and Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, Heidelberg University Hospital, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany
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Jung J, Weisenburger S, Albert S, Gilbert DF, Friedrich O, Eulenburg V, Kornhuber J, Groemer TW. Performance of scientific cameras with different sensor types in measuring dynamic processes in fluorescence microscopy. Microsc Res Tech 2013; 76:835-43. [DOI: 10.1002/jemt.22236] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 03/19/2013] [Accepted: 04/26/2013] [Indexed: 11/09/2022]
Affiliation(s)
- Jasmin Jung
- Department of Psychiatry and Psychotherapy; Friedrich-Alexander-University of Erlangen-Nuremberg; Erlangen 91054 Germany
| | - Siegfried Weisenburger
- Nano-Optics Division, Max Planck Institute for the Science of Light; Erlangen 91058 Germany
| | - Sahradha Albert
- Department of Psychiatry and Psychotherapy; Friedrich-Alexander-University of Erlangen-Nuremberg; Erlangen 91054 Germany
| | - Daniel F. Gilbert
- Institute of Medical Biotechnology; Friedrich-Alexander-University of Erlangen-Nuremberg; Erlangen 91052 Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology; Friedrich-Alexander-University of Erlangen-Nuremberg; Erlangen 91052 Germany
| | - Volker Eulenburg
- Department of Biochemistry and Molecular Medicine; Friedrich-Alexander-University of Erlangen-Nuremberg; Erlangen 91054 Germany
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy; Friedrich-Alexander-University of Erlangen-Nuremberg; Erlangen 91054 Germany
| | - Teja W. Groemer
- Department of Psychiatry and Psychotherapy; Friedrich-Alexander-University of Erlangen-Nuremberg; Erlangen 91054 Germany
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Balansa W, Islam R, Gilbert DF, Fontaine F, Xiao X, Zhang H, Piggott AM, Lynch JW, Capon RJ. Australian marine sponge alkaloids as a new class of glycine-gated chloride channel receptor modulator. Bioorg Med Chem 2013; 21:4420-5. [PMID: 23685178 DOI: 10.1016/j.bmc.2013.04.061] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 04/10/2013] [Accepted: 04/18/2013] [Indexed: 11/30/2022]
Abstract
Chemical analysis of a specimen of the sponge Ianthella cf. flabelliformis returned two new sesquiterpene glycinyl lactams, ianthellalactams A (1) and B (2), the known sponge sesquiterpene dictyodendrillin (3) and its ethanolysis artifact ethyl dictyodendrillin (4), and five known sponge indole alkaloids, aplysinopsin (5), 8E-3'-deimino-3'-oxoaplysinopsin (6), 8Z-3'-deimino-3'-oxoaplysinopsin (7), dihydroaplysinopsin (8) and tubastrindole B (9). The equilibrated mixture 6/7 exhibited glycine-gated chloride channel receptor (GlyR) antagonist activity with a bias towards α3 over α1 GlyR, while tubastrindole B (9) exhibited a bias towards α1 over α3 GlyR. At low- to sub-micromolar concentrations, 9 was also a selective potentiator of α1 GlyR, with no effect on α3 GlyR-a pharmacology that could prove useful in the treatment of movement disorders such as spasticity and hyperekplexia. Our investigations into the GlyR modulatory properties of 1-9 were further supported by the synthesis of a number of structurally related indole alkaloids.
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Affiliation(s)
- Walter Balansa
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia
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Talwar S, Lynch JW, Gilbert DF. Fluorescence-based high-throughput functional profiling of ligand-gated ion channels at the level of single cells. PLoS One 2013; 8:e58479. [PMID: 23520514 PMCID: PMC3592791 DOI: 10.1371/journal.pone.0058479] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [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: 10/31/2012] [Accepted: 02/06/2013] [Indexed: 12/26/2022] Open
Abstract
Ion channels are involved in many physiological processes and are attractive targets for therapeutic intervention. Their functional properties vary according to their subunit composition, which in turn varies in a developmental and tissue-specific manner and as a consequence of pathophysiological events. Understanding this diversity requires functional analysis of ion channel properties in large numbers of individual cells. Functional characterisation of ligand-gated channels involves quantitating agonist and drug dose-response relationships using electrophysiological or fluorescence-based techniques. Electrophysiology is limited by low throughput and high-throughput fluorescence-based functional evaluation generally does not enable the characterization of the functional properties of each individual cell. Here we describe a fluorescence-based assay that characterizes functional channel properties at single cell resolution in high throughput mode. It is based on progressive receptor activation and iterative fluorescence imaging and delivers >100 dose-responses in a single well of a 384-well plate, using α1-3 homomeric and αβ heteromeric glycine receptor (GlyR) chloride channels as a model system. We applied this assay with transiently transfected HEK293 cells co-expressing halide-sensitive yellow fluorescent protein and different GlyR subunit combinations. Glycine EC50 values of different GlyR isoforms were highly correlated with published electrophysiological data and confirm previously reported pharmacological profiles for the GlyR inhibitors, picrotoxin, strychnine and lindane. We show that inter and intra well variability is low and that clustering of functional phenotypes permits identification of drugs with subunit-specific pharmacological profiles. As this method dramatically improves the efficiency with which ion channel populations can be characterized in the context of cellular heterogeneity, it should facilitate systems-level analysis of ion channel properties in health and disease and the discovery of therapeutics to reverse pathological alterations.
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Affiliation(s)
- Sahil Talwar
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Joseph W. Lynch
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Daniel F. Gilbert
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
- * E-mail:
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22
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Kuhns S, Schmidt KN, Reymann J, Gilbert DF, Neuner A, Hub B, Carvalho R, Wiedemann P, Zentgraf H, Erfle H, Klingmüller U, Boutros M, Pereira G. The microtubule affinity regulating kinase MARK4 promotes axoneme extension during early ciliogenesis. ACTA ACUST UNITED AC 2013; 200:505-22. [PMID: 23400999 PMCID: PMC3575539 DOI: 10.1083/jcb.201206013] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [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] [Indexed: 02/08/2023]
Abstract
A functional screen identified MARK4 as a positive regulator of axonemal extension and ciliogenesis via its interaction with the mother centriolar protein ODF2. Despite the critical contributions of cilia to embryonic development and human health, key regulators of cilia formation await identification. In this paper, a functional RNA interference–based screen linked 30 novel protein kinases with ciliogenesis. Of them, we have studied the role of the microtubule (MT)-associated protein/MT affinity regulating kinase 4 (MARK4) in depth. MARK4 associated with the basal body and ciliary axoneme in human and murine cell lines. Ultrastructural and functional analyses established that MARK4 kinase activity was required for initiation of axoneme extension. We identified the mother centriolar protein ODF2 as an interaction partner of MARK4 and showed that ODF2 localization to the centriole partially depended on MARK4. Our data indicated that, upon MARK4 or ODF2 knockdown, the ciliary program arrested before the complete removal of the CP110–Cep97 inhibitory complex from the mother centriole, suggesting that these proteins act at this level of axonemal extension. We propose that MARK4 is a critical positive regulator of early steps in ciliogenesis.
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Affiliation(s)
- Stefanie Kuhns
- Molecular Biology of Centrosomes and Cilia group, Department of Cell and Molecular Biology, Medical Faculty Mannheim, Heidelberg University, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
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23
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Balansa W, Islam R, Fontaine F, Piggott AM, Zhang H, Xiao X, Webb TI, Gilbert DF, Lynch JW, Capon RJ. Sesterterpene glycinyl-lactams: a new class of glycine receptor modulator from Australian marine sponges of the genus Psammocinia. Org Biomol Chem 2013; 11:4695-701. [DOI: 10.1039/c3ob40861b] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gilbert DF, Erdmann G, Zhang X, Fritzsche A, Demir K, Jaedicke A, Muehlenberg K, Wanker EE, Boutros M. A novel multiplex cell viability assay for high-throughput RNAi screening. PLoS One 2011; 6:e28338. [PMID: 22162763 PMCID: PMC3230607 DOI: 10.1371/journal.pone.0028338] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [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: 10/13/2011] [Accepted: 11/06/2011] [Indexed: 01/08/2023] Open
Abstract
Cell-based high-throughput RNAi screening has become a powerful research tool in addressing a variety of biological questions. In RNAi screening, one of the most commonly applied assay system is measuring the fitness of cells that is usually quantified using fluorescence, luminescence and absorption-based readouts. These methods, typically implemented and scaled to large-scale screening format, however often only yield limited information on the cell fitness phenotype due to evaluation of a single and indirect physiological indicator. To address this problem, we have established a cell fitness multiplexing assay which combines a biochemical approach and two fluorescence-based assaying methods. We applied this assay in a large-scale RNAi screening experiment with siRNA pools targeting the human kinome in different modified HEK293 cell lines. Subsequent analysis of ranked fitness phenotypes assessed by the different assaying methods revealed average phenotype intersections of 50.7±2.3%–58.7±14.4% when two indicators were combined and 40–48% when a third indicator was taken into account. From these observations we conclude that combination of multiple fitness measures may decrease false-positive rates and increases confidence for hit selection. Our robust experimental and analytical method improves the classical approach in terms of time, data comprehensiveness and cost.
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Affiliation(s)
- Daniel F Gilbert
- German Cancer Research Center (DKFZ), Division of Signaling and Functional Genomics and Heidelberg University, Department of Cell and Molecular Biology, Heidelberg, Germany.
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Edwards JN, Blackmore DG, Gilbert DF, Murphy RM, Launikonis BS. Store-operated calcium entry remains fully functional in aged mouse skeletal muscle despite a decline in STIM1 protein expression. Aging Cell 2011; 10:675-85. [PMID: 21418512 DOI: 10.1111/j.1474-9726.2011.00706.x] [Citation(s) in RCA: 21] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Store-operated Ca(2+) entry (SOCE) is a robust mechanism in skeletal muscle, supported by abundant STIM1 and Orai1 in the junctional membranes. The precise role of SOCE in skeletal muscle Ca(2+) homeostasis and excitation-contraction coupling remains to be defined. Regardless, it remains important to determine whether the function and capacity of SOCE changes in aged skeletal muscle. We identified an approximate 40% decline in the expression of the integral SOCE protein, stromal interacting molecule 1 (STIM1), but no such decline in its coupling partner, Orai1, in muscle fibers from aged mice. To determine whether this changed aspects of SOCE functionality in skeletal muscle in aged mice, Ca(2+) in the cytoplasm and t-system were continuously and simultaneously imaged on a confocal microscope during sarcoplasmic reticulum Ca(2+) release and compared to experiments under identical conditions using muscle fibers from young mice. Normal activation, deactivation, Ca(2+) influx, and spatiotemporal characteristics of SOCE were found to persist in skeletal muscle from aged mice. Thus, SOCE remains a robust mechanism in aged skeletal muscle despite the decline in STIM1 protein expression, suggesting STIM1 is in excess in young skeletal muscle.
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Affiliation(s)
- Joshua N Edwards
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
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Gebhardt FM, Mitrovic AD, Gilbert DF, Vandenberg RJ, Lynch JW, Dodd PR. Exon-skipping splice variants of excitatory amino acid transporter-2 (EAAT2) form heteromeric complexes with full-length EAAT2. J Biol Chem 2010; 285:31313-24. [PMID: 20688910 PMCID: PMC2951206 DOI: 10.1074/jbc.m110.153494] [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] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 08/02/2010] [Indexed: 12/12/2022] Open
Abstract
The glial transporter excitatory amino acid transporter-2 (EAAT2) is the main mediator of glutamate clearance in brain. The wild-type transporter (EAAT2wt) forms trimeric membrane complexes in which each protomer functions autonomously. Several EAAT2 variants are found in control and Alzheimer-diseased human brains; their expression increases with pathological severity. These variants might alter EAAT2wt-mediated transport by abrogating membrane trafficking, or by changing the configuration or functionality of the assembled transporter complex. HEK293 cells were transfected with EAAT2wt; EAAT2b, a C-terminal variant; or either of two exon-skipping variants: alone or in combination. Surface biotinylation studies showed that only the exon-7 deletion variant was not trafficked to the membrane when transfected alone, and that all variants could reach the membrane when co-transfected with EAAT2wt. Fluorescence resonance energy transfer (FRET) studies showed that co-transfected EAAT2wt and EAAT2 splice variants were expressed in close proximity. Glutamate transporter function was measured using a whole cell patch clamp technique, or by changes in membrane potential indexed by a voltage-sensitive fluorescent dye (FMP assay): the two methods gave comparable results. Cells transfected with EAAT2wt or EAAT2b showed glutamate-dependent membrane potential changes consistent with functional expression. Cells transfected with EAAT2 exon-skipping variants alone gave no response to glutamate. Co-transfection of EAAT2wt (or EAAT2b) and splice variants in various ratios significantly raised glutamate EC(50) and decreased Hill coefficients. We conclude that exon-skipping variants form heteromeric complexes with EAAT2wt or EAAT2b that traffic to the membrane but show reduced glutamate-dependent activity. This could allow glutamate to accumulate extracellularly and promote excitotoxicity.
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Affiliation(s)
| | - Ann D. Mitrovic
- the Discipline of Pharmacology and Bosch Institute, University of Sydney, Sydney 2006, Australia
| | - Daniel F. Gilbert
- the Queensland Brain Institute and School of Biomedical Sciences, University of Queensland, Brisbane 4072 and
| | - Robert J. Vandenberg
- the Discipline of Pharmacology and Bosch Institute, University of Sydney, Sydney 2006, Australia
| | - Joseph W. Lynch
- the Queensland Brain Institute and School of Biomedical Sciences, University of Queensland, Brisbane 4072 and
| | - Peter R. Dodd
- From the School of Chemistry and Molecular Biosciences and
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Balansa W, Islam R, Fontaine F, Piggott AM, Zhang H, Webb TI, Gilbert DF, Lynch JW, Capon RJ. Ircinialactams: subunit-selective glycine receptor modulators from Australian sponges of the family Irciniidae. Bioorg Med Chem 2010; 18:2912-9. [PMID: 20346682 DOI: 10.1016/j.bmc.2010.03.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Revised: 03/02/2010] [Accepted: 03/03/2010] [Indexed: 11/26/2022]
Abstract
Screening an extract library of >2500 southern Australian and Antarctic marine invertebrates and algae for modulators of glycine receptor (GlyR) chloride channels identified three Irciniidae sponges that yielded new examples of a rare class of glycinyl lactam sesterterpene, ircinialactam A, 8-hydroxyircinialactam A, 8-hydroxyircinialactam B, ircinialactam C, ent-ircinialactam C and ircinialactam D. Structure-activity relationship (SAR) investigations revealed a new pharmacophore with potent and subunit selective modulatory properties against alpha1 and alpha3 GlyR isoforms. Such GlyR modulators have potential application as pharmacological tools, and as leads for the development of GlyR targeting therapeutics to treat chronic inflammatory pain, epilepsy, spasticity and hyperekplexia.
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Affiliation(s)
- Walter Balansa
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia
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28
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Gilbert DF, Islam R, Lynagh T, Lynch JW, Webb TI. High Throughput Techniques for Discovering New Glycine Receptor Modulators and their Binding Sites. Front Mol Neurosci 2009; 2:17. [PMID: 19949449 PMCID: PMC2782790 DOI: 10.3389/neuro.02.017.2009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [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: 07/23/2009] [Accepted: 09/27/2009] [Indexed: 11/13/2022] Open
Abstract
The inhibitory glycine receptor (GlyR) is a member of the Cys-loop receptor family that mediates inhibitory neurotransmission in the central nervous system. These receptors are emerging as potential drug targets for inflammatory pain, immunomodulation, spasticity and epilepsy. Antagonists that specifically inhibit particular GlyR isoforms are also required as pharmacological probes for elucidating the roles of particular GlyR isoforms in health and disease. Although a substantial number of both positive and negative GlyR modulators have been identified, very few of these are specific for the GlyR over other receptor types. Thus, the potential of known compounds as either therapeutic leads or pharmacological probes is limited. It is therefore surprising that there have been few published studies describing attempts to discover novel GlyR isoform-specific modulators. The first aim of this review is to consider various methods for efficiently screening compounds against these receptors. We conclude that an anion sensitive yellow fluorescent protein is optimal for primary screening and that automated electrophysiology of cells stably expressing GlyRs is useful for confirming hits and quantitating the actions of identified compounds. The second aim of this review is to demonstrate how these techniques are used in our laboratory for the purpose of both discovering novel GlyR-active compounds and characterizing their binding sites. We also describe a reliable, cost effective method for transfecting HEK293 cells in single wells of a 384-well plate using nanogram quantities of plasmid DNA.
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Affiliation(s)
- Daniel F Gilbert
- Queensland Brain Institute, The University of Queensland Brisbane, QLD, Australia
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29
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Abstract
In this article, the authors describe the image analysis software DetecTiff, which allows fully automated object recognition and quantification from digital images. The core module of the LabView-based routine is an algorithm for structure recognition that employs intensity thresholding and size-dependent particle filtering from microscopic images in an iterative manner. Detected structures are converted into templates, which are used for quantitative image analysis. DetecTiff enables processing of multiple detection channels and provides functions for template organization and fast interpretation of acquired data. The authors demonstrate the applicability of DetecTiff for automated analysis of cellular uptake of fluorescence-labeled low-density lipoproteins as well as diverse other image data sets from a variety of biomedical applications. Moreover, the performance of DetecTiff is compared with preexisting image analysis tools. The results show that DetecTiff can be applied with high consistency for automated quantitative analysis of image data (e.g., from large-scale functional RNAi screening projects).
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30
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Gilbert DF, Wilson JC, Nink V, Lynch JW, Osborne GW. Multiplexed labeling of viable cells for high-throughput analysis of glycine receptor function using flow cytometry. Cytometry A 2009; 75:440-9. [DOI: 10.1002/cyto.a.20703] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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