40 results on '"Markus Breunig"'
Search Results
2. Protocol to use de-epithelialized porcine urinary bladder as a tissue scaffold for propagation of pancreatic cells
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Michael Karl Melzer, Markus Breunig, Paul Lopatta, Meike Hohwieler, Sarah Merz, Anca Azoitei, Cagatay Günes, Christian Bolenz, and Alexander Kleger
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Cell culture ,Stem Cells ,Cell Differentiation ,Tissue Engineering ,Material sciences ,Science (General) ,Q1-390 - Abstract
Summary: Ex vivo organ culture can be a useful alternative to in vivo models, which can be time-, labor-, and cost-intensive. Here we describe a step-by-step protocol to use de-epithelialized porcine urinary bladders as scaffolds in air-liquid interface in vitro culture systems for a variety of pluripotent stem-cell-derived and patient-derived pancreatic cells and organoids. The scaffold can trigger cell maturation and enable cell-cell interaction and invasion capacity studies. However, this model is limited by the lack of functional vasculature.For complete details on the use and execution of this protocol, please refer to Melzer et al. (2022),1 Breunig et al. (2021),2 and Breunig et al. (2021).3 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
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- 2022
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3. Differentiation of human pluripotent stem cells into pancreatic duct-like organoids
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Markus Breunig, Jessica Merkle, Michael Karl Melzer, Sandra Heller, Thomas Seufferlein, Matthias Meier, Meike Hohwieler, and Alexander Kleger
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Cell culture ,Developmental biology ,Stem Cells ,Cell Differentiation ,Organoids ,Science (General) ,Q1-390 - Abstract
Summary: The recapitulation of human developmental processes and pathological manifestations requires access to specific cell types and precursor stages during embryogenesis and disease. Here, we describe a scalable in vitro differentiation protocol to guide human pluripotent stem cells stepwise into pancreatic duct-like organoids. The protocol mimics pancreatic duct development and was successfully used to model the onset and progression of pancreatic ductal adenocarcinoma; the approach is suitable for multiple downstream applications. However, the protocol is cost- and time-intensive.For complete details on the use and execution of this protocol, please refer to Breunig et al. (2021).
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- 2021
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4. Functional Genomic Screening in Human Pluripotent Stem Cells Reveals New Roadblocks in Early Pancreatic Endoderm Formation
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Jana Krüger, Markus Breunig, Lino Pascal Pasquini, Mareen Morawe, Alexander Groß, Frank Arnold, Ronan Russell, Thomas Seufferlein, Ninel Azoitei, Hans A. Kestler, Cécile Julier, Sandra Heller, Meike Hohwieler, and Alexander Kleger
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stem cells ,pancreatic development ,definitive endoderm ,shRNA ,Cytology ,QH573-671 - Abstract
Human pluripotent stem cells, with their ability to proliferate indefinitely and to differentiate into virtually all cell types of the human body, provide a novel resource to study human development and to implement relevant disease models. Here, we employed a human pancreatic differentiation platform complemented with an shRNA screen in human pluripotent stem cells (PSCs) to identify potential drivers of early endoderm and pancreatic development. Deep sequencing followed by abundancy ranking pinpointed six top hit genes potentially associated with either improved or impaired endodermal differentiation, which were selected for functional validation in CRISPR-Cas9 mediated knockout (KO) lines. Upon endoderm differentiation (DE), particularly the loss of SLC22A1 and DSC2 led to impaired differentiation efficiency into CXCR4/KIT-positive DE cells. qPCR analysis also revealed changes in differentiation markers CXCR4, FOXA2, SOX17, and GATA6. Further differentiation of PSCs to the pancreatic progenitor (PP) stage resulted in a decreased proportion of PDX1/NKX6-1-positive cells in SLC22A1 KO lines, and in DSC2 KO lines when differentiated under specific culture conditions. Taken together, our study reveals novel genes with potential roles in early endodermal development.
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- 2022
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5. Pancreatic Ductal Organoids React Kras Dependent to the Removal of Tumor Suppressive Roadblocks
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Lukas Perkhofer, Melanie Engler, Johann Gout, Frank Arnold, Mareen Morawe, Markus Breunig, Thomas Seufferlein, Alexander Kleger, and Pierre-Olivier Frappart
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Internal medicine ,RC31-1245 - Abstract
Pancreatic ductal adenocarcinoma (PDAC) is still the Achilles heel in modern oncology, with an increasing incidence accompanied by a persisting high mortality. The developmental process of PDAC is thought to be stepwise via precursor lesions and sequential accumulation of mutations. Thereby, current sequencing studies recapitulate this genetic heterogeneity in PDAC and show besides a handful of driver mutations (KRAS, TP53) a plethora of passenger mutations that allow to define subtypes. However, modeling the mutations of interest and their effects is still challenging. Interestingly, organoids have the potential to recapitulate in vitro, the in vivo characteristics of the tissue they originate from. Here, we could establish and develop tools allowing us to isolate, culture, and genetically modify ductal mouse organoids. Transferred to known effectors in the IPMN-PDAC sequence, we could reveal significantly increased proliferative and self-renewal capacities for PTEN and RNF43 deficiency in the context of oncogenic KRASG12D in mouse pancreatic organoids. Overall, we were able to obtain promising data centering ductal organoids in the focus of future PDAC research.
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- 2019
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6. TanDEM-X Water Indication Mask: Generation and First Evaluation Results
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Anna Wendleder, Birgit Wessel, Achim Roth, Markus Breunig, Klaus Martin, and Susanne Wagenbrenner
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Amplitude ,coherence ,DEM editing ,TanDEM-X ,water body detection ,Ocean engineering ,TC1501-1800 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
The German SAR interferometry mission TanDEM-X performed on two TerraSAR-X satellites flying in close formation will provide a global Digital Elevation Model (DEM). A by-product is so-called the Water Indication Mask (WAM). The purpose of this supplementary information layer is to support the DEM editing process. Water surfaces usually show lower coherence in an interferometric data set due to temporal de-correlation and low backscattering. Consequently the corresponding elevation values derived from the interferogram are random and produce a virtual relief. This paper introduces the operational water body detection workflow that synergistically evaluates amplitude and coherence information. The presented results of two test sites reveal that the methodology is globally applicable, classifications are highly accurate and the algorithm is appropriate for operational image processing. The water body detection consists of two steps: the Water Body Detection (WBD) derived of one single DEM scene and the mosaicking of multiple WBD to a single Water Indication Mask (WAM). The fusion strategy for the final TanDEM-X WAM considers all WBD acquired at different times in two global coverages and bases on a fusion by union containing the results of the amplitude and the coherence.
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- 2013
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7. Validation of the absolute height accuracy of TanDEM-X DEM for moderate terrain.
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Birgit Wessel, Astrid Gruber, Martin Huber 0002, Markus Breunig, Susanne Wagenbrenner, Anna Wendleder, and Achim Roth
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- 2014
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8. Transcriptional changes and the role of ONECUT1 in hPSC pancreatic differentiation
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Gopika G. Nair, Alexander Kleger, Ivan G. Costa, Cécile Julier, Meike Hohwieler, Matthias Hebrok, Thomas Seufferlein, Zhijian Li, Xi Zhang, Ryan J Geusz, Markus Breunig, Maike Sander, Sandra Heller, and Qiong Lin
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Transcription, Genetic ,Human Embryonic Stem Cells ,Regenerative Medizin ,Stem Cell Research - Embryonic - Non-Human ,Medicine (miscellaneous) ,Stem cells ,Transcriptome ,0302 clinical medicine ,DDC 570 / Life sciences ,Developmental ,Biology (General) ,Induced pluripotent stem cell ,Cancer ,0303 health sciences ,Stem Cell Research - Induced Pluripotent Stem Cell - Human ,High-throughput screening ,Gene Expression Regulation, Developmental ,Cell Differentiation ,Chromatin ,Cell biology ,Hepatocyte Nuclear Factor 6 ,medicine.anatomical_structure ,Differentiation ,Regenerative medicine ,General Agricultural and Biological Sciences ,Pancreas ,Transcription ,Cell type ,endocrine system ,QH301-705.5 ,1.1 Normal biological development and functioning ,Stem-cell differentiation ,Biology ,Article ,General Biochemistry, Genetics and Molecular Biology ,Cell Line ,Pancreatic Cancer ,03 medical and health sciences ,Rare Diseases ,Genetic ,Pluripotent stem cells ,Underpinning research ,ddc:570 ,Genetics ,medicine ,Humans ,Tissue engineering ,ddc:610 ,Epigenetics ,Stem Cell Research - Embryonic - Human ,Progenitor cell ,Transcription factor ,030304 developmental biology ,Stem Cell Research - Induced Pluripotent Stem Cell ,Stem Cell Research ,Gene Expression Regulation ,Cardiovascular and Metabolic Diseases ,Induzierte pluripotente Stammzelle ,Digestive Diseases ,DDC 610 / Medicine & health ,030217 neurology & neurosurgery - Abstract
Cell type specification during pancreatic development is tightly controlled by a transcriptional and epigenetic network. The precise role of most transcription factors, however, has been only described in mice. To convey such concepts to human pancreatic development, alternative model systems such as pancreatic in vitro differentiation of human pluripotent stem cells can be employed. Here, we analyzed stage-specific RNA-, ChIP-, and ATAC-sequencing data to dissect transcriptional and regulatory mechanisms during pancreatic development. Transcriptome and open chromatin maps of pancreatic differentiation from human pluripotent stem cells provide a stage-specific pattern of known pancreatic transcription factors and indicate ONECUT1 as a crucial fate regulator in pancreas progenitors. Moreover, our data suggest that ONECUT1 is also involved in preparing pancreatic progenitors for later endocrine specification. The dissection of the transcriptional and regulatory circuitry revealed an important role for ONECUT1 within such network and will serve as resource to study human development and disease., Heller et al analyze transcriptomic and epigenetic datasets from human PSCs differentiating into pancreatic progenitors to elucidate the regulatory mechanisms behind pancreatic development. The authors report that the transcription factor ONECUT1 is expressed specifically in pancreatic development and associates with other key TFs (such as FOXA2, GATA6, PDX1) during endocrine specification.
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- 2021
9. Normalization of TanDEM-X DSM Data in Urban Environments With Morphological Filters.
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Christian Geiss, Michael Wurm, Markus Breunig, Andreas Felbier, and Hannes Taubenböck
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- 2015
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10. The approach for combining dem acquisitions for the TanDEM-X dem mosaic.
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Astrid Gruber, Birgit Wessel, Martin Huber 0002, Markus Breunig, and Susanne Wagenbrenner
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- 2013
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11. Identification and characterization of urban structures using VHR SAR data.
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Thomas Esch, Martin Schmidt 0008, Markus Breunig, Andreas Felbier, Hannes Taubenböck, Wieke Heldens, Christian Riegler, Achim Roth, and Stefan W. Dech
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- 2011
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12. Production chain towards first calibrated and mosaicked TanDEM-X DEMs.
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Birgit Wessel, Astrid Gruber, Anna Wendleder, Martin Huber 0002, Markus Breunig, Ursula Marschalk, Detlev Kosmann, and Achim Roth
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- 2011
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13. Water body detection from TanDEM-X data: Concept and first evaluation of an accurate water indication mask.
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Anna Wendleder, Markus Breunig, Klaus Martin, Birgit Wessel, and Achim Roth
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- 2011
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14. Validation of tie-point concepts by the DEM adjustment approach of TanDEM-X.
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Martin Huber 0002, Astrid Gruber, Birgit Wessel, Markus Breunig, and Anna Wendleder
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- 2010
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15. Single-cell-resolved differentiation of human induced pluripotent stem cells into pancreatic duct-like organoids on a microwell chip
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Sandra Wiedenmann, Stefanie M. Hauck, Alexander Kleger, Michael Sterr, Thomas Seufferlein, Markus Breunig, Peter Möller, J Merkle, Meike Hohwieler, Christine von Toerne, Michel Moussus, Stephanie E. Weissinger, Tihomir Georgiev, Matthias Meier, Lucas A. Schulte, and Heiko Lickert
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Cell type ,Filamins ,Induced Pluripotent Stem Cells ,Cell ,Biomedical Engineering ,Cystic Fibrosis Transmembrane Conductance Regulator ,Medicine (miscellaneous) ,Bioengineering ,Mice, SCID ,Biology ,Immunofluorescence ,Mice ,Mice, Inbred NOD ,Lab-On-A-Chip Devices ,Biomarkers, Tumor ,medicine ,Organoid ,Animals ,Humans ,Progenitor cell ,Pancreatic duct ,medicine.diagnostic_test ,Mucins ,Pancreatic Ducts ,Cell Differentiation ,Cellular Reprogramming ,Cystic fibrosis transmembrane conductance regulator ,Computer Science Applications ,Cell biology ,Organoids ,Pancreatic Neoplasms ,Survival Rate ,medicine.anatomical_structure ,Hepatic stellate cell ,biology.protein ,Single-Cell Analysis ,Biotechnology - Abstract
Creating in vitro models of diseases of the pancreatic ductal compartment requires a comprehensive understanding of the developmental trajectories of pancreas-specific cell types. Here we report the single-cell characterization of the differentiation of pancreatic duct-like organoids (PDLOs) from human induced pluripotent stem cells (hiPSCs) on a microwell chip that facilitates the uniform aggregation and chemical induction of hiPSC-derived pancreatic progenitors. Using time-resolved single-cell transcriptional profiling and immunofluorescence imaging of the forming PDLOs, we identified differentiation routes from pancreatic progenitors through ductal intermediates to two types of mature duct-like cells and a few non-ductal cell types. PDLO subpopulations expressed either mucins or the cystic fibrosis transmembrane conductance regulator, and resembled human adult duct cells. We also used the chip to uncover ductal markers relevant to pancreatic carcinogenesis, and to establish PDLO co-cultures with stellate cells, which allowed for the study of epithelial-mesenchymal signalling. The PDLO microsystem could be used to establish patient-specific pancreatic duct models.
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- 2021
16. Modeling plasticity and dysplasia of pancreatic ductal organoids derived from human pluripotent stem cells
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Zahra Dantes, Maximilian Reichert, József Maléth, Thomas Engleitner, Thomas Seufferlein, MK Melzer, Christian M. Cohrs, J Merkle, Martin Wagner, Martin Müller, Tamara Madácsy, Joscha Griger, Cagatay Günes, Stefan Liebau, Markus Breunig, Matthias Meier, Thomas F. E. Barth, Sandra Wiedenmann, Patrick C. Hermann, Stephan Speier, Bernhard Kuster, Sandra Heller, Maximilian Schmid, Gaurav Jain, Pamela Gehron Robey, Johannes Krumm, Florian Kuhn, Lukas Perkhofer, Christian Bolenz, Oliver Wessely, Alexander Kleger, Bence Sipos, Árpád Varga, Ninel Azoitei, Roland Rad, Jana Krüger, and Meike Hohwieler
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Pluripotent Stem Cells ,Proteomics ,03. Orvos- és egészségtudomány ,medicine.disease_cause ,Article ,03 medical and health sciences ,Mice ,0302 clinical medicine ,CDKN2A ,Genetics ,GNAS complex locus ,medicine ,Animals ,Humans ,Induced pluripotent stem cell ,030304 developmental biology ,0303 health sciences ,biology ,Pancreatic Ducts ,01.06. Biológiai tudományok ,Cell Biology ,medicine.disease ,digestive system diseases ,3. Good health ,Transplantation ,Organoids ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Dysplasia ,Cdkn2a ,Gnas ,Ipmn ,Kras ,Pdac ,Disease Modelling ,Ductal Pancreatic Organoids ,Human Pluripotent Stem Cells ,In Vitro Differentiation ,Xenograft ,Mutation ,Cancer research ,biology.protein ,Molecular Medicine ,KRAS ,Carcinogenesis ,Pancreas ,030217 neurology & neurosurgery ,Carcinoma, Pancreatic Ductal - Abstract
Personalized invitro models for dysplasia and carcinogenesis in the pancreas have been constrained by insufficient differentiation of human pluripotent stem cells (hPSCs) into the exocrine pancreatic lineage. Here, we differentiate hPSCs into pancreatic duct-like organoids (PDLOs) with morphological, transcriptional, proteomic, and functional characteristics of human pancreatic ducts, further maturing upon transplantation into mice. PDLOs are generated from hPSCs inducibly expressing oncogenic GNAS, KRAS, or KRAS with genetic covariance of lost CDKN2A and from induced hPSCs derived from a McCune-Albright patient. Each oncogene causes a specific growth, structural, and molecular phenotype invitro. While transplanted PDLOs with oncogenic KRAS alone form heterogenous dysplastic lesions or cancer, KRAS with CDKN2A loss develop dedifferentiated pancreatic ductal adenocarcinomas. In contrast, transplanted PDLOs with mutant GNAS lead to intraductal papillary mucinous neoplasia-like structures. Conclusively, PDLOs enable invitro and invivo studies of pancreatic plasticity, dysplasia, and cancer formation from a genetically defined background.
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- 2021
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17. Organoids at the PUB: The Porcine Urinary Bladder Serves as a Pancreatic Niche for Advanced Cancer Modeling
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Michael Karl Melzer, Markus Breunig, Frank Arnold, Felix Wezel, Anca Azoitei, Elodie Roger, Jana Krüger, Jessica Merkle, Lena Schütte, Yazid Resheq, Mark Hänle, Viktor Zehe, Friedemann Zengerling, Ninel Azoitei, Lukas Klein, Frederike Penz, Shiv K. Singh, Thomas Seufferlein, Meike Hohwieler, Christian Bolenz, Cagatay Günes, Johann Gout, and Alexander Kleger
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Organoid ,Pancreas ,Cancer ,Pancreatic neoplasms ,Swine ,Organ culture techniques ,pancreatic cancer ,Biomedical Engineering ,Zelldifferenzierung ,Pharmaceutical Science ,organ culture models ,Urinary bladder ,Organoids ,Biomaterials ,Pluripotent stem cells ,Induzierte pluripotente Stammzelle ,Cell differentiation ,Organkultur ,Animals ,Humans ,ddc:610 ,stem cell differentiation ,Bauchspeicheldrüsenkrebs ,DDC 610 / Medicine & health ,Carcinoma, Pancreatic Ductal - Abstract
Despite intensive research and progress in personalized medicine, pancreatic ductal adenocarcinoma remains one of the deadliest cancer entities. Pancreatic duct-like organoids (PDLOs) derived from human pluripotent stem cells (PSCs) or pancreatic cancer patient-derived organoids (PDOs) provide unique tools to study early and late stage dysplasia and to foster personalized medicine. However, such advanced systems are neither rapidly nor easily accessible and require an in vivo niche to study tumor formation and interaction with the stroma. Here, the establishment of the porcine urinary bladder (PUB) is revealed as an advanced organ culture model for shaping an ex vivo pancreatic niche. This model allows pancreatic progenitor cells to enter the ductal and endocrine lineages, while PDLOs further mature into duct-like tissue. Accordingly, the PUB offers an ex vivo platform for earliest pancreatic dysplasia and cancer if PDLOs feature KRASG12D mutations. Finally, it is demonstrated that PDOs-on-PUB i) resemble primary pancreatic cancer, ii) preserve cancer subtypes, iii) enable the study of niche epithelial crosstalk by spiking in pancreatic stellate and immune cells into the grafts, and finally iv) allow drug testing. In summary, the PUB advances the existing pancreatic cancer models by adding feasibility, complexity, and customization at low cost and high flexibility., publishedVersion
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- 2022
18. SARS-CoV-2 infects cells of the human exocrine and endocrine pancreas and interferes with beta-cell function
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Lennart Koepke, Sandra Heller, Paul Walther, Jana Krüger, Markus Breunig, Albrecht Stenzinger, Jan Münch, Steffen Stenger, Michael Schuster, Isabel M Wessbecher, Ivan G. Costa, Alexander Kleger, Janis A. Müller, Patrick E. MacDonald, Caterina Prelli Bozzo, Manfred Frick, Stefan Liebau, Julia Gehrmann, Tatjana Weil, Johannes Steinhart, Thomas Seufferlein, Joanne van Vuuren, Thomas F. E. Barth, Tim Eiseler, Frank Kirchhoff, Clarissa Read, Konstantin M. J. Sparrer, Martin Wagner, Rüdiger Groß, Heiko Lickert, Carina Conzelmann, and Giorgio Fois
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medicine.anatomical_structure ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,medicine ,Beta-cell Function ,Endocrine system ,Biology ,Pancreas ,Virology - Abstract
Preexisting diabetes increases the risk of a severe course of the pandemic coronavirus disease 2019 (COVID-19). Vice versa, exacerbations of a preexisting diabetes as well as new-onset diabetes have been reported upon SARS-CoV-2 infection. Thus, there is an imperative need to clarify whether human pancreatic endocrine cells organized within an islet of Langerhans are permissive for and affected by SARS-CoV-2 infection, and to elucidate the mechanisms underlying the development of diabetes upon COVID-19. Here, we (i) defined ACE2 and TMPRSS2 expression patterns in human pancreatic endocrine and exocrine cell types, (ii) employed human pancreatic islet cultures to demonstrate susceptibility to SARS-CoV-2 infection and to viral replication in β-cells, (iii) showed that SARS-CoV-2 attenuates glucose-stimulated insulin secretion, and (iv) tested remdesivir as eventually effective to prevent β-cell failure. In addition, we (v) visualized viral particles replicating in endocrine pancreatic cells and define their subcellular localization patterns via transmission electron microscopy, and finally (vi) present examples of cell type specific pancreatic infection patterns of COVID-19 deceased patients. Overall, our data demonstrate that SARS-CoV-2 can infect both the exocrine and endocrine compartments of the pancreas and can perturb β-cell integrity, which might lead to an increased risk for diabetes.
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- 2020
19. Reconstruction of regulatory networks to predict gene function in pancreatic development and disease
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Julian D. Schwab, Sandra Heller, Markus Breunig, Hans A. Kestler, and Alexander Kleger
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Disease ,Computational biology ,Biology ,Gene ,Function (biology) - Published
- 2020
20. McCune-Albright syndrome and IPMN formation modelled in GNAS-mutated duct-like organoids derived from human pluripotent stem cells
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Alexander Kleger, Patrick C. Hermann, Sandra Heller, Thomas Seufferlein, Martin Müller, Markus Breunig, MK Melzer, M Meier, J Merkle, Martin Wagner, Lukas Perkhofer, and Meike Hohwieler
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medicine.anatomical_structure ,medicine ,Organoid ,Cancer research ,GNAS complex locus ,biology.protein ,Biology ,medicine.disease ,Induced pluripotent stem cell ,Duct (anatomy) ,McCune–Albright syndrome - Published
- 2020
21. Functional genomics to identify regulators of pancreatic commitment from human pluripotent stem cells
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Jana Krüger, L Pasquini, Markus Breunig, MK Melzer, S Heller, M Morawe, A Kleger, M Müller, and T Seufferlein
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Computational biology ,Biology ,Induced pluripotent stem cell ,Functional genomics - Published
- 2020
22. HNF6 in human pancreatic duct development
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J Merkle, Alexander Kleger, MK Melzer, Martin Müller, Sandra Heller, and Markus Breunig
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Pancreatic duct ,Pathology ,medicine.medical_specialty ,medicine.anatomical_structure ,business.industry ,medicine ,business - Published
- 2020
23. Mutations and variants of ONECUT1 in diabetes
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Eric Simon, Meike Hohwieler, Claire Dandine-Roulland, Stefan Liebau, Robert Olaso, Anett Illing, Bernhard Kuster, Xi Zhang, Maike Sander, Céline Besse, Ivan G. Costa, Jacqueline R. Benthuysen, Jean-François Deleuze, Martin Wagner, Johannes Krumm, Michael Schuster, Cécile Julier, Bernhard O. Boehm, Kyle J. Gaulton, Sandra Heller, Pierre Zalloua, Joshua Chiou, Gino Kwon, Valérie Senée, Gopika G. Nair, Allen Wang, Heike Neubauer, Qiong Lin, Alexander Kleger, Franz Oswald, Ryan J Geusz, Thomas Seufferlein, Anne Philippi, Thomas Klein, Marc Nicolino, Markus Breunig, Anne Degavre, Ronan Russell, Matthias Hebrok, and Zhijian Li
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Male ,Multifactorial Inheritance ,Transcription, Genetic ,Organogenesis ,Type 2 diabetes ,Medical and Health Sciences ,0302 clinical medicine ,2.1 Biological and endogenous factors ,Aetiology ,Induced pluripotent stem cell ,Genetics ,0303 health sciences ,Fetal Growth Retardation ,Diabetes ,Gallbladder ,Cell Differentiation ,General Medicine ,3. Good health ,Hepatocyte Nuclear Factor 6 ,medicine.anatomical_structure ,Homeobox Protein Nkx-2.2 ,Pancreas ,Transcription ,General Economics, Econometrics and Finance ,Type 2 ,Pluripotent Stem Cells ,Immunology ,030209 endocrinology & metabolism ,Biology ,Autoimmune Disease ,General Biochemistry, Genetics and Molecular Biology ,Article ,Congenital Abnormalities ,03 medical and health sciences ,Directed differentiation ,Genetic ,Clinical Research ,Diabetes mellitus ,Diabetes Mellitus ,medicine ,Humans ,Epigenetics ,Progenitor cell ,Metabolic and endocrine ,030304 developmental biology ,Homeodomain Proteins ,Infant, Newborn ,Infant ,Pancreatic Diseases ,Newborn ,Stem Cell Research ,medicine.disease ,Diabetes Mellitus, Type 2 - Abstract
Genes involved in distinct diabetes types suggest shared disease mechanisms. Here we show that One Cut Homeobox 1 (ONECUT1) mutations cause monogenic recessive syndromic diabetes in two unrelated patients, characterized by intrauterine growth retardation, pancreas hypoplasia and gallbladder agenesis/hypoplasia, and early-onset diabetes in heterozygous relatives. Heterozygous carriers of rare coding variants of ONECUT1 define a distinctive subgroup of diabetic patients with early-onset, nonautoimmune diabetes, who respond well to diabetes treatment. In addition, common regulatory ONECUT1 variants are associated with multifactorial type 2 diabetes. Directed differentiation of human pluripotent stem cells revealed that loss of ONECUT1 impairs pancreatic progenitor formation and a subsequent endocrine program. Loss of ONECUT1 altered transcription factor binding and enhancer activity and NKX2.2/NKX6.1 expression in pancreatic progenitor cells. Collectively, we demonstrate that ONECUT1 controls a transcriptional and epigenetic machinery regulating endocrine development, involved in a spectrum of diabetes, encompassing monogenic (recessive and dominant) as well as multifactorial inheritance. Our findings highlight the broad contribution of ONECUT1 in diabetes pathogenesis, marking an important step toward precision diabetes medicine.
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- 2020
24. Pancreatic cancer-derived organoids – a disease modeling tool to predict drug response
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Reinhild Rösler, Lucas-Alexander Schulte, Johann Gout, Heike Wiese, Ralf Marienfeld, Patrick C. Hermann, Thomas Seufferlein, Martin Müller, Alica K Beutel, Thilo Hackert, André Lechel, Frank Arnold, Sebastian Wiese, Thomas J. Ettrich, Thomas F. E. Barth, Pierre Olivier Frappart, M. Svinarenko, Alexander Kleger, Bruno Sainz, Markus Breunig, Lukas Perkhofer, Karolin Walter, Mareen Morawe, German Cancer Aid, German Research Foundation, Research and Art Baden-Württemberg, Agence Nationale de la Recherche (France), Ulm University, The Hector Foundation, Ministerio de Economía y Competitividad (España), and Fundación Científica Asociación Española Contra el Cáncer
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Adult ,Male ,Pancreatic ductal adenocarcinoma ,endocrine system diseases ,Cell Survival ,Biopsy ,Cell Culture Techniques ,Antineoplastic Agents ,Disease ,Proof of Concept Study ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Drug response prediction ,Pancreatic cancer ,medicine ,Organoid ,Drug response ,Animals ,Humans ,Pancreatic carcinoma ,skin and connective tissue diseases ,Pancreas ,business.industry ,Gastroenterology ,food and beverages ,Cancer ,PDAC ,Original Articles ,medicine.disease ,Primary cancer ,Xenograft Model Antitumor Assays ,digestive system diseases ,Pancreatic Neoplasms ,Organoids ,Oncology ,030220 oncology & carcinogenesis ,Cancer research ,Feasibility Studies ,030211 gastroenterology & hepatology ,Female ,Drug Screening Assays, Antitumor ,business ,Corrigendum ,Carcinoma, Pancreatic Ductal - Abstract
[Background]: Organotypic cultures derived from pancreatic ductal adenocarcinoma (PDAC) termed pancreatic ductal cancer organoids (PDOs) recapitulate the primary cancer and can be derived from primary or metastatic biopsies. Although isolation and culture of patient-derived pancreatic organoids were established several years ago, pros and cons for individualized medicine have not been comprehensively investigated to date., [Methods]: We conducted a feasibility study, systematically comparing head-to-head patient-derived xenograft tumor (PDX) and PDX-derived organoids by rigorous immunohistochemical and molecular characterization. Subsequently, a drug testing platform was set up and validated in vivo. Patient-derived organoids were investigated as well., [Results]: First, PDOs faithfully recapitulated the morphology and marker protein expression patterns of the PDXs. Second, quantitative proteomes from the PDX as well as from corresponding organoid cultures showed high concordance. Third, genomic alterations, as assessed by array-based comparative genomic hybridization, revealed similar results in both groups. Fourth, we established a small-scale pharmacotyping platform adjusted to operate in parallel considering potential obstacles such as culture conditions, timing, drug dosing, and interpretation of the results. In vitro predictions were successfully validated in an in vivo xenograft trial. Translational proof-of-concept is exemplified in a patient with PDAC receiving palliative chemotherapy., [Conclusion]: Small-scale drug screening in organoids appears to be a feasible, robust and easy-to-handle disease modeling method to allow response predictions in parallel to daily clinical routine. Therefore, our fast and cost-efficient assay is a reasonable approach in a predictive clinical setting., The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Main funding is provided by the German Cancer Aid grant to A. Kleger (111879). Additional funding came from the Deutsche Forschungsgemeinschaft (DFG, K.L. 2544/1-1, and 1-2; GRK 2254/1 to T. Seufferlein), the BIU fund (Böhringer Ingelheim), the NDIMED-Verbund PancChip, and the Else-Kröner-Fresenius Memorial funding to A. Kleger. AK receives also funding from the DFG within the Heisenberg program and from the Baden-Württemberg Foundation via ExPo Chip. This project was also funded by ANR-DFG collaborative research project (ANR-18-CE92-0031, DFG KL 2544/5-1) to CJ and AK and via additional DFG funding KL 2544/6-1, KL 2544/7-1, KL 2544/1-1, and KL 2544/1-2 to AK. L. Perkhofer is funded by Bausteinprogramm of the Ulm University hospital. This work was supported by a project grant for André Lechel (Deutsche Krebshilfe/111264), for Patrick C. Hermann (Max Eder Fellowship 111746, Projektnummer 316249678 – SFB 1279, and Hector Foundation Cancer Research grant M65.1). Reinhild Rösler and parts of proteomics method development were funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – SFB 1074. Bruno Sainz Jr was funded by a Ramón y Cajal Merit Award from the Ministerio de Economía y Competitividad, Spain and a coordinated grant from the Fundación Asociación Española Contra el Cáncer (AECC).
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- 2020
25. Pancreatic Ductal Organoids React Kras Dependent to the Removal of Tumor Suppressive Roadblocks
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Frank Arnold, Pierre Olivier Frappart, Lukas Perkhofer, Markus Breunig, Thomas Seufferlein, Melanie Engler, Johann Gout, Mareen Morawe, and Alexander Kleger
- Subjects
lcsh:Internal medicine ,endocrine system diseases ,Article Subject ,Effector ,Genetic heterogeneity ,Context (language use) ,Cell Biology ,Biology ,medicine.disease_cause ,In vitro ,digestive system diseases ,In vivo ,Cancer research ,Organoid ,biology.protein ,medicine ,PTEN ,KRAS ,lcsh:RC31-1245 ,Molecular Biology ,Research Article - Abstract
Pancreatic ductal adenocarcinoma (PDAC) is still the Achilles heel in modern oncology, with an increasing incidence accompanied by a persisting high mortality. The developmental process of PDAC is thought to be stepwise via precursor lesions and sequential accumulation of mutations. Thereby, current sequencing studies recapitulate this genetic heterogeneity in PDAC and show besides a handful of driver mutations (KRAS, TP53) a plethora of passenger mutations that allow to define subtypes. However, modeling the mutations of interest and their effects is still challenging. Interestingly, organoids have the potential to recapitulate in vitro, the in vivo characteristics of the tissue they originate from. Here, we could establish and develop tools allowing us to isolate, culture, and genetically modify ductal mouse organoids. Transferred to known effectors in the IPMN-PDAC sequence, we could reveal significantly increased proliferative and self-renewal capacities for PTEN and RNF43 deficiency in the context of oncogenic KRASG12D in mouse pancreatic organoids. Overall, we were able to obtain promising data centering ductal organoids in the focus of future PDAC research.
- Published
- 2019
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26. Reprogramming to pluripotency does not require transition through a primitive streak-like state
- Author
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Anett Illing, Jelena Tosic, Stefan Liebau, Sebastian J. Arnold, Thomas Seufferlein, Stefanie Raab, Markus Breunig, Anna Möller, Alexander Kleger, Leonhard Linta, Moritz Klingenstein, and Georg Kuales
- Subjects
0301 basic medicine ,Pluripotent Stem Cells ,Primitive Streak ,Somatic cell ,lcsh:Medicine ,Eomesodermin ,Biology ,Article ,Mesoderm ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Ectoderm ,Animals ,Humans ,lcsh:Science ,Induced pluripotent stem cell ,Transcription factor ,Loss function ,Multidisciplinary ,Primitive streak ,lcsh:R ,Embryogenesis ,Fibroblasts ,Cellular Reprogramming ,Cell biology ,030104 developmental biology ,embryonic structures ,lcsh:Q ,T-Box Domain Proteins ,Reprogramming ,030217 neurology & neurosurgery - Abstract
Pluripotency can be induced in vitro from adult somatic mammalian cells by enforced expression of defined transcription factors regulating and initiating the pluripotency network. Despite the substantial advances over the last decade to improve the efficiency of direct reprogramming, exact mechanisms underlying the conversion into the pluripotent stem cell state are still vaguely understood. Several studies suggested that induced pluripotency follows reversed embryonic development. For somatic cells of mesodermal and endodermal origin that would require the transition through a Primitive streak-like state, which would necessarily require an Eomesodermin (Eomes) expressing intermediate. We analyzed reprogramming in human and mouse cells of mesodermal as well as ectodermal origin by thorough marker gene analyses in combination with genetic reporters, conditional loss of function and stable fate-labeling for the broad primitive streak marker Eomes. We unambiguously demonstrate that induced pluripotency is not dependent on a transient primitive streak-like stage and thus does not represent reversal of mesendodermal development in vivo.
- Published
- 2017
27. Human pluripotent stem cell-derived acinar/ductal organoids generate human pancreas upon orthotopic transplantation and allow disease modelling
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Susanne Renz, Marianne Stockmann, Stefan Liebau, André Lechel, Chao-Chung Kuo, Tim Eiseler, Thomas Seufferlein, Michael S. D. Kormann, Meike Hohwieler, Michael Leichsenring, Martin Müller, Martin Zenke, Markus Breunig, Ivan G. Costa, Martin Zenker, Lukas Perkhofer, Anett Illing, Qiong Lin, Patrick C. Hermann, Matthias Sendler, Martin Wagner, Bruno Sainz, Julia Mayerle, Tobias Mayer, Jonas Rosendahl, Justin S. Antony, Susanne Kleiderman, Alexander Kleger, European Commission, RWTH Aachen University, Ministry of Science, Research and Art Baden-Württemberg, Ulm University, Deutsches Krebsforschungszentrum, Fritz Thyssen Foundation, Boehringer Ingelheim Fonds, German Research Foundation, UAM. Departamento de Bioquímica, and Instituto de Investigaciones Biomédicas 'Alberto Sols' (IIBM)
- Subjects
0301 basic medicine ,Pluripotent Stem Cells ,Pathology ,medicine.medical_specialty ,Pancreatic disease ,Cystic Fibrosis ,Ductal cells ,Medicina ,Genetic enhancement ,Cystic Fibrosis Transmembrane Conductance Regulator ,Stem cells ,Acinar Cells ,Biology ,Cystic fibrosis ,03 medical and health sciences ,Mice ,Organoid ,medicine ,Animals ,Humans ,RNA, Messenger ,Induced pluripotent stem cell ,Pancreas ,Gene Expression Profiling ,Gastroenterology ,Pancreatic Ducts ,Genetic Therapy ,medicine.disease ,Cystic fibrosis transmembrane conductance regulator ,Pancreatic Neoplasms ,Organoids ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Phenotype ,biology.protein ,Cancer research ,Stem cell - Abstract
[Objective]: The generation of acinar and ductal cells from human pluripotent stem cells (PSCs) is a poorly studied process, although various diseases arise from this compartment. [Design]: We designed a straightforward approach to direct human PSCs towards pancreatic organoids resembling acinar and ductal progeny. [Results]: Extensive phenotyping of the organoids not only shows the appropriate marker profile but also ultrastructural, global gene expression and functional hallmarks of the human pancreas in the dish. Upon orthotopic transplantation into immunodeficient mice, these organoids form normal pancreatic ducts and acinar tissue resembling fetal human pancreas without evidence of tumour formation or transformation. Finally, we implemented this unique phenotyping tool as a model to study the pancreatic facets of cystic fibrosis (CF). For the first time, we provide evidence that in vitro, but also in our xenograft transplantation assay, pancreatic commitment occurs generally unhindered in CF. Importantly, cystic fibrosis transmembrane conductance regulator (CFTR) activation in mutated pancreatic organoids not only mirrors the CF phenotype in functional assays but also at a global expression level. We also conducted a scalable proof-of-concept screen in CF pancreatic organoids using a set of CFTR correctors and activators, and established an mRNA-mediated gene therapy approach in CF organoids. [Conclusions]: Taken together, our platform provides novel opportunities to model pancreatic disease and development, screen for disease-rescuing agents and to test therapeutic procedures., This study was funded by the Deutsche Forschungsgemeinschaft (DFG, K.L. 2544/1-1 and 1-2), the Forschungskern SyStaR to AK, BIU (Böhringer Ingelheim Ulm to AK), the Fritz-Thyssen Foundation (Az. 10.15.2.040), the German Cancer Aid (111879) and the Else-Kröner-Fresenius-Stiftung (2011_A200). AK is indebted to the Baden-Württemberg Stiftung for the financial support of this research project by the Eliteprogramme for Postdocs. AK is also an Else-Kröner-Fresenius Memorial Fellow. LP is supported by a research fellowship of the Else-Kröner-Fresenius Stiftung. MH was supported by the International Graduate School in Molecular Medicine and the Bausteinprogramme (L.SBN. 110), Ulm University. MM is supported by a grant of Ulm University (Baustein for Senior Clinician Scientists). IGC is funded by the Interdisciplinary Center for Clinical Research (IZKF Aachen) and Start Program, RWTH Aachen University Medical School, Aachen, Germany. AK was supported by an UEG Top Abstract Prize awarded at the United European Gastroenterology Week 2015.
- Published
- 2017
28. The role of myosin 1c and myosin 1b for surfactant exocytosis
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Hans-Joachim Knölker, Pika Miklavc, Markus Breunig, René Martin, and Nadine Kittelberger
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Male ,0301 basic medicine ,Bodily Secretions ,Myosin 1 ,Myosin light-chain kinase ,macromolecular substances ,Biology ,Microfilament ,Membrane Fusion ,Exocytosis ,Rats, Sprague-Dawley ,Myosin Type I ,03 medical and health sciences ,Myosin ,Animals ,Cells, Cultured ,Surfactant secretion ,Secretory Vesicles ,Actin remodeling ,Pulmonary Surfactants ,Cell Biology ,Kiss-and-run fusion ,Actin cytoskeleton ,Secretory Vesicle ,Rats ,Cell biology ,Actin Cytoskeleton ,030104 developmental biology ,Alveolar Epithelial Cells ,Research Article - Abstract
Actin and actin-associated proteins have a pivotal effect on regulated exocytosis in secretory cells and influence pre-fusion as well as post-fusion stages of exocytosis. Actin polymerization on secretory granules during the post-fusion phase (formation of an actin coat) is especially important in cells with large secretory vesicles or poorly soluble secretions. Alveolar type II (ATII) cells secrete hydrophobic lipo-protein surfactant, which does not easily diffuse from fused vesicles. Previous work showed that compression of actin coat is necessary for surfactant extrusion. Here, we investigate the role of class 1 myosins as possible linkers between actin and membranes during exocytosis. Live-cell microscopy showed translocation of fluorescently labeled myosin 1b and myosin 1c to the secretory vesicle membrane after fusion. Myosin 1c translocation was dependent on its pleckstrin homology domain. Expression of myosin 1b and myosin 1c constructs influenced vesicle compression rate, whereas only the inhibition of myosin 1c reduced exocytosis. These findings suggest that class 1 myosins participate in several stages of ATII cell exocytosis and link actin coats to the secretory vesicle membrane to influence vesicle compression., Summary: Myosin 1b and 1c localize to fused secretory vesicles and influence the compression of the actin coat during exocytosis.
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- 2016
29. PPDPF impacts pancreatic progenitor cell formation derived from human pluripotent stem cell
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Alexander Kleger, J Glöckner, Markus Breunig, Thomas Seufferlein, Meike Hohwieler, and Stefan Liebau
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Gastroenterology ,Pancreatic progenitor cell ,Biology ,Induced pluripotent stem cell ,Cell biology - Published
- 2018
30. A coherent roadmap to generate either pancreatic acinar or duct-like cells from human pluripotent stem cells challenges pancreatic cancer biology
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J Merkle, Alexander Kleger, Markus Breunig, Pierre Olivier Frappart, Maike Hohwieler, Thomas Seufferlein, and Sandra Heller
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medicine.anatomical_structure ,Hepatology ,Endocrinology, Diabetes and Metabolism ,Pancreatic cancer ,Gastroenterology ,medicine ,Cancer research ,Biology ,medicine.disease ,Induced pluripotent stem cell ,Duct (anatomy) - Published
- 2018
31. Normalization of TanDEM-X DSM Data in Urban Environments With Morphological Filters
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Markus Breunig, Hannes Taubenböck, Andreas Felbier, Michael Wurm, and Christian Geiss
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Normalization (statistics) ,Pixel ,Structuring element ,Computer science ,business.industry ,Terrain ,Digital surfacemodels (DSM) ,Filter (signal processing) ,digital terain models (DTM) ,Interferometry ,Region growing ,General Earth and Planetary Sciences ,Computer vision ,Artificial intelligence ,Georisiken und zivile Sicherheit ,Electrical and Electronic Engineering ,morphological filters ,TanDEM-X ,business ,Image resolution ,Landoberfläche ,Interpolation - Abstract
The TanDEM-X mission (TDM) is a spaceborne Radar interferometer which delivers a global digital surface model (DSM) with an unprecedented spatial resolution. This allows resolving objects above ground such as buildings. Extracting and characterizing those objects in an automated manner represents a challenging problem but opens simultaneously a broad range of large-area applications. In this paper, we discuss and evaluate the suitability of morphological filters (MFs) for the derivation of normalized DSMs from the TDM in complex urban Environments and introduce a novel region-growing-based progressive MF procedure. This approach is jointly proposed and can be combined with a postclassification processing scheme to specifically allow for a viable reconstruction of urban morphology in a challenging terrain. The filter approach comprises a multistep procedure using concepts of morphological image filtering, region growing, and interpolation techniques. Therefore, it extends the idea of progressive MFs. The latter aim to identify nonground pixels in the DSM by gradually increasing the size of a structuring element and applying iteratively an elevation difference threshold. After the identification of initial nonground pixels, here, potential nonground pixels are identified within each iteration, and their similarity with respect to neighboring nonground pixels is assessed. Pixels are finally labeled as nonground if a constraint is fulfilled. The postclassification processing scheme adapts techniques of object-based image analyses to further refine regions of classified nonground pixels. Digital terrain models are subsequently generated by interpolating between identified ground pixels. Experimental results are obtained for settlement areas that cover large parts of the cities of Izmir (Turkey) and Wuppertal (Germany). They confirm the capability of the proposed approaches for a reduction of omission errors compared to basic MF-based methods when classifying ground pixels, which is favorable in a mountainous Terrain with steep slopes.
- Published
- 2015
32. Validation of the absolute height accuracy of TanDEM-X DEM for moderate terrain
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Anna Wendleder, Martin Huber, Birgit Wessel, Susanne Wagenbrenner, Astrid Gruber, Achim Roth, and Markus Breunig
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validation ,accuracy ,business.industry ,GPS ,TanDEM-X DEM ,Terrain ,Shuttle Radar Topography Mission ,Geodesy ,Data acquisition ,Global Positioning System ,absolute height error ,business ,Digital elevation model ,Scale (map) ,ICESat ,Landoberfläche ,Geology ,Remote sensing - Abstract
In September 2013 the production of TanDEM-X digital elevation model (DEM) started. As the data acquisition for difficult terrain lasted until April 2014, final DEM production started for flat to moderate terrain regions where two final coverages surfice. This paper focuses on a first validation of moderate terrain to prove the absolute height accuracy. In a detailed comparison three DEM tiles from different continents are chosen to validate the TanDEM-X DEM by computing differences to GPS tracks, ICESat validation points, and SRTM. On a global scale all TanDEM-X DEMs produced so far are compared with ICESat and GPS tracks. Both validations presented here for the first time indicate that the absolute height error for moderate terrain for TanDEM-X is below 2m and therefore much better than the specified 10m/LE90.
- Published
- 2014
33. The approach for combining dem acquisitions for the TanDEM-X dem mosaic
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Birgit Wessel, Astrid Gruber, Susanne Wagenbrenner, Markus Breunig, and Martin Huber
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Synthetic aperture radar ,Interferometry ,Computer science ,Radar imaging ,Interferometric synthetic aperture radar ,Contrast (statistics) ,Terrain ,Noise (video) ,Digital elevation model ,Remote sensing - Abstract
For the global TanDEM-X DEM the whole world will be acquired by at least two coverages. Thereby on the one hand phase unwrapping errors are reduced by applying the dual-baseline method and on the other hand a low noise level is ensured even for difficult areas like forests and steep terrain. During DEM mosaicking, the single interferometric DEMs are merged together. This paper focuses on the combination of heights in overlapping areas with significant height differences. The challenge here is to choose the most reliable height value. The improvement applying this strategy in contrast to simple averaging and the general benefit of using more than one acquisition is shown by means of some example mosaics.
- Published
- 2013
34. TanDEM-X Water Indication Mask: Generation and First Evaluation Results
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Susanne Wagenbrenner, Birgit Wessel, Achim Roth, Markus Breunig, Klaus Martin, and Anna Wendleder
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Atmospheric Science ,Computer science ,QC801-809 ,Geophysics. Cosmic physics ,Process (computing) ,Elevation ,Image processing ,water body detection ,coherence ,DEM editing ,Data set ,Ocean engineering ,Interferometry ,Amplitude ,Computers in Earth Sciences ,TanDEM-X ,Digital elevation model ,TC1501-1800 ,Landoberfläche ,Coherence (physics) ,Remote sensing ,amplitude - Abstract
The German SAR interferometry mission TanDEM-X performed on two TerraSAR-X satellites flying in close formation will provide a global Digital Elevation Model (DEM). A by-product is so-called the Water Indication Mask (WAM). The purpose of this supplementary information layer is to support the DEM editing process. Water surfaces usually show lower coherence in an interferometric data set due to temporal de-correlation and low backscattering. Consequently the corresponding elevation values derived from the interferogram are random and produce a virtual relief. This paper introduces the operational water body detection workflow that synergistically evaluates amplitude and coherence information. The presented results of two test sites reveal that the methodology is globally applicable, classifications are highly accurate and the algorithm is appropriate for operational image processing. The water body detection consists of two steps: the Water Body Detection (WBD) derived of one single DEM scene and the mosaicking of multiple WBD to a single Water Indication Mask (WAM). The fusion strategy for the final TanDEM-X WAM considers all WBD acquired at different times in two global coverages and bases on a fusion by union containing the results of the amplitude and the coherence.
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- 2012
35. Identification and characterization of urban structures using VHR SAR data
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Hannes Taubenböck, Stefan Dech, Achim Roth, Wieke Heldens, Andreas Felbier, Martin Schmidt, Thomas Esch, Christian Riegler, and Markus Breunig
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Building management system ,Synthetic aperture radar ,Urban planning ,Urbanization ,Radar imaging ,Human settlement ,Regional planning ,Environmental science ,Satellite system ,Remote sensing - Abstract
The global process of urbanization is associated with various ecological, social and economic changes in both the built-up area and the adjacent natural or cultivated landscape. To manage the effects and impacts of this development, effective urban and regional planning requires accurate and up to date information on the urban dynamics. This paper introduces a methodology to automatically detect human settlements and then further characterize the identified built-up areas in terms of the building density based on VHR SAR data. The SAR imagery is acquired by the German satellite system TerraSAR-X. Regarding the delineation of the built-up area in the region of Munich we achieved an overall accuracy of 94 % and a Kappa of 0.86. The estimation of building density showed a coefficient of determination (r2) of up to 0.74. The mean absolute error of the modeled building densities was 5 %.
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- 2011
36. Production Chain towards First Calibrated and Mosaicked TanDEM-X DEMs
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Markus Breunig, Birgit Wessel, Martin Huber, Achim Roth, Astrid Gruber, Anna Wendleder, Detlev Kosmann, and Ursula Marschalk
- Subjects
Tandem ,Phase (waves) ,TanDEM-X DEM ,mosaicking ,Residual ,calibration ,Azimuth ,Interferometry ,Product (mathematics) ,Calibration ,water mask ,Environmental science ,Digital elevation model ,Remote sensing - Abstract
The main product of the TanDEM-X mission is an interferometric DEM product that is finally calibrated due to residual systematic offsets and tilts and where different, generally two coverages, are mosaicked. Above this, a water mask is provided to support later editing of rough water areas. In this presentation the commissioning phase work to set the DEM production chain into operation is described and the first commissioning phase products are shown.
- Published
- 2011
37. Water body detection from TanDEM-X data: concept and first evaluation of an accurate water indication mask
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Birgit Wessel, Achim Roth, Anna Wendleder, Markus Breunig, and K. Martin
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Synthetic aperture radar ,Tandem ,Computer science ,business.industry ,water ,detection ,TanDEM-X DEM ,Water body ,extraction ,Coherence (signal processing) ,Computer vision ,Artificial intelligence ,business ,Digital elevation model ,Landoberfläche ,Remote sensing - Abstract
Additionally to the main product of the TanDEM-X mission - the global Digital Elevation Model (DEM) - a global water body mask will be produced. The main goal of this water mask is to deliver an information layer to support a subsequent DEM editing process. It is derived from the SAR amplitude and the single pass coherence. In this paper, the concept of the global water body detection is explained and a first evaluation of the single coverage water body detection is presented.
- Published
- 2011
38. Validation of tie-point concepts by the DEM adjustment approach of TanDEM-X
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Anna Wendleder, Birgit Wessel, Martin Huber, Astrid Gruber, and Markus Breunig
- Subjects
Data set ,Synthetic aperture radar ,Noise measurement ,Computer science ,business.industry ,Noise (signal processing) ,Calibration (statistics) ,Point (geometry) ,Computer vision ,Artificial intelligence ,business ,Algorithm - Abstract
The aimed accuracies for the final TanDEM-X DEM of 10m absolute and 2m relative height error will be ensured by calibration data. One crucial data set for the relative accuracy is tie-points that connect adjacent DEM acquisitions in the approximately 4km-overlap-area with each other. In this paper an improved concept for tie-point candidates is presented that is based on averaging a larger region instead of comparing single points. This concept should be more robust against noise. It is validated by applying the DEM calibration on a simulated test area, as real TanDEM-X data was not yet available. Also, the DEM calibration will be validated for the first time on a larger “real” test site by applying the TanDEM-X processing scenario.
- Published
- 2010
39. Changing urbanity in Istanbul
- Author
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Michael Wurm, Achim Roth, Markus Breunig, and Hannes Taubenböck
- Subjects
Suburbanization ,Megacity ,Geography ,Urban planning ,Urbanization ,Urbanity ,Urban studies ,Urban sprawl ,Social studies ,Environmental planning ,Remote sensing - Abstract
The current process of megacity development and urban sprawl are unique in human history. More and more so-called megacities with more than 10 million inhabitants are evolving throughout the world. The presented study is focusing on the earthquake-prone megacity Istanbul officially counting 12 million inhabitants in 2007. During the past decades, the megacity has undergone an enormous suburbanization into its outskirts. Recent urban developments, however, seem to indicate changing housing trends respectively types of urbanization in Istanbul. In our study we focus on a multi-temporal and multisensoral analysis using Landsat and TerraSAR-X data. By implementing an object-oriented classification approach settlement masks for 1975, 1987, 2000, and 2008 have been created. Furthermore, post-classification change detection is displaying medium and large scale urban developments of the megacity for the past decades. The results are conforming to current social studies focusing on urbanity and lifestyle: Istanbul is facing new types and factors of urban development. The study demonstrates both the synergistic usage of multi-temporal and multi-sensoral remotely sensed data. Additionally, the synergistic potential of remote sensing and applied urban studies to work out useful information for urban planners is presented.
- Published
- 2009
40. SARS-CoV-2 infects and replicates in cells of the human endocrine and exocrine pancreas
- Author
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Janis A. Müller, Ivan G. Costa, Caterina Prelli Bozzo, Albrecht Stenzinger, Alexander Kleger, Thomas Seufferlein, Michael Schuster, Rüdiger Groß, Lennart Koepke, Uta Merle, Martin Wagner, Jana Krüger, Sandra Heller, Steffen Stenger, Carina Conzelmann, Manfred Frick, Giorgio Fois, Julia Gehrmann, Thomas F. E. Barth, Tim Eiseler, Tatjana Weil, Joanne van Vuuren, Konstantin M. J. Sparrer, Johannes Steinhart, Patrick E. MacDonald, Heiko Lickert, Lynn Peters, Frank Kirchhoff, Clarissa Read, Isabel M Wessbecher, Paul Walther, Markus Breunig, Beate Grüner, Jan Münch, and Stefan Liebau
- Subjects
Male ,Endocrinology, Diabetes and Metabolism ,viruses ,030209 endocrinology & metabolism ,Biology ,Virus Replication ,03 medical and health sciences ,Islets of Langerhans ,0302 clinical medicine ,In vivo ,Viral entry ,Physiology (medical) ,Diabetes mellitus ,Internal Medicine ,medicine ,Diabetes Mellitus ,Endocrine system ,Humans ,Cells, Cultured ,030304 developmental biology ,Aged ,Aged, 80 and over ,0303 health sciences ,SARS-CoV-2 ,fungi ,Serine Endopeptidases ,Diabetes ,COVID-19 ,Pancreatic Diseases ,Cell Biology ,Virus Internalization ,medicine.disease ,Research Highlight ,Pancreas, Exocrine ,3. Good health ,medicine.anatomical_structure ,Viral replication ,Immunology ,Female ,Angiotensin-Converting Enzyme 2 ,Pancreas ,Ex vivo ,Homeostasis - Abstract
Infection-related diabetes can arise as a result of virus-associated β-cell destruction. Clinical data suggest that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing the coronavirus disease 2019 (COVID-19), impairs glucose homoeostasis, but experimental evidence that SARS-CoV-2 can infect pancreatic tissue has been lacking. In the present study, we show that SARS-CoV-2 infects cells of the human exocrine and endocrine pancreas ex vivo and in vivo. We demonstrate that human β-cells express viral entry proteins, and SARS-CoV-2 infects and replicates in cultured human islets. Infection is associated with morphological, transcriptional and functional changes, including reduced numbers of insulin-secretory granules in β-cells and impaired glucose-stimulated insulin secretion. In COVID-19 full-body postmortem examinations, we detected SARS-CoV-2 nucleocapsid protein in pancreatic exocrine cells, and in cells that stain positive for the β-cell marker NKX6.1 and are in close proximity to the islets of Langerhans in all four patients investigated. Our data identify the human pancreas as a target of SARS-CoV-2 infection and suggest that β-cell infection could contribute to the metabolic dysregulation observed in patients with COVID-19.
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- View/download PDF
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