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Katiyar P, Schwenck J, Frauenfeld L, Divine MR, Agrawal V, Kohlhofer U, Gatidis S, Kontermann R, Königsrainer A, Quintanilla-Martinez L, la Fougère C, Schölkopf B, Pichler BJ, Disselhorst JA. Quantification of intratumoural heterogeneity in mice and patients via machine-learning models trained on PET-MRI data. Nat Biomed Eng 2023; 7:1014-1027. [PMID: 37277483 DOI: 10.1038/s41551-023-01047-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 04/26/2023] [Indexed: 06/07/2023]
Abstract
In oncology, intratumoural heterogeneity is closely linked with the efficacy of therapy, and can be partially characterized via tumour biopsies. Here we show that intratumoural heterogeneity can be characterized spatially via phenotype-specific, multi-view learning classifiers trained with data from dynamic positron emission tomography (PET) and multiparametric magnetic resonance imaging (MRI). Classifiers trained with PET-MRI data from mice with subcutaneous colon cancer quantified phenotypic changes resulting from an apoptosis-inducing targeted therapeutic and provided biologically relevant probability maps of tumour-tissue subtypes. When applied to retrospective PET-MRI data of patients with liver metastases from colorectal cancer, the trained classifiers characterized intratumoural tissue subregions in agreement with tumour histology. The spatial characterization of intratumoural heterogeneity in mice and patients via multimodal, multiparametric imaging aided by machine-learning may facilitate applications in precision oncology.
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Affiliation(s)
- Prateek Katiyar
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
- Max Planck Institute for Intelligent Systems, Tübingen, Germany
| | - Johannes Schwenck
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
- Cluster of Excellence iFIT (EXC 2180) 'Image Guided and Functionally Instructed Tumor Therapies', Eberhard Karls University Tübingen, Tübingen, Germany
- Department of Nuclear Medicine and Clinical Molecular Imaging, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Leonie Frauenfeld
- Institute of Pathology and Neuropathology, Eberhard Karls University Tübingen and Comprehensive Cancer Center, University Hospital Tübingen, Tübingen, Germany
| | - Mathew R Divine
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Vaibhav Agrawal
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
- Max Planck Institute for Intelligent Systems, Tübingen, Germany
| | - Ursula Kohlhofer
- Institute of Pathology and Neuropathology, Eberhard Karls University Tübingen and Comprehensive Cancer Center, University Hospital Tübingen, Tübingen, Germany
| | - Sergios Gatidis
- Cluster of Excellence iFIT (EXC 2180) 'Image Guided and Functionally Instructed Tumor Therapies', Eberhard Karls University Tübingen, Tübingen, Germany
- Department of Radiology, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Roland Kontermann
- Institute of Cell Biology and Immunology, SRCSB, University of Stuttgart, Stuttgart, Germany
| | - Alfred Königsrainer
- Cluster of Excellence iFIT (EXC 2180) 'Image Guided and Functionally Instructed Tumor Therapies', Eberhard Karls University Tübingen, Tübingen, Germany
- Department of General, Visceral and Transplant Surgery, University Hospital Tübingen, Tübingen, Germany
| | - Leticia Quintanilla-Martinez
- Cluster of Excellence iFIT (EXC 2180) 'Image Guided and Functionally Instructed Tumor Therapies', Eberhard Karls University Tübingen, Tübingen, Germany
- Institute of Pathology and Neuropathology, Eberhard Karls University Tübingen and Comprehensive Cancer Center, University Hospital Tübingen, Tübingen, Germany
| | - Christian la Fougère
- Cluster of Excellence iFIT (EXC 2180) 'Image Guided and Functionally Instructed Tumor Therapies', Eberhard Karls University Tübingen, Tübingen, Germany
- Department of Nuclear Medicine and Clinical Molecular Imaging, Eberhard Karls University Tübingen, Tübingen, Germany
- German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Bernhard Schölkopf
- Max Planck Institute for Intelligent Systems, Tübingen, Germany
- Cluster of Excellence iFIT (EXC 2180) 'Image Guided and Functionally Instructed Tumor Therapies', Eberhard Karls University Tübingen, Tübingen, Germany
| | - Bernd J Pichler
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany.
- Cluster of Excellence iFIT (EXC 2180) 'Image Guided and Functionally Instructed Tumor Therapies', Eberhard Karls University Tübingen, Tübingen, Germany.
- German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, Germany.
| | - Jonathan A Disselhorst
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
- Cluster of Excellence iFIT (EXC 2180) 'Image Guided and Functionally Instructed Tumor Therapies', Eberhard Karls University Tübingen, Tübingen, Germany
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2
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Hartung F, Krüwel T, Shi X, Pfizenmaier K, Kontermann R, Chames P, Alves F, Pardo LA. A Novel Anti-Kv10.1 Nanobody Fused to Single-Chain TRAIL Enhances Apoptosis Induction in Cancer Cells. Front Pharmacol 2020; 11:686. [PMID: 32528281 PMCID: PMC7246340 DOI: 10.3389/fphar.2020.00686] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 04/27/2020] [Indexed: 01/11/2023] Open
Abstract
Antibody-based therapies hold promise for a safe and efficient treatment of cancer. The identification of target tumor cells through a specific antigen enriched on their surface and the subsequent delivery of the therapeutic agent only to those cells requires, besides the efficacy of the therapeutic agent itself, the identification of an antigen enriched on the surface of tumor cells, the generation of high affinity antibodies against that antigen. We have generated single-domain antibodies (nanobodies) against the voltage-gated potassium channel Kv10.1, which outside of the brain is detectable almost exclusively in tumor cells. The nanobody with highest affinity was fused to an improved form of the tumor necrosis factor-related apoptosis inducing ligand TRAIL, to target this cytokine to the surface of tumor cells. The resulting construct, VHH-D9-scTRAIL, shows rapid and strong apoptosis induction in different tumor models in cell culture. The construct combines two sources of specificity, the expression of the antigen restricted to tumor cells and the tumor selectivity of TRAIL. Such specificity combined with the high affinity obtained through nanobodies make the novel agent a promising concept for cancer therapy.
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Affiliation(s)
- Franziska Hartung
- Oncophysiology Group, Max Planck, Institute of Experimental Medicine, Göttingen, Germany
| | - Thomas Krüwel
- Institute of Diagnostic and Interventional Radiology, University Medical Center Göttingen, Göttingen, Germany
| | - Xiaoyi Shi
- Oncophysiology Group, Max Planck, Institute of Experimental Medicine, Göttingen, Germany
| | - Klaus Pfizenmaier
- Institut für Zellbiologie und Immunologie, Universität Stuttgart, Stuttgart, Germany
| | - Roland Kontermann
- Institut für Zellbiologie und Immunologie, Universität Stuttgart, Stuttgart, Germany
| | - Patrick Chames
- Aix Marseille Univ, CNRS, Inserm, Institut Paoli-Calmettes, CRCM, Marseille, France
| | - Frauke Alves
- Institute of Diagnostic and Interventional Radiology, University Medical Center Göttingen, Göttingen, Germany.,Translational Molecular Imaging Group, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Luis A Pardo
- Oncophysiology Group, Max Planck, Institute of Experimental Medicine, Göttingen, Germany
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3
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Vetma V, Guttà C, Peters N, Praetorius C, Hutt M, Seifert O, Meier F, Kontermann R, Kulms D, Rehm M. Convergence of pathway analysis and pattern recognition predicts sensitization to latest generation TRAIL therapeutics by IAP antagonism. Cell Death Differ 2020; 27:2417-2432. [PMID: 32081986 PMCID: PMC7370234 DOI: 10.1038/s41418-020-0512-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [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] [Received: 03/05/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 12/28/2022] Open
Abstract
Second generation TRAIL-based therapeutics, combined with sensitising co-treatments, have recently entered clinical trials. However, reliable response predictors for optimal patient selection are not yet available. Here, we demonstrate that a novel and translationally relevant hexavalent TRAIL receptor agonist, IZI1551, in combination with Birinapant, a clinically tested IAP antagonist, efficiently induces cell death in various melanoma models, and that responsiveness can be predicted by combining pathway analysis, data-driven modelling and pattern recognition. Across a panel of 16 melanoma cell lines, responsiveness to IZI1551/Birinapant was heterogeneous, with complete resistance and pronounced synergies observed. Expression patterns of TRAIL pathway regulators allowed us to develop a combinatorial marker that predicts potent cell killing with high accuracy. IZI1551/Birinapant responsiveness could be predicted not only for cell lines, but also for 3D tumour cell spheroids and for cells directly isolated from patient melanoma metastases (80–100% prediction accuracies). Mathematical parameter reduction identified 11 proteins crucial to ensure prediction accuracy, with x-linked inhibitor of apoptosis protein (XIAP) and procaspase-3 scoring highest, and Bcl-2 family members strongly represented. Applied to expression data of a cohort of n = 365 metastatic melanoma patients in a proof of concept in silico trial, the predictor suggested that IZI1551/Birinapant responsiveness could be expected for up to 30% of patient tumours. Overall, response frequencies in melanoma models were very encouraging, and the capability to predict melanoma sensitivity to combinations of latest generation TRAIL-based therapeutics and IAP antagonists can address the need for patient selection strategies in clinical trials based on these novel drugs.
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Affiliation(s)
- Vesna Vetma
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany.,Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Cristiano Guttà
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
| | - Nathalie Peters
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
| | - Christian Praetorius
- Center for Regenerative Therapies, Technical University Dresden, Dresden, Germany.,Skin Cancer Center at the University Cancer Centre, Department of Dermatology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Dresden, Germany
| | - Meike Hutt
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
| | - Oliver Seifert
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
| | - Friedegund Meier
- Skin Cancer Center at the University Cancer Centre, Department of Dermatology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Dresden, Germany.,National Center for Tumor Diseases (NCT), Dresden, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Roland Kontermann
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany.,Stuttgart Research Center Systems Biology, University of Stuttgart, Stuttgart, Germany
| | - Dagmar Kulms
- Center for Regenerative Therapies, Technical University Dresden, Dresden, Germany.,Skin Cancer Center at the University Cancer Centre, Department of Dermatology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Dresden, Germany.,Experimental Dermatology, Department of Dermatology, Technical University Dresden, Dresden, Germany
| | - Markus Rehm
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany. .,Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland. .,Stuttgart Research Center Systems Biology, University of Stuttgart, Stuttgart, Germany. .,Stuttgart Centre for Simulation Science (SC SimTech), University of Stuttgart, Stuttgart, Germany. .,Centre for Systems Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland.
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4
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Fabre M, Ferrer C, Domínguez-Hormaetxe S, Kontermann R, Pfizenmaier K, Seifer O, Vivanco M, Lee SY, López-Casas P, Abbas M, Richter W, Simon L, Hidalgo M. Tumour stroma targeting and modulation by OMTX705 ADC, a novel and potent immunotherapeutic treatment of solid tumours. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz253.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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5
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Puerto-Camacho P, Amaral AT, Lamhamedi-Cherradi SE, Menegaz BA, Castillo-Ecija H, Ordóñez JL, Domínguez S, Jordan-Perez C, Diaz-Martin J, Romero-Pérez L, Lopez-Alvarez M, Civantos-Jubera G, Robles-Frías MJ, Biscuola M, Ferrer C, Mora J, Cuglievan B, Schadler K, Seifert O, Kontermann R, Pfizenmaier K, Simón L, Fabre M, Carcaboso ÁM, Ludwig JA, de Álava E. Preclinical Efficacy of Endoglin-Targeting Antibody-Drug Conjugates for the Treatment of Ewing Sarcoma. Clin Cancer Res 2018; 25:2228-2240. [PMID: 30420447 DOI: 10.1158/1078-0432.ccr-18-0936] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 07/13/2018] [Accepted: 11/06/2018] [Indexed: 12/26/2022]
Abstract
PURPOSE Endoglin (ENG; CD105) is a coreceptor of the TGFβ family that is highly expressed in proliferating endothelial cells. Often coopted by cancer cells, ENG can lead to neo-angiogenesis and vasculogenic mimicry in aggressive malignancies. It exists both as a transmembrane cell surface protein, where it primarily interacts with TGFβ, and as a soluble matricellular protein (sENG) when cleaved by matrix metalloproteinase 14 (MMP14). High ENG expression has been associated with poor prognosis in Ewing sarcoma, an aggressive bone cancer that primarily occurs in adolescents and young adults. However, the therapeutic value of ENG targeting has not been fully explored in this disease. EXPERIMENTAL DESIGN We characterized the expression pattern of transmembrane ENG, sENG, and MMP14 in preclinical and clinical samples. Subsequently, the antineoplastic potential of two novel ENG-targeting monoclonal antibody-drug conjugates (ADC), OMTX503 and OMTX703, which differed only by their drug payload (nigrin-b A chain and cytolysin, respectively), was assessed in cell lines and preclinical animal models of Ewing sarcoma. RESULTS Both ADCs suppressed cell proliferation in proportion to the endogenous levels of ENG observed in vitro. Moreover, the ADCs significantly delayed tumor growth in Ewing sarcoma cell line-derived xenografts and patient-derived xenografts in a dose-dependent manner. CONCLUSIONS Taken together, these studies demonstrate potent preclinical activity of first-in-class anti-ENG ADCs as a nascent strategy to eradicate Ewing sarcoma.
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Affiliation(s)
- Pilar Puerto-Camacho
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | - Ana Teresa Amaral
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | | | - Brian A Menegaz
- Department of Sarcoma Medical Oncology, MD Anderson Cancer Center, Houston, Texas
| | - Helena Castillo-Ecija
- Institut de Recerca Sant Joan de Déu, Pediatric Hematology and Oncology, Hospital Sant Joan de Déu Barcelona, Spain
| | - José Luis Ordóñez
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | | | - Carmen Jordan-Perez
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | - Juan Diaz-Martin
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | - Laura Romero-Pérez
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | - Maria Lopez-Alvarez
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | - Gema Civantos-Jubera
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | - María José Robles-Frías
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | - Michele Biscuola
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain
| | | | - Jaume Mora
- Institut de Recerca Sant Joan de Déu, Pediatric Hematology and Oncology, Hospital Sant Joan de Déu Barcelona, Spain
| | - Branko Cuglievan
- Department of Sarcoma Medical Oncology, MD Anderson Cancer Center, Houston, Texas
| | - Keri Schadler
- Department of Sarcoma Medical Oncology, MD Anderson Cancer Center, Houston, Texas
| | | | | | | | | | | | - Ángel M Carcaboso
- Institut de Recerca Sant Joan de Déu, Pediatric Hematology and Oncology, Hospital Sant Joan de Déu Barcelona, Spain
| | - Joseph A Ludwig
- Department of Sarcoma Medical Oncology, MD Anderson Cancer Center, Houston, Texas.
| | - Enrique de Álava
- Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital/CSIC/University of Sevilla/CIBERONC, Seville, Spain.
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6
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Fabre M, Ferrer C, Dominguez-Hormaetxe S, Kontermann R, Pfizenmaier K, Seifert O, López-Casas P, Abbas M, Richter W, Simon L, Hidalgo M. OMTX705, a powerful stroma-targeting ADC to treat invasive tumors with low response to immunotherapeutic anti-PD-1 treatments. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy288.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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7
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Sapski S, Beha N, Kontermann R, Müller D. Tumor-targeted costimulation with antibody-fusion proteins improves bispecific antibody-mediated immune response in presence of immunosuppressive factors. Oncoimmunology 2017; 6:e1361594. [PMID: 29209565 DOI: 10.1080/2162402x.2017.1361594] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 07/25/2017] [Accepted: 07/26/2017] [Indexed: 10/19/2022] Open
Abstract
Therapeutic strategies aiming for the induction of an effective immune response at the tumor site can be severely hampered by the encounter of an immunosuppressive microenvironment. We investigated here the potential of concerted costimulation by tumor-directed antibody-fusion proteins with B7.1, 4-1BBL and OX40L to enforce bispecific antibody-induced T cell stimulation in presence of recognized immunosuppressive factors including IL-10, TGF-β, indoleamine 2,3-dioxygenase (IDO), PD-L1 and regulatory T cells. The expression and activity of these factors was demonstrated in the HT1080-FAP/PBMC co-culture setting, where individual and combined costimulation were still capable to enhance T cell stimulation, even though the general activation level was reduced. Additional blockade of TGF-ß or PD-1 resulted especially effective in further enhancing the degree of T cell activation. Here, best outcome was achieved by combined costimulation of targeted 4-1BBL and B7.1. Furthermore, their individual impact on the proliferation of naïve, memory and effector CD8+ and CD4+ T cell subsets, suggest the coverage of a comprehensive T cell response. Thus, our costimulatory antibody-fusion proteins show great potential to support T cell activation in adverse conditions dictated by the tumor microenvironment.
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Affiliation(s)
- Sabrina Sapski
- Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, Stuttgart, Germany
| | - Nadine Beha
- Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, Stuttgart, Germany
| | - Roland Kontermann
- Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, Stuttgart, Germany
| | - Dafne Müller
- Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, Stuttgart, Germany
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8
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Lindner R, Moosmann A, Dietrich A, Böttinger H, Kontermann R, Siemann-Herzberg M. Process development of periplasmatically produced single chain fragment variable against epidermal growth factor receptor in Escherichia coli. J Biotechnol 2015; 192 Pt A:136-45. [PMID: 25450642 DOI: 10.1016/j.jbiotec.2014.10.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 09/25/2014] [Accepted: 10/07/2014] [Indexed: 11/17/2022]
Abstract
Prokaryotic production systems have been widely used to manufacture recombinant therapeutic proteins. Economically, the prokaryotic production – especially of small therapeutic molecules – is advantageous compared to eukaryotic production strategies. However, due to the potential endotoxin and host cell protein contamination, the requirements for the purification process are disproportionately higher and therefore more expensive and elaborate to circumvent. For this reason, the goal of this work was to develop and establish a rapid, simple, inexpensive and ‘up-scalable’ production and purification process, using the therapeutic relevant protein anti-EGFR scFv hu225 as model molecule. Configuring high cell density cultivation of Escherichia coli – using the rha-BAD expression system as production platform – a specific product concentration up to 20 mgscFv/gCDW was obtained. By combining freeze-and-thaw, osmotic shock and pH induced host cell protein precipitation, almost 70% of the product was extracted from the biomass. In a novel approach a mixed mode chromatography was implemented as a capturing and desalting step, which allowed the direct application of further ion exchange chromatography steps for purification up to pharmaceutical grade. Thereby, 50% of the produced scFv could be purified within 10 h while maintaining the biological activity.
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9
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Möller Y, Siegemund M, Beyes S, Herr R, Lecis D, Delia D, Kontermann R, Brummer T, Pfizenmaier K, Olayioye MA. EGFR-targeted TRAIL and a Smac mimetic synergize to overcome apoptosis resistance in KRAS mutant colorectal cancer cells. PLoS One 2014; 9:e107165. [PMID: 25198428 PMCID: PMC4157814 DOI: 10.1371/journal.pone.0107165] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 08/04/2014] [Indexed: 11/18/2022] Open
Abstract
TRAIL is a death receptor ligand that induces cell death preferentially in tumor cells. Recombinant soluble TRAIL, however, performs poorly as an anti-cancer therapeutic because oligomerization is required for potent biological activity. We previously generated a diabody format of tumor-targeted TRAIL termed DbαEGFR-scTRAIL, comprising single-stranded TRAIL molecules (scTRAIL) and the variable domains of a humanized variant of the EGFR blocking antibody Cetuximab. Here we define the bioactivity of DbαEGFR-scTRAIL with regard to both EGFR inhibition and TRAIL receptor activation in 3D cultures of Caco-2 colorectal cancer cells, which express wild-type K-Ras. Compared with conventional 2D cultures, Caco-2 cells displayed strongly enhanced sensitivity toward DbαEGFR-scTRAIL in these 3D cultures. We show that the antibody moiety of DbαEGFR-scTRAIL not only efficiently competed with ligand-induced EGFR function, but also determined the apoptotic response by specifically directing DbαEGFR-scTRAIL to EGFR-positive cells. To address how aberrantly activated K-Ras, which leads to Cetuximab resistance, affects DbαEGFR-scTRAIL sensitivity, we generated stable Caco-2tet cells inducibly expressing oncogenic K-RasG12V. In the presence of doxycycline, these cells showed increased resistance to DbαEGFR-scTRAIL, associated with the elevated expression of the anti-apoptotic proteins cIAP2, Bcl-xL and FlipS. Co-treatment of cells with the Smac mimetic SM83 restored the DbαEGFR-scTRAIL-induced apoptotic response. Importantly, this synergy between DbαEGFR-scTRAIL and SM83 also translated to 3D cultures of oncogenic K-Ras expressing HCT-116 and LoVo colorectal cancer cells. Our findings thus support the notion that DbαEGFR-scTRAIL therapy in combination with apoptosis-sensitizing agents may be promising for the treatment of EGFR-positive colorectal cancers, independently of their KRAS status.
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Affiliation(s)
- Yvonne Möller
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
| | - Martin Siegemund
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
| | - Sven Beyes
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
| | - Ricarda Herr
- Institute of Molecular Medicine and Cell Research (IMMZ), Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- Faculty of Biology, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Daniele Lecis
- Department of Experimental Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Domenico Delia
- Department of Experimental Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Roland Kontermann
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
| | - Tilman Brummer
- Institute of Molecular Medicine and Cell Research (IMMZ), Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- Centre for Biological Signalling Studies BIOSS, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Klaus Pfizenmaier
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
| | - Monilola A. Olayioye
- Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart, Germany
- * E-mail:
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10
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Oesterreich B, Lorenz B, Schmitter T, Kontermann R, Zenn M, Zimmermann B, Haake M, Lorenz U, Ohlsen K. Characterization of the biological anti-staphylococcal functionality of hUK-66 IgG1, a humanized monoclonal antibody as substantial component for an immunotherapeutic approach. Hum Vaccin Immunother 2014; 10:926-37. [PMID: 24495867 DOI: 10.4161/hv.27692] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Multi-antigen immunotherapy approaches against Staphylococcus aureus are expected to have the best chance of clinical success when used in combinatorial therapy, potentially incorporating opsonic killing of bacteria and toxin neutralization. We recently reported the development of a murine monoclonal antibody specific for the immunodominant staphylococcal antigen A (IsaA), which showed highly efficient staphylococcal killing in experimental infection models of S. aureus. If IsaA-specific antibodies are to be used as a component of combination therapy in humans, the binding specificity and biological activity of the humanized variant must be preserved. Here, we describe the functional characterization of a humanized monoclonal IgG1 variant designated, hUK-66. The humanized antibody showed comparable binding kinetics to those of its murine parent, and recognized the target antigen IsaA on the surface of clinically relevant S. aureus lineages. Furthermore, hUK-66 enhances the killing of S. aureus in whole blood (a physiological environment) samples from healthy subjects and patients prone to staphylococcal infections such as diabetes and dialysis patients, and patients with generalized artery occlusive disease indicating no interference with already present natural antibodies. Taken together, these data indicate that hUK-66 mediates bacterial killing even in high risk patients and thus, could play a role for immunotherapy strategies to combat severe S. aureus infections.
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Affiliation(s)
- Babett Oesterreich
- Institute for Molecular Infection Biology; University of Wuerzburg; Wuerzburg, Germany
| | - Birgit Lorenz
- Institute for Molecular Infection Biology; University of Wuerzburg; Wuerzburg, Germany
| | - Tim Schmitter
- Institute for Molecular Infection Biology; University of Wuerzburg; Wuerzburg, Germany
| | - Roland Kontermann
- Institute for Cell Biology and Immunology; University of Stuttgart; Stuttgart, Germany
| | | | | | - Markus Haake
- Institute for Molecular Infection Biology; University of Wuerzburg; Wuerzburg, Germany
| | - Udo Lorenz
- Department of General, Visceral, Vascular and Paediatric Surgery; University Clinic of Wuerzburg; Wuerzburg, Germany
| | - Knut Ohlsen
- Institute for Molecular Infection Biology; University of Wuerzburg; Wuerzburg, Germany
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11
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Fischer R, Wajant H, Kontermann R, Pfizenmaier K, Maier O. Astrocyte-specific activation of TNFR2 promotes oligodendrocyte maturation by secretion of leukemia inhibitory factor. Glia 2013; 62:272-83. [PMID: 24310780 DOI: 10.1002/glia.22605] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 11/05/2013] [Accepted: 11/06/2013] [Indexed: 01/06/2023]
Abstract
Tumor necrosis factor (TNF) and its receptors TNFR1 and TNFR2 have pleiotropic effects in neurodegenerative disorders. For example, while TNFR1 mediates neurodegenerative effects in multiple sclerosis, TNFR2 is protective and contributes to remyelination. The exact mode of TNFR2 action, however, is poorly understood. Here, we show that TNFR2-mediated activation of the PI3K-PKB/Akt pathway in primary astrocytes increased the expression of neuroprotective genes, including that encoding the neurotrophic cytokine leukemia inhibitory factor (LIF). To investigate whether intercellular signaling between TNFR2-stimulated astrocytes and oligodendrocytes plays a role in oligodendrocyte maturation, we established an astrocyte-oligodendrocyte coculture model, composed of primary astrocytes from huTNFR2-transgenic (tgE1335) mice and oligodendrocyte progenitor cells (OPCs) from wild-type mice, capable of differentiating into mature myelinating oligodendrocytes. In this model, selective stimulation of human TNFR2 on astrocytes, promoted differentiation of cocultured OPCs to myelin basic protein-positive mature oligodendrocytes. Addition of LIF neutralizing antibodies inhibited oligodendrocyte differentiation, indicating a crucial role of TNFR2-induced astrocyte derived LIF for oligodendrocyte maturation.
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Affiliation(s)
- Roman Fischer
- Institute of Cell Biology and Immunology, University Stuttgart, Stuttgart, Germany
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12
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Wahl K, Siegemund M, Lehner F, Vondran F, Nüssler A, Länger F, Krech T, Kontermann R, Manns MP, Schulze-Osthoff K, Pfizenmaier K, Bantel H. Increased apoptosis induction in hepatocellular carcinoma by a novel tumor-targeted TRAIL fusion protein combined with bortezomib. Hepatology 2013; 57:625-36. [PMID: 22991197 DOI: 10.1002/hep.26082] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2012] [Accepted: 09/04/2012] [Indexed: 12/31/2022]
Abstract
UNLABELLED As the result of an increasing incidence and a prevalent therapy resistance of hepatocellular carcinoma (HCC), there is a strong need for novel strategies to enhance treatment responses in HCC. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been proposed as a promising anticancer drug because it can selectively induce apoptosis in cancer cells, but not in healthy cells. Nevertheless, most tumor cells show TRAIL resistance, emphasizing the requirement for apoptosis-sensitizing agents and TRAIL molecules with improved tumor specificity. In this study, we employed a recombinant TRAIL molecule, in which three TRAIL protomers were expressed as a single polypeptide chain (scTRAIL), and a novel TRAIL variant, in which scTRAIL was additionally fused to an antibody fragment recognizing epidermal growth factor receptor (EGFR) to improve its HCC-targeting properties. We analyzed the proapoptotic effects of both TRAIL versions in combination with the proteasome inhibitor bortezomib (BZB) in hepatoma cells and primary human hepatocytes as well as in intact explants from HCC and healthy liver tissue. We demonstrate that EGFR-targeted TRAIL in combination with BZB induced significantly higher caspase activation and cell death in hepatoma cells, but not in primary hepatocytes. Importantly, when incubated with fresh liver explants, the combination of EGFR-targeted TRAIL and BZB displayed selective cytotoxicity for HCC, but not for tumor-free liver tissue, which could even be verified in liver explants from the same individuals. Unlike nontargeted TRAIL, EGFR-targeted TRAIL combined with BZB exerted no toxicity in liver tissues from nonalcoholic fatty liver disease patients. CONCLUSION EGFR-targeted TRAIL reveals increased antitumor activity toward HCC without inducing toxicity to tumor-free liver tissue and might therefore represent a promising novel strategy for HCC treatment.
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Affiliation(s)
- Kristin Wahl
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, Hannover, Germany
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13
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Beyerle A, Rueger R, Scholz A, Kontermann R, Heidenreich O. Targeted siRNA delivery to myeloid precursor cells. Klin Padiatr 2011. [DOI: 10.1055/s-0031-1277093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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14
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Zettlitz KA, Lorenz V, Landauer K, Münkel S, Herrmann A, Scheurich P, Pfizenmaier K, Kontermann R. ATROSAB, a humanized antagonistic anti-tumor necrosis factor receptor one-specific antibody. MAbs 2010; 2:639-47. [PMID: 20935477 DOI: 10.4161/mabs.2.6.13583] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Tumor necrosis factor (TNF) signals through two membrane receptors, TNFR1 and TNFR2, and TNFR1 is known to be the major pathogenic mediator of chronic and acute inflammatory diseases. Present clinical intervention is based on neutralization of the ligand TNF. Selective inhibition of TNF receptor 1 (TNFR1) provides an alternative opportunity to neutralize the pro-inflammatory activity of TNF while maintaining the advantageous immunological responses mediated by TNFR2, including immune regulation, tissue homeostasis and neuroprotection. We recently humanized a mouse anti-human TNFR1 monoclonal antibody exhibiting TNFR1-neutralizing activity. This humanized antibody has been converted into an IgG1 molecule (ATROSAB) containing a modified Fc region previously demonstrated to have greatly reduced effector functions. Purified ATROSAB, produced in CHO cells, showed strong binding to human and rhesus TNFR1-Fc fusion protein and mouse embryonic fibroblasts transfected with a recombinant TNFR1 fusion protein with an affinity identical to the parental mouse antibody H398. Using chimeric human/mouse TNFR1 molecules, the epitope of ATROSAB was mapped to the N-terminal region (amino acid residues 1-70) comprising the first cysteine-rich domain (CRD1) and the A1 sub-domain of CRD2. In vitro, ATROSAB inhibited typical TNF-mediated responses like apoptosis induction and activation of NFκB-dependent gene expression such as IL-6 and IL-8 production. These findings open the way to further analyze the therapeutic activity of ATROSAB in relevant disease models in non-human primates.
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Affiliation(s)
- Kirstin A Zettlitz
- Institut für Zellbiologie und Immunologie, Universität Stuttgart, Stuttgart, Germany
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15
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Kontermann R, Dübel S. Anti-Histidine Antibodies as Tools for Reversible Capturing of His-Tagged Fusion Proteins for Subsequent Binding Analysis. Antibody Engineering 2010. [PMCID: PMC7115108 DOI: 10.1007/978-3-642-01144-3_42] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The hexahistidine tag is one of most commonly used fusion tags in affinity purification of recombinantly expressed proteins. Real-time binding analysis using Biacore technology allows in-depth characterization of respective association and dissociation patterns of potential binders. Here we tested four commercially available anti-His antibodies for reversible capturing of His-tagged proteins as a basis for a subsequent interaction analysis with non-His-tagged proteins. Anti-penta-, anti-hexa- and anti-RGS-(His)4 antibodies from different distributors were covalently coupled to Biacore sensor chips. Parallel binding studies of 12 heterogeneously sized RGS-(His)6-tagged (Arg-Gly-Ser-(His)6) proteins revealed that the slowest dissociation rate was obtained when using an anti-RGS-(His)4 antibody. Thus in a sandwich binding assay the anti-RGS-(His)4 antibody can be utilized as an appropriate tool for stable yet reversible capturing of RGS-(His)6-tagged proteins with a non-His-tagged protein.
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Affiliation(s)
- Roland Kontermann
- (Biomedical Engineering) Institut für Zellbiologie und Immunologie, Universität Stuttgart, Allmandring 31, 70569 Stuttgart, Germany
| | - Stefan Dübel
- Technische Universität Braunschweig, Institut für Biochemie und Biotechnologie, Spielmannstraße 7, 38106 Braunschweig Germany
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16
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Dübel S, Breitling F, Kontermann R, Schmidt T, Skerra A, Little M. Bifunctional and multimeric complexes of streptavidin fused to single chain antibodies (scFv). J Immunol Methods 1995; 178:201-9. [PMID: 7836782 DOI: 10.1016/0022-1759(94)00257-w] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.6] [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: 01/27/2023]
Abstract
Multivalent and multispecific antibodies with defined stoichiometry could provide valuable tools for biological and medical research and for the diagnosis and therapy of cancer. We have therefore fused single chain antibodies (scFv) with core-streptavidin. This chimeric protein, expressed by the vector pSTE-215 (plasmid for streptavidin-tagged expression), can form tetrameric complexes, binds antigen and contains the biotin binding site which may be used for further complex formation. An additional cysteine was inserted near the carboxy terminus to facilitate the construction of covalently linked bifunctional molecules. The scFv fusion protein could be purified by affinity chromatography using biotin analogues. We have also shown that the scFv fusion protein could be used for direct detection of its antigen in ELISA and Western blots when stained with biotinylated horseradish peroxidase.
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Affiliation(s)
- S Dübel
- German Cancer Research Center, Recombinant Antibody Research Unit, Heidelberg, Germany
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17
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Ng SW, Wiedemann M, Kontermann R, Petersen G. Molecular characterization of a putative peroxidase gene of Drosophila melanogaster. Biochim Biophys Acta 1992; 1171:224-8. [PMID: 1482687 DOI: 10.1016/0167-4781(92)90127-l] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have identified genomic clones and corresponding cDNAs that encode a putative peroxidase of Drosophila melanogaster. The gene (DmPO) appears as a single copy gene located on the third chromosome at position 89 D/E. It is interrupted by seven small introns and one unusually large 5' intron (about 11 kb). Sequence analysis of the cDNA showed an open reading frame of 690 amino acids resulting in a protein of 77 kDa. The deduced amino acid sequence reveals an overall homology to myeloeosinophil and thyroid peroxidase, a human superfamily of peroxidases.
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Affiliation(s)
- S W Ng
- Institut für Molekulare Genetik, Universität Heidelberg, Germany
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18
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Kontermann R, Bautz EK. Similarity between subunit 8 of yeast RNA polymerase II (RPB8) and the second-largest subunits of eukaryotic RNA polymerases. Nucleic Acids Res 1992; 20:5231. [PMID: 1408842 PMCID: PMC334315 DOI: 10.1093/nar/20.19.5231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- R Kontermann
- Institute of Molecular Genetics, University of Heidelberg, Germany
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19
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Seifarth W, Petersen G, Kontermann R, Riva M, Huet J, Bautz EK. Identification of the genes coding for the second-largest subunits of RNA polymerases I and III of Drosophila melanogaster. Mol Gen Genet 1991; 228:424-32. [PMID: 1910149 DOI: 10.1007/bf00260636] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We have isolated cDNA and genomic clones of Drosophila melanogaster by cross-hybridization with a 658 bp fragment of the yeast gene coding for the second-largest subunit of RNA polymerase III (RET1). Determination of the sequence by comparison of genomic and cDNA regions reveals an ORF of 3405 nucleotides which is interrupted in the genomic sequence by an intron of 48 bp. The deduced polypeptide consists of 1135 amino acids with a calculated molecular weight of 128 kDa. The protein sequence shows the same conserved regions of homology as those observed for all the second-largest subunits of RNA polymerases cloned so far. The gene (DmRP128) obviously codes for a second-largest subunit of an RNA polymerase which is different from DmRP140 and DmRP135. We have purified three distinct RNA polymerase activities from D. melanogaster. By using specific RNA polymerase inhibitors in enzyme assays and by comparing their subunit composition we were able to distinguish between RNA polymerase I, II, and III. RNA polymerase preparations of D. melanogaster were blotted and the second-largest subunits were identified with antibodies raised against polypeptides expressed from DmRP128 and DmRP135. Anti-DmRP135 antibodies react strongly with the second-largest subunit of RNA polymerase I but do not react with the respective subunits of RNA polymerase II and III. The second-largest subunit of RNA polymerase III is only recognized by anti-DmRP128. Previously, we have claimed that DmRP135 codes for the second-largest subunit of RNA polymerase III.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- W Seifarth
- Institut für Molekulare Genetik, Universität Heidelberg, Federal Republic of Germany
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20
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Kontermann R, Deppisch R, Rauterberg EW. Several epitopes on native human complement C9 are involved in interaction with the C5b-8 complex and other C9 molecules. Eur J Immunol 1990; 20:623-8. [PMID: 1690659 DOI: 10.1002/eji.1830200324] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [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: 12/28/2022]
Abstract
Ten monoclonal antibodies (mAb) against native human C9 exhibiting various inhibitory effects on the hemolytic activity of C9 (Bausback, J., Kontermann, R. and Rauterberg, E. W., Immunobiology 1988. 178: 58) were further analyzed regarding their reactivities with monomeric C9 (mC9), polymerized C9 (pC9), and the non-lytic SC5b-9 complex in enzyme-linked immunosorbent assay and with the membrane attack complex (MAC) generated on rabbit erythrocytes analyzed by flow cytometry. In addition, the inhibitory effects of mAb on zinc-induced C9 polymerization were investigated. One epitope of the C-terminal half of C9b exposed on the surface of pC9 and the MAC seems not to participate directly in lytic function or polymerization since no inhibitory effect of the respective mAb was observed. The nine other mAb directed against epitopes of the C9a part exhibit various inhibitory potentials. The mAb inhibit either hemolysis or polymerization, or both processes. Due to the reactivity with the tested antigens the mAb can be divided into two groups. mAb of the first group bind with nearly the same affinity to all four antigens, whereas mAb of the second group react preferentially with mC9 while their affinity to pC9, SC5b-9 and the MAC is reduced. Comparison of reaction patterns and inhibitory effects strongly suggest that different epitopes on the surface of native C9 are involved in interaction of C9 with C5b-8 and/or in C9-C9 interaction. The finding that mAb inhibiting polymerization of C9 in vitro have no inhibitory effect on hemolysis confirms that C9 polymers are no prerequisite for lysis.
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Affiliation(s)
- R Kontermann
- Institut für Immunologie, Universität Heidelberg, FRG
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21
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Abstract
The effect of enzymatic deglycosylation of human complement component C9 on its hemolytic activity was investigated. Treatment of native C9 (Mr 71,000) with glyocpeptidase F (PNGase F) results in a stepwise decrease of the mol. wt. The formation of an Mr 67,000 peptide which is further converted to Mr 63,000 suggests that there are two N-linked carbohydrate chains per C9 polypeptide. Removal of approximately 88% of the N-linked oligosaccharides results in 80% reduction of the hemolytic activity (CH50). The completely N-deglycosylated Mr 63,000 peptide contains a remaining amount of 25% of the total carbohydrates of native C9. These glycans are assumed to be O-linked and predominantly attached to the C9a part of C9. The electrophoretic mobility of C9 is not affected by endoglycosidase F or H treatments revealing that the two N-linked glycans are of the tri- or tetra-antennary complex type. Cleavage of terminal sialic acids from native C9 by neuraminidase results in an Mr 67,000 product with nearly unaltered hemolytic activity. In contrast to other glycoproteins in which deglycosylation remained without major effects on their functional activity, our findings suggest that the N-linked carbohydrates are required for full expression of hemolytic activity of C9.
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Affiliation(s)
- R Kontermann
- Institute of Immunology, University of Heidelberg, F.R.G
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22
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Kontermann R, Sitzler S, Seifarth W, Petersen G, Bautz EK. Primary structure and functional aspects of the gene coding for the second-largest subunit of RNA polymerase III of Drosophila. Mol Gen Genet 1989; 219:373-80. [PMID: 2482932 DOI: 10.1007/bf00259609] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We have cloned and sequenced the gene coding for the second-largest subunit of RNA polymerase III of Drosophila melanogaster (DmRP135). The gene, interrupted by two introns of 62 and 59 bp, respectively, codes for an mRNA of 3.6 kb. As for other housekeeping genes transcription initiates at several sites (between positions -98 and -76) none of which is preceded by a clear TATA sequence. The deduced polypeptide consists of 1129 amino acids with an aggregate molecular weight of 128 kDa. The protein sequence features the same regions of similarity as observed for the corresponding subunits of RNA polymerase II of Drosophila and yeast and the Escherichia coli beta subunit. As in the second-largest subunit of RNA polymerase II there is a zinc-binding motif which is absent in the beta subunit of E. coli. Antibodies directed against a fusion protein expressing 164 amino acids of the DmRP135 polypeptide cross-react with the second-largest subunit of RNA polymerase III of yeast and generate a distinct banding pattern on Drosophila polytene chromosomes distinguishable from that obtained with anti-RNA polymerase II antibodies.
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Affiliation(s)
- R Kontermann
- Institut für Molekulare Genetik, Universität Heidelberg, Federal Republic of Germany
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