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Singh AV, Laux P, Luch A, Sudrik C, Wiehr S, Wild AM, Santomauro G, Bill J, Sitti M. Review of emerging concepts in nanotoxicology: opportunities and challenges for safer nanomaterial design. Toxicol Mech Methods 2019; 29:378-387. [DOI: 10.1080/15376516.2019.1566425] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Ajay Vikram Singh
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
| | - Peter Laux
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Andreas Luch
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Chaitanya Sudrik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Stefan Wiehr
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
| | - Anna-Maria Wild
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
| | - Giulia Santomauro
- Institute for Materials Science, University of Stuttgart, Stuttgart, Germany
| | - Joachim Bill
- Institute for Materials Science, University of Stuttgart, Stuttgart, Germany
| | - Metin Sitti
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
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2
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Maier FC, Wild AM, Kirchen N, Holm F, Fuchs K, Schwenck J, Maurer A, Wiehr S. Comparative immuno-Cerenkov luminescence and -PET imaging enables detection of PSMA+ tumors in mice using 64Cu-radiolabeled monoclonal antibodies. Appl Radiat Isot 2019; 143:149-155. [DOI: 10.1016/j.apradiso.2018.09.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 07/12/2018] [Accepted: 09/07/2018] [Indexed: 01/29/2023]
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Morad HOJ, Wild AM, Wiehr S, Davies G, Maurer A, Pichler BJ, Thornton CR. Pre-clinical Imaging of Invasive Candidiasis Using ImmunoPET/MR. Front Microbiol 2018; 9:1996. [PMID: 30190717 PMCID: PMC6115526 DOI: 10.3389/fmicb.2018.01996] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 08/08/2018] [Indexed: 12/17/2022] Open
Abstract
The human commensal yeast Candida is the fourth most common cause of hospital-acquired bloodstream infections, with Candida albicans accounting for the majority of the >400,000 life-threatening infections annually. Diagnosis of invasive candidiasis (IC), a disease encompassing candidemia (blood-borne yeast infection) and deep-seated organ infections, is a major challenge since clinical manifestations of the disease are indistinguishable from viral, bacterial and other fungal diseases, and diagnostic tests for biomarkers in the bloodstream such as PCR, ELISA, and pan-fungal β-D-glucan lack either standardization, sensitivity, or specificity. Blood culture remains the gold standard for diagnosis, but test sensitivity is poor and turn-around time slow. Furthermore, cultures can only be obtained when the yeast resides in the bloodstream, with samples recovered from hematogenous infections often yielding negative results. Consequently, there is a pressing need for a diagnostic test that allows the identification of metastatic foci in deep-seated Candida infections, without the need for invasive biopsy. Here, we report the development of a highly specific mouse IgG3 monoclonal antibody (MC3) that binds to a putative β-1,2-mannan epitope present in high molecular weight mannoproteins and phospholipomannans on the surface of yeast and hyphal morphotypes of C. albicans, and its use as a [64Cu]NODAGA-labeled tracer for whole-body pre-clinical imaging of deep-seated C. albicans infections using antibody-guided positron emission tomography and magnetic resonance imaging (immunoPET/MRI). When used in a mouse intravenous (i.v.) challenge model that faithfully mimics disseminated C. albicans infections in humans, the [64Cu]NODAGA-MC3 tracer accurately detects infections of the kidney, the principal site of blood-borne candidiasis in this model. Using a strain of the emerging human pathogen Candida auris that reacts with MC3 in vitro, but which is non-infective in i.v. challenged mice, we demonstrate the accuracy of the tracer in diagnosing invasive infections in vivo. This pre-clinical study demonstrates the principle of using antibody-guided molecular imaging for detection of deep organ infections in IC, without the need for invasive tissue biopsy.
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Affiliation(s)
- Hassan O J Morad
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Anna-Maria Wild
- Department of Physical Intelligence, Max Planck Institute for Intelligent Systems, Stuttgart, Germany.,Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Stefan Wiehr
- Department of Physical Intelligence, Max Planck Institute for Intelligent Systems, Stuttgart, Germany.,Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Genna Davies
- ISCA Diagnostics Ltd. and Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Andreas Maurer
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Bernd J Pichler
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Christopher R Thornton
- ISCA Diagnostics Ltd. and Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
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4
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Sauter AW, Mansi R, Hassiepen U, Muller L, Panigada T, Wiehr S, Wild AM, Geistlich S, Béhé M, Rottenburger C, Wild D, Fani M. Targeting of the Cholecystokinin-2 Receptor with the Minigastrin Analog 177Lu-DOTA-PP-F11N: Does the Use of Protease Inhibitors Further Improve In Vivo Distribution? J Nucl Med 2018; 60:393-399. [PMID: 30002107 DOI: 10.2967/jnumed.118.207845] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 06/29/2018] [Indexed: 12/19/2022] Open
Abstract
Patients with metastatic medullary thyroid cancer (MTC) have limited systemic treatment options. The use of radiolabeled gastrin analogs targeting the cholecystokinin-2 receptor (CCK2R) is an attractive approach. However, their therapeutic efficacy is presumably decreased by their enzymatic degradation in vivo. We aimed to investigate whether the chemically stabilized analog 177Lu-DOTA-PP-F11N (177Lu-DOTA-(dGlu)6-Ala-Tyr-Gly-Trp-Nle-Asp-Phe-NH2) performs better than reference analogs with varying in vivo stability, namely 177Lu-DOTA-MG11 (177Lu-DOTA-dGlu-Ala-Tyr-Gly-Trp-Met-Asp-Phe-NH2) and 177Lu-DOTA-PP-F11 (177Lu-DOTA-(dGlu)6-Ala-Tyr-Gly-Trp-Met-Asp-Phe-NH2), and whether the use of protease inhibitors further improves CCKR2 targeting. First human data on 177Lu-DOTA-PP-F11N are also reported. Methods: In vitro stability of all analogs was assessed against a panel of extra- and intracellular endoproteases, whereas their in vitro evaluation was performed using the human MTC MZ-CRC-1 and the transfected A431-CCK2R(+) cell lines. Biodistribution without and with the protease inhibitors phosphoramidon and thiorphan was assessed 4 h after injection in MZ-CRC-1 and A431-CCK2R(+) dual xenografts. Autoradiography of 177Lu-DOTA-PP-F11N (without and with phosphoramidon) and NanoSPECT/CT were performed. SPECT/CT images of 177Lu-DOTA-PP-F11N in a metastatic MTC patient were also acquired. Results: natLu-DOTA-PP-F11N is less of a substrate for neprilysins than the other analogs, whereas intracellular cysteine proteases, such as cathepsin-L, might be involved in the degradation of gastrin analogs. The uptake of all radiotracers was higher in MZ-CRC-1 tumors than in A431-CCK2R(+), apparently because of the higher number of binding sites on MZ-CRC-1 cells. 177Lu-DOTA-PP-F11N had the same biodistribution as 177Lu-DOTA-PP-F11; however, uptake in the MZ-CRC-1 tumors was almost double (20.7 ± 1.71 vs. 11.2 ± 2.94 %IA [percentage injected activity]/g, P = 0.0002). Coadministration of phosphoramidon or thiorphan increases 177Lu-DOTA-MG11 uptake significantly in the CCK2R(+) tumors and stomach. Less profound was the effect on 177Lu-DOTA-PP-F11, whereas no influence or even reduction was observed for 177Lu-DOTA-PP-F11N (20.7 ± 1.71 vs. 15.6 ± 3.80 [with phosphoramidon] %IA/g, P < 0.05 in MZ-CRC-1 tumors). The first clinical data show high 177Lu-DOTA-PP-F11N accumulation in tumors, stomach, kidneys, and colon. Conclusion: The performance of 177Lu-DOTA-PP-F11N without protease inhibitors is as good as the performance of 177Lu-DOTA-MG11 in the presence of inhibitors. The human application of single compounds without unessential additives is preferable. Preliminary clinical data spotlight the stomach as a potential dose-limiting organ besides the kidneys.
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Affiliation(s)
- Alexander W Sauter
- Division of Nuclear Medicine, University Hospital Basel, Basel, Switzerland.,Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | - Rosalba Mansi
- Division of Radiopharmaceutical Chemistry, University Hospital Basel, Basel, Switzerland
| | - Ulrich Hassiepen
- Novartis Pharma AG, Institutes for Biomedical Research, Novartis Campus, Basel, Switzerland; and
| | - Lionel Muller
- Novartis Pharma AG, Institutes for Biomedical Research, Novartis Campus, Basel, Switzerland; and
| | - Tania Panigada
- Novartis Pharma AG, Institutes for Biomedical Research, Novartis Campus, Basel, Switzerland; and
| | - Stefan Wiehr
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | - Anna-Maria Wild
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | - Susanne Geistlich
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, Villigen, Switzerland
| | - Martin Béhé
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, Villigen, Switzerland
| | | | - Damian Wild
- Division of Nuclear Medicine, University Hospital Basel, Basel, Switzerland
| | - Melpomeni Fani
- Division of Radiopharmaceutical Chemistry, University Hospital Basel, Basel, Switzerland
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5
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Huang X, Wiehr S, Wild AM, Voßberg P, Hoffmann W, Grüner B, Köhler C, Soboslay PT. The effects of taxanes, vorinostat and doxorubicin on growth and proliferation of Echinococcus multilocularis metacestodes assessed with magnetic resonance imaging and simultaneous positron emission tomography. Oncotarget 2018; 9:9073-9087. [PMID: 29507675 PMCID: PMC5823665 DOI: 10.18632/oncotarget.24142] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 01/02/2018] [Indexed: 01/08/2023] Open
Abstract
Cytostatic drugs used in cancer therapy were evaluated for their capacity to inhibit Echinococcus multilocularis metacestode growth and proliferation. Metacestode tissues were exposed in vitro to docetaxel, doxorubicin, navelbine, paclitaxel, and vorinostat for 1 week, then incubated in drug-free culture, and thereafter metacestodes were injected into the peritoneum of Meriones unguiculatus. Magnetic resonance imaging (MRI) and simultaneous positron emission tomography (PET) were applied to monitor in vivo growth of drug-exposed E. multilocularis in Meriones. At 3 month p.i., docetaxel (at 10 μM, 5 μM and 2 μM) inhibited in vivo growth and proliferation of E. multilocularis, and at 5 months p.i., only in the 2 μM docetaxel exposure group 0.3 cm 3 of parasite tissue was found. With paclitaxel and navelbine the in vivo growth of metacestodes was suppressed until 3 months p.i., thereafter, parasite tissues enlarged up to 3 cm 3 in both groups. E. multilocularis tissues of more than 10 g developed in Meriones injected with metacestodes which were previously exposed in vitro to doxorubicin, navelbine, paclitaxel or vorinostat. In Meriones infected with metacestodes previously exposed to docetaxel, the in vivo grown parasite tissues weighted 0.2 g. In vitro cultured E. multilocularis metacestodes exposed to docetaxel did not produce vesicles until 7 weeks post drug exposure, while metacestodes exposed to doxorubicin, navelbine and vorinostat proliferated continuously. In summary, docetaxel, and less efficaciously paclitaxel, inhibited in vivo and in vitro parasite growth and proliferation, and these observations suggest further experimental studies with selected drug combinations which may translate into new treatment options against alveolar echinococcosis.
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Affiliation(s)
- Xiangsheng Huang
- Institute for Tropical Medicine, Eberhard Karls University, Tübingen, Germany
| | - Stefan Wiehr
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tübingen, Germany
| | - Anna-Maria Wild
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tübingen, Germany
| | - Patrick Voßberg
- Institute for Tropical Medicine, Eberhard Karls University, Tübingen, Germany
| | - Wolfgang Hoffmann
- Institute for Tropical Medicine, Eberhard Karls University, Tübingen, Germany
| | - Beate Grüner
- Section of Clinical Immunology and Infectiology, University Clinics Ulm, Ulm, Germany
| | - Carsten Köhler
- Institute for Tropical Medicine, Eberhard Karls University, Tübingen, Germany
| | - Peter T Soboslay
- Institute for Tropical Medicine, Eberhard Karls University, Tübingen, Germany
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6
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Honndorf VS, Wiehr S, Rolle AM, Schmitt J, Kreft L, Quintanilla-Martinez L, Kohlhofer U, Reischl G, Maurer A, Boldt K, Schwarz M, Schmidt H, Pichler BJ. Preclinical evaluation of the anti-tumor effects of the natural isoflavone genistein in two xenograft mouse models monitored by [18F]FDG, [18F]FLT, and [64Cu]NODAGA-cetuximab small animal PET. Oncotarget 2017; 7:28247-61. [PMID: 27070087 PMCID: PMC5053724 DOI: 10.18632/oncotarget.8625] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 02/28/2016] [Indexed: 12/11/2022] Open
Abstract
The natural phytoestrogen genistein is known as protein kinase inhibitor and tumor suppressor in various types of cancers. We studied its antitumor effect in two different xenograft models using positron emission tomography (PET) in vivo combined with ex vivo histology and nuclear magnetic resonance (NMR) metabolic fingerprinting.
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Affiliation(s)
- Valerie S Honndorf
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | - Stefan Wiehr
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | - Anna-Maria Rolle
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | - Julia Schmitt
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | - Luisa Kreft
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | | | - Ursula Kohlhofer
- Institute of Pathology, University Hospital, Eberhard Karls University, Tuebingen, Germany
| | - Gerald Reischl
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | - Andreas Maurer
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
| | - Karsten Boldt
- Medical Proteome Center, Institute for Ophthalmic Research, Eberhard Karls University, Tuebingen, Germany
| | - Michael Schwarz
- Institute of Experimental and Clinical Pharmacology and Toxicology, Department of Toxicology, Eberhard Karls University, Tuebingen, Germany
| | - Holger Schmidt
- Department of Radiology, Diagnostic and Interventional Radiology, Eberhard Karls University, Tuebingen, Germany
| | - Bernd J Pichler
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tuebingen, Germany
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7
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Wiehr S, Warnke P, Rolle AM, Schütz M, Oberhettinger P, Kohlhofer U, Quintanilla-Martinez L, Maurer A, Thornton C, Boschetti F, Reischl G, Autenrieth IB, Pichler BJ, Autenrieth SE. New pathogen-specific immunoPET/MR tracer for molecular imaging of a systemic bacterial infection. Oncotarget 2017; 7:10990-1001. [PMID: 26934329 PMCID: PMC4905453 DOI: 10.18632/oncotarget.7770] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [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: 10/01/2015] [Accepted: 02/20/2016] [Indexed: 01/12/2023] Open
Abstract
The specific and rapid detection of Enterobacteriaceae, the most frequent cause of gram-negative bacterial infections in humans, remains a major challenge. We developed a non-invasive method to rapidly detect systemic Yersinia enterocolitica infections using immunoPET (antibody-targeted positron emission tomography) with [64Cu]NODAGA-labeled Yersinia-specific polyclonal antibodies targeting the outer membrane protein YadA. In contrast to the tracer [18F]FDG, [64Cu]NODAGA-YadA uptake co-localized in a dose dependent manner with bacterial lesions of Yersinia-infected mice, as detected by magnetic resonance (MR) imaging. This was accompanied by elevated uptake of [64Cu]NODAGA-YadA in infected tissues, in ex vivo biodistribution studies, whereas reduced uptake was observed following blocking with unlabeled anti-YadA antibody. We show, for the first time, a bacteria-specific, antibody-based, in vivo imaging method for the diagnosis of a Gram-negative enterobacterial infection as a proof of concept, which may provide new insights into pathogen-host interactions.
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Affiliation(s)
- Stefan Wiehr
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Philipp Warnke
- Institute of Medical Microbiology and Hygiene, Eberhard Karls University, Tübingen, Germany.,Institute of Medical Microbiology, Virology and Hygiene, Rostock University Hospital, Rostock, Germany
| | - Anna-Maria Rolle
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Monika Schütz
- Institute of Medical Microbiology and Hygiene, Eberhard Karls University, Tübingen, Germany
| | - Philipp Oberhettinger
- Institute of Medical Microbiology and Hygiene, Eberhard Karls University, Tübingen, Germany
| | - Ursula Kohlhofer
- Institute of Pathology, Eberhard Karls University Tübingen, Tübingen, Germany
| | | | - Andreas Maurer
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Christopher Thornton
- Biosciences and ISCA Diagnostics Ltd., University of Exeter, Exeter, United Kingdom
| | | | - Gerald Reischl
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Ingo B Autenrieth
- Institute of Medical Microbiology and Hygiene, Eberhard Karls University, Tübingen, Germany
| | - Bernd J Pichler
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Stella E Autenrieth
- Department of Internal Medicine II, University Hospital Tübingen, Tübingen, Germany
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8
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Davies G, Rolle AM, Maurer A, Spycher PR, Schillinger C, Solouk-Saran D, Hasenberg M, Weski J, Fonslet J, Dubois A, Boschetti F, Denat F, Gunzer M, Eichner M, Ryder LS, Jensen M, Schibli R, Pichler BJ, Wiehr S, Thornton CR. Towards Translational ImmunoPET/MR Imaging of Invasive Pulmonary Aspergillosis: The Humanised Monoclonal Antibody JF5 Detects Aspergillus Lung Infections In Vivo. Am J Cancer Res 2017; 7:3398-3414. [PMID: 28912884 PMCID: PMC5596432 DOI: 10.7150/thno.20919] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 07/04/2017] [Indexed: 01/07/2023] Open
Abstract
Invasive pulmonary aspergillosis (IPA) is a life-threatening lung disease of hematological malignancy or bone marrow transplant patients caused by the ubiquitous environmental fungus Aspergillus fumigatus. Current diagnostic tests for the disease lack sensitivity as well as specificity, and culture of the fungus from invasive lung biopsy, considered the gold standard for IPA detection, is slow and often not possible in critically ill patients. In a previous study, we reported the development of a novel non-invasive procedure for IPA diagnosis based on antibody-guided positron emission tomography and magnetic resonance imaging (immunoPET/MRI) using a [64Cu]DOTA-labeled mouse monoclonal antibody (mAb), mJF5, specific to Aspergillus. To enable translation of the tracer to the clinical setting, we report here the development of a humanised version of the antibody (hJF5), and pre-clinical imaging of lung infection using a [64Cu]NODAGA-hJF5 tracer. The humanised antibody tracer shows a significant increase in in vivo biodistribution in A. fumigatus infected lungs compared to its radiolabeled murine counterpart [64Cu]NODAGA-mJF5. Using reverse genetics of the pathogen, we show that the antibody binds to the antigenic determinant β1,5-galactofuranose (Galf) present in a diagnostic mannoprotein antigen released by the pathogen during invasive growth in the lung. The absence of the epitope Galf in mammalian carbohydrates, coupled with the enhanced imaging capabilities of the hJF5 antibody, means that the [64Cu]NODAGA-hJF5 tracer developed here represents an ideal candidate for the diagnosis of IPA and translation to the clinical setting.
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9
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Schwenck J, Maier FC, Kneilling M, Wiehr S, Fuchs K. Non-invasive In Vivo Fluorescence Optical Imaging of Inflammatory MMP Activity Using an Activatable Fluorescent Imaging Agent. J Vis Exp 2017. [PMID: 28518078 DOI: 10.3791/55180] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
This paper describes a non-invasive method for imaging matrix metalloproteinases (MMP)-activity by an activatable fluorescent probe, via in vivo fluorescence optical imaging (OI), in two different mouse models of inflammation: a rheumatoid arthritis (RA) and a contact hypersensitivity reaction (CHR) model. Light with a wavelength in the near infrared (NIR) window (650 - 950 nm) allows a deeper tissue penetration and minimal signal absorption compared to wavelengths below 650 nm. The major advantages using fluorescence OI is that it is cheap, fast and easy to implement in different animal models. Activatable fluorescent probes are optically silent in their inactivated states, but become highly fluorescent when activated by a protease. Activated MMPs lead to tissue destruction and play an important role for disease progression in delayed-type hypersensitivity reactions (DTHRs) such as RA and CHR. Furthermore, MMPs are the key proteases for cartilage and bone degradation and are induced by macrophages, fibroblasts and chondrocytes in response to pro-inflammatory cytokines. Here we use a probe that is activated by the key MMPs like MMP-2, -3, -9 and -13 and describe an imaging protocol for near infrared fluorescence OI of MMP activity in RA and control mice 6 days after disease induction as well as in mice with acute (1x challenge) and chronic (5x challenge) CHR on the right ear compared to healthy ears.
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Affiliation(s)
- Johannes Schwenck
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University of Tübingen; Department of Nuclear Medicine, Eberhard Karls University of Tübingen
| | - Florian C Maier
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University of Tübingen
| | - Manfred Kneilling
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University of Tübingen; Department of Dermatology, Eberhard Karls University of Tübingen
| | - Stefan Wiehr
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University of Tübingen
| | - Kerstin Fuchs
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University of Tübingen;
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10
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Wiehr S, Rolle AM, Warnke P, Kohlhofer U, Quintanilla-Martinez L, Reischl G, Autenrieth IB, Pichler BJ, Autenrieth SE. The Positron Emission Tomography Tracer 3'-Deoxy-3'-[18F]Fluorothymidine ([18F]FLT) Is Not Suitable to Detect Tissue Proliferation Induced by Systemic Yersinia enterocolitica Infection in Mice. PLoS One 2016; 11:e0164163. [PMID: 27701464 PMCID: PMC5049782 DOI: 10.1371/journal.pone.0164163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 09/20/2016] [Indexed: 11/25/2022] Open
Abstract
Most frequently, gram-negative bacterial infections in humans are caused by Enterobacteriaceae and remain a major challenge in medical diagnostics. We non-invasively imaged moderate and severe systemic Yersinia enterocolitica infections in mice using the positron emission tomography (PET) tracer 3’-deoxy-3’-[18F]fluorothymidine ([18F]FLT), which is a marker of proliferation, and compared the in vivo results to the ex vivo biodistributions, bacterial loads, and histologies of the corresponding organs. Y. enterocolitica infection is detectable with histology using H&E staining and immunohistochemistry for Ki 67. [18F]FLT revealed only background uptake in the spleen, which is the main manifestation site of systemic Y. enterocolitica-infected mice. The uptake was independent of the infection dose. Antibody-based thymidine kinase 1 (Tk-1) staining confirmed the negative [18F]FLT-PET data. Histological alterations of spleen tissue, observed via Ki 67-antibody-based staining, can not be detected by [18F]FLT-PET in this model. Thus, the proliferation marker [18F]FLT is not a suitable tracer for the diagnosis of systemic Y. enterocolitica infection in the C57BL/6 animal model of yersiniosis.
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Affiliation(s)
- Stefan Wiehr
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Anna-Maria Rolle
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Philipp Warnke
- Institute of Medical Microbiology and Hygiene, Eberhard Karls University Tübingen, Tübingen, Germany
- Institute of Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany
| | - Ursula Kohlhofer
- Institute of Pathology, Eberhard Karls University Tübingen, Tübingen, Germany
| | | | - Gerald Reischl
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Ingo B. Autenrieth
- Institute of Medical Microbiology and Hygiene, 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
| | - Stella E. Autenrieth
- Department of Internal Medicine II, University Hospital Tübingen, Tübingen, Germany
- * E-mail:
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11
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Rolle AM, Soboslay PT, Reischl G, Hoffmann WH, Pichler BJ, Wiehr S. Evaluation of the Metabolic Activity of Echinococcus multilocularis in Rodents Using Positron Emission Tomography Tracers. Mol Imaging Biol 2016; 17:512-20. [PMID: 25561014 DOI: 10.1007/s11307-014-0815-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
PURPOSE 2-Deoxy-2-[(18)F]fluoro-D-glucose ([(18)F]FDG) has been used as a standard clinical positron emission tomography (PET) tracer for the follow-up of the rare but life-threatening parasitic disease alveolar echinococcosis (AE). Given that the disease is endemic in many countries in the northern hemisphere and the diagnosis is still challenging, the aim of our study was to evaluate further clinically relevant PET tracers as possible diagnostic tools for AE in vitro and in vivo. PROCEDURES Various clinically used PET tracers were evaluated in vitro and assessed in an in vivo AE animal model based on PET/magnetic resonance (MR) measurements. RESULTS In vitro binding assays displayed high uptake of [(18)F]FDG in a cell suspension of E. multilocularis tissue, whereas 3'-deoxy-3'-[(18)F]fluorothymidine ([(18)F]FLT) and [(11)C]choline were found to be taken up strongly by E. multilocularis vesicles. [(18)F]FDG and [(18)F]FLT displayed an elevated uptake in vivo, which appeared as several foci throughout the parasite tissue as opposed to [(18)F]fluoro-azomycinarabinofuranoside ([(18)F]FAZA) and [(11)C]choline. CONCLUSIONS Our data clearly demonstrate that the clinically applied PET tracer [(18)F]FDG is useful for the diagnosis and disease staging of AE but also has drawbacks in the assessment of currently inactive or metabolically weak parasitic lesions. The different tested PET tracers do not show the potential for the replacement or supplementation of current diagnostic strategies. Hence, there is still the need for novel diagnostic tools.
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Affiliation(s)
- Anna-Maria Rolle
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Röntgenweg 13, 72076, Tübingen, Germany
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12
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Honndorf VS, Schmidt H, Wehrl HF, Wiehr S, Ehrlichmann W, Quintanilla-Martinez L, Barjat H, Ricketts SA, Pichler BJ. Quantitative correlation at the molecular level of tumor response to docetaxel by multimodal diffusion-weighted magnetic resonance imaging and [¹⁸F]FDG/[¹⁸F]FLT positron emission tomography. Mol Imaging 2015; 13. [PMID: 25430886 DOI: 10.2310/7290.2014.00045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
We aimed to quantitatively characterize the treatment effects of docetaxel in the HCT116 xenograft mouse model, applying diffusion-weighted magnetic resonance imaging (MRI) and positron emission tomography (PET) using 2-deoxy-2-[¹⁸F]fluoro-d-glucose ([¹⁸F]FDG) and 3'-deoxy-3'-[¹⁸F]-fluorothymidine ([¹⁸F]FLT). Mice were imaged at four time points over 8 days. Docetaxel (15 mg/kg) was administered after a baseline scan. Voxel-wise scatterplots of PET and apparent diffusion coefficient (ADC) data of tumor volumes were evaluated with a threshold cluster analysis and compared to histology (GLUT1, GLUT3, Ki67, activated caspase 3a). Compared to the extensive tumor growth observed in the vehicle-treated group (from 0.32 ± 0.21 cm³ to 0.69 ± 0.40 cm³), the administration of docetaxel led to tumor growth stasis (from 0.32 ± 0.20 cm³ to 0.45 ± 0.23 cm³). The [¹⁸F]FDG/ADC cluster analysis and the evaluation of peak histogram values revealed a significant treatment effect matching histology as opposed to [¹⁸F]FLT/ADC. [¹⁸F]FLT uptake and the Ki67 index were not in good agreement. Our voxel-based cluster analysis uncovered treatment effects not seen in the separate inspection of PET and MRI data and may be used as an independent analysis tool. [¹⁸F]FLT/ADC cluster analysis could still point out the treatment effect; however, [¹⁸F]FDG/ADC reflected the histology findings in higher agreement.
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13
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Wehrl HF, Bezrukov I, Wiehr S, Lehnhoff M, Fuchs K, Mannheim JG, Quintanilla-Martinez L, Kohlhofer U, Kneilling M, Pichler BJ, Sauter AW. Assessment of murine brain tissue shrinkage caused by different histological fixatives using magnetic resonance and computed tomography imaging. Histol Histopathol 2014; 30:601-13. [PMID: 25504583 DOI: 10.14670/hh-30.601] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Especially for neuroscience and the development of new biomarkers, a direct correlation between in vivo imaging and histology is essential. However, this comparison is hampered by deformation and shrinkage of tissue samples caused by fixation, dehydration and paraffin embedding. We used magnetic resonance (MR) imaging and computed tomography (CT) imaging to analyze the degree of shrinkage on murine brains for various fixatives. After in vivo imaging using 7 T MRI, animals were sacrificed and the brains were dissected and immediately placed in different fixatives, respectively: zinc-based fixative, neutral buffered formalin (NBF), paraformaldehyde (PFA), Bouin-Holland fixative and paraformaldehyde-lysine-periodate (PLP). The degree of shrinkage based on mouse brain volumes, radiodensity in Hounsfield units (HU), as well as non-linear deformations were obtained. The highest degree of shrinkage was observed for PLP (68.1%, P < 0.001), followed by PFA (60.2%, P<0.001) and NBF (58.6%, P<0.001). The zinc-based fixative revealed a low shrinkage with only 33.5% (P<0.001). Compared to NBF, the zinc-based fixative shows a slightly higher degree of deformations, but is still more homogenous than PFA. Tissue shrinkage can be monitored non-invasively with CT and MR. Zinc-based fixative causes the smallest degree of brain shrinkage and only small deformations and is therefore recommended for in vivo ex vivo comparison studies.
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Affiliation(s)
- Hans F Wehrl
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Ilja Bezrukov
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, and Department of Empirical Inference, Max-Planck-Institute for Intelligent Systems, Tuebingen, Germany
| | - Stefan Wiehr
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Mareike Lehnhoff
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Kerstin Fuchs
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Julia G Mannheim
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | | | - Ursula Kohlhofer
- Department of Pathology, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Manfred Kneilling
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, and Department of Dermatology, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Bernd J Pichler
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Alexander W Sauter
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, and Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, Tuebingen, Germany.
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Severin GW, Jørgensen JT, Wiehr S, Rolle AM, Hansen AE, Maurer A, Hasenberg M, Pichler B, Kjær A, Jensen AI. The impact of weakly bound ⁸⁹Zr on preclinical studies: non-specific accumulation in solid tumors and aspergillus infection. Nucl Med Biol 2014; 42:360-8. [PMID: 25583221 DOI: 10.1016/j.nucmedbio.2014.11.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 11/11/2014] [Accepted: 11/14/2014] [Indexed: 01/12/2023]
Abstract
UNLABELLED Preclinical studies involving (89)Zr often report significant bone accumulation, which is associated with dissociation of the radiometal from the tracer. However, experiments determining the uptake of unbound (89)Zr in disease models are not performed as routine controls. The purpose of the present study was to investigate the impact of free or weakly bound (89)Zr on PET quantifications in disease models, in order to determine if such control experiments are warranted. METHODS Chemical studies were carried out to find a (89)Zr compound that would solubilize the (89)Zr as a weak chelate, thus mimicking free or weakly bound (89)Zr released in circulation. (89)Zr oxalate had the desired characteristics, and was injected into mice bearing FaDu and HT29 solid tumor xenografts, and mice infected in the lungs with the mold Aspergillus fumigatus, as well as in healthy controls (naïve). PET/CT or PET/MR imaging followed to quantify the distribution of the radionuclide in the disease models. RESULTS (89)Zr oxalate was found to have a plasma half-life of 5.1 ± 2.3 h, accumulating mainly in the bones of all animals. Both tumor types accumulated (89)Zr on the order of 2-4 %ID/cm(3), which is comparable to EPR-mediated accumulation of certain species. In the aspergillosis model, the concentration of (89)Zr in lung tissue of the naïve animals was 6.0 ± 1.1 %ID/g. This was significantly different from that of the animals with advanced disease, showing 11.6 ± 1.8 %ID/g. CONCLUSIONS Given the high levels of (89)Zr accumulation in the disease sites in the present study, we recommend control experiments mapping the biodistribution of free (89)Zr in any preclinical study employing (89)Zr where bone uptake is observed. Aqueous (89)Zr oxalate appears to be a suitable compound for such studies. This is especially relevant in studies where the tracer accumulation is based upon passive targeting, such as EPR.
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Affiliation(s)
- Gregory W Severin
- The Hevesy Laboratory, DTU Nutech, Technical University of Denmark; Center for Nanomedicine and Theranostics, Technical University of Denmark
| | - Jesper T Jørgensen
- Dept. of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet and Cluster for Molecular Imaging, Faculty of Health Science, University of Copenhagen, Denmark
| | - Stefan Wiehr
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Anna-Maria Rolle
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Anders E Hansen
- Dept. of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet and Cluster for Molecular Imaging, Faculty of Health Science, University of Copenhagen, Denmark; Center for Nanomedicine and Theranostics, Technical University of Denmark; Department of Micro- and Nanotechnology, DTU Nanotech, Technical University of Denmark
| | - Andreas Maurer
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Mike Hasenberg
- University Duisburg-Essen, University Hospital, Institute for Experimental Immunology and Imaging, Essen, Germany
| | - Bernd Pichler
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Andreas Kjær
- Dept. of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet and Cluster for Molecular Imaging, Faculty of Health Science, University of Copenhagen, Denmark
| | - Andreas I Jensen
- The Hevesy Laboratory, DTU Nutech, Technical University of Denmark; Center for Nanomedicine and Theranostics, Technical University of Denmark.
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Wehrl HF, Wiehr S, Divine MR, Gatidis S, Gullberg GT, Maier FC, Rolle AM, Schwenck J, Thaiss WM, Pichler BJ. Preclinical and Translational PET/MR Imaging. J Nucl Med 2014; 55:11S-18S. [PMID: 24833493 DOI: 10.2967/jnumed.113.129221] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Combined PET and MR imaging (PET/MR imaging) has progressed tremendously in recent years. The focus of current research has shifted from technologic challenges to the application of this new multimodal imaging technology in the areas of oncology, cardiology, neurology, and infectious diseases. This article reviews studies in preclinical and clinical translation. The common theme of these initial results is the complementary nature of combined PET/MR imaging that often provides additional insights into biologic systems that were not clearly feasible with just one modality alone. However, in vivo findings require ex vivo validation. Combined PET/MR imaging also triggers a multitude of new developments in image analysis that are aimed at merging and using multimodal information that ranges from better tumor characterization to analysis of metabolic brain networks. The combination of connectomics information that maps brain networks derived from multiparametric MR data with metabolic information from PET can even lead to the formation of a new research field that we would call cometomics that would map functional and metabolic brain networks. These new methodologic developments also call for more multidisciplinarity in the field of molecular imaging, in which close interaction and training among clinicians and a variety of scientists is needed.
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Affiliation(s)
- Hans F Wehrl
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Stefan Wiehr
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Mathew R Divine
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Sergios Gatidis
- Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Grant T Gullberg
- Department of Radiotracer Development and Imaging Technology, Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California; and
| | - Florian C Maier
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Anna-Maria Rolle
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Johannes Schwenck
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany Department of Nuclear Medicine, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Wolfgang M Thaiss
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Bernd J Pichler
- Werner Siemens Imaging Center, Department for Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Tuebingen, Germany
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Wiehr S, Bühler P, Gierschner D, Wolf P, Rolle AM, Kesenheimer C, Pichler BJ, Elsässer-Beile U. Pharmacokinetics and PET imaging properties of two recombinant anti-PSMA antibody fragments in comparison to their parental antibody. Prostate 2014; 74:743-55. [PMID: 24610028 DOI: 10.1002/pros.22794] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 01/31/2014] [Indexed: 01/10/2023]
Abstract
BACKGROUND Radioimmunoimaging with disease-specific tracers can be advantageous compared to that with nonspecific tracers for the imaging of glucose metabolism and cell proliferation. Monoclonal antibodies (mAbs) or their fragments are excellent tools for immuno-positron emission tomography (PET). In this study, PSMA-specific mAb 3/F11 and its recombinant fragments were compared for the imaging of prostate cancer in xenografts. METHODS Recombinant anti-PSMA antibody fragments D7-Fc and D7-CH3 were constructed by genetically fusing the binding domains of mAb 3/F11 (D7) to the human IgG3 CH3 or CH2-CH3 (Fc) domain. The fragments and the mAb 3/F11 were DOTA conjugated, tested in vitro, and radiolabeled with (64) Cu. PSMA-positive C4-2 and PSMA-negative DU 145 prostate cancer xenografts were used for PET-MR imaging and for ex vivo biodistribution. RESULTS The constructs showed strong and specific binding to PSMA-positive C4-2 cells in vitro which did not decrease after DOTA conjugation. Both tested fragments showed stable accumulation in PSMA-positive C4-2 tumors at all measured time points but reduced uptake compared to the full-length antibody. Other organs and PSMA-negative tumors showed a very low tracer uptake only 3 hr after injection, with the exception of the kidneys, which demonstrated high radioactivity uptake due to rapid renal clearance of the mAb fragments. CONCLUSION Stable tumor uptake and fast serum clearance of the tested radiolabeled fragments was observed in this preclinical study compared to the full length mAb. Since the fragments show rapid and specific tumor uptake, the tested fragments might serve as tools for theranostic imaging with suitable isotopes for radioimmunotherapy.
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Affiliation(s)
- Stefan Wiehr
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University, Tübingen, Germany
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17
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Probst S, Wiehr S, Mantlik F, Schmidt H, Kolb A, Münch P, Delcuratolo M, Stubenrauch F, Pichler BJ, Iftner T. Evaluation of positron emission tomographic tracers for imaging of papillomavirus-induced tumors in rabbits. Mol Imaging 2014; 13. [PMID: 24622808 DOI: 10.2310/7290.2013.00070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In this study, simultaneous positron emission tomography (PET)/magnetic resonance (MR) imaging was employed to evaluate the feasibility of the PET tracers 2-deoxy-2-18F-fluoro-d-glucose (18F-FDG), 11C-choline, and 18F-fluorothymidine (18F-FLT) to detect papillomavirus-induced tumors in an established rabbit model system. The combined PET/MR allowed the analysis of tracer uptake of the tumors using the morphologic information acquired by MR. New Zealand White rabbits were infected with cottontail rabbit papillomavirus genomes and were imaged for up to 10 months with a simultaneous PET/MR system during the course of infection. The uptake characteristics of the PET tracers 11C-choline and 18F-FLT of tumors and reference tissues were examined relative to the clinical standard, 18F-FDG. Tracer biodistribution of various organs was measured by gamma-counting after the last PET scan and compared to the in vivo PET/MR 18F-FDG uptake. Increased tracer uptake was found 2 months postinfection in primary tumors with 18F-FDG and 11C-choline, whereas 18F-FLT failed to detect the tumors at all measured time points. Our data show that the PET tracer 18F-FDG is superior for imaging papillomavirus-induced tumors in rabbits compared to 11C-choline and 18F-FLT. However, 11C-choline imaging, which has previously been applied to detect various tumor entities in patients, appears to be an alternative to 18F-FDG.
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Griessinger CM, Kehlbach R, Bukala D, Wiehr S, Bantleon R, Cay F, Schmid A, Braumüller H, Fehrenbacher B, Schaller M, Eichner M, Sutcliffe JL, Ehrlichmann W, Eibl O, Reischl G, Cherry SR, Röcken M, Pichler BJ, Kneilling M. In Vivo Tracking of Th1 Cells by PET Reveals Quantitative and Temporal Distribution and Specific Homing in Lymphatic Tissue. J Nucl Med 2014; 55:301-7. [DOI: 10.2967/jnumed.113.126318] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Bareiss PM, Paczulla A, Wang H, Schairer R, Wiehr S, Kohlhofer U, Rothfuss OC, Fischer A, Perner S, Staebler A, Wallwiener D, Fend F, Fehm T, Pichler B, Kanz L, Quintanilla-Martinez L, Schulze-Osthoff K, Essmann F, Lengerke C. SOX2 expression associates with stem cell state in human ovarian carcinoma. Cancer Res 2013; 73:5544-55. [PMID: 23867475 DOI: 10.1158/0008-5472.can-12-4177] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The SRY-related HMG-box family of transcription factors member SOX2 regulates stemness and pluripotency in embryonic stem cells and plays important roles during early embryogenesis. More recently, SOX2 expression was documented in several tumor types including ovarian carcinoma, suggesting an involvement of SOX2 in regulation of cancer stem cells (CSC). Intriguingly, however, studies exploring the predictive value of SOX2 protein expression with respect to histopathologic and clinical parameters report contradictory results in individual tumors, indicating that SOX2 may play tumor-specific roles. In this report, we analyze the functional relevance of SOX2 expression in human ovarian carcinoma. We report that in human serous ovarian carcinoma (SOC) cells, SOX2 expression increases the expression of CSC markers, the potential to form tumor spheres, and the in vivo tumor-initiating capacity, while leaving cellular proliferation unaltered. Moreover, SOX2-expressing cells display enhanced apoptosis resistance in response to conventional chemotherapies and TRAIL. Hence, our data show that SOX2 associates with stem cell state in ovarian carcinoma and induction of SOX2 imposes CSC properties on SOC cells. We propose the existence of SOX2-expressing ovarian CSCs as a mechanism of tumor aggressiveness and therapy resistance in human SOC.
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Affiliation(s)
- Petra M Bareiss
- Departments of Internal Medicine II and Preclinical Imaging and Radiopharmacy, Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens-Foundation, University of Tuebingen, Tuebingen, Germany
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Hasenbach K, Wiehr S, Herrmann C, Mannheim J, Cay F, von Kürthy G, Bolmont T, Grathwohl SA, Weller M, Lengerke C, Pichler BJ, Tabatabai G. Monitoring the glioma tropism of bone marrow-derived progenitor cells by 2-photon laser scanning microscopy and positron emission tomography. Neuro Oncol 2012; 14:471-81. [PMID: 22298526 DOI: 10.1093/neuonc/nor228] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Intracerebral experimental gliomas attract intravenously injected murine or human bone marrow-derived hematopoietic progenitor and stem cells (HPC) in vitro, ex vivo, and in vivo, indicating that these progenitor cells might be suitable vehicles for a cell-based delivery of therapeutic molecules to malignant gliomas. With regard to therapeutic application, it is important to investigate cell fates in vivo (i.e., the time-dependent intratumoral and systemic distribution after intravenously injection). Conventional histological analysis has limitations in this regard because longitudinal monitoring is precluded. Here, we used 2-photon laser scanning microscopy (2PLSM), positron emission tomography (PET), and MRI to study the fate of intravenously injected HPC carrying fluorescence, bioluminescence, and PET reporter genes in glioma-bearing mice. Our 2PLSM-based monitoring studies revealed that HPC homing to intracerebral experimental gliomas occurred already within the first 6 h and was most efficient within the first 24 h after intravenous injection. The highest PET signals were detected in intracerebral gliomas, whereas the tracer uptake in other organs, notably spleen, lung, liver, and muscle, remained at background levels. The results have important implications for designing schedules for therapeutic cell-based anti-glioma approaches. Moreover, the PET reporter-based imaging technique will allow noninvasive monitoring of cell fate in future cell-based therapeutic antiglioma approaches.
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Affiliation(s)
- Kathy Hasenbach
- Department of General Neurology, University Hospital Tübingen, Tübingen, Germany
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Schwarz C, Parmentier E, Wiehr S, Gemballa S. The locomotory system of pearlfish Carapus acus: What morphological features are characteristic for highly flexible fishes? J Morphol 2011; 273:519-29. [DOI: 10.1002/jmor.11038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 08/31/2011] [Accepted: 09/27/2011] [Indexed: 11/09/2022]
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Kukuk D, Reischl G, Raguin O, Wiehr S, Judenhofer MS, Calaminus C, Honndorf VS, Quintanilla-Martinez L, Schönberger T, Duchamp O, Machulla HJ, Pichler BJ. Assessment of PET tracer uptake in hormone-independent and hormone-dependent xenograft prostate cancer mouse models. J Nucl Med 2011; 52:1654-63. [PMID: 21859811 DOI: 10.2967/jnumed.110.086702] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED The pharmacokinetics of (18)F-fluorodeoxythymidine (FLT), (18)F-FDG, (11)C-choline, and (18)F-fluoroethylcholine (FEC) in 2 hormone-independent (PC-3, DU145) and 2 hormone-dependent (CWR22, PAC120) prostate cancer xenograft mouse models were evaluated by PET and compared by immunohistochemistry. Further investigation was performed to determine whether PET can detect early changes in tumor metabolism after androgen ablation therapy through surgical castration. METHODS PET was performed on 4 consecutive days. In addition, the CWR22 and PAC120 tumor models were surgically castrated after the baseline measurement and imaged again after castration. The tracer uptake was analyzed using time-activity curves, percentage injected dose per volume (%ID/cm(3)), and tumor-to-muscle ratio (T/M). RESULTS Regarding the hormone-independent prostate tumor models, (18)F-FLT showed the best T/M and highest %ID/cm(3) in PC-3 (2.97 ± 0.63 %ID/cm(3)) and DU145 (2.06 ± 0.75 %ID/cm(3)) tumors. (18)F-FDG seemed to be the tracer of choice for delineation of the PC-3 tumors but not for the DU145 tumors. Using (11)C-choline (PC-3: 1.33 ± 0.29 %ID/cm(3), DU145: 1.60 ± 0.27 %ID/cm(3)) and (18)F-FEC, we did not find any significant uptake in the tumors, compared with muscle tissue. Regarding the hormone-dependent prostate tumor models, the CWR22 model showed a highly significant (P < 0.01) decrease in tumor (18)F-FDG uptake from 4.11 ± 1.29 %ID/cm(3) to 2.19 ± 1.45 %ID/cm(3) after androgen ablation therapy. However, the (18)F-FLT, (11)C-choline, or (18)F-FEC tracers did not provide sufficient uptake or reliable information about therapy response in CWR22 tumors. The PAC120 model showed a significant increase in (18)F-FLT tumor uptake (P = 0.015) after androgen ablation therapy. The accumulation of (18)F-FEC (before: 2.32 ± 1.01 %ID/cm(3), after: 1.36 ± 0.39 %ID/cm(3)) was found to be the next highest after (18)F-FDG (before: 2.45 ± 0.93 %ID/cm(3), after: 2.18 ± 0.65 %ID/cm(3)) in PAC120 tumors before castration and is better suited for monitoring therapy response. CONCLUSION This comprehensive study in 2 hormone-dependent and 2 hormone-independent prostate tumor mouse models shows that (18)F-FLT and (18)F-FDG are the most appropriate tracers for delineation of PC-3, DU145 (except (18)F-FDG), and CWR22 tumors, but not for PAC120 tumors. (18)F-FEC and (11)C-choline, in particular, revealed insufficient T/M ratio in the prostate tumor models. The results may indicate that radiolabeled choline and choline derivatives compete with a high concentration of the precursor dimethylaminoethanol, resulting in reduced uptake in small-rodent tumor models, a hypothesis that is currently under investigation in our laboratory.
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Affiliation(s)
- Damaris Kukuk
- Department of Preclinical Imaging and Radiopharmacy, Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens-Foundation, Eberhard Karls University, Tübingen, Germany
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Alt K, Wiehr S, Ehrlichmann W, Reischl G, Wolf P, Pichler BJ, Elsässer-Beile U, Bühler P. High-resolution animal PET imaging of prostate cancer xenografts with three different 64Cu-labeled antibodies against native cell-adherent PSMA. Prostate 2010; 70:1413-21. [PMID: 20687214 DOI: 10.1002/pros.21176] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The prostate specific membrane antigen (PSMA) is expressed by virtually all prostate cancers and represents an ideal target for diagnostic and therapeutic strategies. This article compares the in vivo behavior and tumor uptake of three different radiolabeled anti-PSMA monoclonal antibodies (mAbs) and corresponding F(ab)(2) and Fab fragments thereof. METHODS The mAbs 3/A12, 3/F11, and 3/E7 and fragments of 3/A12 were conjugated with the chelating agent DOTA and radiolabeled with 64Cu. For the microPET imaging studies, SCID mice bearing PSMA-positive C4-2 and PSMA-negative DU 145 prostate cancer xenografts were used. Each animal received 20-30 microg radiolabeled mAb or fragment corresponding to an activity of 8-14 MBq. Imaging was performed 3, 24, and 48 hr post-injection. After the last scan, mice were sacrificed and tracer in vivo biodistribution was measured by gamma-counting. RESULTS Static microPET images of mice with PSMA-positive tumors revealed a high uptake of the mAbs in the C4-2 tumors at 24 and 48 hr after tracer injection and only a minimal distribution in the DU 145 tumors and other organs. In contrast, the F(ab)(2) and Fab fragments of 3/A12 were detected at a high extend in the kidney but not in the C4-2 tumors. These results were confirmed by gamma counting of dissected organs after the final imaging. CONCLUSIONS Due to the high and specific uptake of the 64Cu-labeled mAbs in PSMA-positive tumors, these antibodies represent excellent tools for prostate cancer imaging.
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Affiliation(s)
- Karen Alt
- Department of Urology, University Hospital Freiburg, Freiburg, Germany
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Zieker D, Königsrainer I, Weinreich J, Beckert S, Glatzle J, Nieselt K, Bühler S, Löffler M, Gaedcke J, Northoff H, Mannheim JG, Wiehr S, Pichler BJ, von Weyhern C, Brücher BLDM, Königsrainer A. Phosphoglycerate kinase 1 promoting tumor progression and metastasis in gastric cancer - detected in a tumor mouse model using positron emission tomography/magnetic resonance imaging. Cell Physiol Biochem 2010; 26:147-54. [PMID: 20798498 DOI: 10.1159/000320545] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/05/2010] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND/AIMS Tumor dissemination is frequent in gastric cancer and implies a poor prognosis. Cure is only achievable provided an accurate staging is performed at primary diagnosis. In previous studies we were able to show a relevant impact of increased phosphoglycerate kinase 1 expression (PGK1; a glycolytic enzyme) on invasive properties of gastric cancer in-vivo and in-vitro. Thus the aim of the present study was to evaluate the effect of enhanced PGK1 expression in gastric cancer employing magnetic resonance (MR)-imaging combined with positron emission tomography (PET), a recently emerging new high resolution imaging technique in a mouse model. METHODS A metastatic nude mouse model simulating human gastric cancer behavior by orthotopic tumor implantation was established. Mice were divided into one control group (n=5) and two experimental groups (n=30) divided by half in animals baring tumors from MKN45-cells and MKN45-cells with plasmid-mediated overexpression of PGK1. In the course of tumor growth MR-imaging and PET/MRI fusion was performed. Successively experimental animals were examined macroscopically and histopathologically regarding growth, metastasis and PGK1 expression. RESULTS Elevated PGK1 expression increased invasive and metastatic behavior of implanted gastric tumors significantly. MR/PET- imaging results in-vivoand subsequent ex-vivo findings concerning tumor growth and metastasis correlated excellently and could be underlined by concordant immuohistochemical PGK1 staining. CONCLUSION Consistent in-vivo findings suggest that PGK1 might be crucially involved in gastric malignancy regarding growth and metastasis, which was also underlined by novel imaging techniques. Thus, PGK1 may be exploited as a prognostic marker and/or be of potential therapeutic value preventing malignant dissemination.
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Affiliation(s)
- Derek Zieker
- Department of General, Visceral and Transplant Surgery, Comprehensive Cancer Center, University of Tuebingen, Tuebingen, Germany.
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Wiehr S, Elsäßer-Beile U, Alt K, Bühler P, Wolf P, Judenhofer MS, Reischl G, Pichler BJ. PET Imaging of Anti-PSMA Antibodies as Novel Agents for Targeting Prostate Cancer. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1221633] [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: 10/20/2022]
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Kukuk D, Reischl G, Raguin O, Wiehr S, Cay F, Bukala D, Duchamp O, Judenhofer MS, Claussen CD, Machulla HJ, Pichler BJ. Untersuchungen zur dynamischen PET Tracer Aufnahme in hormonabhängigen Prostatatumor-Xenograft-Modellen. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1221634] [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: 10/20/2022]
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Elsässer-Beile U, Reischl G, Wiehr S, Bühler P, Wolf P, Alt K, Shively J, Judenhofer MS, Machulla HJ, Pichler BJ. PET imaging of prostate cancer xenografts with a highly specific antibody against the prostate-specific membrane antigen. J Nucl Med 2009; 50:606-11. [PMID: 19289418 DOI: 10.2967/jnumed.108.058487] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
UNLABELLED Prostate-specific membrane antigen (PSMA), a transmembrane glycoprotein, is highly expressed by virtually all prostate cancers and is currently the focus of several diagnostic and therapeutic strategies. We have previously reported on the generation of several monoclonal antibodies (mAb) and antibody fragments that recognize and bind with high affinity to the extracellular domain of cell-adherent PSMA. This article reports the in vivo behavior and tumor uptake of the radiolabeled anti-PSMA mAb 3/A12 and its potential as a tracer for PET. METHODS The mAb 3/A12 was conjugated with the chelating agent 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (DOTA) and radiolabeled with (64)Cu. Severe combined immunodeficient mice bearing PSMA-positive C4-2 prostate carcinoma xenografts were used for small-animal PET imaging. Mice with PSMA-negative DU 145 tumors served as controls. For PET studies, each animal received 20-30 microg of radiolabeled mAb corresponding to an activity of 7.6-11.5 MBq. Imaging was performed 3, 24, and 48 h after injection. After the last scan, the mice were sacrificed and tracer in vivo biodistribution was measured by gamma-counting. RESULTS Binding of the mAb 3/A12 on PSMA-expressing C4-2 cells was only minimally influenced by DOTA conjugation. The labeling efficiency using (64)Cu and DOTA-3/A12 was 95.3% +/- 0.3%. The specific activity after (64)Cu labeling was between 327 and 567 MBq/mg. After tracer injection, static small-animal PET images of mice with PSMA-positive tumors revealed a tumor-to-background ratio of 3.3 +/- 1.3 at 3 h, 7.8 +/- 1.4 at 24 h, and 9.6 +/- 2.7 at 48 h. In contrast, no significant tracer uptake occurred in the PSMA-negative DU 145 tumors. These results were confirmed by direct counting of tissues after the final imaging. CONCLUSION Because of the high and specific uptake of (64)Cu-labeled mAb 3/A12 in PSMA-positive tumors, this ligand represents an excellent candidate for prostate cancer imaging and potentially for radioimmunotherapy.
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Kukuk D, Reischl G, Raguin O, Wiehr S, Cay F, Bukala D, Duchamp O, Judenhofer J, Machulla H, Pichler B. 105 POSTER Evaluation of PET tracer uptake in mouse xenograft models of hormone-dependent prostate cancer. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)72037-8] [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: 10/21/2022] Open
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van den Brandt J, Lühder F, McPherson KG, de Graaf KL, Tischner D, Wiehr S, Herrmann T, Weissert R, Gold R, Reichardt HM. Enhanced glucocorticoid receptor signaling in T cells impacts thymocyte apoptosis and adaptive immune responses. Am J Pathol 2007; 170:1041-53. [PMID: 17322387 PMCID: PMC1864890 DOI: 10.2353/ajpath.2007.060804] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
To study the effect of enhanced glucocorticoid signaling on T cells, we generated transgenic rats overexpressing a mutant glucocorticoid receptor with increased ligand affinity in the thymus. We found that this caused massive thymocyte apoptosis at physiological hormone levels, which could be reversed by adrenalectomy. Due to homeostatic proliferation, a considerable number of mature T lymphocytes accumulated in the periphery, responding normally to costimulation but exhibiting a perturbed T-cell repertoire. Furthermore, the transgenic rats showed increased resistance to experimental autoimmune encephalomyelitis, which manifests in a delayed onset and milder disease course, impaired leukocyte infiltration into the central nervous system and a distinct cytokine profile. In contrast, the ability of the transgenic rats to mount an allergic airway response to ovalbumin was not compromised, although isotype switching of antigen-specific immunoglobulins was altered. Collectively, our findings suggest that endogenous glucocorticoids impact T-cell development and favor the selection of Th2- over Th1-dominated adaptive immune responses.
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Affiliation(s)
- Jens van den Brandt
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
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