1
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Chacko AN, Miller ADC, Dhanabalan KM, Mukherjee A. Exploring the potential of water channels for developing genetically encoded reporters and biosensors for diffusion-weighted MRI. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 365:107743. [PMID: 39053029 DOI: 10.1016/j.jmr.2024.107743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 07/02/2024] [Accepted: 07/17/2024] [Indexed: 07/27/2024]
Abstract
Genetically encoded reporters for magnetic resonance imaging (MRI) offer a valuable technology for making molecular-scale measurements of biological processes within living organisms with high anatomical resolution and whole-organ coverage without relying on ionizing radiation. However, most MRI reporters rely on synthetic contrast agents, typically paramagnetic metals and metal complexes, which often need to be supplemented exogenously to create optimal contrast. To eliminate the need for synthetic contrast agents, we previously introduced aquaporin-1, a mammalian water channel, as a new reporter gene for the fully autonomous detection of genetically labeled cells using diffusion-weighted MRI. In this study, we aimed to expand the toolbox of diffusion-based genetic reporters by modulating aquaporin membrane trafficking and harnessing the evolutionary diversity of water channels across species. We identified a number of new water channels that functioned as diffusion-weighted reporter genes. In addition, we show that loss-of-function variants of yeast and human aquaporins can be leveraged to design first-in-class diffusion-based sensors for detecting the activity of a model protease within living cells.
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Affiliation(s)
- Asish N Chacko
- Department of Chemistry, University of California, Santa Barbara, CA 93106-5080, USA
| | - Austin D C Miller
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA 93106-5080, USA
| | - Kaamini M Dhanabalan
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106-5080, USA
| | - Arnab Mukherjee
- Department of Chemistry, University of California, Santa Barbara, CA 93106-5080, USA; Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA 93106-5080, USA; Department of Chemical Engineering, University of California, Santa Barbara, CA 93106-5080, USA; Department of Bioengineering, University of California, Santa Barbara, CA 93106-5080, USA.
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2
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Calabria FF, Guadagnino G, Cimini A, Leporace M. PET/CT Imaging of Infectious Diseases: Overview of Novel Radiopharmaceuticals. Diagnostics (Basel) 2024; 14:1043. [PMID: 38786341 PMCID: PMC11120316 DOI: 10.3390/diagnostics14101043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 05/10/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024] Open
Abstract
Infectious diseases represent one of the most common causes of hospital admission worldwide. The diagnostic work-up requires a complex clinical approach, including laboratory data, CT and MRI, other imaging tools, and microbiologic cultures. PET/CT with 18F-FDG can support the clinical diagnosis, allowing visualization of increased glucose metabolism in activated macrophages and monocytes; this tracer presents limits in differentiating between aseptic inflammation and infection. Novel PET radiopharmaceuticals have been developed to overcome these limits; 11C/18F-labeled bacterial agents, several 68Ga-labeled molecules, and white blood cells labeled with 18F-FDG are emerging PET tracers under study, showing interesting preliminary results. The best choice among these tracers can be unclear. This overview aims to discuss the most common diagnostic applications of 18F-FDG PET/CT in infectious diseases and, as a counterpoint, to describe and debate the advantages and peculiarities of the latest PET radiopharmaceuticals in the field of infectious diseases, which will probably improve the diagnosis and prognostic stratification of patients with active infectious diseases.
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Affiliation(s)
- Ferdinando F. Calabria
- Department of Nuclear Medicine and Theragnostics, “Mariano Santo” Hospital, 87100 Cosenza, Italy;
| | - Giuliana Guadagnino
- Department of Infectious and Tropical Diseases, St. Annunziata Hospital, 87100 Cosenza, Italy
| | - Andrea Cimini
- Nuclear Medicine Unit, St Salvatore Hospital, 67100 L’Aquila, Italy;
| | - Mario Leporace
- Department of Nuclear Medicine and Theragnostics, “Mariano Santo” Hospital, 87100 Cosenza, Italy;
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3
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Bowden GD, Stotz S, Dunkel G, Haas S, Kimmerle E, Schaller M, Weigelin B, Herfert K, Pichler BJ, Maurer A. [ 18F] pFBC, a Covalent CLIP-Tag Radiotracer for Detection of Viral Reporter Gene Transfer in the Murine Brain. Bioconjug Chem 2024; 35:254-264. [PMID: 38308817 DOI: 10.1021/acs.bioconjchem.3c00551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2024]
Abstract
Preclinical models of neurological diseases and gene therapy are essential for neurobiological research. However, the evaluation of such models lacks reliable reporter systems for use with noninvasive imaging methods. Here, we report the development of a reporter system based on the CLIP-tag enzyme and [18F]pFBC, an 18F-labeled covalent CLIP-tag-ligand synthesized via a DoE-optimized and fully automated process. We demonstrated its specificity using a subcutaneous xenograft model and a model of viral vector-mediated brain gene transfer by engineering HEK293 cells and striatal neurons to express membrane-tethered CLIP-tag protein. After in vitro characterization of the reporter, mice carrying either CLIP-tag expressing or control subcutaneous xenografts underwent dynamic [18F]pFBC PET imaging. The CLIP-tag expressing xenografts showed a significantly higher uptake than control xenografts (tumor-to-muscle ratio 5.0 vs 1.7, p = 0.0379). In vivo, metabolite analysis by radio-HPLC from plasma and brain homogenates showed only one radio-metabolite in plasma and none in the brain. In addition, [18F]pFBC showed fast uptake and rapid clearance from the brain in animals injected with adeno-associated virus (AAV)-CLIP in the right striatum but no right-to-left (R-L) uptake difference in the striata in the acquired PET data. In contrast, autoradiography showed a clear accumulation of radioactivity in the AAV-CLIP-injected right striatum compared to the sham-injected left striatum control. CLIP-tag expression and brain integrity were verified by immunofluorescence and light sheet microscopy. In conclusion, we established a novel reporter gene system for PET imaging of gene expression in the brain and periphery and demonstrated its potential for a wide range of applications, particularly for neurobiological research and gene therapy with viral vectors.
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Affiliation(s)
- Gregory D Bowden
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tuebingen, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard Karls University, 72076 Tuebingen, Germany
| | - Sophie Stotz
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tuebingen, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard Karls University, 72076 Tuebingen, Germany
| | - Gina Dunkel
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tuebingen, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard Karls University, 72076 Tuebingen, Germany
| | - Sabrina Haas
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tuebingen, Germany
| | - Elena Kimmerle
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tuebingen, Germany
| | - Martin Schaller
- Department of Dermatology, University Hospital Tuebingen, 72076 Tuebingen, Germany
| | - Bettina Weigelin
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tuebingen, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard Karls University, 72076 Tuebingen, Germany
| | - Kristina Herfert
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tuebingen, Germany
| | - Bernd J Pichler
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tuebingen, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard Karls University, 72076 Tuebingen, Germany
| | - Andreas Maurer
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tuebingen, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard Karls University, 72076 Tuebingen, Germany
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4
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Burban A, Słupik D, Reda A, Szczerba E, Grabowski M, Kołodzińska A. Novel Diagnostic Methods for Infective Endocarditis. Int J Mol Sci 2024; 25:1245. [PMID: 38279244 PMCID: PMC10816594 DOI: 10.3390/ijms25021245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/14/2024] [Accepted: 01/15/2024] [Indexed: 01/28/2024] Open
Abstract
Infective endocarditis (IE) remains a dangerous disease and continues to have a high mortality rate. Unfortunately, despite continuous improvements in diagnostic methods, in many cases, blood cultures remain negative, and the pathogen causing endocarditis is unknown. This makes targeted therapy and the selection of appropriate antibiotics impossible. Therefore, we present what methods can be used to identify the pathogen in infective endocarditis. These are mainly molecular methods, including PCR and MGS, as well as imaging methods using radiotracers, which offer more possibilities for diagnosing IE. However, they are still not widely used in the diagnosis of IE. The article summarizes in which cases we should choose them and what we are most hopeful about in further research into the diagnosis of IE. In addition, registered clinical trials that are currently underway for the diagnosis of IE are also presented.
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Affiliation(s)
- Anna Burban
- 1st Chair and Department of Cardiology, Medical University of Warsaw, 02-097 Warsaw, Poland
- Doctoral School, Medical University of Warsaw, 02-091 Warsaw, Poland
| | - Dorota Słupik
- 1st Chair and Department of Cardiology, Medical University of Warsaw, 02-097 Warsaw, Poland
| | - Aleksandra Reda
- 1st Chair and Department of Cardiology, Medical University of Warsaw, 02-097 Warsaw, Poland
| | - Ewa Szczerba
- 1st Chair and Department of Cardiology, Medical University of Warsaw, 02-097 Warsaw, Poland
| | - Marcin Grabowski
- 1st Chair and Department of Cardiology, Medical University of Warsaw, 02-097 Warsaw, Poland
| | - Agnieszka Kołodzińska
- 1st Chair and Department of Cardiology, Medical University of Warsaw, 02-097 Warsaw, Poland
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5
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Etersque JM, Lee IK, Sharma N, Xu K, Ruff A, Northrup JD, Sarkar S, Nguyen T, Lauman R, Burslem GM, Sellmyer MA. Regulation of eDHFR-tagged proteins with trimethoprim PROTACs. Nat Commun 2023; 14:7071. [PMID: 37923771 PMCID: PMC10624689 DOI: 10.1038/s41467-023-42820-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 10/22/2023] [Indexed: 11/06/2023] Open
Abstract
Temporal control of protein levels in cells and living animals can be used to improve our understanding of protein function. In addition, control of engineered proteins could be used in therapeutic applications. PRoteolysis-TArgeting Chimeras (PROTACs) have emerged as a small-molecule-driven strategy to achieve rapid, post-translational regulation of protein abundance via recruitment of an E3 ligase to the target protein of interest. Here, we develop several PROTAC molecules by covalently linking the antibiotic trimethoprim (TMP) to pomalidomide, a ligand for the E3 ligase, Cereblon. These molecules induce degradation of proteins of interest (POIs) genetically fused to a small protein domain, E. coli dihydrofolate reductase (eDHFR), the molecular target of TMP. We show that various eDHFR-tagged proteins can be robustly degraded to 95% of maximum expression with PROTAC molecule 7c. Moreover, TMP-based PROTACs minimally affect the expression of immunomodulatory imide drug (IMiD)-sensitive neosubstrates using proteomic and biochemical assays. Finally, we show multiplexed regulation with another known degron-PROTAC pair, as well as reversible protein regulation in a rodent model of metastatic cancer, demonstrating the formidable strength of this system. Altogether, TMP PROTACs are a robust approach for selective and reversible degradation of eDHFR-tagged proteins in vitro and in vivo.
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Affiliation(s)
- Jean M Etersque
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Iris K Lee
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nitika Sharma
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kexiang Xu
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Andrew Ruff
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Justin D Northrup
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Swarbhanu Sarkar
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Tommy Nguyen
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Richard Lauman
- The Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - George M Burslem
- The Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- The Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Mark A Sellmyer
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- The Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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6
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Kleynhans J, Sathekge MM, Ebenhan T. Preclinical Research Highlighting Contemporary Targeting Mechanisms of Radiolabelled Compounds for PET Based Infection Imaging. Semin Nucl Med 2023; 53:630-643. [PMID: 37012169 DOI: 10.1053/j.semnuclmed.2023.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 03/07/2023] [Indexed: 04/04/2023]
Abstract
It is important to constantly monitor developments in the preclinical imaging arena of infection. Firstly, novel radiopharmaceuticals with the correct characteristics must be identified to funnel into the clinic. Secondly, it must be evaluated if enough innovative research is being done and adequate resources are geared towards the development of radiopharmaceuticals that could feed into the Nuclear Medicine Clinic in the near future. It is proposed that the ideal infection imaging agent will involve PET combined with CT but more ideally MRI. The radiopharmaceuticals currently presented in preclinical literature have a wide selection of vectors and targets. Ionic formulations of PET-radionuclides such 64CuCl2 and 68GaCl2 are evaluated for bacterial infection imaging. Many small molecule based radiopharmaceuticals are being investigated with the most prominent targets being cell wall synthesis, maltodextrin transport (such as [18F]F-maltotriose), siderophores (bacterial and fungal infections), the folate synthesis pathway (such as [18F]F-PABA) and protein synthesis (radiolabelled puromycin). Mycobacterial specific antibiotics, antifungals and antiviral agents are also under investigation as infection imaging agents. Peptide based radiopharmaceuticals are developed for bacterial, fungal and viral infections. The radiopharmaceutical development could even react quickly enough on a pandemic to develop a SARS-CoV-2 imaging agent in a timely fashion ([64Cu]Cu-NOTA-EK1). New immuno-PET agents for the imaging of viruses have recently been published, specifically for HIV persistence but also for SARS-CoV2. A very promising antifungal immuno-PET agent (hJ5F) is also considered. Future technologies could include the application of aptamers and bacteriophages and even going as far as the design of theranostic infection. Another possibility would be the application of nanobodies for immuno-PET applications. Standardization and optimization of the preclinical evaluation of radiopharmaceuticals could enhance clinical translation and reduce time spent in pursuing less than optimal candidates.
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Affiliation(s)
- Janke Kleynhans
- Department of Pharmaceutical and Pharmacological sciences, Radiopharmaceutical Research, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Mike Machaba Sathekge
- Department of Nuclear Medicine, University of Pretoria and Steve Biko Academic Hospital, Pretoria, South Africa; Preclinical Imaging Facility, Nuclear Medicine Research Infrastructure, Pretoria, South Africa
| | - Thomas Ebenhan
- Preclinical Imaging Facility, Nuclear Medicine Research Infrastructure, Pretoria, South Africa; Department of Nuclear Medicine, University of Pretoria, Pretoria, South Africa.
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7
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Gouws AC, Kruger HG, Gheysens O, Zeevaart JR, Govender T, Naicker T, Ebenhan T. Antibiotic-Derived Radiotracers for Positron Emission Tomography: Nuclear or "Unclear" Infection Imaging? Angew Chem Int Ed Engl 2022; 61:e202204955. [PMID: 35834311 PMCID: PMC9826354 DOI: 10.1002/anie.202204955] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Indexed: 01/11/2023]
Abstract
The excellent features of non-invasive molecular imaging, its progressive technology (real-time, whole-body imaging and quantification), and global impact by a growing infrastructure for positron emission tomography (PET) scanners are encouraging prospects to investigate new concepts, which could transform clinical care of complex infectious diseases. Researchers are aiming towards the extension beyond the routinely available radiopharmaceuticals and are looking for more effective tools that interact directly with causative pathogens. We reviewed and critically evaluated (challenges or pitfalls) antibiotic-derived PET radiopharmaceutical development efforts aimed at infection imaging. We considered both radiotracer development for infection imaging and radio-antibiotic PET imaging supplementing other tools for pharmacologic drug characterization; overall, a total of 20 original PET radiotracers derived from eleven approved antibiotics.
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Affiliation(s)
- Arno Christiaan Gouws
- Catalysis and Peptide Research UnitUniversity of KwaZulu-NatalDurban4000South Africa
| | | | - Olivier Gheysens
- Department of Nuclear MedicineCliniques Universitaires Saint-Luc, and Institute of Clinical and Experimental ResearchUniversité Catholique de LouvainBrusselsBelgium
| | - Jan Rijn Zeevaart
- Nuclear Medicine Research Infrastructure NPCPretoria0001South Africa
- RadiochemistryThe South African Nuclear Energy CorporationBrits0420South Africa
- Preclinical Drug Development PlatformNorth West UniversityPotchefstroom2520South Africa
| | | | - Tricia Naicker
- Catalysis and Peptide Research UnitUniversity of KwaZulu-NatalDurban4000South Africa
| | - Thomas Ebenhan
- Nuclear Medicine Research Infrastructure NPCPretoria0001South Africa
- Preclinical Drug Development PlatformNorth West UniversityPotchefstroom2520South Africa
- Department of Nuclear MedicineUniversity of PretoriaPretoria0001South Africa
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8
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Lee IK, Jacome DA, Cho JK, Tu V, Young AJ, Dominguez T, Northrup JD, Etersque JM, Lee HS, Ruff A, Aklilu O, Bittinger K, Glaser LJ, Dorgan D, Hadjiliadis D, Kohli RM, Mach RH, Mankoff DA, Doot RK, Sellmyer MA. Imaging sensitive and drug-resistant bacterial infection with [11C]-trimethoprim. J Clin Invest 2022; 132:156679. [PMID: 36106638 PMCID: PMC9479701 DOI: 10.1172/jci156679] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 07/19/2022] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Several molecular imaging strategies can identify bacterial infections in humans. PET affords the potential for sensitive infection detection deep within the body. Among PET-based approaches, antibiotic-based radiotracers, which often target key bacterial-specific enzymes, have considerable promise. One question for antibiotic radiotracers is whether antimicrobial resistance (AMR) reduces specific accumulation within bacteria, diminishing the predictive value of the diagnostic test. METHODS Using a PET radiotracer based on the antibiotic trimethoprim (TMP), [11C]-TMP, we performed in vitro uptake studies in susceptible and drug-resistant bacterial strains and whole-genome sequencing (WGS) in selected strains to identify TMP resistance mechanisms. Next, we queried the NCBI database of annotated bacterial genomes for WT and resistant dihydrofolate reductase (DHFR) genes. Finally, we initiated a first-in-human protocol of [11C]-TMP in patients infected with both TMP-sensitive and TMP-resistant organisms to demonstrate the clinical feasibility of the tool. RESULTS We observed robust [11C]-TMP uptake in our panel of TMP-sensitive and -resistant bacteria, noting relatively variable and decreased uptake in a few strains of P. aeruginosa and E. coli. WGS showed that the vast majority of clinically relevant bacteria harbor a WT copy of DHFR, targetable by [11C]-TMP, and that despite the AMR, these strains should be “imageable.” Clinical imaging of patients with [11C]-TMP demonstrated focal radiotracer uptake in areas of infectious lesions. CONCLUSION This work highlights an approach to imaging bacterial infection in patients, which could affect our understanding of bacterial pathogenesis as well as our ability to better diagnose infections and monitor response to therapy. TRIAL REGISTRATION ClinicalTrials.gov NCT03424525. FUNDING Institute for Translational Medicine and Therapeutics, Burroughs Wellcome Fund, NIH Office of the Director Early Independence Award (DP5-OD26386), and University of Pennsylvania NIH T32 Radiology Research Training Grant (5T32EB004311-12).
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Affiliation(s)
- Iris K. Lee
- Department of Radiology and
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | | | - Vincent Tu
- Department of Gastroenterology, Hepatology and Nutrition, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | | | | | | | - Jean M. Etersque
- Department of Radiology and
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | | | | | - Kyle Bittinger
- Department of Gastroenterology, Hepatology and Nutrition, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Laurel J. Glaser
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Daniel Dorgan
- Department of Medicine, Division of Allergy, Pulmonary, and Critical Care Medicine, and
| | - Denis Hadjiliadis
- Department of Medicine, Division of Allergy, Pulmonary, and Critical Care Medicine, and
| | - Rahul M. Kohli
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Medicine, Division of Infectious Disease, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | | | | | - Mark A. Sellmyer
- Department of Radiology and
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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9
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Co CM, Mulgaonkar A, Zhou N, Harris S, Öz OK, Tang L, Sun X. PET Imaging of Active Invasive Fungal Infections with d-[5- 11C]-Glutamine. ACS Infect Dis 2022; 8:1663-1673. [PMID: 35869564 DOI: 10.1021/acsinfecdis.2c00249] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The increasing prevalence and severity of invasive fungal infections (IFIs), especially in immunocompromised populations, has amplified the need for rapid diagnosis of fungal pathogens. Radiotracers derived from d-amino acids (DAAs) show promise as bacterial-specific positron emission tomography (PET) imaging agents due to their preferential consumption by bacteria and largely nonutilization by hosts. Unlike mammals, fungi can utilize external DAAs including d-glutamine for their growth by rapidly upregulating DAA oxidases. Additionally, glutamine is essential for fungal nitrogen assimilation, survival, and virulence. We previously validated d-[5-11C]-glutamine (d-[5-11C]-Gln) as an efficient radiotracer targeting live bacterial soft-tissue infections. Here, we further expanded this investigation to evaluate its translational potential for PET imaging of IFIs in immunocompetent mouse models subcutaneously (SubQ) and intramuscularly (IM) infected with Candida albicans (C. albicans), using its l-isomer counterpart (l-[5-11C]-Gln) as a control. Comparative studies between pathogens showed significantly (p < 0.05) higher uptake in fungi (C. albicans and C. tropicalis) versus tested bacterial species for d-[5-11C]-Gln, suggesting that it could potentially serve as a more sensitive radiotracer for detection of fungal infections. Additionally, comparative PET imaging studies in immunocompetent infected mice demonstrated significantly higher infection-to-background ratios for d- versus l-[5-11C]-Gln in both SubQ (ratio = 1.97, p = 0.043) and IM (ratio = 1.97, p = 0.028) infections. Fungal infection imaging specificity was confirmed with no significant difference observed between localized inflammation sites versus untreated muscle background (heat-killed injection site/untreated muscle: ∼1.1). Taken together, this work demonstrates the translational potential of d-[5-11C]-Gln for noninvasive PET imaging of IFIs.
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Affiliation(s)
- Cynthia M Co
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas 76019, United States
| | - Aditi Mulgaonkar
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Ning Zhou
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Shelby Harris
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Orhan K Öz
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Liping Tang
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas 76019, United States
| | - Xiankai Sun
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
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10
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Gouws AC, Kruger HG, Gheysens O, Zeevaart JR, Govender T, Naiker T, Ebenhan T. Antibiotic‐Derived Radiotracers for Positron Emission Tomography: Nuclear or ‘Unclear’ Infection Imaging? Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Arno Christiaan Gouws
- University of KwaZulu-Natal School of Health Sciences Catalysis and Peptide Research Unit SOUTH AFRICA
| | - Hendrik Gerhardus Kruger
- University of KwaZulu-Natal School of Health Sciences Catalysis and Peptide Research Unit SOUTH AFRICA
| | - Olivier Gheysens
- Cliniques Universitaires Saint-Luc Department of Nuclear Medicine BELGIUM
| | - Jan Rijn Zeevaart
- North-West University Potchefstroom Campus: North-West University Preclinical Drug Development Platform SOUTH AFRICA
| | | | - Tricia Naiker
- University of KwaZulu-Natal School of Health Sciences Catalysis and Peptide Research Unit SOUTH AFRICA
| | - Thomas Ebenhan
- University of Pretoria Nuclear Medicine Steve Biko and Malherbe St 0001 Pretoria SOUTH AFRICA
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11
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Lauwerys L, Smits E, Van den Wyngaert T, Elvas F. Radionuclide Imaging of Cytotoxic Immune Cell Responses to Anti-Cancer Immunotherapy. Biomedicines 2022; 10:biomedicines10051074. [PMID: 35625811 PMCID: PMC9139020 DOI: 10.3390/biomedicines10051074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 04/24/2022] [Accepted: 04/30/2022] [Indexed: 11/16/2022] Open
Abstract
Cancer immunotherapy is an evolving and promising cancer treatment that takes advantage of the body’s immune system to yield effective tumor elimination. Importantly, immunotherapy has changed the treatment landscape for many cancers, resulting in remarkable tumor responses and improvements in patient survival. However, despite impressive tumor effects and extended patient survival, only a small proportion of patients respond, and others can develop immune-related adverse events associated with these therapies, which are associated with considerable costs. Therefore, strategies to increase the proportion of patients gaining a benefit from these treatments and/or increasing the durability of immune-mediated tumor response are still urgently needed. Currently, measurement of blood or tissue biomarkers has demonstrated sampling limitations, due to intrinsic tumor heterogeneity and the latter being invasive. In addition, the unique response patterns of these therapies are not adequately captured by conventional imaging modalities. Consequently, non-invasive, sensitive, and quantitative molecular imaging techniques, such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) using specific radiotracers, have been increasingly used for longitudinal whole-body monitoring of immune responses. Immunotherapies rely on the effector function of CD8+ T cells and natural killer cells (NK) at tumor lesions; therefore, the monitoring of these cytotoxic immune cells is of value for therapy response assessment. Different immune cell targets have been investigated as surrogate markers of response to immunotherapy, which motivated the development of multiple imaging agents. In this review, the targets and radiotracers being investigated for monitoring the functional status of immune effector cells are summarized, and their use for imaging of immune-related responses are reviewed along their limitations and pitfalls, of which multiple have already been translated to the clinic. Finally, emerging effector immune cell imaging strategies and future directions are provided.
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Affiliation(s)
- Louis Lauwerys
- Molecular Imaging Center Antwerp (MICA), Integrated Personalized and Precision Oncology Network (IPPON), Faculty of Medicine and Health Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium; (L.L.); (T.V.d.W.)
| | - Evelien Smits
- Center for Oncological Research (CORE), Integrated Personalized and Precision Oncology Network (IPPON), Faculty of Medicine and Health Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium;
- Center for Cell Therapy and Regenerative Medicine, Antwerp University Hospital, Drie Eikenstraat 655, B-2650 Edegem, Belgium
| | - Tim Van den Wyngaert
- Molecular Imaging Center Antwerp (MICA), Integrated Personalized and Precision Oncology Network (IPPON), Faculty of Medicine and Health Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium; (L.L.); (T.V.d.W.)
- Nuclear Medicine, Antwerp University Hospital, Drie Eikenstraat 655, B-2650 Edegem, Belgium
| | - Filipe Elvas
- Molecular Imaging Center Antwerp (MICA), Integrated Personalized and Precision Oncology Network (IPPON), Faculty of Medicine and Health Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium; (L.L.); (T.V.d.W.)
- Correspondence:
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Crișan G, Moldovean-Cioroianu NS, Timaru DG, Andrieș G, Căinap C, Chiș V. Radiopharmaceuticals for PET and SPECT Imaging: A Literature Review over the Last Decade. Int J Mol Sci 2022; 23:ijms23095023. [PMID: 35563414 PMCID: PMC9103893 DOI: 10.3390/ijms23095023] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 04/23/2022] [Accepted: 04/28/2022] [Indexed: 02/04/2023] Open
Abstract
Positron emission tomography (PET) uses radioactive tracers and enables the functional imaging of several metabolic processes, blood flow measurements, regional chemical composition, and/or chemical absorption. Depending on the targeted processes within the living organism, different tracers are used for various medical conditions, such as cancer, particular brain pathologies, cardiac events, and bone lesions, where the most commonly used tracers are radiolabeled with 18F (e.g., [18F]-FDG and NA [18F]). Oxygen-15 isotope is mostly involved in blood flow measurements, whereas a wide array of 11C-based compounds have also been developed for neuronal disorders according to the affected neuroreceptors, prostate cancer, and lung carcinomas. In contrast, the single-photon emission computed tomography (SPECT) technique uses gamma-emitting radioisotopes and can be used to diagnose strokes, seizures, bone illnesses, and infections by gauging the blood flow and radio distribution within tissues and organs. The radioisotopes typically used in SPECT imaging are iodine-123, technetium-99m, xenon-133, thallium-201, and indium-111. This systematic review article aims to clarify and disseminate the available scientific literature focused on PET/SPECT radiotracers and to provide an overview of the conducted research within the past decade, with an additional focus on the novel radiopharmaceuticals developed for medical imaging.
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Affiliation(s)
- George Crișan
- Faculty of Physics, Babeş-Bolyai University, Str. M. Kogălniceanu 1, 400084 Cluj-Napoca, Romania; (G.C.); (N.S.M.-C.); (D.-G.T.)
- Department of Nuclear Medicine, County Clinical Hospital, Clinicilor 3-5, 400006 Cluj-Napoca, Romania;
| | | | - Diana-Gabriela Timaru
- Faculty of Physics, Babeş-Bolyai University, Str. M. Kogălniceanu 1, 400084 Cluj-Napoca, Romania; (G.C.); (N.S.M.-C.); (D.-G.T.)
| | - Gabriel Andrieș
- Department of Nuclear Medicine, County Clinical Hospital, Clinicilor 3-5, 400006 Cluj-Napoca, Romania;
| | - Călin Căinap
- The Oncology Institute “Prof. Dr. Ion Chiricuţă”, Republicii 34-36, 400015 Cluj-Napoca, Romania;
| | - Vasile Chiș
- Faculty of Physics, Babeş-Bolyai University, Str. M. Kogălniceanu 1, 400084 Cluj-Napoca, Romania; (G.C.); (N.S.M.-C.); (D.-G.T.)
- Institute for Research, Development and Innovation in Applied Natural Sciences, Babeș-Bolyai University, Str. Fântânele 30, 400327 Cluj-Napoca, Romania
- Correspondence:
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Nerella SG, Singh P, Sanam T, Digwal CS. PET Molecular Imaging in Drug Development: The Imaging and Chemistry Perspective. Front Med (Lausanne) 2022; 9:812270. [PMID: 35295604 PMCID: PMC8919964 DOI: 10.3389/fmed.2022.812270] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 01/18/2022] [Indexed: 11/13/2022] Open
Abstract
Positron emission tomography with selective radioligands advances the drug discovery and development process by revealing information about target engagement, proof of mechanism, pharmacokinetic and pharmacodynamic profiles. Positron emission tomography (PET) is an essential and highly significant tool to study therapeutic drug development, dose regimen, and the drug plasma concentrations of new drug candidates. Selective radioligands bring up target-specific information in several disease states including cancer, cardiovascular, and neurological conditions by quantifying various rates of biological processes with PET, which are associated with its physiological changes in living subjects, thus it reveals disease progression and also advances the clinical investigation. This study explores the major roles, applications, and advances of PET molecular imaging in drug discovery and development process with a wide range of radiochemistry as well as clinical outcomes of positron-emitting carbon-11 and fluorine-18 radiotracers.
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Affiliation(s)
- Sridhar Goud Nerella
- Department of Neuroimaging and Interventional Radiology, National Institute of Mental Health and Neurosciences, Bengaluru, India
| | - Priti Singh
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Hyderabad, India
| | - Tulja Sanam
- Department of Microbiology and Applied Sciences, University of Agricultural Sciences, Bangalore, India
| | - Chander Singh Digwal
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Hyderabad, India
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Shimojo M, Ono M, Takuwa H, Mimura K, Nagai Y, Fujinaga M, Kikuchi T, Okada M, Seki C, Tokunaga M, Maeda J, Takado Y, Takahashi M, Minamihisamatsu T, Zhang M, Tomita Y, Suzuki N, Maximov A, Suhara T, Minamimoto T, Sahara N, Higuchi M. A genetically targeted reporter for PET imaging of deep neuronal circuits in mammalian brains. EMBO J 2021; 40:e107757. [PMID: 34636430 PMCID: PMC8591537 DOI: 10.15252/embj.2021107757] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 08/24/2021] [Accepted: 08/31/2021] [Indexed: 01/27/2023] Open
Abstract
Positron emission tomography (PET) allows biomolecular tracking but PET monitoring of brain networks has been hampered by a lack of suitable reporters. Here, we take advantage of bacterial dihydrofolate reductase, ecDHFR, and its unique antagonist, TMP, to facilitate in vivo imaging in the brain. Peripheral administration of radiofluorinated and fluorescent TMP analogs enabled PET and intravital microscopy, respectively, of neuronal ecDHFR expression in mice. This technique can be used to the visualize neuronal circuit activity elicited by chemogenetic manipulation in the mouse hippocampus. Notably, ecDHFR-PET allows mapping of neuronal projections in non-human primate brains, demonstrating the applicability of ecDHFR-based tracking technologies for network monitoring. Finally, we demonstrate the utility of TMP analogs for PET studies of turnover and self-assembly of proteins tagged with ecDHFR mutants. These results establish opportunities for a broad spectrum of previously unattainable PET analyses of mammalian brain circuits at the molecular level.
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Affiliation(s)
- Masafumi Shimojo
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Maiko Ono
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Hiroyuki Takuwa
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Koki Mimura
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Yuji Nagai
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Masayuki Fujinaga
- Department of Radiopharmaceuticals DevelopmentNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Tatsuya Kikuchi
- Department of Radiopharmaceuticals DevelopmentNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Maki Okada
- Department of Radiopharmaceuticals DevelopmentNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Chie Seki
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Masaki Tokunaga
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Jun Maeda
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Yuhei Takado
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Manami Takahashi
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Takeharu Minamihisamatsu
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Ming‐Rong Zhang
- Department of Radiopharmaceuticals DevelopmentNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Yutaka Tomita
- Department of NeurologyKeio University School of MedicineTokyoJapan
| | - Norihiro Suzuki
- Department of NeurologyKeio University School of MedicineTokyoJapan
| | - Anton Maximov
- Department of NeuroscienceThe Scripps Research InstituteLa JollaCAUSA
| | - Tetsuya Suhara
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Takafumi Minamimoto
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Naruhiko Sahara
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Makoto Higuchi
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
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15
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Covalent 18F-Radiotracers for SNAPTag: A New Toolbox for Reporter Gene Imaging. Pharmaceuticals (Basel) 2021; 14:ph14090897. [PMID: 34577597 PMCID: PMC8466261 DOI: 10.3390/ph14090897] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 08/30/2021] [Accepted: 09/01/2021] [Indexed: 11/26/2022] Open
Abstract
There is a need for versatile in vivo nuclear imaging reporter systems to foster preclinical and clinical research. We explore the applicability of the SNAPTag and novel radiolabeled small-molecule ligands as a versatile reporter gene system for in vivo nuclear imaging. SNAPTag is a high-affinity protein tag used in a variety of biochemical research areas and based on the suicide DNA repair enzyme O6-methylguanine methyl transferase (MGMT). Its ligands are well suited for reporter gene imaging as the benzyl guanine core scaffold can be derivatized with fluorescent or radiolabeled moieties for various applications. Three guanine-based SNAPTag ligands ([18F]FBBG, [18F]pFBG and [18F]mFBG) were synthesized in high yields and were (radio)chemically characterized. HEK293 cells were engineered to express the SNAPTag on the cell surface and served as cell model to assess target affinity by radiotracer uptake assays, Western blotting and SDS-PAGE autoradiography. A subcutaneous HEK293-SNAPTag xenograft model in immunodeficient mice was used for in vivo evaluation of [18F]FBBG and [18F]pFBG while the biodistribution of [18F]mFBG was characterized in naïve animals. The results were validated by ex vivo biodistribution studies and immunofluorescence staining of the xenografts. All three radiotracers were produced in high radiochemical purity, molar activity and good yields. Western blot analysis revealed successful SNAPTag expression by the transfected HEK293 cells. In vitro testing revealed high target affinity of all three tracers with an up to 191-fold higher signal in the HEK293-SNAPTag cells compared to untransfected cells. This was further supported by a prominent radioactive protein band at the expected size in the SDS-PAGE autoradiograph of cells incubated with [18F]FBBG or [18F]pFBG. The in vivo studies demonstrated high uptake in HEK293-SNAP xenografts compared to HEK293 xenografts with excellent tumor-to-muscle ratios (7.5 ± 4.2 for [18F]FBBG and 10.6 ± 6.2 for [18F]pFBG). In contrast to [18F]pFBG and its chemical analogue [18F]mFBG, [18F]FBBG showed no signs of unspecific bone uptake and defluorination in vivo. Radiolabeled SNAPTag ligands bear great potential for clinical applications such as in vivo tracking of cell populations, antibody fragments and targeted radiotherapy. With excellent target affinity, good stability, and low non-specific binding, [18F]FBBG is a highly promising candidate for further preclinical evaluation.
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Lechermann LM, Lau D, Attili B, Aloj L, Gallagher FA. In Vivo Cell Tracking Using PET: Opportunities and Challenges for Clinical Translation in Oncology. Cancers (Basel) 2021; 13:4042. [PMID: 34439195 PMCID: PMC8392745 DOI: 10.3390/cancers13164042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 12/21/2022] Open
Abstract
Cell therapy is a rapidly evolving field involving a wide spectrum of therapeutic cells for personalised medicine in cancer. In vivo imaging and tracking of cells can provide useful information for improving the accuracy, efficacy, and safety of cell therapies. This review focuses on radiopharmaceuticals for the non-invasive detection and tracking of therapeutic cells using positron emission tomography (PET). A range of approaches for imaging therapeutic cells is discussed: Direct ex vivo labelling of cells, in vivo indirect labelling of cells by utilising gene reporters, and detection of specific antigens expressed on the target cells using antibody-based radiopharmaceuticals (immuno-PET). This review examines the evaluation of PET imaging methods for therapeutic cell tracking in preclinical cancer models, their role in the translation into patients, first-in-human studies, as well as the translational challenges involved and how they can be overcome.
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Affiliation(s)
- Laura M. Lechermann
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, UK; (B.A.); (L.A.); (F.A.G.)
- Cancer Research UK Cambridge Centre, Cambridge CB2 0RE, UK
| | - Doreen Lau
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, UK; (B.A.); (L.A.); (F.A.G.)
- Cancer Research UK Cambridge Centre, Cambridge CB2 0RE, UK
| | - Bala Attili
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, UK; (B.A.); (L.A.); (F.A.G.)
- Cancer Research UK Cambridge Centre, Cambridge CB2 0RE, UK
| | - Luigi Aloj
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, UK; (B.A.); (L.A.); (F.A.G.)
- Cancer Research UK Cambridge Centre, Cambridge CB2 0RE, UK
- Department of Nuclear Medicine, Addenbrooke’s Hospital, Cambridge CB2 0QQ, UK
| | - Ferdia A. Gallagher
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, UK; (B.A.); (L.A.); (F.A.G.)
- Cancer Research UK Cambridge Centre, Cambridge CB2 0RE, UK
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Shao F, Long Y, Ji H, Jiang D, Lei P, Lan X. Radionuclide-based molecular imaging allows CAR-T cellular visualization and therapeutic monitoring. Am J Cancer Res 2021; 11:6800-6817. [PMID: 34093854 PMCID: PMC8171102 DOI: 10.7150/thno.56989] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 04/20/2021] [Indexed: 02/07/2023] Open
Abstract
Chimeric antigen receptor T cell (CAR-T) therapy is a new and effective form of adoptive cell therapy that is rapidly entering the mainstream for the treatment of CD19-positive hematological cancers because of its impressive effect and durable responses. Huge challenges remain in achieving similar success in patients with solid tumors. The current methods of monitoring CAR-T, including morphological imaging (CT and MRI), blood tests, and biopsy, have limitations to assess whether CAR-T cells are homing to tumor sites and infiltrating into tumor bed, or to assess the survival, proliferation, and persistence of CAR-T cells in solid tumors associated with an immunosuppressive microenvironment. Radionuclide-based molecular imaging affords improved CAR-T cellular visualization and therapeutic monitoring through either a direct cellular radiolabeling approach or a reporter gene imaging strategy, and endogenous cell imaging is beneficial to reflect functional information and immune status of T cells. Focusing on the dynamic monitoring and precise assessment of CAR-T therapy, this review summarizes the current applications of radionuclide-based noninvasive imaging in CAR-T cells visualization and monitoring and presents current challenges and strategic choices.
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Abstract
Positron emission tomography (PET) is a non-invasive imaging technology employed to describe metabolic, physiological, and biochemical processes in vivo. These include receptor availability, metabolic changes, neurotransmitter release, and alterations of gene expression in the brain. Since the introduction of dedicated small-animal PET systems along with the development of many novel PET imaging probes, the number of PET studies using rats and mice in basic biomedical research tremendously increased over the last decade. This article reviews challenges and advances of quantitative rodent brain imaging to make the readers aware of its physical limitations, as well as to inspire them for its potential applications in preclinical research. In the first section, we briefly discuss the limitations of small-animal PET systems in terms of spatial resolution and sensitivity and point to possible improvements in detector development. In addition, different acquisition and post-processing methods used in rodent PET studies are summarized. We further discuss factors influencing the test-retest variability in small-animal PET studies, e.g., different receptor quantification methodologies which have been mainly translated from human to rodent receptor studies to determine the binding potential and changes of receptor availability and radioligand affinity. We further review different kinetic modeling approaches to obtain quantitative binding data in rodents and PET studies focusing on the quantification of endogenous neurotransmitter release using pharmacological interventions. While several studies have focused on the dopamine system due to the availability of several PET tracers which are sensitive to dopamine release, other neurotransmitter systems have become more and more into focus and are described in this review, as well. We further provide an overview of latest genome engineering technologies, including the CRISPR/Cas9 and DREADD systems that may advance our understanding of brain disorders and function and how imaging has been successfully applied to animal models of human brain disorders. Finally, we review the strengths and opportunities of simultaneous PET/magnetic resonance imaging systems to study drug-receptor interactions and challenges for the translation of PET results from bench to bedside.
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Renick PJ, Mulgaonkar A, Co CM, Wu CY, Zhou N, Velazquez A, Pennington J, Sherwood A, Dong H, Castellino L, Öz OK, Tang L, Sun X. Imaging of Actively Proliferating Bacterial Infections by Targeting the Bacterial Metabolic Footprint with d-[5- 11C]-Glutamine. ACS Infect Dis 2021; 7:347-361. [PMID: 33476123 DOI: 10.1021/acsinfecdis.0c00617] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Since most d-amino acids (DAAs) are utilized by bacterial cells but not by mammalian eukaryotic hosts, recently DAA-based molecular imaging strategies have been extensively explored for noninvasively differentiating bacterial infections from the host's inflammatory responses. Given glutamine's pivotal role in bacterial survival, cell growth, biofilm formation, and even virulence, here we report a new positron emission tomography (PET) imaging approach using d-5-[11C]glutamine (d-[5-11C]-Gln) for potential clinical assessment of bacterial infection through a comparative study with its l-isomer counterpart, l-[5-11C]-Gln. In both control and infected mice, l-[5-11C]-Gln had substantially higher uptake levels than d-[5-11C]-Gln in most organs except the kidneys, showing the expected higher use of l-[5-11C]-Gln by mammalian tissues and more efficient renal excretion of d-[5-11C]-Gln. Importantly, our work demonstrates that PET imaging with d-[5-11C]-Gln is capable of detecting infections induced by both Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA) in a dual-infection murine myositis model with significantly higher infection-to-background contrast than with l-[5-11C]-Gln (in E. coli, 1.64; in MRSA, 2.62, p = 0.0004). This can be attributed to the fact that d-[5-11C]-Gln is utilized by bacteria while being more efficiently cleared from the host tissues. We confirmed the bacterial infection imaging specificity of d-[5-11C]-Gln by comparing its uptake in active bacterial infections versus sterile inflammation and with 2-deoxy-2-[18F]fluoroglucose ([18F]FDG). These results together demonstrate the translational potential of PET imaging with d-[5-11C]-Gln for the noninvasive detection of bacterial infectious diseases in humans.
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Goud NS, Bhattacharya A, Joshi RK, Nagaraj C, Bharath RD, Kumar P. Carbon-11: Radiochemistry and Target-Based PET Molecular Imaging Applications in Oncology, Cardiology, and Neurology. J Med Chem 2021; 64:1223-1259. [PMID: 33499603 DOI: 10.1021/acs.jmedchem.0c01053] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The positron emission tomography (PET) molecular imaging technique has gained its universal value as a remarkable tool for medical diagnosis and biomedical research. Carbon-11 is one of the promising radiotracers that can report target-specific information related to its pharmacology and physiology to understand the disease status. Currently, many of the available carbon-11 (t1/2 = 20.4 min) PET radiotracers are heterocyclic derivatives that have been synthesized using carbon-11 inserted different functional groups obtained from primary and secondary carbon-11 precursors. A spectrum of carbon-11 PET radiotracers has been developed against many of the upregulated and emerging targets for the diagnosis, prognosis, prediction, and therapy in the fields of oncology, cardiology, and neurology. This review focuses on the carbon-11 radiochemistry and various target-specific PET molecular imaging agents used in tumor, heart, brain, and neuroinflammatory disease imaging along with its associated pathology.
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Affiliation(s)
- Nerella Sridhar Goud
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Ahana Bhattacharya
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Raman Kumar Joshi
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Chandana Nagaraj
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Rose Dawn Bharath
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Pardeep Kumar
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
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Jacobs AH, Schelhaas S, Viel T, Waerzeggers Y, Winkeler A, Zinnhardt B, Gelovani J. Imaging of Gene and Cell-Based Therapies: Basis and Clinical Trials. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00060-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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22
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Ramadurgum P, Daniel S, Hulleman JD. Protocol for In Vivo Evaluation and Use of Destabilizing Domains in the Eye, Liver, and Beyond. STAR Protoc 2020; 1. [PMID: 32995756 PMCID: PMC7521670 DOI: 10.1016/j.xpro.2020.100094] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Destabilizing domains (DDs) have been used successfully to conditionally control the abundance of proteins of interest (POIs) in a small-molecule-dependent manner in mice, worms (Caenorhabditis elegans), and Drosophila. However, development of such systems must account for delivery of the DD-POIs to the target tissue, accessibility of the target tissue to the small molecule, and quantification of stabilization. Here, we describe the considerations and steps to take in order to effectively implement a DD-POI in mouse ocular and hepatic tissue. For complete details on the use and execution of this protocol, please refer to Datta et al. (2018), Ramadurgum and Hulleman (2020), and Ramadurgum et al. (2020).
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Affiliation(s)
- Prerana Ramadurgum
- Department of Ophthalmology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Steffi Daniel
- Department of Ophthalmology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - John D Hulleman
- Department of Ophthalmology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA.,Department of Pharmacology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA.,Technical Contact
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Ashmore-Harris C, Iafrate M, Saleem A, Fruhwirth GO. Non-invasive Reporter Gene Imaging of Cell Therapies, including T Cells and Stem Cells. Mol Ther 2020; 28:1392-1416. [PMID: 32243834 PMCID: PMC7264441 DOI: 10.1016/j.ymthe.2020.03.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/15/2020] [Accepted: 03/18/2020] [Indexed: 12/14/2022] Open
Abstract
Cell therapies represent a rapidly emerging class of new therapeutics. They are intended and developed for the treatment of some of the most prevalent human diseases, including cancer, diabetes, and for regenerative medicine. Currently, they are largely developed without precise assessment of their in vivo distribution, efficacy, or survival either clinically or preclinically. However, it would be highly beneficial for both preclinical cell therapy development and subsequent clinical use to assess these parameters in situ to enable enhancements in efficacy, applicability, and safety. Molecular imaging can be exploited to track cells non-invasively on the whole-body level and can enable monitoring for prolonged periods in a manner compatible with rapidly expanding cell types. In this review, we explain how in vivo imaging can aid the development and clinical translation of cell-based therapeutics. We describe the underlying principles governing non-invasive in vivo long-term cell tracking in the preclinical and clinical settings, including available imaging technologies, reporter genes, and imaging agents as well as pitfalls related to experimental design. Our emphasis is on adoptively transferred T cell and stem cell therapies.
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Affiliation(s)
- Candice Ashmore-Harris
- Imaging Therapy and Cancer Group, Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, UK; Centre for Stem Cells and Regenerative Medicine, School of Basic and Medical Biosciences, King's College London, London SE1 9RT, UK
| | - Madeleine Iafrate
- Imaging Therapy and Cancer Group, Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, UK
| | - Adeel Saleem
- Imaging Therapy and Cancer Group, Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, UK; Peter Gorer Department of Immunobiology, School of Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK; Department of Haematological Medicine, King's College Hospital, London SE5 9RS, UK
| | - Gilbert O Fruhwirth
- Imaging Therapy and Cancer Group, Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, UK.
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Iafrate M, Fruhwirth GO. How Non-invasive in vivo Cell Tracking Supports the Development and Translation of Cancer Immunotherapies. Front Physiol 2020; 11:154. [PMID: 32327996 PMCID: PMC7152671 DOI: 10.3389/fphys.2020.00154] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 02/12/2020] [Indexed: 12/26/2022] Open
Abstract
Immunotherapy is a relatively new treatment regimen for cancer, and it is based on the modulation of the immune system to battle cancer. Immunotherapies can be classified as either molecular or cell-based immunotherapies, and both types have demonstrated promising results in a growing number of cancers. Indeed, several immunotherapies representing both classes are already approved for clinical use in oncology. While spectacular treatment successes have been reported, particularly for so-called immune checkpoint inhibitors and certain cell-based immunotherapies, they have also been accompanied by a variety of severe, sometimes life-threatening side effects. Furthermore, not all patients respond to immunotherapy. Hence, there is the need for more research to render these promising therapeutics more efficacious, more widely applicable, and safer to use. Whole-body in vivo imaging technologies that can interrogate cancers and/or immunotherapies are highly beneficial tools for immunotherapy development and translation to the clinic. In this review, we explain how in vivo imaging can aid the development of molecular and cell-based anti-cancer immunotherapies. We describe the principles of imaging host T-cells and adoptively transferred therapeutic T-cells as well as the value of traceable cancer cell models in immunotherapy development. Our emphasis is on in vivo cell tracking methodology, including important aspects and caveats specific to immunotherapies. We discuss a variety of associated experimental design aspects including parameters such as cell type, observation times/intervals, and detection sensitivity. The focus is on non-invasive 3D cell tracking on the whole-body level including aspects relevant for both preclinical experimentation and clinical translatability of the underlying methodologies.
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Affiliation(s)
| | - Gilbert O. Fruhwirth
- Imaging Therapy and Cancer Group, Department of Imaging Chemistry and Biology, School of Biomedical Engineering & Imaging Sciences, King’s College London, London, United Kingdom
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Northrup JD, Mach RH, Sellmyer MA. Radiochemical Approaches to Imaging Bacterial Infections: Intracellular versus Extracellular Targets. Int J Mol Sci 2019; 20:E5808. [PMID: 31752318 PMCID: PMC6888724 DOI: 10.3390/ijms20225808] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 11/04/2019] [Accepted: 11/12/2019] [Indexed: 02/03/2023] Open
Abstract
The discovery of penicillin began the age of antibiotics, which was a turning point in human healthcare. However, to this day, microbial infections are still a concern throughout the world, and the rise of multidrug-resistant organisms is an increasing challenge. To combat this threat, diagnostic imaging tools could be used to verify the causative organism and curb inappropriate use of antimicrobial drugs. Nuclear imaging offers the sensitivity needed to detect small numbers of bacteria in situ. Among nuclear imaging tools, radiolabeled antibiotics traditionally have lacked the sensitivity or specificity necessary to diagnose bacterial infections accurately. One reason for the lack of success is that the antibiotics were often chelated to a radiometal. This was done without addressing the ramifications of how the radiolabeling would impact probe entry to the bacterial cell, or the mechanism of binding to an intracellular target. In this review, we approach bacterial infection imaging through the lens of bacterial specific molecular targets, their intracellular or extracellular location, and discuss radiochemistry strategies to guide future probe development.
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Affiliation(s)
- Justin D. Northrup
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA; (J.D.N.); (R.H.M.)
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert H. Mach
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA; (J.D.N.); (R.H.M.)
| | - Mark A. Sellmyer
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA; (J.D.N.); (R.H.M.)
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA
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Sellmyer MA, Richman SA, Lohith K, Hou C, Weng CC, Mach RH, O'Connor RS, Milone MC, Farwell MD. Imaging CAR T Cell Trafficking with eDHFR as a PET Reporter Gene. Mol Ther 2019; 28:42-51. [PMID: 31668558 DOI: 10.1016/j.ymthe.2019.10.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 10/07/2019] [Accepted: 10/09/2019] [Indexed: 01/11/2023] Open
Abstract
Cell-based therapeutics have considerable promise across diverse medical specialties; however, reliable human imaging of the distribution and trafficking of genetically engineered cells remains a challenge. We developed positron emission tomography (PET) probes based on the small-molecule antibiotic trimethoprim (TMP) that can be used to image the expression of the Escherichia coli dihydrofolate reductase enzyme (eDHFR) and tested the ability of [18F]-TMP, a fluorine-18 probe, to image primary human chimeric antigen receptor (CAR) T cells expressing the PET reporter gene eDHFR, yellow fluorescent protein (YFP), and Renilla luciferase (rLuc). Engineered T cells showed an approximately 50-fold increased bioluminescent imaging signal and 10-fold increased [18F]-TMP uptake compared to controls in vitro. eDHFR-expressing anti-GD2 CAR T cells were then injected into mice bearing control GD2- and GD2+ tumors. PET/computed tomography (CT) images acquired on days 7 and 13 demonstrated early residency of CAR T cells in the spleen followed by on-target redistribution to the GD2+ tumors. This was corroborated by autoradiography and anti-human CD8 immunohistochemistry. We found a high sensitivity of detection for identifying tumor-infiltrating CD8 CAR T cells, ∼11,000 cells per mm3. These data suggest that the [18F]-TMP/eDHFR PET pair offers important advantages that could better allow investigators to monitor immune cell trafficking to tumors in patients.
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Affiliation(s)
- Mark A Sellmyer
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Sarah A Richman
- Division of Oncology, Department of Pediatrics, Children's Hospital of Philadelphia and Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Katheryn Lohith
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Catherine Hou
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Chi-Chang Weng
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan 33302, Taiwan
| | - Robert H Mach
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Roddy S O'Connor
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael C Milone
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael D Farwell
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Sellmyer MA, Lee I, Hou C, Weng CC, Li S, Lieberman BP, Zeng C, Mankoff DA, Mach RH. Bacterial infection imaging with [ 18F]fluoropropyl-trimethoprim. Proc Natl Acad Sci U S A 2017; 114:8372-8377. [PMID: 28716936 PMCID: PMC5547613 DOI: 10.1073/pnas.1703109114] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
There is often overlap in the diagnostic features of common pathologic processes such as infection, sterile inflammation, and cancer both clinically and using conventional imaging techniques. Here, we report the development of a positron emission tomography probe for live bacterial infection based on the small-molecule antibiotic trimethoprim (TMP). [18F]fluoropropyl-trimethoprim, or [18F]FPTMP, shows a greater than 100-fold increased uptake in vitro in live bacteria (Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa) relative to controls. In a rodent myositis model, [18F]FPTMP identified live bacterial infection without demonstrating confounding increased signal in the same animal from other etiologies including chemical inflammation (turpentine) and cancer (breast carcinoma). Additionally, the biodistribution of [18F]FPTMP in a nonhuman primate shows low background in many important tissues that may be sites of infection such as the lungs and soft tissues. These results suggest that [18F]FPTMP could be a broadly useful agent for the sensitive and specific imaging of bacterial infection with strong translational potential.
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Affiliation(s)
- Mark A Sellmyer
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104
| | - Iljung Lee
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104
| | - Catherine Hou
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104
| | - Chi-Chang Weng
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104
| | - Shihong Li
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104
| | - Brian P Lieberman
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104
| | - Chenbo Zeng
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104
| | - David A Mankoff
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104
| | - Robert H Mach
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104
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