1
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Akter A, Firth G, Darwesh AMF, Cooper MS, Chuljerm H, Cilibrizzi A, Blower PJ, Hider RC, Lyons O, Schelenz S, Mehra V, Abbate V. [ 68Ga]Ga-Schizokinen, a Potential Radiotracer for Selective Bacterial Infection Imaging. ACS Infect Dis 2024; 10:2615-2622. [PMID: 39012184 PMCID: PMC11320569 DOI: 10.1021/acsinfecdis.4c00067] [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: 01/22/2024] [Revised: 07/02/2024] [Accepted: 07/03/2024] [Indexed: 07/17/2024]
Abstract
Gallium-68-labeled siderophores as radiotracers have gained interest for the development of in situ infection-specific imaging diagnostics. Here, we report radiolabeling, in vitro screening, and in vivo pharmacokinetics (PK) of gallium-68-labeled schizokinen ([68Ga]Ga-SKN) as a new potential radiotracer for imaging bacterial infections. We radiolabeled SKN with ≥95% radiochemical purity. Our in vitro studies demonstrated its hydrophilic characteristics, neutral pH stability, and short-term stability in human serum and toward transchelation. In vitro uptake of [68Ga]Ga-SKN by Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and S. epidermidis, but no uptake by Candida glabrata, C. albicans, or Aspergillus fumigatus, demonstrated its specificity to bacterial species. Whole-body [68Ga]Ga-SKN positron emission tomography (PET) combined with computerized tomography (CT) in healthy mice showed rapid renal excretion with no or minimal organ uptake. The subsequent ex vivo biodistribution resembled this fast PK with rapid renal excretion with minimal blood retention and no major organ uptake and showed some dissociation of the tracer in the urine after 60 min postinjection. These findings warrant further evaluation of [68Ga]Ga-SKN as a bacteria-specific radiotracer for infection imaging.
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Affiliation(s)
- Asma Akter
- Institute
of Pharmaceutical Science, Faculty of Life Science and Medicine, King’s College London, London SE1 9NH, United Kingdom
| | - George Firth
- School
of Biomedical Engineering and Imaging Sciences, Faculty of Life Science
and Medicine, King’s College London, London SE1 7EH, United Kingdom
| | - Afnan M. F. Darwesh
- School
of Biomedical Engineering and Imaging Sciences, Faculty of Life Science
and Medicine, King’s College London, London SE1 7EH, United Kingdom
- Department
of Radiologic Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Margaret S. Cooper
- School
of Biomedical Engineering and Imaging Sciences, Faculty of Life Science
and Medicine, King’s College London, London SE1 7EH, United Kingdom
| | - Hataichanok Chuljerm
- Institute
of Pharmaceutical Science, Faculty of Life Science and Medicine, King’s College London, London SE1 9NH, United Kingdom
- School
of Health Sciences Research, Research Institute for Health Sciences, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Agostino Cilibrizzi
- Institute
of Pharmaceutical Science, Faculty of Life Science and Medicine, King’s College London, London SE1 9NH, United Kingdom
| | - Philip J. Blower
- School
of Biomedical Engineering and Imaging Sciences, Faculty of Life Science
and Medicine, King’s College London, London SE1 7EH, United Kingdom
| | - Robert C. Hider
- Institute
of Pharmaceutical Science, Faculty of Life Science and Medicine, King’s College London, London SE1 9NH, United Kingdom
| | - Oliver Lyons
- Department
of Surgery, University of Otago, Christchurch 8013, New Zealand
| | - Silke Schelenz
- Department
of Microbiology, Kings College Hospital
NHS Foundation Trust, London SE5 9RS, United
Kingdom
| | - Varun Mehra
- Department
of Hematology, King’s College Hospital
NHS Foundation Trust, London SE5 9RS, United
Kingdom
| | - Vincenzo Abbate
- Institute
of Pharmaceutical Science, Faculty of Life Science and Medicine, King’s College London, London SE1 9NH, United Kingdom
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2
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Betts HM, Luckett JC, Hill PJ. Pilot Evaluation of S-(3-[ 18F]Fluoropropyl)-D-Homocysteine and O-(2-[ 18F]Fluoroethyl)-D-Tyrosine as Bacteria-Specific Radiotracers for PET Imaging of Infection. Mol Imaging Biol 2024; 26:704-713. [PMID: 38942967 PMCID: PMC11282134 DOI: 10.1007/s11307-024-01929-7] [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: 02/05/2024] [Revised: 06/12/2024] [Accepted: 06/14/2024] [Indexed: 06/30/2024]
Abstract
PURPOSE There is currently no ideal radiotracer for imaging bacterial infections. Radiolabelled D-amino acids are promising candidates because they are actively incorporated into the peptidoglycan of the bacterial cell wall, a structural feature which is absent in human cells. This work describes fluorine-18 labelled analogues of D-tyrosine and D-methionine, O-(2-[18F]fluoroethyl)-D-tyrosine (D-[18F]FET) and S-(3-[18F]fluoropropyl)-D-homocysteine (D-[18F]FPHCys), and their pilot evaluation studies as potential radiotracers for imaging bacterial infection. PROCEDURES D-[18F]FET and D-[18F]FPHCys were prepared in classical fluorination-deprotection reactions, and their uptake in Staphylococcus aureus and Pseudomonas aeruginosa was evaluated over 2 h. Heat killed bacteria were used as controls. A clinically-relevant foreign body model of S. aureus infection was established in Balb/c mice, as well as a sterile foreign body to mimic inflammation. The ex vivo biodistribution of D-[18F]FPHCys in the infected and inflamed mice was evaluated after 1 h, by dissection and gamma counting. The uptake was compared to that of [18F]FDG. RESULTS In vitro uptake of both D-[18F]FET and D-[18F]FPHCys was specific to live bacteria. Uptake was higher in S. aureus than in P. aeruginosa for both radiotracers, and of the two, higher for D-[18F]FPHCys than D-[18F]FET. Blocking experiments with non-radioactive D-[19F]FPHCys confirmed specificity of uptake. In vivo, D-[18F]FPHCys had greater accumulation in S. aureus infection compared with sterile inflammation, which was statistically significant. As anticipated, [18F]FDG showed no significant difference in uptake between infection and inflammation. CONCLUSIONS D-[18F]FPHCys uptake was higher in infected tissues than inflammation, and represents a fluorine-18 labelled D-AA with potential to detect a S. aureus reference strain (Xen29) in vivo. Additional studies are needed to evaluate uptake of this radiotracer in clinical isolates.
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Affiliation(s)
- Helen M Betts
- Department of Nuclear Medicine, Nottingham University Hospitals NHS Trust, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
- School of Medicine, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
| | - Jeni C Luckett
- School of Life Sciences, University of Nottingham, Biodiscovery Institute, University Park, Nottingham, NG7 2RD, UK
| | - Philip J Hill
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Sutton Bonington, LE17 5RD, UK
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3
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Li K, Tolentino Collado J, Marden JA, Pollard AC, Guo S, Tonge PJ, Qu W. Biological Evaluation of d-[ 18F]Fluoroalanine and d-[ 18F]Fluoroalanine- d3 as Positron Emission Tomography Imaging Tracers for Bacterial Infection. J Med Chem 2024. [PMID: 39082959 DOI: 10.1021/acs.jmedchem.4c00783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
d-Amino acids such as d-alanine are substrates for bacterial peptidoglycan biosynthesis and are selectively taken up by bacteria and not mammalian cells. Consequently, d-amino acid metabolism is an attractive target for antibiotic discovery and the development of bacteria-specific imaging agents. d-Fluoroalanine and the deuterium-labeled analogue fludalanine (MK641) were originally explored as antibiotics by Merck but failed in clinical trials due to unaccepted toxicity. Herein, we synthesized a fluorine-18 labeled d-fluoroalanine, d-3-[18F]fluoroalanine (d-[18F]FAla), and its deuterated analogue, d-3-[18F]fluoroalanine-d3 (d-[18F]FAla-d3), and evaluated their capability to image bacterial infection. Both d-[18F]FAla and d-[18F]FAla-d3 can accumulate up to 0.64-0.78% ID/cc in the infectious area at 15 min postinjection. Despite the reduction of in vivo defluorination not being observed for deuterated 18F-labeled d-fluoroalanine, these radiolabeled d-alanine analogues were able to differentiate bacterial infection from sterile inflammation in a soft-tissue model of S. aureus infection.
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Affiliation(s)
- Kaixuan Li
- Center for Advanced Study of Drug Action, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
- Department of Chemistry, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
| | - Jinnette Tolentino Collado
- Center for Advanced Study of Drug Action, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
- Department of Chemistry, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
| | - Jocelyn A Marden
- Department of Psychiatry and Behavioral Health, Stony Brook Renaissance School of Medicine, Stony Brook University, Stony Brook, New York 11794, United States
| | - Alyssa C Pollard
- Center for Advanced Study of Drug Action, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
- Department of Chemistry, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
| | - Shuwen Guo
- Center for Advanced Study of Drug Action, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
- Department of Chemistry, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
| | - Peter J Tonge
- Center for Advanced Study of Drug Action, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
- Department of Chemistry, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
- Department of Radiology, Stony Brook Renaissance School of Medicine, Stony Brook University, Stony Brook, New York 11794, United States
- Stony Brook Cancer Center, Stony Brook Renaissance School of Medicine, Stony Brook University, Stony Brook, New York 11794, United States
| | - Wenchao Qu
- Department of Chemistry, Stony Brook University, John S. Toll Drive, Stony Brook, New York 11794-3400, United States
- Department of Psychiatry and Behavioral Health, Stony Brook Renaissance School of Medicine, Stony Brook University, Stony Brook, New York 11794, United States
- PET Research Core, Stony Brook Renaissance School of Medicine, Stony Brook University, Stony Brook, New York 11794, United States
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4
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Kahts M, Summers B, Gutta A, Pilloy W, Ebenhan T. Recently developed radiopharmaceuticals for bacterial infection imaging. EJNMMI Radiopharm Chem 2024; 9:49. [PMID: 38896373 PMCID: PMC11187059 DOI: 10.1186/s41181-024-00279-7] [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: 04/18/2024] [Accepted: 06/10/2024] [Indexed: 06/21/2024] Open
Abstract
BACKGROUND Infection remains a major cause of morbidity and mortality, regardless of advances in antimicrobial therapy and improved knowledge of microorganisms. With the major global threat posed by antimicrobial resistance, fast and accurate diagnosis of infections, and the reliable identification of intractable infection, are becoming more crucial for effective treatment and the application of antibiotic stewardship. Molecular imaging with the use of nuclear medicine allows early detection and localisation of infection and inflammatory processes, as well as accurate monitoring of treatment response. There has been a continuous search for more specific radiopharmaceuticals to be utilised for infection imaging. This review summarises the most prominent discoveries in specifically bacterial infection imaging agents over the last five years, since 2019. MAIN BODY Some promising new radiopharmaceuticals evaluated in patient studies are reported here, including radiolabelled bacterial siderophores like [68Ga]Ga-DFO-B, radiolabelled antimicrobial peptide/peptide fragments like [68Ga]Ga-NOTA-UBI29-41, and agents that target bacterial synthesis pathways (folic acid and peptidoglycan) like [11C]para-aminobenzoic acid and D-methyl-[11C]-methionine, with clinical trials underway for [18F]fluorodeoxy-sorbitol, as well as for 11C- and 18F-labelled trimethoprim. CONCLUSION It is evident that a great deal of effort has gone into the development of new radiopharmaceuticals for infection imaging over the last few years, with remarkable progress in preclinical investigations. However, translation to clinical trials, and eventually clinical Nuclear Medicine practice, is apparently slow. It is the authors' opinion that a more structured and harmonised preclinical setting and well-designed clinical investigations are the key to reliably evaluate the true potential of the newly proposed infection imaging agents.
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Affiliation(s)
- Maryke Kahts
- Pharmaceutical Sciences Department, School of Pharmacy, Sefako Makgatho Health Sciences University, Ga-Rankuwa, 0208, South Africa.
| | - Beverley Summers
- Pharmaceutical Sciences Department, School of Pharmacy, Sefako Makgatho Health Sciences University, Ga-Rankuwa, 0208, South Africa
| | - Aadil Gutta
- Nuclear Medicine Department, Dr George Mukhari Academic Hospital, Ga-Rankuwa, 0208, South Africa
- School of Medicine, Sefako Makgatho Health Sciences University, Ga-Rankuwa, 0208, South Africa
| | - Wilfrid Pilloy
- Nuclear Medicine Department, Dr George Mukhari Academic Hospital, Ga-Rankuwa, 0208, South Africa
| | - Thomas Ebenhan
- Nuclear Medicine Department and Nuclear Medicine Research Infrastructure, University of Pretoria, Pretoria, 0001, South Africa
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5
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Zheng Y, Zhu X, Jiang M, Cao F, You Q, Chen X. Development and Applications of D-Amino Acid Derivatives-based Metabolic Labeling of Bacterial Peptidoglycan. Angew Chem Int Ed Engl 2024; 63:e202319400. [PMID: 38284300 DOI: 10.1002/anie.202319400] [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: 12/18/2023] [Revised: 01/28/2024] [Accepted: 01/29/2024] [Indexed: 01/30/2024]
Abstract
Peptidoglycan, an essential component within the cell walls of virtually all bacteria, is composed of glycan strands linked by stem peptides that contain D-amino acids. The peptidoglycan biosynthesis machinery exhibits high tolerance to various D-amino acid derivatives. D-amino acid derivatives with different functionalities can thus be specifically incorporated into and label the peptidoglycan of bacteria, but not the host mammalian cells. This metabolic labeling strategy is highly selective, highly biocompatible, and broadly applicable, which has been utilized in various fields. This review introduces the metabolic labeling strategies of peptidoglycan by using D-amino acid derivatives, including one-step and two-step strategies. In addition, we emphasize the various applications of D-amino acid derivative-based metabolic labeling, including bacterial peptidoglycan visualization (existence, biosynthesis, and dynamics, etc.), bacterial visualization (including bacterial imaging and visualization of growth and division, metabolic activity, antibiotic susceptibility, etc.), pathogenic bacteria-targeted diagnostics and treatment (positron emission tomography (PET) imaging, photodynamic therapy, photothermal therapy, gas therapy, immunotherapy, etc.), and live bacteria-based therapy. Finally, a summary of this metabolic labeling and an outlook is provided.
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Affiliation(s)
- Yongfang Zheng
- Fujian-Taiwan Science and Technology Cooperation Base of Biomedical Materials and Tissue Engineering, Engineering Research Center of Industrial Biocatalysis, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, 32 Shangsan Road, Fuzhou, 350007, P.R. China
| | - Xinyu Zhu
- Fujian-Taiwan Science and Technology Cooperation Base of Biomedical Materials and Tissue Engineering, Engineering Research Center of Industrial Biocatalysis, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, 32 Shangsan Road, Fuzhou, 350007, P.R. China
| | - Mingyi Jiang
- Fujian-Taiwan Science and Technology Cooperation Base of Biomedical Materials and Tissue Engineering, Engineering Research Center of Industrial Biocatalysis, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, 32 Shangsan Road, Fuzhou, 350007, P.R. China
| | - Fangfang Cao
- Departments of Diagnostic Radiology, Surgery, Chemical and Biomolecular Engineering, and Biomedical Engineering, Yong Loo Lin School of Medicine and Faculty of Engineering, National University of Singapore, Singapore, 119074, Singapore
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117599, Singapore
| | - Qing You
- Departments of Diagnostic Radiology, Surgery, Chemical and Biomolecular Engineering, and Biomedical Engineering, Yong Loo Lin School of Medicine and Faculty of Engineering, National University of Singapore, Singapore, 119074, Singapore
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117599, Singapore
| | - Xiaoyuan Chen
- Departments of Diagnostic Radiology, Surgery, Chemical and Biomolecular Engineering, and Biomedical Engineering, Yong Loo Lin School of Medicine and Faculty of Engineering, National University of Singapore, Singapore, 119074, Singapore
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117599, Singapore
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6
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Alanizi AA, Sorlin AM, Parker MFL, López-Álvarez M, Qin H, Lee SH, Blecha J, Rosenberg OS, Engel J, Ohliger MA, Flavell RR, Wilson DM. Bioorthogonal Radiolabeling of Azide-Modified Bacteria Using [ 18F]FB-sulfo-DBCO. Bioconjug Chem 2024; 35:517-527. [PMID: 38482815 PMCID: PMC11036355 DOI: 10.1021/acs.bioconjchem.4c00024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 02/27/2024] [Accepted: 02/27/2024] [Indexed: 04/18/2024]
Abstract
Purpose: This study was motivated by the need for better positron emission tomography (PET)-compatible tools to image bacterial infection. Our previous efforts have targeted bacteria-specific metabolism via assimilation of carbon-11 labeled d-amino acids into the bacterial cell wall. Since the chemical determinants of this incorporation are not fully understood, we sought a high-throughput method to label d-amino acid derived structures with fluorine-18. Our strategy employed a chemical biology approach, whereby an azide (-N3) bearing d-amino acid is incorporated into peptidoglycan muropeptides, with subsequent "click" cycloaddition with an 18F-labeled strained cyclooctyne partner. Procedures: A water-soluble, 18F-labeled and dibenzocyclooctyne (DBCO)-derived radiotracer ([18F]FB-sulfo-DBCO) was synthesized. This tracer was incubated with pathogenic bacteria treated with azide-bearing d-amino acids, and incorporated 18F was determined via gamma counting. In vitro uptake in bacteria previously treated with azide-modified d-amino acids was compared to that in cultures treated with amino acid controls. The biodistribution of [18F]FB-sulfo-DBCO was studied in a cohort of healthy mice with implications for future in vivo imaging. Results: The new strain-promoted azide-alkyne cycloaddition (SPAAC) radiotracer [18F]FB-sulfo-DBCO was synthesized with high radiochemical yield and purity via N-succinimidyl 4-[18F]fluorobenzoate ([18F]SFB). Accumulation of [18F]FB-sulfo-DBCO was significantly higher in several bacteria treated with azide-modified d-amino acids than in controls; for example, we observed 7 times greater [18F]FB-sulfo-DBCO ligation in Staphylococcus aureus cultures incubated with 3-azido-d-alanine versus those incubated with d-alanine. Conclusions: The SPAAC radiotracer [18F]FB-sulfo-DBCO was validated in vitro via metabolic labeling of azide-bearing peptidoglycan muropeptides. d-Amino acid-derived PET radiotracers may be more efficiently screened via [18F]FB-sulfo-DBCO modification.
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Affiliation(s)
- Aryn A. Alanizi
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Alexandre M. Sorlin
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Matthew F. L. Parker
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
- Department
of Psychiatry, Renaissance School of Medicine
at Stony Brook University, Stony
Brook, New York 11794, United States
| | - Marina López-Álvarez
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Hecong Qin
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Sang Hee Lee
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Joseph Blecha
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Oren S. Rosenberg
- Department
of Medicine, University of California, San
Francisco, San Francisco, California 94158, United States
| | - Joanne Engel
- Department
of Medicine, University of California, San
Francisco, San Francisco, California 94158, United States
| | - Michael A. Ohliger
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
- Department
of Radiology, Zuckerberg San Francisco General
Hospital, San Francisco, California 94110, United States
| | - Robert R. Flavell
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - David M. Wilson
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
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7
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Sorlin A, López-Álvarez M, Biboy J, Gray J, Rabbitt SJ, Rahim JU, Lee SH, Bobba KN, Blecha J, Parker MF, Flavell RR, Engel J, Ohliger M, Vollmer W, Wilson DM. Peptidoglycan-Targeted [ 18F]3,3,3-Trifluoro-d-alanine Tracer for Imaging Bacterial Infection. JACS AU 2024; 4:1039-1047. [PMID: 38559735 PMCID: PMC10976610 DOI: 10.1021/jacsau.3c00776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/19/2024] [Accepted: 02/06/2024] [Indexed: 04/04/2024]
Abstract
Imaging is increasingly used to detect and monitor bacterial infection. Both anatomic (X-rays, computed tomography, ultrasound, and MRI) and nuclear medicine ([111In]-WBC SPECT, [18F]FDG PET) techniques are used in clinical practice but lack specificity for the causative microorganisms themselves. To meet this challenge, many groups have developed imaging methods that target pathogen-specific metabolism, including PET tracers integrated into the bacterial cell wall. We have previously reported the d-amino acid derived PET radiotracers d-methyl-[11C]-methionine, d-[3-11C]-alanine, and d-[3-11C]-alanine-d-alanine, which showed robust bacterial accumulation in vitro and in vivo. Given the clinical importance of radionuclide half-life, in the current study, we developed [18F]3,3,3-trifluoro-d-alanine (d-[18F]-CF3-ala), a fluorine-18 labeled tracer. We tested the hypothesis that d-[18F]-CF3-ala would be incorporated into bacterial peptidoglycan given its structural similarity to d-alanine itself. NMR analysis showed that the fluorine-19 parent amino acid d-[19F]-CF3-ala was stable in human and mouse serum. d-[19F]-CF3-ala was also a poor substrate for d-amino acid oxidase, the enzyme largely responsible for mammalian d-amino acid metabolism and a likely contributor to background signals using d-amino acid derived PET tracers. In addition, d-[19F]-CF3-ala showed robust incorporation into Escherichia coli peptidoglycan, as detected by HPLC/mass spectrometry. Based on these promising results, we developed a radiosynthesis of d-[18F]-CF3-ala via displacement of a bromo-precursor with [18F]fluoride followed by chiral stationary phase HPLC. Unexpectedly, the accumulation of d-[18F]-CF3-ala by bacteria in vitro was highest for Gram-negative pathogens in particular E. coli. In a murine model of acute bacterial infection, d-[18F]-CF3-ala could distinguish live from heat-killed E. coli, with low background signals. These results indicate the viability of [18F]-modified d-amino acids for infection imaging and indicate that improved specificity for bacterial metabolism can improve tracer performance.
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Affiliation(s)
- Alexandre
M. Sorlin
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
| | - Marina López-Álvarez
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
| | - Jacob Biboy
- The
Centre for Bacterial Cell Biology, Newcastle
University Newcastle, Newcastle
upon Tyne NE2 4AX, United Kingdom
| | - Joe Gray
- The
Centre for Bacterial Cell Biology, Newcastle
University Newcastle, Newcastle
upon Tyne NE2 4AX, United Kingdom
| | - Sarah J. Rabbitt
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
| | - Junaid Ur Rahim
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
| | - Sang Hee Lee
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
| | - Kondapa Naidu Bobba
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
| | - Joseph Blecha
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
| | - Mathew F.L. Parker
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
- Department
of Psychiatry, Renaissance School of Medicine
at Stony Brook University, Stony Brook, New York 11794, United States
| | - Robert R. Flavell
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
- UCSF
Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, California 94158, United States
- Department
of Pharmaceutical Chemistry, University
of California, San Francisco, San
Francisco, California 94158, United States
| | - Joanne Engel
- Department
of Medicine, University of California, San
Francisco, San Francisco, California 94158, United States
- Department
of Microbiology and Immunology, University
of California, San Francisco, San
Francisco, California 94158, United States
| | - Michael Ohliger
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
- Department
of Radiology, Zuckerberg San Francisco General
Hospital, San Francisco, California 94110, United States
| | - Waldemar Vollmer
- The
Centre for Bacterial Cell Biology, Newcastle
University Newcastle, Newcastle
upon Tyne NE2 4AX, United Kingdom
- Institute
for Molecular Bioscience, The University
of Queensland, Brisbane 4072, Australia
| | - David M. Wilson
- Department
of Radiology, Biomedical Imaging University
of California, San Francisco, San Francisco, California 94158, United States
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8
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Koatale P, Welling MM, Ndlovu H, Kgatle M, Mdanda S, Mdlophane A, Okem A, Takyi-Williams J, Sathekge MM, Ebenhan T. Insights into Peptidoglycan-Targeting Radiotracers for Imaging Bacterial Infections: Updates, Challenges, and Future Perspectives. ACS Infect Dis 2024; 10:270-286. [PMID: 38290525 PMCID: PMC10862554 DOI: 10.1021/acsinfecdis.3c00443] [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: 08/28/2023] [Revised: 12/16/2023] [Accepted: 12/18/2023] [Indexed: 02/01/2024]
Abstract
The unique structural architecture of the peptidoglycan allows for the stratification of bacteria as either Gram-negative or Gram-positive, which makes bacterial cells distinguishable from mammalian cells. This classification has received attention as a potential target for diagnostic and therapeutic purposes. Bacteria's ability to metabolically integrate peptidoglycan precursors during cell wall biosynthesis and recycling offers an opportunity to target and image pathogens in their biological state. This Review explores the peptidoglycan biosynthesis for bacteria-specific targeting for infection imaging. Current and potential radiolabeled peptidoglycan precursors for bacterial infection imaging, their development status, and their performance in vitro and/or in vivo are highlighted. We conclude by providing our thoughts on how to shape this area of research for future clinical translation.
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Affiliation(s)
- Palesa
C. Koatale
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Mick M. Welling
- Interventional
Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Honest Ndlovu
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Mankgopo Kgatle
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Sipho Mdanda
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Amanda Mdlophane
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Ambrose Okem
- Department
of Anaesthesia, School of Clinical Medicine, University of Witwatersrand, 2050 Johannesburg, South Africa
| | - John Takyi-Williams
- Pharmacokinetic
and Mass Spectrometry Core, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Mike M. Sathekge
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Thomas Ebenhan
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
- DSI/NWU Pre-clinical
Drug Development Platform, North West University, 2520 Potchefstroom, South Africa
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9
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Roll W, Faust A, Hermann S, Schäfers M. Infection Imaging: Focus on New Tracers? J Nucl Med 2023; 64:59S-67S. [PMID: 37918846 DOI: 10.2967/jnumed.122.264869] [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: 02/16/2023] [Revised: 05/31/2023] [Indexed: 11/04/2023] Open
Abstract
Infections account for relevant morbidity and mortality, especially if the cardiovascular system is affected. Clinical manifestations are often unspecific, resulting in a challenging diagnostic work-up. The use of molecular imaging methods, namely [18F]FDG PET and leukocyte scintigraphy, is increasingly recognized in recently published international guidelines. However, these 2 established methods focus on the host's immune response to the pathogen and are therefore virtually unable to differentiate infection from inflammation. Targeting the microorganism responsible for the infection directly with novel imaging agents is a promising strategy to overcome these limitations. In this review, we discuss clinically approved [18F]FDG PET with its advantages and limitations in cardiovascular infections, followed by new PET-based approaches for the detection of cardiovascular infections by bacteria-specific molecular imaging methods. A multitude of different targeting options has already been preclinically evaluated, but most still lack clinical translation. We give an overview not only on promising tracer candidates for noninvasive molecular imaging of infections but also on issues hampering clinical translation.
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Affiliation(s)
- Wolfgang Roll
- Department of Nuclear Medicine, University Hospital Münster, Münster, Germany; and
| | - Andreas Faust
- Department of Nuclear Medicine, University Hospital Münster, Münster, Germany; and
- European Institute for Molecular Imaging, University of Münster, Münster, Germany
| | - Sven Hermann
- European Institute for Molecular Imaging, University of Münster, Münster, Germany
| | - Michael Schäfers
- Department of Nuclear Medicine, University Hospital Münster, Münster, Germany; and
- European Institute for Molecular Imaging, University of Münster, Münster, Germany
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10
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Blach A, Kwiecinski J. The Role of Positron Emission Tomography in Advancing the Understanding of the Pathogenesis of Heart and Vascular Diseases. Diagnostics (Basel) 2023; 13:1791. [PMID: 37238275 PMCID: PMC10217133 DOI: 10.3390/diagnostics13101791] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/14/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
Cardiovascular disease remains the leading cause of morbidity and mortality worldwide. For developing new therapies, a better understanding of the underlying pathology is required. Historically, such insights have been primarily derived from pathological studies. In the 21st century, thanks to the advent of cardiovascular positron emission tomography (PET), which depicts the presence and activity of pathophysiological processes, it is now feasible to assess disease activity in vivo. By targeting distinct biological pathways, PET elucidates the activity of the processes which drive disease progression, adverse outcomes or, on the contrary, those that can be considered as a healing response. Given the insights provided by PET, this non-invasive imaging technology lends itself to the development of new therapies, providing a hope for the emergence of strategies that could have a profound impact on patient outcomes. In this narrative review, we discuss recent advances in cardiovascular PET imaging which have greatly advanced our understanding of atherosclerosis, ischemia, infection, adverse myocardial remodeling and degenerative valvular heart disease.
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Affiliation(s)
- Anna Blach
- Department of Cardiology and Structural Heart Diseases, Medical University of Silesia, 40-055 Katowice, Poland
- Nuclear Medicine Department, Voxel Diagnostic Center, 40-514 Katowice, Poland
| | - Jacek Kwiecinski
- Department of Interventional Cardiology and Angiology, Institute of Cardiology, 04-628 Warsaw, Poland
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11
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Jiang Y, Fang S, Feng J, Ruan Q, Zhang J. Synthesis and Bioevaluation of Novel Technetium-99m-Labeled Complexes with Norfloxacin HYNIC Derivatives for Bacterial Infection Imaging. Mol Pharm 2023; 20:630-640. [PMID: 36398935 DOI: 10.1021/acs.molpharmaceut.2c00830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To seek a novel 99mTc-labeled quinolone derivative for bacterial infection SPECT imaging that aims to lower nontarget organ uptake, a novel norfloxacin 6-hydrazinoicotinamide (HYNIC) derivative (HYNICNF) was designed and synthesized. It was radiolabeled with different coligands, such as tricine, trisodium triphenylphosphine-3,3',3″-trisulfonate (TPPTS), sodium triphenylphosphine-3-monosulfonate (TPPMS), and ethylenediamine-N,N'-diacetic acid (EDDA), to obtain three 99mTc-labeled norfloxacin HYNIC complexes, namely, [99mTc]Tc-tricine-TPPTS-HYNICNF, [99mTc]Tc-tricine-TPPMS-HYNICNF, and [99mTc]Tc-EDDA-HYNICNF. These complexes were purified (RCP > 95%) and evaluated in vitro and in vivo for targeting bacteria. All three complexes are hydrophilic, maintain good stability, and specifically bind Staphylococcus aureus in vitro. The biodistribution in mice with bacterial infection demonstrated that [99mTc]Tc-EDDA-HYNICNF showed a higher abscess uptake and lower nontarget organ uptake and was able to distinguish bacterial infection and sterile inflammation. Single photon emission computed tomography (SPECT) image study in bacterial infection mice showed there was a visible accumulation in the infection site, suggesting that [99mTc]Tc-EDDA-HYNICNF is a potential radiotracer for bacterial infection imaging.
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Affiliation(s)
- Yuhao Jiang
- Key Laboratory of Radiopharmaceuticals of Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Radiopharmaceuticals (National Medical Product Administration), College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Si'an Fang
- Key Laboratory of Radiopharmaceuticals of Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Radiopharmaceuticals (National Medical Product Administration), College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Junhong Feng
- Key Laboratory of Radiopharmaceuticals of Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Radiopharmaceuticals (National Medical Product Administration), College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Qing Ruan
- Key Laboratory of Radiopharmaceuticals of Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Radiopharmaceuticals (National Medical Product Administration), College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Junbo Zhang
- Key Laboratory of Radiopharmaceuticals of Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Radiopharmaceuticals (National Medical Product Administration), College of Chemistry, Beijing Normal University, Beijing 100875, China
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12
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Huang H, Ali A, Liu Y, Xie H, Ullah S, Roy S, Song Z, Guo B, Xu J. Advances in image-guided drug delivery for antibacterial therapy. Adv Drug Deliv Rev 2023; 192:114634. [PMID: 36503884 DOI: 10.1016/j.addr.2022.114634] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/20/2022] [Accepted: 11/22/2022] [Indexed: 11/29/2022]
Abstract
The emergence of antibiotic-resistant bacterial strains is seriously endangering the global healthcare system. There is an urgent need for combining imaging with therapies to realize the real-time monitoring of pathological condition and treatment progress. It also provides guidance on exploring new medicines and enhance treatment strategies to overcome the antibiotic resistance of existing conventional antibiotics. In this review, we provide a thorough overview of the most advanced image-guided approaches for bacterial diagnosis (e.g., computed tomography imaging, magnetic resonance imaging, photoacoustic imaging, ultrasound imaging, fluorescence imaging, positron emission tomography, single photon emission computed tomography imaging, and multiple imaging), and therapies (e.g., photothermal therapy, photodynamic therapy, chemodynamic therapy, sonodynamic therapy, immunotherapy, and multiple therapies). This review focuses on how to design and fabricate photo-responsive materials for improved image-guided bacterial theranostics applications. We present a potential application of different image-guided modalities for both bacterial diagnosis and therapies with representative examples. Finally, we highlighted the current challenges and future perspectives image-guided approaches for future clinical translation of nano-theranostics in bacterial infections therapies. We envision that this review will provide for future development in image-guided systems for bacterial theranostics applications.
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Affiliation(s)
- Haiyan Huang
- Institute of Low-Dimensional Materials Genome Initiative, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China; School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology, Harbin Institute of Technology, Shenzhen 518055, China
| | - Arbab Ali
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nano Safety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
| | - Yi Liu
- State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Hui Xie
- Institute of Low-Dimensional Materials Genome Initiative, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China; Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China
| | - Sana Ullah
- Department of Biotechnology, Quaid-i-Azam University, Islamabad 45320, Pakistan; Natural and Medical Sciences Research Center, University of Nizwa, P.O. Box: 33, PC: 616, Oman
| | - Shubham Roy
- School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology, Harbin Institute of Technology, Shenzhen 518055, China
| | - Zhiyong Song
- State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, China.
| | - Bing Guo
- School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology, Harbin Institute of Technology, Shenzhen 518055, China.
| | - Jian Xu
- Institute of Low-Dimensional Materials Genome Initiative, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China.
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13
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Zhang Y, Hao M, Li L, Luo Q, Deng S, Yang Y, Liu Y, Fang W, Song E. Research progress of contrast agents for bacterial infection imaging in vivo. Trends Analyt Chem 2023. [DOI: 10.1016/j.trac.2023.116916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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14
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Shegani A, Kealey S, Luzi F, Basagni F, Machado JDM, Ekici SD, Ferocino A, Gee AD, Bongarzone S. Radiosynthesis, Preclinical, and Clinical Positron Emission Tomography Studies of Carbon-11 Labeled Endogenous and Natural Exogenous Compounds. Chem Rev 2022; 123:105-229. [PMID: 36399832 PMCID: PMC9837829 DOI: 10.1021/acs.chemrev.2c00398] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The presence of positron emission tomography (PET) centers at most major hospitals worldwide, along with the improvement of PET scanner sensitivity and the introduction of total body PET systems, has increased the interest in the PET tracer development using the short-lived radionuclides carbon-11. In the last few decades, methodological improvements and fully automated modules have allowed the development of carbon-11 tracers for clinical use. Radiolabeling natural compounds with carbon-11 by substituting one of the backbone carbons with the radionuclide has provided important information on the biochemistry of the authentic compounds and increased the understanding of their in vivo behavior in healthy and diseased states. The number of endogenous and natural compounds essential for human life is staggering, ranging from simple alcohols to vitamins and peptides. This review collates all the carbon-11 radiolabeled endogenous and natural exogenous compounds synthesised to date, including essential information on their radiochemistry methodologies and preclinical and clinical studies in healthy subjects.
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Affiliation(s)
- Antonio Shegani
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Steven Kealey
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Federico Luzi
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Filippo Basagni
- Department
of Pharmacy and Biotechnology, Alma Mater
Studiorum−University of Bologna, via Belmeloro 6, 40126 Bologna, Italy
| | - Joana do Mar Machado
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Sevban Doğan Ekici
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom
| | - Alessandra Ferocino
- Institute
of Organic Synthesis and Photoreactivity, Italian National Research Council, via Piero Gobetti 101, 40129 Bologna, Italy
| | - Antony D. Gee
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom,A.G.: email,
| | - Salvatore Bongarzone
- School
of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, United Kingdom,S.B.:
email,
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15
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Yue T, Tan H, Shi Y, Xu M, Luo S, Weng J, Xu S. Serum Metabolomic Profiling in Aging Mice Using Liquid Chromatography-Mass Spectrometry. Biomolecules 2022; 12:1594. [PMID: 36358944 PMCID: PMC9687663 DOI: 10.3390/biom12111594] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/20/2022] [Accepted: 10/27/2022] [Indexed: 07/30/2023] Open
Abstract
BACKGROUND The process of aging and metabolism are intricately linked, thus rendering the identification of reliable biomarkers related to metabolism crucial for delaying the aging process. However, research of reliable markers that reflect aging profiles based on machine learning is scarce. METHODS Serum samples were obtained from aged mice (18-month-old) and young mice (3-month-old). LC-MS was used to perform a comprehensive analysis of the serum metabolome and machine learning was used to screen potential aging-related biomarkers. RESULTS In total, aging mice were characterized by 54 different metabolites when compared to control mice with criteria: VIP ≥ 1, q-value < 0.05, and Fold-Change ≥ 1.2 or ≤0.83. These metabolites were mostly involved in fatty acid biosynthesis, cysteine and methionine metabolism, D-glutamine and D-glutamate metabolism, and the citrate cycle (TCA cycle). We merged the comprehensive analysis and four algorithms (LR, GNB, SVM, and RF) to screen aging-related biomarkers, leading to the recognition of oleic acid. In addition, five metabolites were identified as novel aging-related indicators, including oleic acid, citric acid, D-glutamine, trypophol, and L-methionine. CONCLUSIONS Changes in the metabolism of fatty acids and conjugates, organic acids, and amino acids were identified as metabolic dysregulation related to aging. This study revealed the metabolic profile of aging and provided insights into novel potential therapeutic targets for delaying the effects of aging.
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Affiliation(s)
| | | | | | | | | | - Jianping Weng
- Correspondence: (J.W.); (S.X.); Tel.: +86-0551-63602683 (J.W.)
| | - Suowen Xu
- Correspondence: (J.W.); (S.X.); Tel.: +86-0551-63602683 (J.W.)
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16
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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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17
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Woong Yoo S, Young Kwon S, Kang SR, Min JJ. Molecular imaging approaches to facilitate bacteria-mediated cancer therapy. Adv Drug Deliv Rev 2022; 187:114366. [PMID: 35654213 DOI: 10.1016/j.addr.2022.114366] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 05/06/2022] [Accepted: 05/25/2022] [Indexed: 12/14/2022]
Abstract
Bacteria-mediated cancer therapy is a potential therapeutic strategy for cancer that has unique properties, including broad tumor-targeting ability, various administration routes, the flexibility of delivery, and facilitating the host's immune responses. The molecular imaging of bacteria-mediated cancer therapy allows the therapeutically injected bacteria to be visualized and confirms the accurate delivery of the therapeutic bacteria to the target lesion. Several hurdles make bacteria-specific imaging challenging, including the need to discriminate therapeutic bacterial infection from inflammation or other pathologic lesions. To realize the full potential of bacteria-specific imaging, it is necessary to develop bacteria-specific targets that can be associated with an imaging assay. This review describes the current status of bacterial imaging techniques together with the advantages and disadvantages of several imaging modalities. Also, we describe potential targets for bacterial-specific imaging and related applications.
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Affiliation(s)
- Su Woong Yoo
- Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, Hwasun, Jeonnam, Korea
| | - Seong Young Kwon
- Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, Hwasun, Jeonnam, Korea; Department of Nuclear Medicine, Chonnam National University Medical School, Hwasun, Jeonnam, Korea
| | - Sae-Ryung Kang
- Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, Hwasun, Jeonnam, Korea
| | - Jung-Joon Min
- Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, Hwasun, Jeonnam, Korea; Department of Nuclear Medicine, Chonnam National University Medical School, Hwasun, Jeonnam, Korea.
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18
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Ordonez AA, Parker MF, Miller RJ, Plyku D, Ruiz-Bedoya CA, Tucker EW, Luu JM, Dikeman DA, Lesniak WG, Holt DP, Dannals RF, Miller LS, Rowe SP, Wilson DM, Jain SK. 11C-Para-aminobenzoic acid PET imaging of S. aureus and MRSA infection in preclinical models and humans. JCI Insight 2022; 7:154117. [PMID: 35014627 PMCID: PMC8765043 DOI: 10.1172/jci.insight.154117] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Tools for noninvasive detection of bacterial pathogens are needed but are not currently available for clinical use. We have previously shown that para-aminobenzoic acid (PABA) rapidly accumulates in a wide range of pathogenic bacteria, motivating the development of related PET radiotracers. In this study, 11C-PABA PET imaging was used to accurately detect and monitor infections due to pyogenic bacteria in multiple clinically relevant animal models. 11C-PABA PET imaging selectively detected infections in muscle, intervertebral discs, and methicillin-resistant Staphylococcus aureus–infected orthopedic implants. In what we believe to be first-in-human studies in healthy participants, 11C-PABA was safe, well-tolerated, and had a favorable biodistribution, with low background activity in the lungs, muscles, and brain. 11C-PABA has the potential for clinical translation to detect and localize a broad range of bacteria.
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Affiliation(s)
- Alvaro A Ordonez
- Center for Infection and Inflammation Imaging Research and.,Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Matthew Fl Parker
- Department of Radiology and Biomedical Imaging, UCSF, San Francisco, California, USA
| | | | - Donika Plyku
- Russell H. Morgan Department of Radiology and Radiological Sciences, and
| | - Camilo A Ruiz-Bedoya
- Center for Infection and Inflammation Imaging Research and.,Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Elizabeth W Tucker
- Center for Infection and Inflammation Imaging Research and.,Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Justin M Luu
- Department of Radiology and Biomedical Imaging, UCSF, San Francisco, California, USA
| | | | - Wojciech G Lesniak
- Russell H. Morgan Department of Radiology and Radiological Sciences, and
| | - Daniel P Holt
- Russell H. Morgan Department of Radiology and Radiological Sciences, and
| | - Robert F Dannals
- Russell H. Morgan Department of Radiology and Radiological Sciences, and
| | | | - Steven P Rowe
- Russell H. Morgan Department of Radiology and Radiological Sciences, and
| | - David M Wilson
- Department of Radiology and Biomedical Imaging, UCSF, San Francisco, California, USA
| | - Sanjay K Jain
- Center for Infection and Inflammation Imaging Research and.,Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Russell H. Morgan Department of Radiology and Radiological Sciences, and
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19
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Signore A, Conserva M, Varani M, Galli F, Lauri C, Velikyan I, Roivainen A. PET imaging of bacteria. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00077-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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20
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Rubitschung K, Sherwood A, Crisologo AP, Bhavan K, Haley RW, Wukich DK, Castellino L, Hwang H, La Fontaine J, Chhabra A, Lavery L, Öz OK. Pathophysiology and Molecular Imaging of Diabetic Foot Infections. Int J Mol Sci 2021; 22:11552. [PMID: 34768982 PMCID: PMC8584017 DOI: 10.3390/ijms222111552] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 10/16/2021] [Accepted: 10/20/2021] [Indexed: 12/27/2022] Open
Abstract
Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host's immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections.
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Affiliation(s)
- Katie Rubitschung
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.R.); (A.S.); (A.C.)
| | - Amber Sherwood
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.R.); (A.S.); (A.C.)
| | - Andrew P. Crisologo
- Department of Plastic Surgery, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH 45267-0558, USA;
| | - Kavita Bhavan
- Department of Internal Medicine, Division of Infectious Diseases and Geographic Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.B.); (L.C.)
| | - Robert W. Haley
- Department of Internal Medicine, Epidemiology Division, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA;
| | - Dane K. Wukich
- Department of Orthopedic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA;
| | - Laila Castellino
- Department of Internal Medicine, Division of Infectious Diseases and Geographic Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.B.); (L.C.)
| | - Helena Hwang
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA;
| | - Javier La Fontaine
- Department of Plastic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (J.L.F.); (L.L.)
| | - Avneesh Chhabra
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.R.); (A.S.); (A.C.)
| | - Lawrence Lavery
- Department of Plastic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (J.L.F.); (L.L.)
| | - Orhan K. Öz
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.R.); (A.S.); (A.C.)
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21
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Rubitschung K, Sherwood A, Crisologo AP, Bhavan K, Haley RW, Wukich DK, Castellino L, Hwang H, La Fontaine J, Chhabra A, Lavery L, Öz OK. Pathophysiology and Molecular Imaging of Diabetic Foot Infections. Int J Mol Sci 2021; 22:ijms222111552. [PMID: 34768982 DOI: 10.3390/ijms222111552.pmid:34768982;pmcid:pmc8584017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 10/16/2021] [Accepted: 10/20/2021] [Indexed: 05/27/2023] Open
Abstract
Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host's immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections.
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Affiliation(s)
- Katie Rubitschung
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Amber Sherwood
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Andrew P Crisologo
- Department of Plastic Surgery, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH 45267-0558, USA
| | - Kavita Bhavan
- Department of Internal Medicine, Division of Infectious Diseases and Geographic Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Robert W Haley
- Department of Internal Medicine, Epidemiology Division, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Dane K Wukich
- Department of Orthopedic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Laila Castellino
- Department of Internal Medicine, Division of Infectious Diseases and Geographic Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Helena Hwang
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Javier La Fontaine
- Department of Plastic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Avneesh Chhabra
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Lawrence Lavery
- Department of Plastic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Orhan K Öz
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
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22
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Peukert C, Langer LNB, Wegener SM, Tutov A, Bankstahl JP, Karge B, Bengel FM, Ross TL, Brönstrup M. Optimization of Artificial Siderophores as 68Ga-Complexed PET Tracers for In Vivo Imaging of Bacterial Infections. J Med Chem 2021; 64:12359-12378. [PMID: 34370949 DOI: 10.1021/acs.jmedchem.1c01054] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The diagnosis of bacterial infections at deep body sites benefits from noninvasive imaging of molecular probes that can be traced by positron emission tomography (PET). We specifically labeled bacteria by targeting their iron transport system with artificial siderophores. The cyclen-based probes contain different binding sites for iron and the PET nuclide gallium-68. A panel of 11 siderophores with different iron coordination numbers and geometries was synthesized in up to 8 steps, and candidates with the best siderophore potential were selected by a growth recovery assay. The probes [68Ga]7 and [68Ga]15 were found to be suitable for PET imaging based on their radiochemical yield, radiochemical purity, and complex stability in vitro and in vivo. Both showed significant uptake in mice infected with Escherichia coli and were able to discern infection from lipopolysaccharide-triggered, sterile inflammation. The study qualifies cyclen-based artificial siderophores as readily accessible scaffolds for the in vivo imaging of bacteria.
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Affiliation(s)
- Carsten Peukert
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
| | - Laura N B Langer
- Department of Nuclear Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Sophie M Wegener
- Department of Nuclear Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Anna Tutov
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
| | - Jens P Bankstahl
- Department of Nuclear Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Bianka Karge
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
| | - Frank M Bengel
- Department of Nuclear Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Tobias L Ross
- Department of Nuclear Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Mark Brönstrup
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
- German Center for Infection Research (DZIF), Site Hannover-Braunschweig, 38124 Braunschweig, Germany
- Center for Biomolecular Drug Research (BMWZ), Schneiderberg 38, 30167 Hannover, Germany
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23
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Synthesis and Evaluation of Novel Norfloxacin Isonitrile 99mTc Complexes as Potential Bacterial Infection Imaging Agents. Pharmaceutics 2021; 13:pharmaceutics13040518. [PMID: 33918583 PMCID: PMC8069222 DOI: 10.3390/pharmaceutics13040518] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 11/17/2022] Open
Abstract
To develop potential technetium-99m single-photon emission computed tomography (SPECT) imaging agents for bacterial infection imaging, the novel norfloxacin isonitrile derivatives CN4NF and CN5NF were synthesized and radiolabeled with a [99mTc][Tc(I)]+ core to obtain [99mTc]Tc-CN4NF and [99mTc]Tc-CN5NF. These compounds were produced in high radiolabeling yields and showed hydrophilicity and good stability in vitro. The bacterial binding assay indicated that [99mTc]Tc-CN4NF and [99mTc]Tc-CN5NF were specific to bacteria. Compared with [99mTc]Tc-CN4NF, biodistribution studies of [99mTc]Tc-CN5NF showed a higher uptake in bacteria-infected tissues than in turpentine-induced abscesses, indicating that [99mTc]Tc-CN5NF could distinguish bacterial infection from sterile inflammation. In addition, [99mTc]Tc-CN5NF had higher abscess/blood and abscess/muscle ratios. SPECT image of [99mTc]Tc-CN5NF showed that there was a clear accumulation in the infection site, suggesting that it could be a potential bacterial infection imaging radiotracer.
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24
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Ordoñez AA, Jain SK. Imaging of Bacterial Infections. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00089-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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