1
|
KETO[ 18F]FDG -VAP-P1: In vivo studies of a potential PET radiotracer for diagnosis of inflammation. Appl Radiat Isot 2023; 192:110547. [PMID: 36470157 DOI: 10.1016/j.apradiso.2022.110547] [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: 08/15/2022] [Revised: 10/25/2022] [Accepted: 10/27/2022] [Indexed: 11/08/2022]
Abstract
The biodistribution of radiotracer peptide KETO[18F]FDG-VAP-P1 was evaluated by ex vivo radiation count in organs and in vivo PET imaging of healthy mice. The peptide was quickly eliminated by the kidneys. The local inflammation caused by a sterile polyurethane sponge was evaluated by PET images. In addition, dosimetry estimates of KETO[18F]FDG-VAP-P1 tracer are determined for mice using Monte Carlo simulations. Thus, the results of this study indicate that KETO[18F]FDG-VAP-P1 is a potential radiotracer for inflammation imaging.
Collapse
|
2
|
Feng L, Fang J, Zeng X, Liu H, Zhang J, Huang L, Guo Z, Zhuang R, Zhang X. 68Ga-Labeled Maleimide for Blood Pool and Lymph PET Imaging through Covalent Bonding to Serum Albumin In Vivo. ACS OMEGA 2022; 7:28597-28604. [PMID: 35990434 PMCID: PMC9386703 DOI: 10.1021/acsomega.2c03505] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
This study aims to develop a novel 68Ga-labeled tracer, which can covalently bind to albumin in vivo based on the maleimide-thiol strategy, and to evaluate its potential applications using positron emission tomography (PET). 68Ga-labeled maleimide-monoamide-DOTA (denoted as [68Ga]Ga-DM) was prepared conveniently with a high radiochemical yield (>90%) and radiochemical purity (>99%). Its molar activity was calculated as 249.60 ± 68.50 GBq/μmol, and the octanol-water partition coefficient (LogP) was -3.15 ± 0.08 with good stabilities. In vitro experiments showed that [68Ga]Ga-DM can bind to albumin efficiently and rapidly, with a binding fraction of over 70%. High uptake and excellent retention in blood were observed with a long half-life (t 1/2Z) of 190.15 ± 24.14 min, which makes it possible for blood pool PET imaging with high contrast. The transient micro-bleeding in the rat model was detected successfully with PET imaging. In addition, the uptakes of [68Ga]Ga-DM in the inflammatory popliteal lymph nodes depend on the severity (5.90% ID/g and 2.32% ID/g vs 1.01% ID/g for healthy lymph nodes at 0.5 h post-injection) indicating its feasibility for lymphatic imaging. In conclusion, a novel 68Ga-labeled tracer was prepared with high efficiency and yield in mild conditions. Based on the promising properties of bonding covalently to albumin, great stability, high blood contrast with a long half-life, and well environmental tolerance, [68Ga]Ga-DM could be developed as a potential tracer for PET imaging of blood pool, bleeding, and vascular permeability alteration diseases in the clinic.
Collapse
|
3
|
More S, Marakalala MJ, Sathekge M. Tuberculosis: Role of Nuclear Medicine and Molecular Imaging With Potential Impact of Neutrophil-Specific Tracers. Front Med (Lausanne) 2021; 8:758636. [PMID: 34957144 PMCID: PMC8703031 DOI: 10.3389/fmed.2021.758636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 11/03/2021] [Indexed: 01/02/2023] Open
Abstract
With Tuberculosis (TB) affecting millions of people worldwide, novel imaging modalities and tools, particularly nuclear medicine and molecular imaging, have grown with greater interest to assess the biology of the tuberculous granuloma and evolution thereof. Much early work has been performed at the pre-clinical level using gamma single photon emission computed tomography (SPECT) agents exploiting certain characteristics of Mycobacterium tuberculosis (MTb). Both antituberculous SPECT and positron emission tomography (PET) agents have been utilised to characterise MTb. Other PET tracers have been utilised to help to characterise the biology of MTb (including Gallium-68-labelled radiopharmaceuticals). Of all the tracers, 2-[18F]FDG has been studied extensively over the last two decades in many aspects of the treatment paradigm of TB: at diagnosis, staging, response assessment, restaging, and in potentially predicting the outcome of patients with latent TB infection. Its lower specificity in being able to distinguish different inflammatory cell types in the granuloma has garnered interest in reviewing more specific agents that can portend prognostic implications in the management of MTb. With the neutrophil being a cell type that portends this poorer prognosis, imaging this cell type may be able to answer more accurately questions relating to the tuberculous granuloma transmissivity and may help in characterising patients who may be at risk of developing active TB. The formyl peptide receptor 1(FPR1) expressed by neutrophils is a key marker in this process and is a potential target to characterise these areas. The pre-clinical work regarding the role of radiolabelled N-cinnamoyl –F-(D) L – F – (D) –L F (cFLFLF) (which is an antagonist for FPR1) using Technetium 99m-labelled conjugates and more recently radiolabelled with Gallium-68 and Copper 64 is discussed. It is the hope that further work with this tracer may accelerate its potential to be utilised in responding to many of the current diagnostic dilemmas and challenges in TB management, thereby making the tracer a translatable option in routine clinical care.
Collapse
Affiliation(s)
- Stuart More
- Division of Nuclear Medicine, Department of Radiation Medicine, University of Cape Town, Cape Town, South Africa
- Department of Nuclear Medicine, University of Pretoria and Steve Biko Academic Hospital, Pretoria, South Africa
- Nuclear Medicine Research Infrastructure, Steve Biko Academic Hospital, Pretoria, South Africa
- *Correspondence: Stuart More
| | - Mohlopheni J. Marakalala
- Africa Health Research Institute, Durban, South Africa
- Division of Infection and Immunity, University College London, London, United Kingdom
- School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
- Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Michael Sathekge
- Department of Nuclear Medicine, University of Pretoria and Steve Biko Academic Hospital, Pretoria, South Africa
- Nuclear Medicine Research Infrastructure, Steve Biko Academic Hospital, Pretoria, South Africa
| |
Collapse
|
4
|
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
|
5
|
Kumar P, Tripathi SK, Chen CP, Wickstrom E, Thakur ML. Evaluating Ga-68 Peptide Conjugates for Targeting VPAC Receptors: Stability and Pharmacokinetics. Mol Imaging Biol 2019; 21:130-139. [PMID: 29802552 DOI: 10.1007/s11307-018-1207-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE In recent years, considerable progress has been made in the use of gallium-68 labeled receptor-specific peptides for imaging oncologic diseases. The objective was to examine the stability and pharmacokinetics of [68Ga]NODAGA and DOTA-peptide conjugate targeting VPAC [combined for vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating peptide (PACAP)] receptors on tumor cells. PROCEDURES A VPAC receptor-specific peptide was chosen as a model peptide and conjugated to NODAGA and DOTA via solid-phase synthesis. The conjugates were characterized by HPLC and MALDI-TOF. Following Ga-68 chelation, the radiochemical purity of Ga-68 labeled peptide conjugate was determined by radio-HPLC. The stability was tested against transmetallation using 100 nM Fe3+/Zn2+/Ca2+ ionic solution and against transchelation using 200 μM DTPA solution. The ex vivo and in vivo stability of the Ga-68 labeled peptide conjugate was tested in mouse plasma and urine. Receptor specificity was determined ex vivo by cell binding assays using human breast cancer BT474 cells. Positron emission tomography (PET)/X-ray computed tomography (CT) imaging, tissue distribution, and blocking studies were performed in mice bearing BT474 xenografts. RESULTS The chemical and radiochemical purity was greater than 95 % and both conjugates were stable against transchelation and transmetallation. Ex vivo stability at 60 min showed that the NODAGA-peptide-bound Ga-68 reduced to 42.1 ± 3.7 % (in plasma) and 37.4 ± 2.9 % (in urine), whereas the DOTA-peptide-bound Ga-68 was reduced to 1.2 ± 0.3 % (in plasma) and 4.2 ± 0.4 % (in urine) at 60 min. Similarly, the in vivo stability for [68Ga]NODAGA-peptide was decreased to 2.1 ± 0.2 % (in plasma) and 2.2 ± 0.4 % (in urine). For [68Ga]DOTA-peptide, it was decreased to 1.4 ± 0.3 % (in plasma) and 1.2 ± 0.4 % (in urine) at 60 min. The specific BT474 cell binding was 53.9 ± 0.8 % for [68Ga]NODAGA-peptide, 25.8 ± 1.4 % for [68Ga]-DOTA-peptide, and 18.8 ± 2.5 % for [68Ga]GaCl3 at 60 min. Inveon microPET/CT imaging at 1 h post-injection showed significantly (p < 0.05) higher tumor to muscle (T/M) ratio for [68Ga]NODAGA-peptide (3.4 ± 0.3) as compared to [68Ga]DOTA-peptide (1.8 ± 0.6). For [68Ga]GaCl3 and blocked mice, their ratios were 1.5 ± 0.6 and 1.5 ± 0.3 respectively. The tissue distributions data were similar to the PET imaging data. CONCLUSION NODAGA is superior to DOTA in terms of radiolabeling kinetics. The method of radiolabeling was reproducible and yielded higher specific activity. Although both agents have relatively low in vivo stability, PET/CT imaging studies delineated BC tumors with [68Ga]NODAGA-peptide, but not with [68Ga]DOTA-peptide.
Collapse
Affiliation(s)
- Pardeep Kumar
- Departments of Radiology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Sushil K Tripathi
- Departments of Radiology, Thomas Jefferson University, Philadelphia, PA, USA
| | - C P Chen
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, China
| | - Eric Wickstrom
- Departments of Biochemistry & Molecular Biology, Thomas Jefferson University, Philadelphia, PA, USA.,Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Mathew L Thakur
- Departments of Radiology, Thomas Jefferson University, Philadelphia, PA, USA. .,Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA. .,Departments of Radiation Oncology, Thomas Jefferson University, 1020 Locust Street, JAH Suite 359, Philadelphia, PA, 19107, USA. .,Departments of Urology, Thomas Jefferson University, Philadelphia, PA, USA.
| |
Collapse
|
6
|
Ordonez AA, Jain SK. Pathogen-Specific Bacterial Imaging in Nuclear Medicine. Semin Nucl Med 2018. [DOI: 10.1053/j.semnuclmed.2017.11.003
expr 890398765 + 809902709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
|
7
|
Abstract
When serious infections are suspected, patients are often treated empirically with broad-spectrum antibiotics while awaiting results that provide information on the bacterial class and species causing the infection, as well as drug susceptibilities. For deep-seated infections, these traditional diagnostic techniques often rely on tissue biopsies to obtain clinical samples which can be expensive, dangerous, and has the potential of sampling bias. Moreover, these procedures and results can take several days and may not always provide reliable information. This combination of time and effort required for proper antibiotic selection has become a barrier leading to indiscriminate broad-spectrum antibiotic use. Exposure to nosocomial infections and indiscriminate use of broad-spectrum antibiotics are responsible for promoting bacterial drug-resistance leading to substantial morbidity and mortality, especially in hospitalized and immunosuppressed patients. Therefore, early diagnosis of infection and targeted antibiotic treatments are urgently needed to reduce morbidity and mortality caused by bacterial infections worldwide. Reliable pathogen-specific bacterial imaging techniques have the potential to provide early diagnosis and guide antibiotic treatments.
Collapse
Affiliation(s)
- Alvaro A Ordonez
- Center for Infection and Inflammation Imaging Research, Johns Hopkins University School of Medicine, Baltimore, MD; Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Sanjay K Jain
- Center for Infection and Inflammation Imaging Research, Johns Hopkins University School of Medicine, Baltimore, MD; Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD.
| |
Collapse
|
8
|
Mapping the interaction site and effect of the Siglec-9 inflammatory biomarker on human primary amine oxidase. Sci Rep 2018; 8:2086. [PMID: 29391504 PMCID: PMC5794975 DOI: 10.1038/s41598-018-20618-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 01/22/2018] [Indexed: 12/21/2022] Open
Abstract
Human primary amine oxidase (hAOC3), also known as vascular adhesion protein 1, mediates leukocyte rolling and trafficking to sites of inflammation by a multistep adhesion cascade. hAOC3 is absent on the endothelium of normal tissues and is kept upregulated during inflammatory conditions, which is an applicable advantage for imaging inflammatory diseases. Sialic acid binding immunoglobulin like-lectin 9 (Siglec-9) is a leukocyte ligand for hAOC3. The peptide (CARLSLSWRGLTLCPSK) based on the region of Siglec-9 that interacts with hAOC3, can be used as a specific tracer for hAOC3-targeted imaging of inflammation using Positron Emission Tomography (PET). In the present study, we show that the Siglec-9 peptide binds to hAOC3 and triggers its amine oxidase activity towards benzylamine. Furthermore, the hAOC3 inhibitors semicarbazide and imidazole reduce the binding of wild type and Arg/Ala mutated Siglec-9 peptides to hAOC3. Molecular docking of the Siglec-9 peptide is in accordance with the experimental results and predicts that the R3 residue in the peptide interacts in the catalytic site of hAOC3 when the topaquinone cofactor is in the non-catalytic on-copper conformation. The predicted binding mode of Siglec-9 peptide to hAOC3 is supported by the PET studies using rodent, rabbit and pig AOC3 proteins.
Collapse
|
9
|
Prospective of 68Ga Radionuclide Contribution to the Development of Imaging Agents for Infection and Inflammation. CONTRAST MEDIA & MOLECULAR IMAGING 2018. [PMID: 29531507 PMCID: PMC5817300 DOI: 10.1155/2018/9713691] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
During the last decade, the utilization of 68Ga for the development of imaging agents has increased considerably with the leading position in the oncology. The imaging of infection and inflammation is lagging despite strong unmet medical needs. This review presents the potential routes for the development of 68Ga-based agents for the imaging and quantification of infection and inflammation in various diseases and connection of the diagnosis to the treatment for the individualized patient management.
Collapse
|
10
|
Siitonen R, Pietikäinen A, Liljenbäck H, Käkelä M, Söderström M, Jalkanen S, Hytönen J, Roivainen A. Targeting of vascular adhesion protein-1 by positron emission tomography visualizes sites of inflammation in Borrelia burgdorferi-infected mice. Arthritis Res Ther 2017; 19:254. [PMID: 29166944 PMCID: PMC5700622 DOI: 10.1186/s13075-017-1460-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 10/26/2017] [Indexed: 12/13/2022] Open
Abstract
Background In the present study, we sought to evaluate the feasibility of targeting vascular adhesion protein-1 (VAP-1) by positron emission tomography (PET) for the longitudinal quantitative assessment of Borrelia burgdorferi infection-induced inflammation in mice. Methods Mice with B. burgdorferi infection-induced arthritis were studied. During a 7-week follow-up period, the progression of arthritis was monitored weekly with 68Ga-DOTA-Siglec-9 PET/computed tomography (CT) and measurement of tibiotarsal joint swellings. A subgroup of infected mice was treated with ceftriaxone. Finally, histopathological assessment of joint inflammation was performed and VAP-1 expression in joints were determined. Results Explicit joint swelling and 68Ga-DOTA-Siglec-9 uptake could be demonstrated in the affected joints from B. burgdorferi-infected mice. By contrast, no obvious accumulation of 68Ga-DOTA-Siglec-9 was detected in joints of uninfected mice. The maximum swelling and highest uptake in the affected joints were observed 4 weeks after the infection. 68Ga-DOTA-Siglec-9 uptake in joints correlated with joint swelling (P < 0.0001) and histopathological scoring of inflammation (P = 0.020). Despite short-term antibiotic treatment, the arthritis persisted, and the PET signal remained as high as in nontreated mice. Immunohistochemistry revealed strong-to-moderate expression of VAP-1 in the synovium of B. burgdorferi-infected mice, while only weak expression of VAP-1 was detected in uninfected mice. Conclusions The present study showed that 68Ga-DOTA-Siglec-9 can detect B. burgdorferi infection-induced arthritis in mice. Furthermore, longitudinal PET/CT imaging allowed monitoring of arthritis development over time.
Collapse
Affiliation(s)
- Riikka Siitonen
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, FI-20520, Turku, Finland
| | - Annukka Pietikäinen
- Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FI-20520, Turku, Finland.,Turku Doctoral Programme for Molecular Medicine, Turku, Finland
| | - Heidi Liljenbäck
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, FI-20520, Turku, Finland.,Turku Center for Disease Modeling, University of Turku, Kiinamyllynkatu 10, FI-20520, Turku, Finland
| | - Meeri Käkelä
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, FI-20520, Turku, Finland
| | - Mirva Söderström
- Department of Pathology, Turku University Hospital, Kiinamyllynkatu 10, FI-20520, Turku, Finland
| | - Sirpa Jalkanen
- Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FI-20520, Turku, Finland.,MediCity Research Laboratory, University of Turku, Tykistönkatu 6, FI-20520, Turku, Finland
| | - Jukka Hytönen
- Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FI-20520, Turku, Finland.,Microbiology and Genetics Department, Turku University Hospital, Kiinamyllynkatu 10, FI-20520, Turku, Finland
| | - Anne Roivainen
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, FI-20520, Turku, Finland. .,Turku Center for Disease Modeling, University of Turku, Kiinamyllynkatu 10, FI-20520, Turku, Finland. .,Turku PET Centre, Turku University Hospital, Kiinamyllynkatu 4-8, FI-20520, Turku, Finland.
| |
Collapse
|
11
|
Preclinical Assessment of a 68Ga-DOTA-Functionalized Depsipeptide as a Radiodiagnostic Infection Imaging Agent. Molecules 2017; 22:molecules22091403. [PMID: 28837117 PMCID: PMC6151697 DOI: 10.3390/molecules22091403] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 08/18/2017] [Indexed: 11/16/2022] Open
Abstract
The study assessed a radiolabeled depsipeptide conjugate (68Ga-DOTA-TBIA101) for its potential as an imaging agent targeting infection or infection-associated inflammation. 68Ga-labeled DOTA-TBIA101 imaging was performed in (NZR1) healthy rabbits; (NZR2) rabbits bearing muscular sterile inflammation and Staphylococcus aureus (SA) infection; and (NZR3) rabbits infected with Mycobacterium tuberculosis (MTB) combined with a subcutaneous scruff infection of SA in the same animal. All animals were imaged using a PET/CT scanner at 5 and 60 min post injection. Images showed elevated accumulation of 68Ga-DOTA-TBIA101 in the sterile muscular inflammation site (T/NT ratio = 2.6 ± 0.37 (5 min) and 2.8 ± 2.3 (60 min)) and muscles infected with MTB (T/NT ratio = 2.6 ± 0.35 (5 min) and 2.8 ± 0.16 (60 min)). The findings suggest that 68Ga-DOTA-TBIA101-PET/CT may detect MTB-associated inflammation, although more foundational studies need to be performed to rationalize the diagnostic value of this technique.
Collapse
|
12
|
Jensen SB, Käkelä M, Jødal L, Moisio O, Alstrup AKO, Jalkanen S, Roivainen A. Exploring the radiosynthesis and in vitro characteristics of [ 68 Ga]Ga-DOTA-Siglec-9. J Labelled Comp Radiopharm 2017; 60:439-449. [PMID: 28556976 DOI: 10.1002/jlcr.3525] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 05/04/2017] [Accepted: 05/23/2017] [Indexed: 12/12/2022]
Abstract
Vascular adhesion protein 1 is a leukocyte homing-associated glycoprotein, which upon inflammation rapidly translocates from intracellular sources to the endothelial cell surface. It has been discovered that the cyclic peptide residues 283-297 of sialic acid-binding IgG-like lectin 9 (Siglec-9) "CARLSLSWRGLTLCPSK" bind to vascular adhesion protein 1 and hence makes the radioactive analogues of this compound ([68 Ga]Ga-DOTA-Siglec-9) interesting as a noninvasive visualizing marker of inflammation. Three different approaches to the radiosynthesis of [68 Ga]Ga-DOTA-Siglec-9 are presented and compared with previously published methods. A simple, robust radiosynthesis of [68 Ga]Ga-DOTA-Siglec-9 with a yield of 62% (non decay-corrected) was identified, and it had a radiochemical purity >98% and a specific radioactivity of 35 MBq/nmol. Furthermore, the protein binding and stability of [68 Ga]Ga-DOTA-Siglec-9 were analyzed in vitro in mouse, rat, rabbit, pig, and human plasma and compared with in vivo pig results. The plasma in vitro protein binding of [68 Ga]Ga-DOTA-Siglec-9 was the lowest in the pig followed by rabbit, human, rat, and mouse. It was considerably higher in the in vivo pig experiments. The in vivo stability in pigs was lower than the in vitro stability. Despite considerable species differences, the observed characteristics of [68 Ga]Ga-DOTA-Siglec-9 are suitable as a positron emission tomography tracer.
Collapse
Affiliation(s)
- Svend B Jensen
- Department of Nuclear Medicine, Aalborg University Hospital, Denmark.,Department of Chemistry and Biosciences, Aalborg University, Aalborg, Denmark
| | - Meeri Käkelä
- Turku PET Centre, University of Turku, Turku, Finland
| | - Lars Jødal
- Department of Nuclear Medicine, Aalborg University Hospital, Denmark.,Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Aarhus, Denmark.,Department of Veterinary Disease Biology, University of Copenhagen, Copenhagen, Denmark
| | - Olli Moisio
- Turku PET Centre, University of Turku, Turku, Finland
| | - Aage K O Alstrup
- Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Sirpa Jalkanen
- MediCity Research Laboratory and Department of Medical Microbiology and Immunology, University of Turku, Turku, Finland
| | - Anne Roivainen
- Turku PET Centre, University of Turku, Turku, Finland.,Turku PET Centre, Turku University Hospital, Turku, Finland.,Turku Centre for Disease Modelling, University of Turku, Turku, Finland
| |
Collapse
|
13
|
Lee JY, Lee SY, Kim GG, Hur MG, Yang SD, Park JH, Kim SW. Development of 68Ga-SCN-DOTA-Capsaicin as an Imaging Agent Targeting Apoptosis and Cell Cycle Arrest in Breast Cancer. Cancer Biother Radiopharm 2017; 32:169-175. [PMID: 28598691 DOI: 10.1089/cbr.2017.2186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
68Ga-labeled capsaicin using a DOTA (1,4,7,10-tetraazocyclododecane-N,N',N″,N'″-tetraacetic acid) derivative [68Ga-SCN-Benzyl(Bn)-DOTA-capsaicin] was studied for the diagnosis of breast cancers, such as MCF-7 and SK-BR-3. The standard compound, 69Ga-SCN-Bn-DOTA-capsaicin, was also prepared and characterized by spectroscopic analysis. The binding affinity of 68Ga-SCN-Bn-DOTA-capsaicin was evaluated by using breast cancer cell lines (MCF-7, SK-BR-3) and colon cancer cell (CT-26); the biodistribution was carried out by using MCF-7-bearing nude mice, after which the positron emission tomography (PET) images were obtained at different time intervals (15-120 minutes). 68Ga-SCN-Bn-DOTA-capsaicin showed a cellular uptake of 0.93% Injected Dose (ID) after 30 minutes of incubation, whereas 68Ga-SCN-Bn-DOTA showed a lower uptake of 0.25% ID. The tumor-to-blood ID/g% ratios increased and were found to be 0.49, 0.22, and 0.77 for 15, 30, and 60 minutes, respectively. The small-animal PET study showed that the uptake of 68Ga-SCN-Bn-DOTA-capsaicin was higher in the tumor regions even at 30 minutes after injection. These results suggest that 68Ga-SCN-Bn-DOTA-capsaicin is a potential targeting agent for PET imaging of MCF-7.
Collapse
Affiliation(s)
- Jun Young Lee
- 1 Radiation Instrumentation Research Division, Korea Atomic Energy Research Institute , Jeongeup, Republic of Korea
| | - Sang-Yeun Lee
- 1 Radiation Instrumentation Research Division, Korea Atomic Energy Research Institute , Jeongeup, Republic of Korea
| | - Gun Gyun Kim
- 1 Radiation Instrumentation Research Division, Korea Atomic Energy Research Institute , Jeongeup, Republic of Korea.,2 Department of Advanced Materials Chemistry, College of Science and Technology, Dongguk University , Gyeongju, Republic of Korea
| | - Min Goo Hur
- 1 Radiation Instrumentation Research Division, Korea Atomic Energy Research Institute , Jeongeup, Republic of Korea
| | - Seung Dae Yang
- 1 Radiation Instrumentation Research Division, Korea Atomic Energy Research Institute , Jeongeup, Republic of Korea
| | - Jeong-Hoon Park
- 1 Radiation Instrumentation Research Division, Korea Atomic Energy Research Institute , Jeongeup, Republic of Korea
| | - Sang Wook Kim
- 2 Department of Advanced Materials Chemistry, College of Science and Technology, Dongguk University , Gyeongju, Republic of Korea
| |
Collapse
|
14
|
Virtanen H, Autio A, Siitonen R, Liljenbäck H, Saanijoki T, Lankinen P, Mäkilä J, Käkelä M, Teuho J, Savisto N, Jaakkola K, Jalkanen S, Roivainen A. 68Ga-DOTA-Siglec-9--a new imaging tool to detect synovitis. Arthritis Res Ther 2015; 17:308. [PMID: 26530096 PMCID: PMC4632466 DOI: 10.1186/s13075-015-0826-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 09/15/2015] [Indexed: 11/15/2022] Open
Abstract
Introduction Vascular adhesion protein-1 (VAP-1) is an adhesion molecule, which upon inflammation is rapidly translocated from intracellular sources to the endothelial cell surface. We have recently discovered that sialic acid- binding immunoglobulin-like lectin 9 (Siglec-9) is a leukocyte ligand of VAP-1 and that 68Ga-labeled Siglec-9 motif peptide facilitates in vivo imaging of inflammation. This study evaluated the feasibility of 68Ga-DOTA-Siglec-9 positron emission tomography (PET) for the assessment of synovitis. Methods Rabbits with synovial inflammation were injected with 18F-FDG or 68Ga-DOTA-Siglec-9 and studied by gamma counting and autoradiography. Certain rabbits were also examined with magnetic resonance imaging (MRI). After PET imaging, rabbits were intravenously administered with anti-VAP-1 antibody to evaluate luminal expression of VAP-1 by immunohistochemistry. Finally, binding of Siglec-9 peptide and VAP-1 positive vessels were evaluated by double staining of rheumatoid arthritis synovium. Results Intra-articular injection of hemagglutinin induced mild synovial inflammation in rabbit knee with luminal expression of VAP-1. Synovitis was clearly visualized by 68Ga-DOTA-Siglec-9 PET in addition to 18F-FDG-PET and MRI. Compared with the 18F-FDG, the ex vivo inflamed-to-control synovium ratio of 68Ga-DOTA-Siglec-9 was similar (1.7 ± 0.4 vs. 1.5 ± 0.2, P = 0.32). Double staining revealed that Siglec-9 peptide binds to VAP-1 positive vessels in human rheumatoid synovium. Conclusion Ga-DOTA-Siglec-9 PET tracer detected VAP-1 positive vasculature in the mild synovitis of rabbits comparable with 18F-FDG, suggesting its potential for in vivo imaging of synovial inflammation in patients with rheumatic diseases.
Collapse
Affiliation(s)
- Helena Virtanen
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland.
| | - Anu Autio
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland.
| | - Riikka Siitonen
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland.
| | - Heidi Liljenbäck
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland. .,Turku Center for Disease Modeling, University of Turku, Turku, Finland.
| | - Tiina Saanijoki
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland.
| | - Petteri Lankinen
- Department of Orthopaedic Surgery and Traumatology, University of Turku, Turku, Finland.
| | - Jussi Mäkilä
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland. .,Department of Cell Biology and Anatomy, University of Turku, Turku, Finland.
| | - Meeri Käkelä
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland.
| | - Jarmo Teuho
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland.
| | - Nina Savisto
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland.
| | - Kimmo Jaakkola
- VTT Technical Research Centre of Finland, Medical Biotechnology, Turku, Finland.
| | - Sirpa Jalkanen
- MediCity Research Laboratory, University of Turku, Turku, Finland.
| | - Anne Roivainen
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, FI-20521, Finland. .,Turku Center for Disease Modeling, University of Turku, Turku, Finland.
| |
Collapse
|
15
|
Synthesis, 68Ga-radiolabeling, and preliminary in vivo assessment of a depsipeptide-derived compound as a potential PET/CT infection imaging agent. BIOMED RESEARCH INTERNATIONAL 2015; 2015:284354. [PMID: 25699267 PMCID: PMC4324493 DOI: 10.1155/2015/284354] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Revised: 07/28/2014] [Accepted: 08/05/2014] [Indexed: 11/21/2022]
Abstract
Noninvasive imaging is a powerful tool for early diagnosis and monitoring of various disease processes, such as infections. An alarming shortage of infection-selective radiopharmaceuticals exists for overcoming the diagnostic limitations with unspecific tracers such as 67/68Ga-citrate or 18F-FDG. We report here TBIA101, an antimicrobial peptide derivative that was conjugated to DOTA and radiolabeled with 68Ga for a subsequent in vitro assessment and in vivo infection imaging using Escherichia coli-bearing mice by targeting bacterial lipopolysaccharides with PET/CT. Following DOTA-conjugation, the compound was verified for its cytotoxic and bacterial binding behaviour and compound stability, followed by 68Gallium-radiolabeling. µPET/CT using 68Ga-DOTA-TBIA101 was employed to detect muscular E. coli-infection in BALB/c mice, as warranted by the in vitro results. 68Ga-DOTA-TBIA101-PET detected E. coli-infected muscle tissue (SUV = 1.3–2.4) > noninfected thighs (P = 0.322) > forearm muscles (P = 0.092) > background (P = 0.021) in the same animal. Normalization of the infected thigh muscle to reference tissue showed a ratio of 3.0 ± 0.8 and a ratio of 2.3 ± 0.6 compared to the identical healthy tissue. The majority of the activity was cleared by renal excretion. The latter findings warrant further preclinical imaging studies of greater depth, as the DOTA-conjugation did not compromise the TBIA101's capacity as targeting vector.
Collapse
|
16
|
Hong H, Chen F, Zhang Y, Cai W. New radiotracers for imaging of vascular targets in angiogenesis-related diseases. Adv Drug Deliv Rev 2014; 76:2-20. [PMID: 25086372 DOI: 10.1016/j.addr.2014.07.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Revised: 07/14/2014] [Accepted: 07/22/2014] [Indexed: 01/03/2023]
Abstract
Tremendous advances over the last several decades in positron emission tomography (PET) and single photon emission computed tomography (SPECT) allow for targeted imaging of molecular and cellular events in the living systems. Angiogenesis, a multistep process regulated by the network of different angiogenic factors, has attracted world-wide interests, due to its pivotal role in the formation and progression of different diseases including cancer, cardiovascular diseases (CVD), and inflammation. In this review article, we will summarize the recent progress in PET or SPECT imaging of a wide variety of vascular targets in three major angiogenesis-related diseases: cancer, cardiovascular diseases, and inflammation. Faster drug development and patient stratification for a specific therapy will become possible with the facilitation of PET or SPECT imaging and it will be critical for the maximum benefit of patients.
Collapse
|
17
|
Ahtinen H, Kulkova J, Lindholm L, Eerola E, Hakanen AJ, Moritz N, Söderström M, Saanijoki T, Jalkanen S, Roivainen A, Aro HT. (68)Ga-DOTA-Siglec-9 PET/CT imaging of peri-implant tissue responses and staphylococcal infections. EJNMMI Res 2014; 4:45. [PMID: 25520903 PMCID: PMC4265888 DOI: 10.1186/s13550-014-0045-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 07/26/2014] [Indexed: 11/16/2022] Open
Abstract
Background Staphylococcus epidermidis (S. epidermidis) has emerged as one of the leading pathogens of biomaterial-related infections. Vascular adhesion protein-1 (VAP-1) is an inflammation-inducible endothelial molecule controlling extravasation of leukocytes. Sialic acid-binding immunoglobulin-like lectin 9 (Siglec-9) is a leukocyte ligand of VAP-1. We hypothesized that 68Ga-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-conjugated Siglec-9 motif containing peptide (68Ga-DOTA-Siglec-9) could detect inflammatory response due to S. epidermidis peri-implant infection by positron emission tomography (PET). Methods Thirty Sprague-Dawley rats were randomized into three groups. A sterile catheter was implanted into the medullary canal of the left tibia. In groups 1 and 2, the implantation was followed by peri-implant injection of S. epidermidis or Staphylococcus aureus (S. aureus) with adjunct injections of aqueous sodium morrhuate. In group 3, sterile saline was injected instead of bacteria and no aqueous sodium morrhuate was used. At 2 weeks after operation, 68Ga-DOTA-Siglec-9 PET coupled with computed tomography (CT) was performed with the measurement of the standardized uptake value (SUV). The presence of the implant-related infection was verified by microbiological analysis, imaging with fluorescence microscope, and histology. The in vivo PET results were verified by ex vivo measurements by gamma counter. Results In group 3, the tibias with implanted sterile catheters showed an increased local uptake of 68Ga-DOTA-Siglec-9 compared with the intact contralateral bones (SUVratio +29.5%). 68Ga-DOTA-Siglec-9 PET detected inflammation induced by S. epidermidis and S. aureus catheter-related bone infections (SUVratio +58.1% and +41.7%, respectively). The tracer uptake was significantly higher in the S. epidermidis group than in group 3 without bacterial inoculation, but the difference between S. epidermidis and S. aureus groups was not statistically significant. The difference between the S. aureus group and group 3 was neither statistically significant. Conclusion PET/CT imaging with novel 68Ga-DOTA-Siglec-9 tracer was able to detect inflammatory tissue response induced by catheter implantation and staphylococcal infections.
Collapse
Affiliation(s)
- Helena Ahtinen
- Turku PET Centre, Turku University Hospital, University of Turku, Turku FI-20521, Finland
| | - Julia Kulkova
- Orthopaedic Research Unit, Department of Orthopaedic Surgery and Traumatology, Turku University Hospital, University of Turku, Turku FI-20521, Finland
| | - Laura Lindholm
- Department of Medical Microbiology and Immunology, University of Turku, Turku FI-20521, Finland
| | - Erkki Eerola
- Department of Medical Microbiology and Immunology, University of Turku, Turku FI-20521, Finland
| | - Antti J Hakanen
- Antimicrobial Resistance Unit, National Institute for Health and Welfare, Turku FI-20521, Finland
| | - Niko Moritz
- Turku Clinical Biomaterials Centre, Institute of Dentistry, University of Turku, Turku FI-20521, Finland
| | - Mirva Söderström
- Department of Pathology, Turku University Hospital, University of Turku, Turku FI-20521, Finland
| | - Tiina Saanijoki
- Turku PET Centre, Turku University Hospital, University of Turku, Turku FI-20521, Finland
| | - Sirpa Jalkanen
- Department of Medical Microbiology and Immunology, University of Turku, Turku FI-20521, Finland ; MediCity Research Laboratory, University of Turku, Turku FI-20521, Finland
| | - Anne Roivainen
- Turku PET Centre, Turku University Hospital, University of Turku, Turku FI-20521, Finland ; Turku Center for Disease Modeling, University of Turku, Turku FI-20521, Finland
| | - Hannu T Aro
- Orthopaedic Research Unit, Department of Orthopaedic Surgery and Traumatology, Turku University Hospital, University of Turku, Turku FI-20521, Finland
| |
Collapse
|
18
|
Velikyan I. Prospective of ⁶⁸Ga-radiopharmaceutical development. Theranostics 2013; 4:47-80. [PMID: 24396515 PMCID: PMC3881227 DOI: 10.7150/thno.7447] [Citation(s) in RCA: 235] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 10/01/2013] [Indexed: 01/29/2023] Open
Abstract
Positron Emission Tomography (PET) experienced accelerated development and has become an established method for medical research and clinical routine diagnostics on patient individualized basis. Development and availability of new radiopharmaceuticals specific for particular diseases is one of the driving forces of the expansion of clinical PET. The future development of the ⁶⁸Ga-radiopharmaceuticals must be put in the context of several aspects such as role of PET in nuclear medicine, unmet medical needs, identification of new biomarkers, targets and corresponding ligands, production and availability of ⁶⁸Ga, automation of the radiopharmaceutical production, progress of positron emission tomography technologies and image analysis methodologies for improved quantitation accuracy, PET radiopharmaceutical regulations as well as advances in radiopharmaceutical chemistry. The review presents the prospects of the ⁶⁸Ga-based radiopharmaceutical development on the basis of the current status of these aspects as well as wide range and variety of imaging agents.
Collapse
Affiliation(s)
- Irina Velikyan
- 1. Preclinical PET Platform, Department of Medicinal Chemistry, Uppsala University, SE-75183 Uppsala, Sweden
- 2. PET-Centre, Centre for Medical Imaging, Uppsala University Hospital, SE-75185, Uppsala, Sweden
- 3. Department of Radiology, Oncology, and Radiation Science, Uppsala University, SE-75285 Uppsala, Sweden
| |
Collapse
|
19
|
Wu C, Li F, Niu G, Chen X. PET imaging of inflammation biomarkers. Theranostics 2013; 3:448-66. [PMID: 23843893 PMCID: PMC3706689 DOI: 10.7150/thno.6592] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 05/24/2013] [Indexed: 01/04/2023] Open
Abstract
Inflammation plays a significant role in many disease processes. Development in molecular imaging in recent years provides new insight into the diagnosis and treatment evaluation of various inflammatory diseases and diseases involving inflammatory process. Positron emission tomography using (18)F-FDG has been successfully applied in clinical oncology and neurology and in the inflammation realm. In addition to glucose metabolism, a variety of targets for inflammation imaging are being discovered and utilized, some of which are considered superior to FDG for imaging inflammation. This review summarizes the potential inflammation imaging targets and corresponding PET tracers, and the applications of PET in major inflammatory diseases and tumor associated inflammation. Also, the current attempt in differentiating inflammation from tumor using PET is also discussed.
Collapse
|
20
|
Vascular adhesion protein 1 in the eye. J Ophthalmol 2013; 2013:925267. [PMID: 23840939 PMCID: PMC3687510 DOI: 10.1155/2013/925267] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 04/17/2013] [Accepted: 05/14/2013] [Indexed: 11/29/2022] Open
Abstract
Semicarbazide-sensitive amine oxidase/vascular adhesion protein-1 (SSAO/VAP-1), a dual-function molecule with adhesive and enzymatic properties, is expressed on the surface of vascular endothelial cells of mammals. It also exists as a soluble form (sVAP-1), which is implicated in oxidative stress via its enzymatic activity and can be a prognostic biomarker. Recent evidence suggests that VAP-1 is an important therapeutic target for several inflammation-related ocular diseases, such as uveitis, age-related macular degeneration (AMD), and diabetic retinopathy (DR), by involving in the recruitment of leukocytes at sites of inflammation. Furthermore, VAP-1 plays an important role in the pathogenesis of conjunctival inflammatory diseases such as pyogenic granulomas and the progression of conjunctival lymphoma. VAP-1 may be an alternative therapeutic target in ocular diseases. The in vivo imaging of inflammation using VAP-1 as a target molecule is a novel approach with a potential for early detection and characterization of inflammatory diseases. This paper reviews the critical roles of VAP-1 in ophthalmological diseases which may provide a novel research direction or a potent therapeutic strategy.
Collapse
|
21
|
Autio A, Jalkanen S, Roivainen A. Nuclear imaging of inflammation: homing-associated molecules as targets. EJNMMI Res 2013; 3:1. [PMID: 23281702 PMCID: PMC3557172 DOI: 10.1186/2191-219x-3-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 12/18/2012] [Indexed: 02/07/2023] Open
Abstract
The golden standard in nuclear medicine imaging of inflammation is the use of autologous radiolabeled leukocytes. Although their diagnostic accuracy is precise, the preparation of the leukocytes is both laborious and potentially hazardous for laboratory personnel. Molecules involved in leukocyte migration (homing-associated molecules) could serve as targets for the development of imaging agents for inflammation. An excellent target would be a molecule that is absent or expressed at low levels in healthy tissues, but is present or upregulated at the sites of inflammation. In this paper, we will review the literature concerning the use of homing-associated molecules as imaging targets. We will especially concentrate on vascular adhesion protein-1 due to the promising results regarding its use as a target for the imaging of inflammation.
Collapse
Affiliation(s)
- Anu Autio
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, Turku, 20521, Finland.
| | | | | |
Collapse
|
22
|
Abstract
Development of new radiopharmaceuticals and their availability are crucial factors influencing the expansion of clinical nuclear medicine. The number of new (68)Ga-based imaging agents for positron emission tomography (PET) is increasing greatly. (68)Ga has been used for labeling of a broad range of molecules (small organic molecules, peptides, proteins, and oligonucleotides) as well as particles, thus demonstrating its potential to become a PET analog of the legendary generator-produced gamma-emitting (99m)Tc but with added value of higher sensitivity and resolution as well as quantitation and dynamic scanning. Further, the availability of technology for GMP-compliant automated tracer production can facilitate the introduction of new radiopharmaceuticals and enable standardized, harmonized multicenter studies to be conducted for regulatory approval. This chapter presents some examples of tracers for targeted, pretargeted, and nontargeted imaging with emphasis on the potential of (68)Ga to facilitate clinically practical PET development and to promote the PET technique worldwide for earlier and better diagnostics, and personalized medicine with the ultimate objective of improved therapeutic outcome.
Collapse
Affiliation(s)
- Irina Velikyan
- Department of Radiology, Uppsala University, Uppsala, Sweden.
| |
Collapse
|
23
|
Smith DL, Breeman WAP, Sims-Mourtada J. The untapped potential of Gallium 68-PET: the next wave of ⁶⁸Ga-agents. Appl Radiat Isot 2012; 76:14-23. [PMID: 23232184 DOI: 10.1016/j.apradiso.2012.10.014] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 10/16/2012] [Accepted: 10/17/2012] [Indexed: 12/20/2022]
Abstract
(68)Gallium-PET ((68)Ga-PET) agents have significant clinical promise. The radionuclide can be produced from a (68)Ge/(68)Ga generator on site and is a convenient alternative to cyclotron-based PET isotopes. The short half-life of (68)Ga permits imaging applications with sufficient radioactivity while maintaining patient dose to an acceptable level. Furthermore, due to superior resolution, (68)Ga-PET agents have the ability to replace current SPECT agents in many applications. This article outlines the upcoming agents and challenges faced during the translational development of (68)Ga agents.
Collapse
Affiliation(s)
- Daniel L Smith
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston TX, USA
| | | | | |
Collapse
|
24
|
Roivainen A, Jalkanen S, Nanni C. Gallium-labelled peptides for imaging of inflammation. Eur J Nucl Med Mol Imaging 2012; 39 Suppl 1:S68-77. [PMID: 22388620 DOI: 10.1007/s00259-011-1987-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Inflammation plays a major role in the development of many diseases. This review article summarizes recent research in the field of in vivo imaging of inflammation. Novel methodologies using PET with (68)Ga peptides targeting, for example, vascular adhesion protein 1 are discussed.
Collapse
Affiliation(s)
- Anne Roivainen
- Turku PET Centre, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, FI-20521 Turku, Finland.
| | | | | |
Collapse
|
25
|
Affiliation(s)
- S. Anna Sargsyan
- From the Department of Medicine, University of Colorado School of Medicine, Aurora, CO
| | - Joshua M. Thurman
- From the Department of Medicine, University of Colorado School of Medicine, Aurora, CO
| |
Collapse
|
26
|
Gemmel F, Van den Wyngaert H, Love C, Welling MM, Gemmel P, Palestro CJ. Prosthetic joint infections: radionuclide state-of-the-art imaging. Eur J Nucl Med Mol Imaging 2012; 39:892-909. [PMID: 22361912 DOI: 10.1007/s00259-012-2062-7] [Citation(s) in RCA: 139] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 01/02/2012] [Indexed: 12/27/2022]
Abstract
Prosthetic joint replacement surgery is performed with increasing frequency. Overall the incidence of prosthetic joint infection (PJI) and subsequently prosthesis revision failure is estimated to be between 1 and 3%. Differentiating infection from aseptic mechanical loosening, which is the most common cause of prosthetic failure, is especially important because of different types of therapeutic management. Despite a thorough patient history, physical examination, multiple diagnostic tests and complex algorithms, differentiating PJI from aseptic loosening remains challenging. Among imaging modalities, radiographs are neither sensitive nor specific and cross-sectional imaging techniques, such as computed tomography and magnetic resonance imaging, are limited by hardware-induced artefacts. Radionuclide imaging reflects functional rather than anatomical changes and is not hampered by the presence of a metallic joint prosthesis. As a result scintigraphy is currently the modality of choice in the investigation of suspected PJI. Unfortunately, there is no true consensus about the gold standard technique since there are several drawbacks and limitations inherent to each modality. Bone scintigraphy (BS) is sensitive for identifying the failed joint replacement, but cannot differentiate between infection and aseptic loosening. Combined bone/gallium scintigraphy (BS/GS) offers modest improvement over BS alone for diagnosing PJI. However, due to a number of drawbacks, BS/GS has generally been superseded by other techniques but it still may have a role in neutropenic patients. Radiolabelled leucocyte scintigraphy remains the gold standard technique for diagnosing neutrophil-mediated processes. It seems to be that combined in vitro labelled leucocyte/bone marrow scintigraphy (LS/BMS), with an accuracy of about 90%, is currently the imaging modality of choice for diagnosing PJI. There are, however, significant limitations using in vitro labelled leucocytes and considerable effort has been devoted to developing alternative radiotracers, such as radiolabelled HIGs, liposomes, antigranulocyte antibodies and fragments, as well as more investigational tracers such as radiolabelled antibiotics, antimicrobial peptides, bacteriophages and thymidine kinase. On the other hand, positron emission tomography (PET) is still growing in the field of PJI imaging with radiotracers such as (18)F-fluorodeoxyglucose (FDG), (18)F-FDG white blood cells and (18)F-fluoride. But unfortunately this superb tomographic technique will only receive full acceptance when specific PET uptake patterns can be successfully developed. The emergence of hybrid modality imaging using integrated single photon emission computed tomography (SPECT) and PET with computed tomography (SPECT/CT and PET/CT) may also have a contributing role for more accurate assessment of joint replacement complications, especially combined with new radiotracers such as (68)Ga and (64)Cu. Finally, in searching for infection-specific tracers, currently there is no such diagnostic agent available.
Collapse
Affiliation(s)
- Filip Gemmel
- Department of Nuclear Medicine, AZ Alma Campus Sijsele, Gentse Steenweg 132, 8340 Sijsele-Damme, Belgium.
| | | | | | | | | | | |
Collapse
|
27
|
Abstract
New aggressive pathogens are responsible for the increasing incidence and difficult management of infections. Modern epidemics such as diabetes are frequently complicated by severe infections with subsequent high morbidity. Diagnosis (essentially early detection of infection) and also management decision making pose clinical challenges. Many resources are invested in developing precise, noninvasive diagnostic tests and efficient therapies for infectious processes. Nuclear medicine procedures are part of the evaluation armamentarium of patients with suspected or confirmed infection. Their strength relies on the fact that they are noninvasive tests that provide both functional as well as metabolic information early in the course of disease. Their limitations relate to the need for specific radiotracers and the rather low resolution of images. These limitations have been largely overcome by the hybrid PET/CT and SPECT/CT technology. PET/CT, primarily using FDG, is redefining the diagnostic work up and is currently leading to changes in the management of patients with suspected or known infections. The main indications for FDG PET/CT in infection, as well as updated literature results, are presented in the following review.
Collapse
Affiliation(s)
- Ora Israel
- Department of Nuclear Medicine, Rambam Health Care Campus and Rappaport School of Medicine, Technion, Israel Institute of Technology, Haifa, Israel.
| | | |
Collapse
|
28
|
Siglec-9 is a novel leukocyte ligand for vascular adhesion protein-1 and can be used in PET imaging of inflammation and cancer. Blood 2011; 118:3725-33. [PMID: 21821708 DOI: 10.1182/blood-2010-09-311076] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Leukocyte migration to sites of inflammation is regulated by several endothelial adhesion molecules. Vascular adhesion protein-1 (VAP-1) is unique among the homing-associated molecules as it is both an enzyme that oxidizes primary amines and an adhesin. Although granulocytes can bind to endothelium via a VAP-1-dependent manner, the counter-receptor(s) on this leukocyte population is(are) not known. Here we used a phage display approach and identified Siglec-9 as a candidate ligand on granulocytes. The binding between Siglec-9 and VAP-1 was confirmed by in vitro and ex vivo adhesion assays. The interaction sites between VAP-1 and Siglec-9 were identified by molecular modeling and confirmed by further binding assays with mutated proteins. Although the binding takes place in the enzymatic groove of VAP-1, it is only partially dependent on the enzymatic activity of VAP-1. In positron emission tomography, the ⁶⁸Gallium-labeled peptide of Siglec-9 specifically detected VAP-1 in vasculature at sites of inflammation and cancer. Thus, the peptide binding to the enzymatic groove of VAP-1 can be used for imaging conditions, such as inflammation and cancer.
Collapse
|
29
|
Autio A, Henttinen T, Sipilä HJ, Jalkanen S, Roivainen A. Mini-PEG spacering of VAP-1-targeting 68Ga-DOTAVAP-P1 peptide improves PET imaging of inflammation. EJNMMI Res 2011; 1:10. [PMID: 22214508 PMCID: PMC3251254 DOI: 10.1186/2191-219x-1-10] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 07/26/2011] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Vascular adhesion protein-1 (VAP-1) is an adhesion molecule that plays a key role in recruiting leucocytes into sites of inflammation. We have previously shown that 68Gallium-labelled VAP-1-targeting peptide (68Ga-DOTAVAP-P1) is a positron emission tomography (PET) imaging agent, capable of visualising inflammation in rats, but disadvantaged by its short metabolic half-life and rapid clearance. We hypothesised that prolonging the metabolic half-life of 68Ga-DOTAVAP-P1 could further improve its imaging characteristics. In this study, we evaluated a new analogue of 68Ga-DOTAVAP-P1 modified with a mini-polyethylene glycol (PEG) spacer (68Ga-DOTAVAP-PEG-P1) for in vivo imaging of inflammation. METHODS Whole-body distribution kinetics and visualisation of inflammation in a rat model by the peptides 68Ga-DOTAVAP-P1 and 68Ga-DOTAVAP-PEG-P1 were evaluated in vivo by dynamic PET imaging and ex vivo by measuring the radioactivity of excised tissues. In addition, plasma samples were analysed by radio-HPLC for the in vivo stability of the peptides. RESULTS The peptide with the mini-PEG spacer showed slower renal excretion but similar liver uptake as the original peptide. At 60 min after injection, the standardised uptake value of the inflammation site was 0.33 ± 0.07 for 68Ga-DOTAVAP-P1 and 0.53 ± 0.01 for 68Ga-DOTAVAP-PEG-P1 by PET. In addition, inflammation-to-muscle ratios were 6.7 ± 1.3 and 7.3 ± 2.1 for 68Ga-DOTAVAP-P1 and 68Ga-DOTAVAP-PEG-P1, respectively. The proportion of unchanged peptide in circulation at 60 min after injection was significantly higher for 68Ga-DOTAVAP-PEG-P1 (76%) than for 68Ga-DOTAVAP-P1 (19%). CONCLUSION The eight-carbon mini-PEG spacer prolonged the metabolic half-life of the 68Ga-DOTAVAP-P1 peptide, leading to higher target-to-background ratios and improved in vivo PET imaging of inflammation.
Collapse
Affiliation(s)
- Anu Autio
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland.
| | | | | | | | | |
Collapse
|
30
|
Zeglis BM, Lewis JS. A practical guide to the construction of radiometallated bioconjugates for positron emission tomography. Dalton Trans 2011; 40:6168-95. [PMID: 21442098 PMCID: PMC3773488 DOI: 10.1039/c0dt01595d] [Citation(s) in RCA: 151] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Positron emission tomography (PET) has become a vital imaging modality in the diagnosis and treatment of disease, most notably cancer. A wide array of small molecule PET radiotracers have been developed that employ the short half-life radionuclides (11)C, (13)N, (15)O, and (18)F. However, PET radiopharmaceuticals based on biomolecular targeting vectors have been the subject of dramatically increased research in both the laboratory and the clinic. Typically based on antibodies, oligopeptides, or oligonucleotides, these tracers have longer biological half-lives than their small molecule counterparts and thus require labeling with radionuclides with longer, complementary radioactive half-lives, such as the metallic isotopes (64)Cu, (68)Ga, (86)Y, and (89)Zr. Each bioconjugate radiopharmaceutical has four component parts: biomolecular vector, radiometal, chelator, and covalent link between chelator and biomolecule. With the exception of the radiometal, a tremendous variety of choices exists for each of these pieces, and a plethora of different chelation, conjugation, and radiometallation strategies have been utilized to create agents ranging from (68)Ga-labeled pentapeptides to (89)Zr-labeled monoclonal antibodies. Herein, the authors present a practical guide to the construction of radiometal-based PET bioconjugates, in which the design choices and synthetic details of a wide range of biomolecular tracers from the literature are collected in a single reference. In assembling this information, the authors hope both to illuminate the diverse methods employed in the synthesis of these agents and also to create a useful reference for molecular imaging researchers both experienced and new to the field.
Collapse
Affiliation(s)
- Brian M. Zeglis
- Department of Radiology and Program in Molecular Pharmacology and Chemistry Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA. Fax: (646)-888-3039; Tel: (646)-888-3038
| | - Jason S. Lewis
- Department of Radiology and Program in Molecular Pharmacology and Chemistry Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA. Fax: (646)-888-3039; Tel: (646)-888-3038
| |
Collapse
|
31
|
Dunkel P, Balogh B, Meleddu R, Maccioni E, Gyires K, Mátyus P. Semicarbazide-sensitive amine oxidase/vascular adhesion protein-1: a patent survey. Expert Opin Ther Pat 2011; 21:1453-71. [PMID: 21675926 DOI: 10.1517/13543776.2011.594040] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Vascular adhesion protein-1 (VAP-1)/semicarbazide-sensitive amine oxidase (SSAO) is an adhesion protein involved in leukocyte trafficking and inflammatory processes, with a special amine oxidase activity. Inhibitors have been mainly developed for treating chronic inflammatory disorders. The utility of inhibitors as antiangiogenic agents in ophthalmological and oncological diseases is currently under evaluation. SSAO substrates may mimic several insulin effects, although their utility for the treatment of diabetes is still far from being fully understood. AREAS COVERED This paper reviews the patent literature of SSAO/VAP-1 inhibitors and substrates, for the period of 1990 - 2010. The current stage of SSAO/VAP-1-interacting agents published in patents is described, along with their chemical structures and pharmacological uses. EXPERT OPINION SSAO/VAP-1 is a promising anti-inflammatory target. Another important field for therapeutic application of these inhibitors may be ophthalmology, due to their antiangiogenic effects. SSAO substrates might also be of therapeutic value in the treatment of diabetes; however, more extensive research has to be undertaken to validate this approach.
Collapse
Affiliation(s)
- Petra Dunkel
- Semmelweis University, Department of Organic Chemistry , Hőgyes Endre utca 7, 1092 Budapest , Hungary
| | | | | | | | | | | |
Collapse
|
32
|
The use of selective volatization in the separation of 68Ge from irradiated Ga targets. Appl Radiat Isot 2011; 69:727-31. [DOI: 10.1016/j.apradiso.2011.01.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Revised: 12/15/2010] [Accepted: 01/20/2011] [Indexed: 11/13/2022]
|
33
|
Li Z, Conti PS. Radiopharmaceutical chemistry for positron emission tomography. Adv Drug Deliv Rev 2010; 62:1031-51. [PMID: 20854860 DOI: 10.1016/j.addr.2010.09.007] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 09/11/2010] [Accepted: 09/13/2010] [Indexed: 12/13/2022]
Abstract
Molecular imaging is an emerging technology that allows the visualization of interactions between molecular probes and biological targets. Molecules that either direct or are subject to homeostatic controls in biological systems could be labeled with the appropriate radioisotopes for the quantitative measurement of selected molecular interactions during normal tissue homeostasis and again after perturbations of the normal state. In particular, positron emission tomography (PET) offers picomolar sensitivity and is a fully translational technique that requires specific probes radiolabeled with a usually short-lived positron-emitting radionuclide. PET has provided the capability of measuring biological processes at the molecular and metabolic levels in vivo by the detection of the gamma rays formed as a result of the annihilation of the positrons emitted. Despite the great wealth of information that such probes can provide, the potential of PET strongly depends on the availability of suitable PET radiotracers. However, the development of new imaging probes for PET is far from trivial and radiochemistry is a major limiting factor for the field of PET. In this review, we provided an overview of the most common chemical approaches for the synthesis of PET-labeled molecules and highlighted the most recent developments and trends. The discussed PET radionuclides include ¹¹C (t₁(/)₂=20.4min), ¹³N (t₁(/)₂=9.9min), ¹⁵O (t₁(/)₂=2min), ⁶⁸Ga (t₁(/)₂=68min), ¹⁸F (t₁(/)₂=109.8min), ⁶⁴Cu (t₁(/)₂=12.7h), and ¹²⁴I (t₁(/)₂=4.12d).
Collapse
|
34
|
Autio A, Ujula T, Luoto P, Salomäki S, Jalkanen S, Roivainen A. PET imaging of inflammation and adenocarcinoma xenografts using vascular adhesion protein 1 targeting peptide 68Ga-DOTAVAP-P1: comparison with 18F-FDG. Eur J Nucl Med Mol Imaging 2010; 37:1918-25. [PMID: 20523988 DOI: 10.1007/s00259-010-1497-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Accepted: 05/01/2010] [Indexed: 12/13/2022]
Abstract
PURPOSE The aim of this study was to evaluate inflammation and tumour imaging with a vascular adhesion protein 1 (VAP-1) targeting peptide (68)Ga-DOTAVAP-P1 in comparison with (18)F-FDG. METHODS Rats with both subcutaneous human pancreatic adenocarcinoma xenografts and turpentine oil-induced acute sterile inflammation were evaluated by dynamic positron emission tomography (PET) and by digital autoradiography of tissue cryosections. Subsequently, the autoradiographs were combined with histological and immunohistological analysis of the sections. RESULTS (68)Ga-DOTAVAP-P1 delineated acute, sterile inflammation comparable with (18)F-FDG. However, the tumour uptake of (68)Ga-DOTAVAP-P1 was low in contrast to prominent (18)F-FDG uptake. The standardised uptake values of inflammation and tumours by PET were 1.1 +/- 0.4 (mean +/- SEM) and 0.4 +/- 0.1 for (68)Ga-DOTAVAP-P1 and 2.0 +/- 0.5 and 1.6 +/- 0.8 for (18)F-FDG, respectively. In addition, PET studies showed inflammation to muscle and tumour to muscle ratios of 5.1 +/- 3.1 and 1.7 +/- 0.3 for (68)Ga-DOTAVAP-P1 and 6.2 +/- 0.7 and 4.6 +/- 2.2 for (18)F-FDG, respectively. Immunohistochemistry revealed increased expression of luminal VAP-1 on the endothelium at the site of inflammation and low expression in the tumour CONCLUSION The (68)Ga-DOTAVAP-P1 PET was able to visualise inflammation better than tumour, which was in accordance with the luminal expression of VAP-1 on vasculature in these experimental models.
Collapse
Affiliation(s)
- Anu Autio
- Turku PET Centre, University of Turku and Turku University Hospital, 20521 Turku, Finland
| | | | | | | | | | | |
Collapse
|
35
|
Computer controlled 68Ga milking and concentration system. Appl Radiat Isot 2010; 68:1057-9. [DOI: 10.1016/j.apradiso.2010.01.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 01/05/2010] [Accepted: 01/10/2010] [Indexed: 12/14/2022]
|
36
|
Silvola J, Autio A, Luoto P, Jalkanen S, Roivainen A. Preliminary evaluation of novel68Ga-DOTAVAP-PEG-P2 peptide targeting vascular adhesion protein-1. Clin Physiol Funct Imaging 2010; 30:75-8. [DOI: 10.1111/j.1475-097x.2009.00907.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|