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Metelerkamp Cappenberg T, De Schepper S, Vangestel C, De Lombaerde S, Wyffels L, Van den Wyngaert T, Mattis J, Gray B, Pak K, Stroobants S, Elvas F. First-in-human study of a novel cell death tracer [ 99mTc]Tc-Duramycin: safety, biodistribution and radiation dosimetry in healthy volunteers. EJNMMI Radiopharm Chem 2023; 8:20. [PMID: 37646865 PMCID: PMC10468453 DOI: 10.1186/s41181-023-00207-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 08/23/2023] [Indexed: 09/01/2023] Open
Abstract
BACKGROUND Imaging of cell death can provide an early indication of treatment response in cancer. [99mTc]Tc-Duramycin is a small-peptide SPECT tracer that recognizes both apoptotic and necrotic cells by binding to phosphatidylethanolamine present in the cell membrane. Preclinically, this tracer has shown to have favorable pharmacokinetics and selective tumor accumulation early after the onset of anticancer therapy. In this first-in-human study, we report the safety, biodistribution and internal radiation dosimetry of [99mTc]Tc-Duramycin in healthy human volunteers. RESULTS Six healthy volunteers (3 males, 3 females) were injected intravenously with [99mTc]Tc-Duramycin (dose: 6 MBq/kg; 473 ± 36 MBq). [99mTc]Tc-Duramycin was well tolerated in all subjects, with no serious adverse events reported. Following injection, a 30-min dynamic planar imaging of the abdomen was performed, and whole-body (WB) planar scans were acquired at 1, 2, 3, 6 and 23 h post-injection (PI), with SPECT acquisitions after each WB scan and one low-dose CT after the first SPECT. In vivo 99mTc activities were determined from semi-quantitative analysis of the images, and time-activity curves were generated. Residence times were calculated from the dynamic and WB planar scans. The mean effective dose was 7.61 ± 0.75 µSv/MBq, with the kidneys receiving the highest absorbed dose (planar analysis: 43.82 ± 4.07 µGy/MBq, SPECT analysis: 19.72 ± 3.42 μGy/MBq), followed by liver and spleen. The median effective dose was 3.61 mSv (range, 2.85-4.14). The tracer cleared slowly from the blood (effective half-life of 2.0 ± 0.4 h) due to high plasma protein binding with < 5% free tracer 3 h PI. Excretion was almost exclusively renal. CONCLUSION [99mTc]Tc-Duramycin demonstrated acceptable dosimetry (< 5 mSv) and a favorable safety profile. Due to slow blood clearance, optimal target-to-background ratios are expected 5 h PI. These data support the further assessment of [99mTc]Tc-Duramycin for clinical treatment response evaluation. TRIAL REGISTRATION NCT05177640, Registered April 30, 2021, https://clinicaltrials.gov/study/NCT05177640 .
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Affiliation(s)
| | - Stijn De Schepper
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), Edegem, Belgium
| | - Christel Vangestel
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), Edegem, Belgium
- Molecular Imaging and Radiology (MIRA), University of Antwerp, Wilrijk, Belgium
| | - Stef De Lombaerde
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), Edegem, Belgium
- Molecular Imaging and Radiology (MIRA), University of Antwerp, Wilrijk, Belgium
| | - Leonie Wyffels
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), Edegem, Belgium
- Molecular Imaging and Radiology (MIRA), University of Antwerp, Wilrijk, Belgium
| | - Tim Van den Wyngaert
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), Edegem, Belgium
- Molecular Imaging and Radiology (MIRA), University of Antwerp, Wilrijk, Belgium
| | - Jeffrey Mattis
- Molecular Targeting Technologies, Inc., West Chester, PA, USA
| | - Brian Gray
- Molecular Targeting Technologies, Inc., West Chester, PA, USA
| | - Koon Pak
- Molecular Targeting Technologies, Inc., West Chester, PA, USA
| | - Sigrid Stroobants
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), Edegem, Belgium
- Molecular Imaging and Radiology (MIRA), University of Antwerp, Wilrijk, Belgium
| | - Filipe Elvas
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), Edegem, Belgium.
- Molecular Imaging and Radiology (MIRA), University of Antwerp, Wilrijk, Belgium.
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Bertoglio D, Zajicek F, Lombaerde SD, Miranda A, Stroobants S, Wang Y, Dominguez C, Munoz-Sanjuan I, Bard J, Liu L, Verhaeghe J, Staelens S. Validation, kinetic modeling, and test-retest reproducibility of [ 18F]SynVesT-1 for PET imaging of synaptic vesicle glycoprotein 2A in mice. J Cereb Blood Flow Metab 2022; 42:1867-1878. [PMID: 35570828 PMCID: PMC9536120 DOI: 10.1177/0271678x221101648] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Alterations in synaptic vesicle glycoprotein 2 A (SV2A) have been associated with several neuropsychiatric and neurodegenerative disorders. Therefore, SV2A positron emission tomography (PET) imaging may provide a unique tool to investigate synaptic density dynamics during disease progression and after therapeutic intervention. This study aims to extensively characterize the novel radioligand [18F]SynVesT-1 for preclinical applications. In C57Bl/6J mice (n = 39), we assessed the plasma profile of [18F]SynVesT-1, validated the use of a noninvasive image-derived input function (IDIF) compared to an arterial input function (AIF), performed a blocking study with levetiracetam (50 and 200 mg/kg, i.p.) to verify the specificity towards SV2A, examined kinetic models for volume of distribution (VT) quantification, and explored test-retest reproducibility of [18F]SynVesT-1 in the central nervous system (CNS). Plasma availability of [18F]SynVesT-1 decreased rapidly (13.4 ± 1.5% at 30 min post-injection). VT based on AIF and IDIF showed excellent agreement (r2 = 0.95, p < 0.0001) and could be reliably estimated with a 60-min acquisition. The blocking study resulted in a complete blockade with no suitable reference region. Test-retest analysis indicated good reproducibility (mean absolute variability <10%). In conclusion, [18F]SynVesT-1 is selective for SV2A with optimal kinetics representing a candidate tool to quantify CNS synaptic density non-invasively.
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Affiliation(s)
- Daniele Bertoglio
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Antwerp, Belgium
| | - Franziska Zajicek
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Antwerp, Belgium
| | - Stef De Lombaerde
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Antwerp, Belgium.,Department of Nuclear Medicine, Antwerp University Hospital, Edegem, Belgium
| | - Alan Miranda
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Antwerp, Belgium
| | - Sigrid Stroobants
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Antwerp, Belgium.,Department of Nuclear Medicine, Antwerp University Hospital, Edegem, Belgium
| | - Yuchuan Wang
- CHDI Management/CHDI Foundation, Los Angeles, California, USA
| | - Celia Dominguez
- CHDI Management/CHDI Foundation, Los Angeles, California, USA
| | | | - Jonathan Bard
- CHDI Management/CHDI Foundation, Los Angeles, California, USA
| | - Longbin Liu
- CHDI Management/CHDI Foundation, Los Angeles, California, USA
| | - Jeroen Verhaeghe
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Antwerp, Belgium
| | - Steven Staelens
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Antwerp, Belgium
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Bertoglio D, Halloin N, Lombaerde SD, Jankovski A, Verhaeghe J, Nicaise C, Staelens S. SV2A PET Imaging Is a Noninvasive Marker for the Detection of Spinal Damage in Experimental Models of Spinal Cord Injury. J Nucl Med 2022; 63:1245-1251. [PMID: 35027368 PMCID: PMC9364338 DOI: 10.2967/jnumed.121.263222] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 11/30/2021] [Indexed: 02/03/2023] Open
Abstract
Traumatic spinal cord injury (SCI) is a neurologic condition characterized by long-term motor and sensory neurologic deficits as a consequence of an external physical impact damaging the spinal cord. Anatomic MRI is considered the gold-standard diagnostic tool to obtain structural information for the prognosis of acute SCI; however, it lacks functional objective information to assess SCI progression and recovery. In this study, we explored the use of synaptic vesicle glycoprotein 2A (SV2A) PET imaging to detect spinal cord lesions noninvasively after SCI. Methods: Mice (n = 7) and rats (n = 8) subjected to unilateral moderate cervical (C5) contusion were euthanized 1 wk after SCI for histologic and autoradiographic (3H-labeled (4R)-1-[(3-methylpyridin-4-yl)methyl]-4-(3,4,5-trifluorophenyl)pyrrolidin-2-one [UCB-J]) investigation of SV2A levels. Longitudinal 11C-UCB-J PET/CT imaging was performed in sham (n = 7) and SCI rats (n = 8) 1 wk and 6 wk after SCI. Animals also underwent an 18F-FDG PET scan during the latter time point. Postmortem tissue SV2A analysis to corroborate in vivo PET findings was performed 6 wk after SCI. Results: A significant SV2A loss (ranging from -70.3% to -87.3%; P < 0.0001) was measured at the epicenter of the impact in vitro in both mouse and rat contusion SCI models. Longitudinal 11C-UCB-J PET imaging detected SV2A loss in SCI rats (-49.0% ± 8.1% at 1 wk and -52.0% ± 12.9% at 6 wk after SCI), with no change observed in sham rats. In contrast, 18F-FDG PET imaging measured only subtle hypometabolism (-17.6% ± 14.7%). Finally, postmortem 3H-UCB-J autoradiography correlated with the in vivo SV2A PET findings (r = 0.92, P < 0.0001). Conclusion:11C-UCB-J PET/CT imaging is a noninvasive marker for SV2A loss after SCI. Collectively, these findings indicate that SV2A PET may provide an objective measure of SCI and thus represent a valuable tool to evaluate novel therapeutics. Clinical assessment of SCI with SV2A PET imaging is highly recommended.
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Affiliation(s)
- Daniele Bertoglio
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium
| | | | - Stef De Lombaerde
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium;,Department of Nuclear Medicine, Antwerp University Hospital, Antwerp, Belgium
| | - Aleksandar Jankovski
- Institute of NeuroScience, NEUR Division, Université Catholique de Louvain, Louvain, Belgium; and,Department of Neurosurgery, CHU UCL Namur, Yvoir, Belgium
| | - Jeroen Verhaeghe
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium
| | | | - Steven Staelens
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium
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Glorie D, Verhaeghe J, Miranda A, De Lombaerde S, Stroobants S, Staelens S. Quantification of Metabotropic Glutamate Receptor 5 Availability With Both [ 11C]ABP688 and [ 18F]FPEB Positron Emission Tomography in the Sapap3 Knockout Mouse Model for Obsessive-Compulsive-like Behavior. Biol Psychiatry Cogn Neurosci Neuroimaging 2022; 7:607-615. [PMID: 34856382 DOI: 10.1016/j.bpsc.2021.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 11/17/2021] [Accepted: 11/20/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND This study provides a first direct comparison between positron emission tomography radioligands targeting the allosteric site of the metabotropic glutamate receptor 5 (mGluR5): [11C]ABP688 and [18F]FPEB. A blocking paradigm was set up to substantiate the common binding site of both radioligands. Second, both radioligands were applied in Sapap3 knockout (KO) mice showing compulsive-like behavior characterized by a lower in vivo mGluR5 availability. METHODS First, wild-type mice (n = 7) received four position emission tomography/computed tomography scans: a [11C]ABP688 scan, a [18F]FPEB scan, and two blocking scans using cold FPEB and cold ABP688, respectively. A second experiment compared both radioligands in wild-type (n = 7) and KO (n = 10) mice. The simplified reference tissue model was used to calculate the nondisplaceable binding potential representing the in vivo availability of mGluR5 in the brain. RESULTS Using cold FPEB as a blocking compound for [11C]ABP688 micro-positron emission tomography and vice versa, we observed averaged global reductions in mGluR5 availability of circa 98% for [11C]ABP688 and 82%-96% for [18F]FPEB. For KOs, the [11C]ABP688 nondisplaceable binding potential was on average 25% lower compared with wild-type control mice (p < .0001-.001), while this was about 17% for [18F]FPEB (p < .05). CONCLUSIONS The current findings substantiate a common binding site and suggest a strong relationship between mGluR5 availability levels measured with both radioligands. In Sapap3 KO mice, a reduced mGluR5 availability could therefore be demonstrated with both radioligands. With [11C]ABP688, higher significance levels were achieved in more brain regions. These findings suggest [11C]ABP688 as a preferable radiotracer to quantify mGluR5 availability, as exemplified here in a model for compulsive-like behavior.
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Affiliation(s)
- Dorien Glorie
- Molecular Imaging Center Antwerp, University of Antwerp, Wilrijk, Belgium
| | - Jeroen Verhaeghe
- Molecular Imaging Center Antwerp, University of Antwerp, Wilrijk, Belgium
| | - Alan Miranda
- Molecular Imaging Center Antwerp, University of Antwerp, Wilrijk, Belgium
| | - Stef De Lombaerde
- Molecular Imaging Center Antwerp, University of Antwerp, Wilrijk, Belgium; Department of Nuclear Medicine, Antwerp University Hospital, Edegem, Belgium
| | - Sigrid Stroobants
- Molecular Imaging Center Antwerp, University of Antwerp, Wilrijk, Belgium; Department of Nuclear Medicine, Antwerp University Hospital, Edegem, Belgium
| | - Steven Staelens
- Molecular Imaging Center Antwerp, University of Antwerp, Wilrijk, Belgium.
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Bertoglio D, Bard J, Hessmann M, Liu L, Gärtner A, De Lombaerde S, Huscher B, Zajicek F, Miranda A, Peters F, Herrmann F, Schaertl S, Vasilkovska T, Brown CJ, Johnson PD, Prime ME, Mills MR, Van der Linden A, Mrzljak L, Khetarpal V, Wang Y, Marchionini DM, Skinbjerg M, Verhaeghe J, Dominguez C, Staelens S, Munoz-Sanjuan I. Development of a ligand for in vivo imaging of mutant huntingtin in Huntington's disease. Sci Transl Med 2022; 14:eabm3682. [PMID: 35108063 DOI: 10.1126/scitranslmed.abm3682] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Huntington's disease (HD) is a dominantly inherited neurodegenerative disorder caused by a CAG trinucleotide expansion in the huntingtin (HTT) gene that encodes the pathologic mutant HTT (mHTT) protein with an expanded polyglutamine (polyQ) tract. Whereas several therapeutic programs targeting mHTT expression have advanced to clinical evaluation, methods to visualize mHTT protein species in the living brain are lacking. Here, we demonstrate the development and characterization of a positron emission tomography (PET) imaging radioligand with high affinity and selectivity for mHTT aggregates. This small molecule radiolabeled with 11C ([11C]CHDI-180R) allowed noninvasive monitoring of mHTT pathology in the brain and could track region- and time-dependent suppression of mHTT in response to therapeutic interventions targeting mHTT expression in a rodent model. We further showed that in these animals, therapeutic agents that lowered mHTT in the striatum had a functional restorative effect that could be measured by preservation of striatal imaging markers, enabling a translational path to assess the functional effect of mHTT lowering.
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Affiliation(s)
- Daniele Bertoglio
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk 2610, Belgium
| | - Jonathan Bard
- CHDI Management/CHDI Foundation, Los Angeles, CA 90045, USA
| | | | - Longbin Liu
- CHDI Management/CHDI Foundation, Los Angeles, CA 90045, USA
| | | | - Stef De Lombaerde
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk 2610, Belgium.,Department of Nuclear Medicine, Antwerp University Hospital, Edegem 2650, Belgium
| | | | - Franziska Zajicek
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk 2610, Belgium
| | - Alan Miranda
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk 2610, Belgium
| | | | | | | | | | | | | | | | | | | | | | | | - Yuchuan Wang
- CHDI Management/CHDI Foundation, Los Angeles, CA 90045, USA
| | | | | | - Jeroen Verhaeghe
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk 2610, Belgium
| | | | - Steven Staelens
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk 2610, Belgium
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Elvas F, Tanc M, Van Rymenant Y, Beroske L, De Lombaerde S, Augustyns K, Staelens S, Stroobants S, De Meester I, Van der Veken P. Fluorinated PET imaging probes targeting fibroblast activation protein: radiolabeling and preclinical evaluation. Nucl Med Biol 2021. [DOI: 10.1016/s0969-8051(21)00329-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Glorie D, Verhaeghe J, Miranda A, De Lombaerde S, Stroobants S, Staelens S. Sapap3 deletion causes dynamic synaptic density abnormalities: a longitudinal [ 11C]UCB-J PET study in a model of obsessive-compulsive disorder-like behaviour. EJNMMI Res 2020; 10:140. [PMID: 33185747 PMCID: PMC7666267 DOI: 10.1186/s13550-020-00721-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 10/20/2020] [Indexed: 12/21/2022] Open
Abstract
Background Currently, the evidence on synaptic abnormalities in neuropsychiatric disorders—including obsessive–compulsive disorder (OCD)—is emerging. The newly established positron emission tomography (PET) ligand ((R)-1-((3-((11)C-methyl-(11)C)pyridin-4-yl)methyl)-4-(3,4,5-trifluorophenyl)pyrrolidin-2-one) ([11C]UCB-J) provides the opportunity to visualize synaptic density changes in vivo, by targeting the synaptic vesicle protein 2A (SV2A). Here, we aim to evaluate such alterations in the brain of the SAP90/PSD-95-associated protein 3 (Sapap3) knockout (ko) mouse model, showing an abnormal corticostriatal neurotransmission resulting in OCD-like behaviour. Methods Longitudinal [11C]UCB-J µPET/CT scans were acquired in Sapap3 ko and wildtype (wt) control mice (n = 9/group) to study SV2A availability. Based on the Logan reference method, we calculated the volume of distribution (VT(IDIF)) for [11C]UCB-J. Both cross-sectional (wt vs. ko) and longitudinal (3 vs. 9 months) volume-of-interest-based statistical analysis and voxel-based statistical parametric mapping were performed. Both [11C]UCB-J ex vivo autoradiography and [3H]UCB-J in vitro autoradiography were used for the validation of the µPET data. Results At the age of 3 months, Sapap3 ko mice are already characterized by a significantly lower SV2A availability compared to wt littermates (i.a. cortex − 12.69%, p < 0.01; striatum − 14.12%, p < 0.001, thalamus − 13.11%, p < 0.001, and hippocampus − 12.99%, p < 0.001). Healthy ageing in control mice was associated with a diffuse and significant (p < 0.001) decline throughout the brain, whereas in Sapap3 ko mice this decline was more confined to the corticostriatal level. A strong linear relationship (p < 0.0001) was established between the outcome parameters of [11C]UCB-J µPET and [11C]UCB-J ex vivo autoradiography, while such relationship was absent for [3H]UCB-J in vitro autoradiography. Conclusions [11C]UCB-J PET is a potential marker for synaptic density deficits in the Sapap3 ko mouse model for OCD, parallel to disease progression. Our data suggest that [11C]UCB-J ex vivo autoradiography is a suitable proxy for [11C]UCB-J PET data in mice.
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Affiliation(s)
- Dorien Glorie
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Universiteitsplein 1, Wilrijk, Belgium
| | - Jeroen Verhaeghe
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Universiteitsplein 1, Wilrijk, Belgium
| | - Alan Miranda
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Universiteitsplein 1, Wilrijk, Belgium
| | - Stef De Lombaerde
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Universiteitsplein 1, Wilrijk, Belgium.,Department of Nuclear Medicine, Antwerp University Hospital, Edegem, Belgium
| | - Sigrid Stroobants
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Universiteitsplein 1, Wilrijk, Belgium.,Department of Nuclear Medicine, Antwerp University Hospital, Edegem, Belgium
| | - Steven Staelens
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Universiteitsplein 1, Wilrijk, Belgium.
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Moon ES, Elvas F, Vliegen G, De Lombaerde S, Vangestel C, De Bruycker S, Bracke A, Eppard E, Greifenstein L, Klasen B, Kramer V, Staelens S, De Meester I, Van der Veken P, Rösch F. Targeting fibroblast activation protein (FAP): next generation PET radiotracers using squaramide coupled bifunctional DOTA and DATA 5m chelators. EJNMMI Radiopharm Chem 2020; 5:19. [PMID: 32728930 PMCID: PMC7391456 DOI: 10.1186/s41181-020-00102-z] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 07/15/2020] [Indexed: 12/19/2022] Open
Abstract
Background Fibroblast activation protein (FAP) is a proline selective serine protease that is overexpressed in tumor stroma and in lesions of many other diseases that are characterized by tissue remodeling. In 2014, a most potent FAP-inhibitor (referred to as UAMC1110) with low nanomolar FAP-affinity and high selectivity toward related enzymes such as prolyl oligopeptidase (PREP) and the dipeptidyl-peptidases (DPPs): DPP4, DPP8/9 and DPP2 were developed. This inhibitor has been adopted recently by other groups to create radiopharmaceuticals by coupling bifunctional chelator-linker systems. Here, we report squaric acid (SA) containing bifunctional DATA5m and DOTA chelators based on UAMC1110 as pharmacophor. The novel radiopharmaceuticals DOTA.SA.FAPi and DATA5m.SA.FAPi with their non-radioactive derivatives were characterized for in vitro inhibitory efficiency to FAP and PREP, respectively and radiochemical investigated with gallium-68. Further, first proof-of-concept in vivo animal study followed by ex vivo biodistribution were determined with [68Ga]Ga-DOTA.SA.FAPi. Results [68Ga]Ga-DOTA.SA.FAPi and [68Ga]Ga-DATA5m.SA.FAPi showed high complexation > 97% radiochemical yields after already 10 min and high stability over a period of 2 h. Affinity to FAP of DOTA.SA.FAPi and DATA5m.SA.FAPi and its natGa and natLu-labeled derivatives were excellent resulting in low nanomolar IC50 values of 0.7–1.4 nM. Additionally, all five compounds showed low affinity for the related protease PREP (high IC50 with 1.7–8.7 μM). First proof-of-principle in vivo PET-imaging animal studies of the [68Ga]Ga-DOTA.SA.FAPi precursor in a HT-29 human colorectal cancer xenograft mouse model indicated promising results with high accumulation in tumor (SUVmean of 0.75) and low background signal. Ex vivo biodistribution showed highest uptake in tumor (5.2%ID/g) at 60 min post injection with overall low uptake in healthy tissues. Conclusion In this work, novel PET radiotracers targeting fibroblast activation protein were synthesized and biochemically investigated. Critical substructures of the novel compounds are a squaramide linker unit derived from the basic motif of squaric acid, DOTA and DATA5m bifunctional chelators and a FAP-targeting moiety. In conclusion, these new FAP-ligands appear promising, both for further research and development as well as for first human application.
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Affiliation(s)
- Euy Sung Moon
- Department of Chemistry - TRIGA Site, Johannes Gutenberg University Mainz, 55128, Mainz, Germany
| | - Filipe Elvas
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), 2650, Edegem, Belgium
| | - Gwendolyn Vliegen
- Department of Pharmaceutical Sciences, Laboratory of Medical Biochemistry, University of Antwerp, 2610, Wilrijk, Belgium
| | - Stef De Lombaerde
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), 2650, Edegem, Belgium
| | - Christel Vangestel
- Department of Nuclear Medicine, Antwerp University Hospital (UZA), 2650, Edegem, Belgium
| | - Sven De Bruycker
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, 2610, Wilrijk, Belgium
| | - An Bracke
- Department of Pharmaceutical Sciences, Laboratory of Medical Biochemistry, University of Antwerp, 2610, Wilrijk, Belgium
| | | | - Lukas Greifenstein
- Department of Chemistry - TRIGA Site, Johannes Gutenberg University Mainz, 55128, Mainz, Germany
| | - Benedikt Klasen
- Department of Chemistry - TRIGA Site, Johannes Gutenberg University Mainz, 55128, Mainz, Germany
| | - Vasko Kramer
- Positronpharma SA, 7500921 Providencia, Santiago, Chile
| | - Steven Staelens
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, 2610, Wilrijk, Belgium
| | - Ingrid De Meester
- Department of Pharmaceutical Sciences, Laboratory of Medical Biochemistry, University of Antwerp, 2610, Wilrijk, Belgium
| | - Pieter Van der Veken
- Department of Pharmaceutical Sciences, Laboratory of Medical Biochemistry, University of Antwerp, 2610, Wilrijk, Belgium
| | - Frank Rösch
- Department of Chemistry - TRIGA Site, Johannes Gutenberg University Mainz, 55128, Mainz, Germany.
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Baguet T, Verhoeven J, Pauwelyn G, Hu J, Lambe P, De Lombaerde S, Piron S, Donche S, Descamps B, Goethals I, Vanhove C, De Vos F, Beyzavi MH. Radiosynthesis, in vitro and preliminary in vivo evaluation of the novel glutamine derived PET tracers [ 18F]fluorophenylglutamine and [ 18F]fluorobiphenylglutamine. Nucl Med Biol 2020; 86-87:20-29. [PMID: 32447069 DOI: 10.1016/j.nucmedbio.2020.03.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 03/13/2020] [Accepted: 03/31/2020] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Glucose has been deemed the driving force of tumor growth for decades. However, research has shown that several tumors metabolically shift towards glutaminolysis. The development of radiolabeled glutamine derivatives could be a useful molecular imaging tool for visualizing these tumors. We elaborated on the glutamine-derived PET tracers by developing two novel probes, namely [18F]fluorophenylglutamine and [18F]fluorobiphenylglutamine. MATERIALS AND METHODS Both tracers were labelled with fluorine-18 using our recently reported ruthenium-based direct aromatic fluorination method. Their affinity was evaluated with a [3H]glutamine inhibition experiment in a human PC-3 and a rat F98 cell line. The imaging potential of [18F]fluorophenylglutamine and [18F]fluorobiphenylglutamine was tested using a mouse PC-3 and a rat F98 tumor model. RESULTS The radiosynthesis of both tracers was successful with overall non-decay corrected yields of 18.46 ± 4.18% (n = 10) ([18F]fluorophenylglutamine) and 8.05 ± 3.25% (n = 5) ([18F]fluorobiphenylglutamine). In vitro inhibition experiments showed a moderate and low affinity of fluorophenylglutamine and fluorobiphenylglutamine, respectively, towards the human ASCT-2 transporter. Both compounds had a low affinity towards the rat ASCT-2 transporter. These results were endorsed by the in vivo experiments with low uptake of both tracers in the F98 rat xenograft, low uptake of [18F]FBPG in the mice PC-3 xenograft and a moderate uptake of [18F]FPG in the PC-3 tumors. CONCLUSION We investigated the imaging potential of two novel PET radiotracers [18F]FPG and [18F]FBPG. [18F]FPG is the first example of a glutamine radiotracer derivatized with a phenyl group which enables the exploration of further derivatization of the phenyl group to increase the affinity and imaging qualities. We hypothesize that increasing the affinity of [18F]FPG by optimizing the substituents of the arene ring can result in a high-quality glutamine-based PET radiotracer. Advances in Knowledge and Implications for patient care: We hereby report novel glutamine-based PET-tracers. These tracers are tagged on the arene group with fluorine-18, hereby preventing in vivo defluorination, which can occur with alkyl labelled tracers (e.g. (2S,4R)4-[18F]fluoroglutamine). [18F]FPG shows clear tumor uptake in vivo, has no in vivo defluorination and has a straightforward production. We believe this tracer is a good starting point for the development of a high-quality tracer which is useful for the clinical visualization of the glutamine transport.
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Affiliation(s)
- Tristan Baguet
- Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium.
| | | | - Glenn Pauwelyn
- Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
| | - Jiyun Hu
- Department of Chemistry and Biochemistry, University of Arkansas, AR, USA
| | - Patricia Lambe
- Department of Chemistry and Biochemistry, University of Arkansas, AR, USA
| | | | - Sarah Piron
- Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
| | - Sam Donche
- Ghent University Hospital, Department of Nuclear Medicine, Ghent, Belgium
| | - Benedicte Descamps
- IBiTech-MEDISIP Ghent University, Department of Electronics and Information Systems, Ghent, Belgium
| | - Ingeborg Goethals
- Ghent University Hospital, Department of Nuclear Medicine, Ghent, Belgium
| | - Christian Vanhove
- IBiTech-MEDISIP Ghent University, Department of Electronics and Information Systems, Ghent, Belgium
| | - Filip De Vos
- Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
| | - M Hassan Beyzavi
- Department of Chemistry and Biochemistry, University of Arkansas, AR, USA.
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Abstract
Drug-induced liver injury, and more specifically drug-induced cholestasis, is responsible for a large amount of hospitalizations and attrition of new drug candidates in preclinical drug development. Drug-induced cholestasis can be triggered by drugs that are inhibitors of the hepatic bile acid transporters. Therefore, it is of considerable interest in preclinical drug development to detect whether new candidate drugs can cause interference with the hepatic bile acid transporters. Although several cost-effective and fast in vitro assays are available to that end, these do not mimic the in vivo situation completely. In vivo research to monitor a new candidate drug's cholestatic potential is still relevant, yet is time-consuming and requires invasive sampling of a lot of laboratory animals. In this chapter, a protocol is provided to determine in vivo inhibition of the hepatic bile acid transporters in mice, using the nuclear imaging techniques positron emission tomography and single photon emission computed tomography. The protocol includes detailed information on preparation of the animal, scan acquisition, processing, and (statistical) analysis.
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Affiliation(s)
- Stef De Lombaerde
- Faculty of Pharmaceutical Sciences, Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium.
| | - Sara Neyt
- Faculty of Pharmaceutical Sciences, Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
| | | | - Filip De Vos
- Faculty of Pharmaceutical Sciences, Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
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Verhoeven J, Hulpia F, Kersemans K, Bolcaen J, De Lombaerde S, Goeman J, Descamps B, Hallaert G, Van den Broecke C, Deblaere K, Vanhove C, Van der Eycken J, Van Calenbergh S, Goethals I, De Vos F. New fluoroethyl phenylalanine analogues as potential LAT1-targeting PET tracers for glioblastoma. Sci Rep 2019; 9:2878. [PMID: 30814660 PMCID: PMC6393465 DOI: 10.1038/s41598-019-40013-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 02/07/2019] [Indexed: 02/07/2023] Open
Abstract
The use of O-(2-[18F]fluoroethyl)-L-tyrosine ([18F]FET) as a positron emission tomography (PET) tracer for brain tumor imaging might have some limitations because of the relatively low affinity for the L-type amino acid transporter 1 (LAT1). To assess the stereospecificity and evaluate the influence of aromatic ring modification of phenylalanine LAT1 targeting tracers, six different fluoroalkylated phenylalanine analogues were synthesized. After in vitro Ki determination, the most promising compound, 2-[18F]-2-fluoroethyl-L-phenylalanine (2-[18F]FELP), was selected for further evaluation and in vitro comparison with [18F]FET. Subsequently, 2-[18F]FELP was assessed in vivo and compared with [18F]FET and [18F]FDG in a F98 glioblastoma rat model. 2-[18F]FELP showed improved in vitro characteristics over [18F]FET, especially when the affinity and specificity for system L is concerned. Based on our results, 2-[18F]FELP is a promising new PET tracer for brain tumor imaging.
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Affiliation(s)
| | - Fabian Hulpia
- Laboratory for Medicinal Chemistry, Ghent University, Ghent, Belgium
| | - Ken Kersemans
- Ghent University Hospital, Department of Nuclear Medicine, Ghent, Belgium
| | - Julie Bolcaen
- Ghent University Hospital, Department of Nuclear Medicine, Ghent, Belgium
| | | | - Jan Goeman
- Laboratory for Organic and Bio-organic synthesis, Ghent University, Ghent, Belgium
| | - Benedicte Descamps
- IBiTech-MEDISIP Ghent University, Department of Electronics and Information Systems, Ghent, Belgium
| | - Giorgio Hallaert
- Ghent University Hospital, Department of Neurosurgery, Ghent, Belgium
| | | | - Karel Deblaere
- Ghent University Hospital, Department of Radiology and Medical Imaging, Ghent, Belgium
| | - Christian Vanhove
- IBiTech-MEDISIP Ghent University, Department of Electronics and Information Systems, Ghent, Belgium
| | - Johan Van der Eycken
- Laboratory for Organic and Bio-organic synthesis, Ghent University, Ghent, Belgium
| | | | - Ingeborg Goethals
- Ghent University Hospital, Department of Nuclear Medicine, Ghent, Belgium
| | - Filip De Vos
- Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
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12
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Ciarrocchi E, Vanhove C, Descamps B, De Lombaerde S, Vandenberghe S, Belcari N. Performance evaluation of the LightPath imaging system for intra-operative Cerenkov luminescence imaging. Phys Med 2018; 52:122-128. [PMID: 30139600 DOI: 10.1016/j.ejmp.2018.07.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 07/13/2018] [Accepted: 07/14/2018] [Indexed: 01/17/2023] Open
Abstract
The performances of an intra-operative optical imaging system for Cerenkov luminescence imaging of resected tumor specimens were evaluated with phantom studies. The spatial resolution, the linearity of the measured signal with the activity concentration and the minimum detectable activity concentration were considered. A high linearity was observed over a broad range of activity concentration (R2⩾0.99 down to ∼40 kBq/ml of 18F-FDG). For 18F-FDG activity distributions 2 mm deep in biological tissue, the measured detection limit was 8 kBq/ml and a spatial resolution of 2.5 mm was obtained. The detection limit of the imaging system is comparable with clinical activity concentrations in tumor specimens, and the spatial resolution is compatible with clinical requirements.
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Affiliation(s)
- Esther Ciarrocchi
- University of Pisa, Department of Physics, Largo Bruno Pontecorvo 3, Pisa 56127, Italy.
| | - Christian Vanhove
- University of Ghent, IBiTech-MEDISIP, C. Heymanslaan 10, Ghent B-9000, Belgium.
| | - Benedicte Descamps
- University of Ghent, IBiTech-MEDISIP, C. Heymanslaan 10, Ghent B-9000, Belgium.
| | - Stef De Lombaerde
- University of Ghent, Faculty of Pharmaceutical Sciences Laboratory of Radiopharmacy, Ottergemsesteenweg 460, Ghent B-9000, Belgium.
| | | | - Nicola Belcari
- University of Pisa, Department of Physics, Largo Bruno Pontecorvo 3, Pisa 56127, Italy.
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De Lombaerde S, Neyt S, Kersemans K, Verhoeven J, Devisscher L, Van Vlierberghe H, Vanhove C, De Vos F. Synthesis, in vitro and in vivo evaluation of 3β-[18F]fluorocholic acid for the detection of drug-induced cholestasis in mice. PLoS One 2017; 12:e0173529. [PMID: 28273180 PMCID: PMC5342262 DOI: 10.1371/journal.pone.0173529] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 02/21/2017] [Indexed: 11/25/2022] Open
Abstract
Introduction Drug-induced cholestasis is a liver disorder that might be caused by interference of drugs with the hepatobiliary bile acid transporters. It is important to identify this interference early on in drug development. In this work, Positron Emission Tomography (PET)-imaging with a 18F labeled bile acid analogue was introduced to detect disturbed hepatobiliary transport of bile acids. Methods 3β-[18F]fluorocholic acid ([18F]FCA) was prepared by nucleophilic substitution of a mesylated precursor with [18F]fluoride, followed by deprotection with sodium hydroxide. Transport of [18F]FCA was assessed in vitro using CHO-NTCP, HEK-OATP1B1, HEK-OATP1B3 transfected cells and BSEP & MRP2 membrane vesicles. Investigation of [18F]FCA metabolites was performed with primary mouse hepatocytes. Hepatobiliary transport of [18F]FCA was evaluated in vivo in wild-type, rifampicin and bosentan pretreated FVB-mice by dynamic μPET scanning. Results Radiosynthesis of [18F]FCA was achieved in a moderate radiochemical yield (8.11 ± 1.94%; non-decay corrected; n = 10) and high radiochemical purity (>99%). FCA was transported by the basolateral bile acid uptake transporters NTCP, OATP1B1 and OATP1B3. For canalicular efflux, BSEP and MRP2 are the relevant bile acid transporters. [18F]FCA was found to be metabolically stable. In vivo, [18F]FCA showed fast hepatic uptake (4.5 ± 0.5 min to reach 71.8 ± 1.2% maximum % ID) and subsequent efflux to the gallbladder and intestines (93.3 ± 6.0% ID after 1 hour). Hepatobiliary transport of [18F]FCA was significantly inhibited by both rifampicin and bosentan. Conclusion A 18F labeled bile acid analogue, [18F]FCA, has been developed that shows transport by NTCP, OATP, MRP2 and BSEP. [18F]FCA can be used as a probe to monitor disturbed hepatobiliary transport in vivo and accumulation of bile acids in blood and liver during drug development.
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Affiliation(s)
- Stef De Lombaerde
- Faculty of Pharmaceutical Sciences, Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
- * E-mail:
| | - Sara Neyt
- Faculty of Pharmaceutical Sciences, Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
| | - Ken Kersemans
- Ghent University Hospital, Nuclear Medicine, Ghent, Belgium
| | - Jeroen Verhoeven
- Faculty of Pharmaceutical Sciences, Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
| | - Lindsey Devisscher
- Ghent University Hospital, Gastroenterology and Hepatology, Ghent, Belgium
| | | | | | - Filip De Vos
- Faculty of Pharmaceutical Sciences, Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium
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14
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Neyt S, Vliegen M, Verreet B, De Lombaerde S, Braeckman K, Vanhove C, Huisman MT, Dumolyn C, Kersemans K, Hulpia F, Van Calenbergh S, Mannens G, De Vos F. Synthesis, in vitro and in vivo small-animal SPECT evaluation of novel technetium labeled bile acid analogues to study (altered) hepatic transporter function. Nucl Med Biol 2016; 43:642-9. [PMID: 27513813 DOI: 10.1016/j.nucmedbio.2016.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 06/19/2016] [Accepted: 07/04/2016] [Indexed: 11/16/2022]
Abstract
INTRODUCTION Hepatobiliary transport mechanisms are crucial for the excretion of substrate toxic compounds. Drugs can inhibit these transporters, which can lead to drug-drug interactions causing toxicity. Therefore, it is important to assess this early during the development of new drug candidates. The aim of the current study is the (radio)synthesis, in vitro and in vivo evaluation of a technetium labeled chenodeoxycholic and cholic acid analogue: [(99m)Tc]-DTPA-CDCA and [(99m)]Tc-DTPA-CA, respectively, as biomarker for disturbed transporter functionality. METHODS [99mTc]-DTPA-CDCA([(99m)Tc]-3a) and [99mTc]-DTPA-CA ([(99m)Tc]-3b) were synthesized and evaluated in vitro and in vivo. Uptake of both tracers was investigated in NTCP, OCT1, OATP1B1, OATP1B3 transfected cell lines. Km and Vmax values were determined and compared to [(99m)Tc]-mebrofenin ([(99m)Tc]-MEB). Efflux was investigated by means of CTRL, MRP2 and BSEP transfected inside-out vesicles. Metabolite analysis was performed using pooled human liver S9. Wild type (n=3) and rifampicin treated (n=3) mice were intravenously injected with 37MBq of tracer. After dynamic small-animal SPECT and short CT acquisitions, time-activity curves of heart, liver, gallbladder and intestines were obtained. RESULTS We demonstrated that OATP1B1 and OATP1B3 are the involved uptake transporters of both compounds. Both tracers show a higher affinity compared to [(99m)Tc]-MEB, but are in a similar range as endogenous bile acids for OATP1B1 and OATP1B3. [(99m)Tc]-3a shows higher affinities compared to [(99m)Tc]-3b. Vmax values were lower compared to [(99m)Tc]-MEB, but in the same range as endogenous bile acids. MRP2 was identified as efflux transporter. Less than 7% of both radiotracers was metabolized in the liver. In vitro results were confirmed by in vivo results. Uptake in the liver and efflux to gallbladder + intestines and urinary bladder of both tracers was observed. Transport was inhibited by rifampicin. CONCLUSION The involved transporters were identified; both tracers are taken up in the hepatocytes by OATP1B1 andOATP1B3 with Km and Vmax values in the same range as endogenous bile acids and are secreted into bile canaliculi via MRP2. Dynamic small-animal SPECT imaging can be a useful noninvasive method of visualizing and quantifying hepatobiliary transporter functionality and disturbances thereof in vivo, which could predict drug pharmacokinetics.
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Affiliation(s)
- Sara Neyt
- Laboratory of Radiopharmacy, Ottergemsesteenweg 460, Ghent University, Ghent, Belgium.
| | - Maarten Vliegen
- Preclinical Development & Safety, Janssen Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Bjorn Verreet
- Preclinical Development & Safety, Janssen Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Stef De Lombaerde
- Laboratory of Radiopharmacy, Ottergemsesteenweg 460, Ghent University, Ghent, Belgium
| | - Kim Braeckman
- iMinds Medical IT-IBITech-MEDISIP-INFINITY, Ghent University, Ghent, Belgium
| | - Christian Vanhove
- iMinds Medical IT-IBITech-MEDISIP-INFINITY, Ghent University, Ghent, Belgium
| | - Maarten Thomas Huisman
- Preclinical Development & Safety, Janssen Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Caroline Dumolyn
- Laboratory of Radiopharmacy, Ottergemsesteenweg 460, Ghent University, Ghent, Belgium
| | - Ken Kersemans
- Laboratory of Radiopharmacy, Ottergemsesteenweg 460, Ghent University, Ghent, Belgium
| | - Fabian Hulpia
- Laboratory for Medicinal Chemistry, Ottergemsesteenweg 460, Ghent University, Ghent, Belgium
| | - Serge Van Calenbergh
- Laboratory for Medicinal Chemistry, Ottergemsesteenweg 460, Ghent University, Ghent, Belgium
| | - Geert Mannens
- Preclinical Development & Safety, Janssen Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Filip De Vos
- Laboratory of Radiopharmacy, Ottergemsesteenweg 460, Ghent University, Ghent, Belgium
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