1
|
Alonso Martinez LM, Harel F, Nguyen QT, Létourneau M, D'Oliviera-Sousa C, Meloche B, Finnerty V, Fournier A, Dupuis J, DaSilva JN. Al[ 18F]F-complexation of DFH17, a NOTA-conjugated adrenomedullin analog, for PET imaging of pulmonary circulation. Nucl Med Biol 2018; 67:36-42. [PMID: 30388434 DOI: 10.1016/j.nucmedbio.2018.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 10/01/2018] [Accepted: 10/11/2018] [Indexed: 01/06/2023]
Abstract
INTRODUCTION Adrenomedullin receptors are highly expressed in human alveolar capillaries and provide a molecular target for imaging the integrity of pulmonary microcirculation. In this work, we aimed to develop a NOTA-derivatized adrenomedullin analog (DFH17), radiolabeled with [18F]AlF, for PET imaging of pulmonary microcirculation. METHODS Highly concentrated [18F](AlF)2+ (15 μL) was produced from purified fluorine-18 in NaCl 0.9%. Various complexation experiments were carried out at Al-to-NOTA molar ratios ranging from 1:1 to 1:40 to assess optimal radiolabeling conditions before using the peptide. DFH17 peptide (2 mM, pH 4) was radiolabeled with [18F](AlF)2+ for 15 min at 100 °C in a total volume of 60 μL. As part of the radiolabeling process, parameters such as fluorine-18 activity (~37 and 1480 MBq), concentration of AlCl3 (0.75, 2, 3, 6 or 10 mM) and the effects of hydrophilic organic solvent (aqueous vs ethanol 50%) were studied. The final formulation was tested for purity, identity and stability in saline. Initial in vivo evaluation of [18F]AlF-DFH17 was performed in normal rats by PET/CT. RESULTS The scaled-up production of [18F]AlF-DFH17 was performed in high radiochemical and chemical purities in an overall radiochemical yield of 22-38% (at end-of-synthesis) within 60 min. The final formulation was stable in saline at different radioactive concentrations for 8 h. PET evaluation in rats revealed high lung-to-background ratios and no defluorination in vivo up to 1 h post-injection. CONCLUSION The novel radioconjugate [18F]AlF-DFH17 appears to be a promising PET ligand for pulmonary microcirculation imaging.
Collapse
Affiliation(s)
- Luis Michel Alonso Martinez
- University of Montreal Hospital Research Centre, 900 rue Saint-Denis, Montréal, Québec H2X 3H8, Canada; Department of Biomedical Engineering, Faculty of Medicine, Université de Montréal, Pavillon Paul-G. Desmarais, 2960 chemin de la Tour, Montréal, Québec H3T 1J4, Canada; Research Center of the Montreal Heart Institute, 5000 Rue Bélanger, Montréal, Québec H1T 1C8, Canada
| | - François Harel
- Department of Biomedical Engineering, Faculty of Medicine, Université de Montréal, Pavillon Paul-G. Desmarais, 2960 chemin de la Tour, Montréal, Québec H3T 1J4, Canada; Research Center of the Montreal Heart Institute, 5000 Rue Bélanger, Montréal, Québec H1T 1C8, Canada; Department of Radiology, Radio-oncology and Nuclear Medicine, Université de Montréal, Pavillon Roger-Gaudry, 2900 Boulevard Edouard Montpetit, Montréal, Québec H3T 1J4, Canada
| | - Quang T Nguyen
- Research Center of the Montreal Heart Institute, 5000 Rue Bélanger, Montréal, Québec H1T 1C8, Canada
| | - Myriam Létourneau
- Laboratoire D'études Moléculaires et Pharmacologiques des Peptides, INRS-Institut Armand-Frappier, 531 boulevard des Prairies, Laval, Québec H7V 1B7, Canada
| | - Caroline D'Oliviera-Sousa
- Research Center of the Montreal Heart Institute, 5000 Rue Bélanger, Montréal, Québec H1T 1C8, Canada
| | - Bernard Meloche
- Research Center of the Montreal Heart Institute, 5000 Rue Bélanger, Montréal, Québec H1T 1C8, Canada
| | - Vincent Finnerty
- Research Center of the Montreal Heart Institute, 5000 Rue Bélanger, Montréal, Québec H1T 1C8, Canada
| | - Alain Fournier
- Department of Radiology, Radio-oncology and Nuclear Medicine, Université de Montréal, Pavillon Roger-Gaudry, 2900 Boulevard Edouard Montpetit, Montréal, Québec H3T 1J4, Canada
| | - Jocelyn Dupuis
- Research Center of the Montreal Heart Institute, 5000 Rue Bélanger, Montréal, Québec H1T 1C8, Canada; Department of Medicine, Université de Montréal, 2900 boulevard Edouard Montpetit, Montréal, Québec H3T 1J4, Canada
| | - Jean N DaSilva
- University of Montreal Hospital Research Centre, 900 rue Saint-Denis, Montréal, Québec H2X 3H8, Canada; Department of Biomedical Engineering, Faculty of Medicine, Université de Montréal, Pavillon Paul-G. Desmarais, 2960 chemin de la Tour, Montréal, Québec H3T 1J4, Canada; Department of Radiology, Radio-oncology and Nuclear Medicine, Université de Montréal, Pavillon Roger-Gaudry, 2900 Boulevard Edouard Montpetit, Montréal, Québec H3T 1J4, Canada.
| |
Collapse
|
2
|
Harel F, Levac X, Nguyen QT, Létourneau M, Marcil S, Finnerty V, Cossette M, Fournier A, Dupuis J. Molecular imaging of the human pulmonary vascular endothelium using an adrenomedullin receptor ligand. Mol Imaging 2015; 14:7290201500003. [PMID: 25812438 DOI: 10.2310/7290.2015.00003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This phase I study (NCT01539889) evaluated the safety, efficacy, and dosing of PulmoBind for molecular imaging of pulmonary circulation. PulmoBind is a ligand of the adrenomedullin receptor abundantly distributed in lung capillaries. Labeled with 99mTc, it allows single-photon emission computed tomographic (SPECT) imaging of lung perfusion. In preclinical studies, PulmoBind scans enabled detection of lung perfusion defects and quantification of microcirculatory occlusion caused by pulmonary hypertension. Healthy humans (N = 20) were included into escalating groups of 5 mCi (n = 5), 10 mCi (n = 5), or 15 mCi (n = 10) 99mTc-PulmoBind. SPECT imaging was serially performed, and 99mTc-PulmoBind dosimetric analysis was accomplished. The radiochemical purity of 99mTc-PulmoBind was greater than 95%. There were no safety concerns at the three dosages studied. Imaging revealed predominant and prolonged lung uptake with a mean peak extraction of 58% ± 7%. PulmoBind was well tolerated, with no clinically significant adverse event related to the study drug. The highest dose of 15 mCi provided a favorable dosimetric profile and excellent imaging. The postural lung perfusion gradient was detectable. 99mTc-PulmoBind is safe and provides good quality lung perfusion imaging. The safety/efficacy of this agent can be tested in disorders of pulmonary circulation such as pulmonary arterial hypertension.
Collapse
|
3
|
Dupuis J, Harel F, Nguyen QT. Molecular imaging of the pulmonary circulation in health and disease. Clin Transl Imaging 2014; 2:415-426. [PMID: 25360422 PMCID: PMC4209091 DOI: 10.1007/s40336-014-0076-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 08/15/2014] [Indexed: 11/29/2022]
Abstract
The pulmonary circulation, at the unique crossroads between the left and the right heart, is submitted to large physiologic hemodynamic variations and possesses numerous important metabolic functions mediated through its vast endothelial surface. There are many pathologic conditions that can directly or indirectly affect the pulmonary vasculature and modify its physiology and functions. Pulmonary hypertension, the end result of many of these affections, is unfortunately diagnosed too late in the disease process, meaning that there is a crying need for earlier diagnosis and surrogate markers of disease progression and regression. By targeting endothelial, medial and adventitial targets of the pulmonary vasculature, novel molecular imaging agents could provide early detection of physiologic and biologic perturbation in the pulmonary circulation. This review provides the rationale for the development of molecular imaging agents for the diagnosis and follow-up of disorders of the pulmonary circulation and discusses promising targets for SPECT and positron emission tomographic imaging.
Collapse
Affiliation(s)
- Jocelyn Dupuis
- Research Center, Montreal Heart Institute, 5000 Belanger Street, Montreal, QC H1T 1C8 Canada ; Department of Medicine, Université de Montréal, Montreal, QC Canada
| | - François Harel
- Research Center, Montreal Heart Institute, 5000 Belanger Street, Montreal, QC H1T 1C8 Canada ; Department of Radiology, Radio-Oncology and Nuclear Medicine Université de Montréal, Montreal, QC Canada
| | - Quang T Nguyen
- Research Center, Montreal Heart Institute, 5000 Belanger Street, Montreal, QC H1T 1C8 Canada
| |
Collapse
|
5
|
Fu Y, Létourneau M, Chatenet D, Dupuis J, Fournier A. Characterization of iodinated adrenomedullin derivatives suitable for lung nuclear medicine. Nucl Med Biol 2011; 38:867-74. [PMID: 21843783 DOI: 10.1016/j.nucmedbio.2011.01.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 01/14/2011] [Accepted: 01/29/2011] [Indexed: 02/02/2023]
Abstract
INTRODUCTION We have recently demonstrated the effectiveness of 99m-technetium adrenomedullin (AM) as a new molecular lung imaging agent that could provide significant advantages for the diagnosis and follow-up of disorders affecting the pulmonary circulation such as pulmonary embolism and pulmonary hypertension. Having the possibility to conjugate the targeting molecule with different radionuclides would offer more flexibility and potential advantages depending on clinical situations. Since various iodine isotopes are currently used in nuclear medicine and in pharmacological studies, we have evaluated which iodination method should be privileged in order to produce a good iodinated AM-derived nuclear medicine agent. METHODS Synthetic AM was labeled with iodine through chemical and lactoperoxidase oxidation methods. Position of the iodine atom on the peptide was determined by MALDI-TOF mass spectrometry analysis following cyanogen bromide cleavage and carboxypeptidase Y digestion. Binding affinity of iodinated AM analogues was evaluated by competition and saturation binding experiments on dog lung preparations. RESULTS In this study, we demonstrated that, upon lactoperoxidase oxidation, iodination occurred at Tyr(1) and that this radioligand retained higher binding affinity and specificity over preparations obtained through chemical oxidation. CONCLUSIONS These results emphasize the fact that even a small chemical modification, i.e. iodination, might deeply modify the pharmacological profile of a compound and support observations that the C-terminal tail of human AM plays an important role in the AM receptor binding process. Consequently, incorporation of a radionuclide to produce an AM-based nuclear medicine agent should privilege the N-terminus of the molecule.
Collapse
Affiliation(s)
- Yan Fu
- Laboratoire d'Études Moléculaires et Pharmacologiques des Peptides, INRS-Institut Armand-Frappier, Ville de Laval, Qc, Canada
| | | | | | | | | |
Collapse
|
7
|
Aufort M, Gonera M, Lelait MA, Czarny B, Le Clainche L, Thaï R, Landra A, Ruinart de Brimont M, Dugave C. Synthesis, in vitro screening and in vivo evaluation of cyclic RGD analogs cyclized through oxorhenium and oxotechnetium coordination. Eur J Med Chem 2011; 46:1779-88. [PMID: 21392860 DOI: 10.1016/j.ejmech.2011.02.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 02/10/2011] [Accepted: 02/11/2011] [Indexed: 12/13/2022]
Abstract
A library of RGD tripeptide analogs cyclized through oxorhenium coordination by an NS2/S chelation motif was synthesized. Screening towards integrins αVβ3, αIIbβ3 and αVβ5 led to the identification of 6 oxorhenium complexes that bind to integrin αVβ3 in the submicromolar range. In vivo evaluation of five of the corresponding oxotechnetium complexes using nude mice bearing a U87MG human tumor xenograft showed a significant and specific accumulation of radioactivity inside the tumor. The best results in vivo were obtained with complexes Tc-16 and Tc-50 that displayed a higher tumor accumulation and a lower distribution in other tissues relative to a reference cyclopentapeptide tracer.
Collapse
Affiliation(s)
- Marie Aufort
- CEA/Saclay, iBiTec-S/SIMOPRO, Bâtiment 152, 91191 Gif-sur-Yvette, France
| | | | | | | | | | | | | | | | | |
Collapse
|