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Schlein E, Rokka J, Odell LR, van den Broek SL, Herth MM, Battisti UM, Syvänen S, Sehlin D, Eriksson J. Synthesis and evaluation of fluorine-18 labelled tetrazines as pre-targeting imaging agents for PET. EJNMMI Radiopharm Chem 2024; 9:21. [PMID: 38446356 PMCID: PMC10917718 DOI: 10.1186/s41181-024-00250-6] [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: 02/04/2024] [Accepted: 02/28/2024] [Indexed: 03/07/2024] Open
Abstract
BACKGROUND The brain is a challenging target for antibody-based positron emission tomography (immunoPET) imaging due to the restricted access of antibody-based ligands through the blood-brain barrier (BBB). To overcome this physiological obstacle, we have previously developed bispecific antibody ligands that pass through the BBB via receptor-mediated transcytosis. While these radiolabelled ligands have high affinity and specificity, their long residence time in the blood and brain, typical for large molecules, poses another challenge for PET imaging. A viable solution could be a two-step pre-targeting approach which involves the administration of a tagged antibody that accumulates at the target site in the brain and then clears from the blood, followed by administration of a small radiolabelled molecule with fast kinetics. This radiolabelled molecule can couple to the tagged antibody and thereby make the antibody localisation visible by PET imaging. The in vivo linkage can be achieved by using the inverse electron demand Diels-Alder reaction (IEDDA), with trans-cyclooctene (TCO) and tetrazine groups participating as reactants. In this study, two novel 18F-labelled tetrazines were synthesized and evaluated for their potential use as pre-targeting imaging agents, i.e., for their ability to rapidly enter the brain and, if unbound, to be efficiently cleared with minimal background retention. RESULTS The two compounds, a methyl tetrazine [18F]MeTz and an H-tetrazine [18F]HTz were radiolabelled using a two-step procedure via [18F]F-Py-TFP synthesized on solid support followed by amidation with amine-bearing tetrazines, resulting in radiochemical yields of 24% and 22%, respectively, and a radiochemical purity of > 96%. In vivo PET imaging was performed to assess their suitability for in vivo pre-targeting. Time-activity curves from PET-scans showed [18F]MeTz to be the more pharmacokinetically suitable agent, given its fast and homogenous distribution in the brain and rapid clearance. However, in terms of rection kinetics, H-tetrazines are advantageous, exhibiting faster reaction rates in IEDDA reactions with dienophiles like trans-cyclooctenes, making [18F]HTz potentially more beneficial for pre-targeting applications. CONCLUSION This study demonstrates a significant potential of [18F]MeTz and [18F]HTz as agents for pre-targeted PET brain imaging due to their efficient brain uptake, swift clearance and appropriate chemical stability.
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Affiliation(s)
- Eva Schlein
- Department of Public Health and Caring Sciences, Uppsala University, 751 85, Uppsala, Sweden
| | - Johanna Rokka
- Department of Public Health and Caring Sciences, Uppsala University, 751 85, Uppsala, Sweden
| | - Luke R Odell
- Department of Medicinal Chemistry, Uppsala University, 751 23, Uppsala, Sweden
| | | | - Matthias M Herth
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100, Copenhagen, Denmark
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet Copenhagen University Hospital, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Umberto M Battisti
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100, Copenhagen, Denmark
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, 751 85, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, 751 85, Uppsala, Sweden
| | - Jonas Eriksson
- Department of Medicinal Chemistry, Uppsala University, 751 23, Uppsala, Sweden.
- PET Centre, Uppsala University Hospital, 751 85, Uppsala, Sweden.
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Bonvicini G, Bagawath Singh S, Nygren P, Xiong M, Syvänen S, Sehlin D, Falk R, Andersson KG. Comparing in vitro affinity measurements of antibodies to TfR1: Surface plasmon resonance versus on-cell affinity. Anal Biochem 2024; 686:115406. [PMID: 38006952 DOI: 10.1016/j.ab.2023.115406] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 11/13/2023] [Accepted: 11/18/2023] [Indexed: 11/27/2023]
Abstract
Despite years of utilizing the transferrin receptor 1 (TfR1) to transport large biomolecules into the brain, there is no consensus on how to optimally measure affinity to it. The aim of this study was to compare different methods for measuring the affinities of anti-TfR1 antibodies. Antibodies 15G11, OX26 and 8D3 are known to successfully carry large biologics across the blood-brain barrier in humans, rats, and mice, respectively. The affinity to their respective species of TfR1 was measured with different surface plasmon resonance setups in Biacore and an on-cell assay. When the antibody was captured and TfR1 was the analyte, the dissociation in Biacore was very slow. The dissociation was faster when the antibody was the analyte and TfR1 was the ligand. The Biacore setup with capture of N-terminal FLAG-tag TfR1 yielded the most similar apparent affinities as the cell assay. In conclusion, it is important to evaluate assay parameters including assay orientation, surface capture method, and antibody-format when comparing binding kinetics for TfR1 antibodies. Although it seems possible to determine relative affinities of TfR1 antibodies using the methods described here, both the FLAG-tag TfR1 capture setup and cell assays likely yield apparent affinities that are most translatable in vivo.
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Affiliation(s)
- Gillian Bonvicini
- BioArctic AB, Warfvinges väg 35, SE-112 51, Stockholm, Sweden; Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, SE-751 85, Uppsala, Sweden
| | | | - Patrik Nygren
- BioArctic AB, Warfvinges väg 35, SE-112 51, Stockholm, Sweden
| | - Mengfei Xiong
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, SE-751 85, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, SE-751 85, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, SE-751 85, Uppsala, Sweden
| | - Ronny Falk
- BioArctic AB, Warfvinges väg 35, SE-112 51, Stockholm, Sweden
| | - Ken G Andersson
- BioArctic AB, Warfvinges väg 35, SE-112 51, Stockholm, Sweden.
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3
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Beretta C, Svensson E, Dakhel A, Zyśk M, Hanrieder J, Sehlin D, Michno W, Erlandsson A. Amyloid-β deposits in human astrocytes contain truncated and highly resistant proteoforms. Mol Cell Neurosci 2024; 128:103916. [PMID: 38244652 DOI: 10.1016/j.mcn.2024.103916] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 01/08/2024] [Accepted: 01/15/2024] [Indexed: 01/22/2024] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder that develops over decades. Glial cells, including astrocytes are tightly connected to the AD pathogenesis, but their impact on disease progression is still unclear. Our previous data show that astrocytes take up large amounts of aggregated amyloid-beta (Aβ) but are unable to successfully degrade the material, which is instead stored intracellularly. The aim of the present study was to analyze the astrocytic Aβ deposits composition in detail in order to understand their role in AD propagation. For this purpose, human induced pluripotent cell (hiPSC)-derived astrocytes were exposed to sonicated Aβ42 fibrils and magnetic beads. Live cell imaging and immunocytochemistry confirmed that the ingested Aβ aggregates and beads were transported to the same lysosomal compartments in the perinuclear region, which allowed us to successfully isolate the Aβ deposits from the astrocytes. Using a battery of experimental techniques, including mass spectrometry, western blot, ELISA and electron microscopy we demonstrate that human astrocytes truncate and pack the Aβ aggregates in a way that makes them highly resistant. Moreover, the astrocytes release specifically truncated forms of Aβ via different routes and thereby expose neighboring cells to pathogenic proteins. Taken together, our study establishes a role for astrocytes in mediating Aβ pathology, which could be of relevance for identifying novel treatment targets for AD.
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Affiliation(s)
- C Beretta
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-752 37 Uppsala, Sweden.
| | - E Svensson
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-752 37 Uppsala, Sweden; Department of Neuroinflammation, UCL Queen Square Institute of Neurology, 1 Wakefield Street, WC1N 1PJ London, United Kingdom of Great Britain and Northern Ireland.
| | - A Dakhel
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-752 37 Uppsala, Sweden.
| | - M Zyśk
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-752 37 Uppsala, Sweden.
| | - J Hanrieder
- Department of Psychiatry and Neurochemistry, University of Gothenburg, SE-43180 Gothenburg, Sweden.
| | - D Sehlin
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-752 37 Uppsala, Sweden.
| | - W Michno
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-752 37 Uppsala, Sweden; Science for Life Laboratory, Uppsala University, SE-752 37 Uppsala, Sweden.
| | - A Erlandsson
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-752 37 Uppsala, Sweden.
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Pagnon de la Vega M, Syvänen S, Giedraitis V, Hooley M, Konstantinidis E, Meier SR, Rokka J, Eriksson J, Aguilar X, Spires-Jones TL, Lannfelt L, Nilsson LNG, Erlandsson A, Hultqvist G, Ingelsson M, Sehlin D. Altered amyloid-β structure markedly reduces gliosis in the brain of mice harboring the Uppsala APP deletion. Acta Neuropathol Commun 2024; 12:22. [PMID: 38317196 PMCID: PMC10845526 DOI: 10.1186/s40478-024-01734-x] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 01/14/2024] [Indexed: 02/07/2024] Open
Abstract
Deposition of amyloid beta (Aβ) into plaques is a major hallmark of Alzheimer's disease (AD). Different amyloid precursor protein (APP) mutations cause early-onset AD by altering the production or aggregation properties of Aβ. We recently identified the Uppsala APP mutation (APPUpp), which causes Aβ pathology by a triple mechanism: increased β-secretase and altered α-secretase APP cleavage, leading to increased formation of a unique Aβ conformer that rapidly aggregates and deposits in the brain. The aim of this study was to further explore the effects of APPUpp in a transgenic mouse model (tg-UppSwe), expressing human APP with the APPUpp mutation together with the APPSwe mutation. Aβ pathology was studied in tg-UppSwe brains at different ages, using ELISA and immunohistochemistry. In vivo PET imaging with three different PET radioligands was conducted in aged tg-UppSwe mice and two other mouse models; tg-ArcSwe and tg-Swe. Finally, glial responses to Aβ pathology were studied in cell culture models and mouse brain tissue, using ELISA and immunohistochemistry. Tg-UppSwe mice displayed increased β-secretase cleavage and suppressed α-secretase cleavage, resulting in AβUpp42 dominated diffuse plaque pathology appearing from the age of 5-6 months. The γ-secretase cleavage was not affected. Contrary to tg-ArcSwe and tg-Swe mice, tg-UppSwe mice were [11C]PiB-PET negative. Antibody-based PET with the 3D6 ligand visualized Aβ pathology in all models, whereas the Aβ protofibril selective mAb158 ligand did not give any signals in tg-UppSwe mice. Moreover, unlike the other two models, tg-UppSwe mice displayed a very faint glial response to the Aβ pathology. The tg-UppSwe mouse model thus recapitulates several pathological features of the Uppsala APP mutation carriers. The presumed unique structural features of AβUpp42 aggregates were found to affect their interaction with anti-Aβ antibodies and profoundly modify the Aβ-mediated glial response, which may be important aspects to consider for further development of AD therapies.
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Affiliation(s)
- María Pagnon de la Vega
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Vilmantas Giedraitis
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Monique Hooley
- UK Dementia Research Institute, Edinburgh Medical School, University of Edinburgh, Edinburgh, UK
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Evangelos Konstantinidis
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Silvio R Meier
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Johanna Rokka
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Jonas Eriksson
- Department of Medicinal Chemistry, Division of Organic Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
- PET Centre, Uppsala University Hospital, Uppsala, Sweden
| | - Ximena Aguilar
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Tara L Spires-Jones
- UK Dementia Research Institute, Edinburgh Medical School, University of Edinburgh, Edinburgh, UK
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
- BioArctic AB, Stockholm, Sweden
| | - Lars N G Nilsson
- Department of Pharmacology, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Anna Erlandsson
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | | | - Martin Ingelsson
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Tanz Centre for Research in Neurodegenerative Diseases, Departments of Medicine and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden.
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5
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Schlein E, Andersson KG, Dallas T, Syvänen S, Sehlin D. Reducing neonatal Fc receptor binding enhances clearance and brain-to-blood ratio of TfR-delivered bispecific amyloid-β antibody. MAbs 2024; 16:2339337. [PMID: 38634473 PMCID: PMC11028011 DOI: 10.1080/19420862.2024.2339337] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Accepted: 04/02/2024] [Indexed: 04/19/2024] Open
Abstract
Recent development of amyloid-β (Aβ)-targeted immunotherapies for Alzheimer's disease (AD) have highlighted the need for accurate diagnostic methods. Antibody-based positron emission tomography (PET) ligands are well suited for this purpose as they can be directed toward the same target as the therapeutic antibody. Bispecific, brain-penetrating antibodies can achieve sufficient brain concentrations, but their slow blood clearance remains a challenge, since it prolongs the time required to achieve a target-specific PET signal. Here, two antibodies were designed based on the Aβ antibody bapineuzumab (Bapi) - one monospecific IgG (Bapi) and one bispecific antibody with an antigen binding fragment (Fab) of the transferrin receptor (TfR) antibody 8D3 fused to one of the heavy chains (Bapi-Fab8D3) for active, TfR-mediated transport into the brain. A variant of each antibody was designed to harbor a mutation to the neonatal Fc receptor (FcRn) binding domain, to increase clearance. Blood and brain pharmacokinetics of radiolabeled antibodies were studied in wildtype (WT) and AD mice (AppNL-G-F). The FcRn mutation substantially reduced blood half-life of both Bapi and Bapi-Fab8D3. Bapi-Fab8D3 showed high brain uptake and the brain-to-blood ratio of its FcRn mutated form was significantly higher in AppNL-G-F mice than in WT mice 12 h after injection and increased further up to 168 h. Ex vivo autoradiography showed specific antibody retention in areas with abundant Aβ pathology. Taken together, these results suggest that reducing FcRn binding of a full-sized bispecific antibody increases the systemic elimination and could thereby drastically reduce the time from injection to in vivo imaging.
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Affiliation(s)
- Eva Schlein
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | | | - Tiffany Dallas
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
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6
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Zielinski M, Peralta Reyes FS, Gremer L, Schemmert S, Frieg B, Schäfer LU, Willuweit A, Donner L, Elvers M, Nilsson LNG, Syvänen S, Sehlin D, Ingelsson M, Willbold D, Schröder GF. Cryo-EM of Aβ fibrils from mouse models find tg-APP ArcSwe fibrils resemble those found in patients with sporadic Alzheimer's disease. Nat Neurosci 2023; 26:2073-2080. [PMID: 37973869 PMCID: PMC10689242 DOI: 10.1038/s41593-023-01484-4] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 10/06/2023] [Indexed: 11/19/2023]
Abstract
The use of transgenic mice displaying amyloid-β (Aβ) brain pathology has been essential for the preclinical assessment of new treatment strategies for Alzheimer's disease. However, the properties of Aβ in such mice have not been systematically compared to Aβ in the brains of patients with Alzheimer's disease. Here, we determined the structures of nine ex vivo Aβ fibrils from six different mouse models by cryogenic-electron microscopy. We found novel Aβ fibril structures in the APP/PS1, ARTE10 and tg-SwDI models, whereas the human type II filament fold was found in the ARTE10, tg-APPSwe and APP23 models. The tg-APPArcSwe mice showed an Aβ fibril whose structure resembles the human type I filament found in patients with sporadic Alzheimer's disease. A detailed assessment of the Aβ fibril structure is key to the selection of adequate mouse models for the preclinical development of novel plaque-targeting therapeutics and positron emission tomography imaging tracers in Alzheimer's disease.
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Affiliation(s)
- Mara Zielinski
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Jülich, Germany
- JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany
| | | | - Lothar Gremer
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Jülich, Germany.
- JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
| | - Sarah Schemmert
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Jülich, Germany
| | - Benedikt Frieg
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Jülich, Germany
- JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany
| | - Luisa U Schäfer
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Jülich, Germany
- JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany
- Life and Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany
| | - Antje Willuweit
- Institute of Neuroscience and Medicine, Medical Imaging Physics (INM-4), Forschungszentrum Jülich, Jülich, Germany
| | - Lili Donner
- Department of Vascular and Endovascular Surgery, University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
| | - Margitta Elvers
- Department of Vascular and Endovascular Surgery, University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
| | - Lars N G Nilsson
- Department of Pharmacology, Institute of Clinical Medicine, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Martin Ingelsson
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
- Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada
- Tanz Centre for Research in Neurodegenerative Diseases, Departments of Medicine and Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Dieter Willbold
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Jülich, Germany.
- JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
| | - Gunnar F Schröder
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Jülich, Germany.
- JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany.
- Physics Department, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
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7
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Xiong M, Roshanbin S, Sehlin D, Hansen HD, Knudsen GM, Rokka J, Eriksson J, Syvänen S. Synaptic density in aging mice measured by [ 18F]SynVesT-1 PET. Neuroimage 2023:120230. [PMID: 37355199 DOI: 10.1016/j.neuroimage.2023.120230] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 05/03/2023] [Accepted: 06/14/2023] [Indexed: 06/26/2023] Open
Abstract
Synaptic alterations in certain brain structures are related to cognitive decline in neurodegeneration and in aging. Synaptic loss in many neurodegenerative diseases can be visualized by positron emission tomography (PET) imaging of synaptic vesicle glycoprotein 2A (SV2A). However, the use of SV2A PET for studying synaptic changes during aging is not particularly explored. Thus, in the present study, PET ligand [18F]SynVesT-1, which binds to SV2A, was used to investigate synaptic density at different ages in healthy mice. Wild type C57BL/6 mice divided into three age groups (4-5 months (n = 7), 12-14 months (n = 11), 17-19 months (n = 7)) were PET scanned with [18F]SynVesT-1. Brain retention of [18F]SynVesT-1 expressed as the volume of distribution (VIDIF) was calculated using an image-derived input function. Estimates of VIDIF were derived using either a one-tissue compartment model (1TCM), a two-tissue compartment model (2TCM), or the Logan plot with blood input to find the best-fit model for [18F]SynVesT-1. After the PET scans, tissue sections were immunostained for the detection of SV2A and neuronal markers. We found that [18F]SynVesT-1 data acquired 60 min post intravenously injection and analyzed with 1TCM described the brain pharmacokinetics of the radioligand in mice well. [18F]SynVesT-1 brain retention was lower in the oldest group of mice, indicating a decrease in synaptic density in this age group. However, no gradual age-dependent decrease in synaptic density at a region-specific level was observed. Immunostaining indicated that SV2A expression and neuron numbers were similar across all three age groups. In general, these data obtained in healthy aging mice are consistent with previous findings in humans where synaptic density appeared stable during aging up to a certain age, after which a small decrease is observed.
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Affiliation(s)
- Mengfei Xiong
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, SE-751 85 Uppsala, Sweden
| | - Sahar Roshanbin
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, SE-751 85 Uppsala, Sweden
| | - Dag Sehlin
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, SE-751 85 Uppsala, Sweden
| | - Hanne D Hansen
- Neurobiology Research Unit, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark; Department of Clinical Medicine, University of Copenhagen, Denmark
| | - Johanna Rokka
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, SE-751 85 Uppsala, Sweden
| | - Jonas Eriksson
- PET Centre, Uppsala University Hospital, SE-751 85 Uppsala, Sweden; Department of Medicinal Chemistry, Uppsala University, SE-751 23 Uppsala, Sweden
| | - Stina Syvänen
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, SE-751 85 Uppsala, Sweden.
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8
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Faresjö R, Sehlin D, Syvänen S. Age, dose, and binding to TfR on blood cells influence brain delivery of a TfR-transported antibody. Fluids Barriers CNS 2023; 20:34. [PMID: 37170266 PMCID: PMC10173660 DOI: 10.1186/s12987-023-00435-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 12/22/2022] [Accepted: 04/27/2023] [Indexed: 05/13/2023] Open
Abstract
BACKGROUND Transferrin receptor 1 (TfR1) mediated brain delivery of antibodies could become important for increasing the efficacy of emerging immunotherapies in Alzheimer's disease (AD). However, age, dose, binding to TfR1 on blood cells, and pathology could influence the TfR1-mediated transcytosis of TfR1-binders across the blood-brain barrier (BBB). The aim of the study was, therefore, to investigate the impact of these factors on the brain delivery of a bispecific TfR1-transported Aβ-antibody, mAb3D6-scFv8D3, in comparison with the conventional antibody mAb3D6. METHODS Young (3-5 months) and aged (17-20 months) WT and tg-ArcSwe mice (AD model) were injected with 125I-labeled mAb3D6-scFv8D3 or mAb3D6. Three different doses were used in the study, 0.05 mg/kg (low dose), 1 mg/kg (high dose), and 10 mg/kg (therapeutic dose), with equimolar doses for mAb3D6. The dose-corrected antibody concentrations in whole blood, blood cells, plasma, spleen, and brain were evaluated at 2 h post-administration. Furthermore, isolated brains were studied by autoradiography, nuclear track emulsion, and capillary depletion to investigate the intrabrain distribution of the antibodies, while binding to blood cells was studied in vitro using blood isolated from young and aged mice. RESULTS The aged WT and tg-ArcSwe mice showed significantly lower brain concentrations of TfR-binding [125I]mAb3D6-scFv8D3 and higher concentrations in the blood cell fraction compared to young mice. For [125I]mAb3D6, no significant differences in blood or brain delivery were observed between young and aged mice or between genotypes. A low dose of [125I]mAb3D6-scFv8D3 was associated with increased relative parenchymal delivery, as well as increased blood cell distribution. Brain concentrations and relative parenchymal distribution of [125I]mAb3D6-scFv8D6 did not differ between tg-ArcSwe and WT mice at this early time point but were considerably increased compared to those observed for [125I]mAb3D6. CONCLUSION Age-dependent differences in blood and brain concentrations were observed for the bispecific antibody mAb3D6-scFv8D3 but not for the conventional Aβ antibody mAb3D6, indicating an age-related effect on TfR1-mediated brain delivery. The lowest dose of [125I]mAb3D6-scFv8D3 was associated with higher relative BBB penetration but, at the same time, a higher distribution to blood cells. Overall, Aβ-pathology did not influence the early brain distribution of the bispecific antibody. In summary, age and bispecific antibody dose were important factors determining brain delivery, while genotype was not.
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Affiliation(s)
- Rebecca Faresjö
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden.
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9
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Banka V, Kelleher A, Sehlin D, Hultqvist G, Sigurdsson EM, Syvänen S, Ding YS. Development of brain-penetrable antibody radioligands for in vivo PET imaging of amyloid-β and tau. Front Nucl Med 2023; 3:1173693. [PMID: 37680310 PMCID: PMC10483511 DOI: 10.3389/fnume.2023.1173693] [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] [Subscribe] [Scholar Register] [Indexed: 09/09/2023]
Abstract
Introduction Alzheimer's disease (AD) is characterized by the misfolding and aggregation of two major proteins: amyloid-beta (Aβ) and tau. Antibody-based PET radioligands are desirable due to their high specificity and affinity; however, antibody uptake in the brain is limited by the blood-brain barrier (BBB). Previously, we demonstrated that antibody transport across the BBB can be facilitated through interaction with the transferrin receptor (TfR), and the bispecific antibody-based PET ligands were capable of detecting Aβ aggregates via ex vivo imaging. Since tau accumulation in the brain is more closely correlated with neuronal death and cognition, we report here our strategies to prepare four F-18-labeled specifically engineered bispecific antibody probes for the selective detection of tau and Aβ aggregates to evaluate their feasibility and specificity, particularly for in vivo PET imaging. Methods We first created and evaluated (via both in vitro and ex vivo studies) four specifically engineered bispecific antibodies, by fusion of single-chain variable fragments (scFv) of a TfR antibody with either a full-size IgG antibody of Aβ or tau or with their respective scFv. Using [18F]SFB as the prosthetic group, all four 18F-labeled bispecific antibody probes were then prepared by conjugation of antibody and [18F]SFB in acetonitrile/0.1 M borate buffer solution (final pH ~ 8.5) with an incubation of 20 min at room temperature, followed by purification on a PD MiniTrap G-25 size exclusion gravity column. Results Based on both in vitro and ex vivo evaluation, the bispecific antibodies displayed much higher brain concentrations than the unmodified antibody, supporting our subsequent F18-radiolabeling. [18F]SFB was produced in high yields in 60 min (decay-corrected radiochemical yield (RCY) 46.7 ± 5.4) with radiochemical purities of >95%, confirmed by analytical high performance liquid chromatography (HPLC) and radio-TLC. Conjugation of [18F]SFB and bispecific antibodies showed a 65%-83% conversion efficiency with radiochemical purities of 95%-99% by radio-TLC. Conclusions We successfully labeled four novel and specifically engineered bispecific antibodies with [18F]SFB under mild conditions with a high RCY and purities. This study provides strategies to create brain-penetrable F-18 radiolabeled antibody probes for the selective detection of tau and Aβ aggregates in the brain of transgenic AD mice via in vivo PET imaging.
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Affiliation(s)
- Vinay Banka
- Department of Radiology, New York University School of
Medicine, New York, NY, United States
| | - Andrew Kelleher
- Department of Radiology, New York University School of
Medicine, New York, NY, United States
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala
University, Uppsala, Sweden
| | | | - Einar M. Sigurdsson
- Department of Psychiatry, New York University School of
Medicine, New York, NY, United States
- Department of Neuroscience and Physiology, New York
University School of Medicine, New York, NY, United States
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala
University, Uppsala, Sweden
| | - Yu-Shin Ding
- Department of Radiology, New York University School of
Medicine, New York, NY, United States
- Department of Psychiatry, New York University School of
Medicine, New York, NY, United States
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10
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Gustavsson T, Metzendorf NG, Wik E, Roshanbin S, Julku U, Chourlia A, Nilsson P, Andersson KG, Laudon H, Hultqvist G, Syvänen S, Sehlin D. Long-term effects of immunotherapy with a brain penetrating Aβ antibody in a mouse model of Alzheimer's disease. Alzheimers Res Ther 2023; 15:90. [PMID: 37131196 PMCID: PMC10152635 DOI: 10.1186/s13195-023-01236-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 03/01/2023] [Accepted: 04/23/2023] [Indexed: 05/04/2023]
Abstract
BACKGROUND Brain-directed immunotherapy is a promising strategy to target amyloid-β (Aβ) deposits in Alzheimer's disease (AD). In the present study, we compared the therapeutic efficacy of the Aβ protofibril targeting antibody RmAb158 with its bispecific variant RmAb158-scFv8D3, which enters the brain by transferrin receptor-mediated transcytosis. METHODS AppNL-G-F knock-in mice received RmAb158, RmAb158-scFv8D3, or PBS in three treatment regimens. First, to assess the acute therapeutic effect, a single antibody dose was given to 5 months old AppNL-G-F mice, with evaluation after 3 days. Second, to assess the antibodies' ability to halt the progression of Aβ pathology, 3 months old AppNL-G-F mice received three doses during a week, with evaluation after 2 months. Reduction of RmAb158-scFv8D3 immunogenicity was explored by introducing mutations in the antibody or by depletion of CD4+ T cells. Third, to study the effects of chronic treatment, 7-month-old AppNL-G-F mice were CD4+ T cell depleted and treated with weekly antibody injections for 8 weeks, including a final diagnostic dose of [125I]RmAb158-scFv8D3, to determine its brain uptake ex vivo. Soluble Aβ aggregates and total Aβ42 were quantified with ELISA and immunostaining. RESULTS Neither RmAb158-scFv8D3 nor RmAb158 reduced soluble Aβ protofibrils or insoluble Aβ1-42 after a single injection treatment. After three successive injections, Aβ1-42 was reduced in mice treated with RmAb158, with a similar trend in RmAb158-scFv8D3-treated mice. Bispecific antibody immunogenicity was somewhat reduced by directed mutations, but CD4+ T cell depletion was used for long-term therapy. CD4+ T cell-depleted mice, chronically treated with RmAb158-scFv8D3, showed a dose-dependent increase in blood concentration of the diagnostic [125I]RmAb158-scFv8D3, while concentration was low in plasma and brain. Chronic treatment did not affect soluble Aβ aggregates, but a reduction in total Aβ42 was seen in the cortex of mice treated with both antibodies. CONCLUSIONS Both RmAb158 and its bispecific variant RmAb158-scFv8D3 achieved positive effects of long-term treatment. Despite its ability to efficiently enter the brain, the benefit of using the bispecific antibody in chronic treatment was limited by its reduced plasma exposure, which may be a result of interactions with TfR or the immune system. Future research will focus in new antibody formats to further improve Aβ immunotherapy.
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Affiliation(s)
- Tobias Gustavsson
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | | | - Elin Wik
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Sahar Roshanbin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Ulrika Julku
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | | | - Per Nilsson
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden
| | | | | | | | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden.
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11
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Bonvicini G, Syvänen S, Andersson KG, Haaparanta-Solin M, López-Picón F, Sehlin D. ImmunoPET imaging of amyloid-beta in a rat model of Alzheimer's disease with a bispecific, brain-penetrating fusion protein. Transl Neurodegener 2022; 11:55. [PMID: 36567338 PMCID: PMC9791759 DOI: 10.1186/s40035-022-00324-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 11/03/2022] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Hijacking the transferrin receptor (TfR) is an effective strategy to transport amyloid-beta (Aβ) immuno-positron emission tomography (immunoPET) ligands across the blood-brain barrier (BBB). Such ligands are more sensitive and specific than small-molecule ligands at detecting Aβ pathology in mouse models of Alzheimer's disease (AD). This study aimed to determine if this strategy would be as sensitive in rats and to assess how TfR affinity affects BBB transport of bispecific immunoPET radioligands. METHODS Two affinity variants of the rat TfR antibody, OX26, were chemically conjugated to a F(ab')2 fragment of the anti-Aβ antibody, bapineuzumab (Bapi), to generate two bispecific fusion proteins: OX265-F(ab')2-Bapi and OX2676-F(ab')2-Bapi. Pharmacokinetic analyses were performed 4 h and 70 h post-injection of radioiodinated fusion proteins in wild-type (WT) rats. [124I]I-OX265-F(ab')2-Bapi was administered to TgF344-AD and WT rats for in vivo PET imaging. Ex vivo distribution of injected [124I]I-OX265-F(ab')2-Bapi and Aβ pathology were assessed. RESULTS More [125I]I-OX265-F(ab')2-Bapi was taken up into the brain 4 h post-administration than [124I]I-OX2676-F(ab')2-Bapi. [124I]I-OX265-F(ab')2-Bapi PET visualized Aβ pathology with significantly higher signals in the TgF344-AD rats than in the WT littermates without Aβ pathology. The PET signals significantly correlated with Aβ levels in AD animals. CONCLUSION Affinity to TfR affects how efficiently a TfR-targeting bispecific fusion protein will cross the BBB, such that the higher-affinity bispecific fusion protein crossed the BBB more efficiently. Furthermore, bispecific immunoPET imaging of brain Aβ pathology using TfR-mediated transport provides good imaging contrast between TgF344-AD and WT rats, suggesting that this immunoPET strategy has the potential to be translated to higher species.
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Affiliation(s)
- Gillian Bonvicini
- grid.8993.b0000 0004 1936 9457Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden ,BioArctic AB, 112 51 Stockholm, Sweden
| | - Stina Syvänen
- grid.8993.b0000 0004 1936 9457Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden
| | | | - Merja Haaparanta-Solin
- grid.1374.10000 0001 2097 1371Preclinical Imaging Laboratory, Turku PET Centre, University of Turku, 20520 Turku, Finland ,grid.1374.10000 0001 2097 1371MediCity Research Laboratory, University of Turku, 20520 Turku, Finland
| | - Francisco López-Picón
- grid.1374.10000 0001 2097 1371Preclinical Imaging Laboratory, Turku PET Centre, University of Turku, 20520 Turku, Finland ,grid.1374.10000 0001 2097 1371MediCity Research Laboratory, University of Turku, 20520 Turku, Finland
| | - Dag Sehlin
- grid.8993.b0000 0004 1936 9457Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden
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12
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Julku U, Xiong M, Wik E, Roshanbin S, Sehlin D, Syvänen S. Brain pharmacokinetics of mono- and bispecific amyloid-β antibodies in wild-type and Alzheimer's disease mice measured by high cut-off microdialysis. Fluids Barriers CNS 2022; 19:99. [PMID: 36510227 PMCID: PMC9743601 DOI: 10.1186/s12987-022-00398-w] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 12/05/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Treatment with amyloid-β (Aβ) targeting antibodies is a promising approach to remove Aβ brain pathology in Alzheimer's disease (AD) and possibly even slow down or stop progression of the disease. One of the main challenges of brain immunotherapy is the restricted delivery of antibodies to the brain. However, bispecific antibodies that utilize the transferrin receptor (TfR) as a shuttle for transport across the blood-brain barrier (BBB) can access the brain better than traditional monospecific antibodies. Previous studies have shown that bispecific Aβ targeting antibodies have higher brain distribution, and can remove Aβ pathology more efficiently than monospecific antibodies. Yet, there is only limited information available on brain pharmacokinetics, especially regarding differences between mono- and bispecific antibodies. METHODS The aim of the study was to compare brain pharmacokinetics of Aβ-targeting monospecific mAb3D6 and its bispecific version mAb3D6-scFv8D3 that also targets TfR. High cut-off microdialysis was used to measure intravenously injected radiolabelled mAb3D6 and mAb3D6-scFv8D3 antibodies in the interstitial fluid (ISF) of hippocampus in wild-type mice and the AppNL-G-F mouse model of AD. Distribution of the antibodies in the brain and the peripheral tissue was examined by ex vivo autoradiography and biodistribution studies. RESULTS Brain concentrations of the bispecific antibody were elevated compared to the monospecific antibody in the hippocampal ISF measured by microdialysis and in the brain tissue at 4-6 h after an intravenous injection. The concentration of the bispecific antibody was approximately twofold higher in the ISF dialysate compared to the concentration of monospecific antibody and eightfold higher in brain tissue 6 h post-injection. The ISF dialysate concentrations for both antibodies were similar in both wild-type and AppNL-G-F mice 24 h post-injection, although the total brain tissue concentration of the bispecific antibody was higher than that of the monospecific antibody at this time point. Some accumulation of radioactivity around the probe area was observed especially for the monospecific antibody indicating that the probe compromised the BBB to some extent at the probe insertion site. CONCLUSION The BBB-penetrating bispecific antibody displayed higher ISF concentrations than the monospecific antibody. The concentration difference between the two antibodies was even larger in the whole brain than in the ISF. Further, the bispecific antibody, but not the monospecific antibody, displayed higher total brain concentrations than ISF concentrations, indicating association to brain tissue.
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Affiliation(s)
- Ulrika Julku
- grid.8993.b0000 0004 1936 9457Rudbeck Laboratory, Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjölds Väg 20, 751 85 Uppsala, Sweden
| | - Mengfei Xiong
- grid.8993.b0000 0004 1936 9457Rudbeck Laboratory, Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjölds Väg 20, 751 85 Uppsala, Sweden
| | - Elin Wik
- grid.8993.b0000 0004 1936 9457Rudbeck Laboratory, Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjölds Väg 20, 751 85 Uppsala, Sweden
| | - Sahar Roshanbin
- grid.8993.b0000 0004 1936 9457Rudbeck Laboratory, Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjölds Väg 20, 751 85 Uppsala, Sweden
| | - Dag Sehlin
- grid.8993.b0000 0004 1936 9457Rudbeck Laboratory, Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjölds Väg 20, 751 85 Uppsala, Sweden
| | - Stina Syvänen
- grid.8993.b0000 0004 1936 9457Rudbeck Laboratory, Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjölds Väg 20, 751 85 Uppsala, Sweden
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13
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Rofo F, Metzendorf NG, Saubi C, Suominen L, Godec A, Sehlin D, Syvänen S, Hultqvist G. Blood-brain barrier penetrating neprilysin degrades monomeric amyloid-beta in a mouse model of Alzheimer's disease. Alzheimers Res Ther 2022; 14:180. [PMID: 36471433 PMCID: PMC9720954 DOI: 10.1186/s13195-022-01132-2] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 11/25/2022] [Indexed: 12/12/2022]
Abstract
BACKGROUND Aggregation of the amyloid-β (Aβ) peptide in the brain is one of the key pathological events in Alzheimer's disease (AD). Reducing Aβ levels in the brain by enhancing its degradation is one possible strategy to develop new therapies for AD. Neprilysin (NEP) is a membrane-bound metallopeptidase and one of the major Aβ-degrading enzymes. The secreted soluble form of NEP (sNEP) has been previously suggested as a potential protein-therapy degrading Aβ in AD. However, similar to other large molecules, peripherally administered sNEP is unable to reach the brain due to the presence of the blood-brain barrier (BBB). METHODS To provide transcytosis across the BBB, we recombinantly fused the TfR binding moiety (scFv8D3) to either sNEP or a previously described variant of NEP (muNEP) suggested to have higher degradation efficiency of Aβ compared to other NEP substrates, but not per se to degrade Aβ more efficiently. To provide long blood half-life, an Fc-based antibody fragment (scFc) was added to the designs, forming sNEP-scFc-scFv8D3 and muNEP-scFc-scFv8D3. The ability of the mentioned recombinant proteins to degrade Aβ was first evaluated in vitro using synthetic Aβ peptides followed by sandwich ELISA. For the in vivo studies, a single injection of 125-iodine-labelled sNEP-scFc-scFv8D3 and muNEP-scFc-scFv8D3 was intravenously administered to a tg-ArcSwe mouse model of AD, using scFc-scFv8D3 protein that lacks NEP as a negative control. Different ELISA setups were applied to quantify Aβ concentration of different conformations, both in brain tissues and blood samples. RESULTS When tested in vitro, sNEP-scFc-scFv8D3 retained sNEP enzymatic activity in degrading Aβ and both constructs efficiently degraded arctic Aβ. When intravenously injected, sNEP-scFc-scFv8D3 demonstrated 20 times higher brain uptake compared to sNEP. Both scFv8D3-fused NEP proteins significantly reduced aggregated Aβ levels in the blood of tg-ArcSwe mice, a transgenic mouse model of AD, following a single intravenous injection. In the brain, monomeric and oligomeric Aβ were significantly reduced. Both scFv8D3-fused NEP proteins displayed a fast clearance from the brain. CONCLUSION A one-time injection of a BBB-penetrating NEP shows the potential to reduce, the likely most toxic, Aβ oligomers in the brain in addition to monomers. Also, Aβ aggregates in the blood were reduced.
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Affiliation(s)
- Fadi Rofo
- grid.8993.b0000 0004 1936 9457Department of Pharmacy, Uppsala University, Biomedicinskt Centrum BMC, Husargatan 3, 751 24 Uppsala, Sweden
| | - Nicole G. Metzendorf
- grid.8993.b0000 0004 1936 9457Department of Pharmacy, Uppsala University, Biomedicinskt Centrum BMC, Husargatan 3, 751 24 Uppsala, Sweden
| | - Cristina Saubi
- grid.8993.b0000 0004 1936 9457Department of Pharmacy, Uppsala University, Biomedicinskt Centrum BMC, Husargatan 3, 751 24 Uppsala, Sweden
| | - Laura Suominen
- grid.8993.b0000 0004 1936 9457Department of Pharmacy, Uppsala University, Biomedicinskt Centrum BMC, Husargatan 3, 751 24 Uppsala, Sweden
| | - Ana Godec
- grid.8993.b0000 0004 1936 9457Department of Pharmacy, Uppsala University, Biomedicinskt Centrum BMC, Husargatan 3, 751 24 Uppsala, Sweden
| | - Dag Sehlin
- grid.8993.b0000 0004 1936 9457Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- grid.8993.b0000 0004 1936 9457Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Greta Hultqvist
- grid.8993.b0000 0004 1936 9457Department of Pharmacy, Uppsala University, Biomedicinskt Centrum BMC, Husargatan 3, 751 24 Uppsala, Sweden
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14
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Radjani Bidesi NS, Battisti UM, Lopes van de Broek S, Shalgunov V, Dall AM, Bøggild Kristensen J, Sehlin D, Syvänen S, Moos Knudsen G, Herth MM. Development of the First Tritiated Tetrazine: Facilitating Tritiation of Proteins. Chembiochem 2022; 23:e202200539. [PMID: 36333105 PMCID: PMC10100488 DOI: 10.1002/cbic.202200539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 09/15/2022] [Revised: 10/10/2022] [Indexed: 11/06/2022]
Abstract
Tetrazine (Tz)-trans-cyclooctene (TCO) ligation is an ultra-fast and highly selective reaction and it is particularly suited to label biomolecules under physiological conditions. As such, a 3 H-Tz based synthon would have wide applications for in vitro/ex vivo assays. In this study, we developed a 3 H-labeled Tz and characterized its potential for application to pretargeted autoradiography. Several strategies were explored to synthesize such a Tz. However, classical approaches such as reductive halogenation failed. For this reason, we designed a Tz containing an aldehyde and explored the possibility of reducing this group with NaBT4 . This approach was successful and resulted in [3 H]-(4-(6-(pyridin-2-yl)-1,2,4,5-tetrazin-3-yl)phenyl)methan-t-ol with a radiochemical yield of 22 %, a radiochemical purity of 96 % and a molar activity of 0.437 GBq/μmol (11.8 Ci/mmol). The compound was successfully applied to pretargeted autoradiography. Thus, we report the synthesis of the first 3 H-labeled Tz and its successful application as a labeling building block.
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Affiliation(s)
- Natasha Shalina Radjani Bidesi
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - Umberto Maria Battisti
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - Sara Lopes van de Broek
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark
| | - Vladimir Shalgunov
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark.,Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Anne-Mette Dall
- Novo Nordisk A/S, Smørmosevej 17-19, Bagsvaerd, 2880, Copenhagen, Denmark
| | | | - Dag Sehlin
- Rudbeck Laboratory, Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjölds väg 20, 75185, Uppsala, Sweden
| | - Stina Syvänen
- Rudbeck Laboratory, Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjölds väg 20, 75185, Uppsala, Sweden
| | - Gitte Moos Knudsen
- Neurobiology Research Unit, Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Matthias Manfred Herth
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100, Copenhagen, Denmark.,Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen, Denmark
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15
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Meier SR, Sehlin D, Syvänen S. Passive and receptor mediated brain delivery of an anti-GFAP nanobody. Nucl Med Biol 2022; 114-115:121-127. [PMID: 35487832 DOI: 10.1016/j.nucmedbio.2022.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [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: 12/22/2021] [Revised: 03/24/2022] [Accepted: 04/04/2022] [Indexed: 12/27/2022]
Abstract
PURPOSE Antibody-based constructs, engineered to enter the brain using transferrin receptor (TfR) mediated transcytosis, have been successfully used as PET radioligands for imaging of amyloid-beta (Aβ) in preclinical studies. However, these radioligands have been large and associated with long circulation times, i.e. non-optimal properties for neuroPET radioligands. The aim of this study was to investigate the in vivo brain delivery of the radiolabeled nanobody VHH-E9 that binds to glial fibrillary acidic protein (GFAP) expressed by reactive astrocytes, without and with fusion to a TfR binding moiety, as potential tools to detect neuroinflammation. METHODS Three protein constructs were recombinantly expressed: 1) The GFAP specific nanobody VHH-E9, 2) VHH-E9 fused to a single chain variable fragment of the TfR binding antibody 8D3 (scFv8D3) and 3) scFv8D3 alone. Brain delivery of the constructs was investigated at 2 h post injection. Binding to GFAP was studied with autoradiography while in vivo brain retention of [125I]VHH-E9 and [125I]VHH-E9-scFv8D3 was further investigated at 8 h, 24 h and 48 h in wild-type (WT), and at the same time points in transgenic mice (ArcSwe) that in addition to Aβ pathology also display neuroinflammation. RESULTS At 2 h after administration, [125I]VHH-E9-scFv8D3 and [125I]scFv8D3 displayed 3-fold higher brain concentrations than [125I]VHH-E9. In vitro autoradiography showed distinct binding of both [125I]VHH-E9-scFv8D3 and [125I]VHH-E9 to regions with abundant GFAP in ArcSwe mice. However, in vivo, there was no difference in brain concentrations between WT and ArcSwe at any of the studied time points. CONCLUSIONS Fused to scFv8D3, VHH-E9 displayed increased brain delivery. When radiolabeled and applied on brain sections, the bispecific construct was able to discriminate between WT and ArcSwe mice, but in vivo brain uptake and retention over time did not differ between WT and ArcSwe mice.
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Affiliation(s)
- Silvio R Meier
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden.
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16
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Schlein E, Syvänen S, Rokka J, Gustavsson T, Rossin R, Robillard M, Eriksson J, Sehlin D. Functionalization of Radiolabeled Antibodies to Enhance Peripheral Clearance for High Contrast Brain Imaging. Mol Pharm 2022; 19:4111-4122. [PMID: 36201682 PMCID: PMC9644377 DOI: 10.1021/acs.molpharmaceut.2c00536] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Small molecule imaging
agents such as [11C]PiB, which
bind to the core of insoluble amyloid-β (Aβ) fibrils,
are useful tools in Alzheimer’s disease (AD) research, diagnostics,
and drug development. However, the [11C]PiB PET signal
saturates early in the disease progression and does not detect soluble
or diffuse Aβ pathology which are believed to play important
roles in the disease progression. Antibodies, modified into a bispecific
format to enter the brain via receptor-mediated transcytosis, could
be a suitable alternative because of their diversity and high specificity
for their target. However, the circulation time of these antibodies
is long, resulting in an extended exposure to radiation and low imaging
contrast. Here, we explore two alternative strategies to enhance imaging
contrast by increasing clearance of the antibody ligand from blood.
The bispecific Aβ targeting antibody RmAb158-scFv8D3 and the
monospecific RmAb158 were radiolabeled and functionalized with either
α-d-mannopyranosylphenyl isothiocyanate (mannose) or
with trans-cyclooctene (TCO). While mannose can directly
mediate antibody clearance via the liver, TCO-modified antibody clearance
was induced by injection of a tetrazine-functionalized, liver-targeting
clearing agent (CA). In vivo experiments in wild type and AD transgenic
mice demonstrated the ability of both strategies to drastically shorten
the circulation time of RmAb158, while they had limited effect on
the bispecific variant RmAb158-8D3. Furthermore, single photon emission
computed tomography imaging with TCO-[125I]I-RmAb158 in
AD mice showed higher contrast 1 day after injection of the tetrazine-functionalized
CA. In conclusion, strategies to enhance the clearance of antibody-based
imaging ligands could allow imaging at earlier time points and thereby
open the possibility to combine antibodies with short-lived radionuclides
such as fluorine-18.
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Affiliation(s)
- Eva Schlein
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden
| | - Johanna Rokka
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden
| | - Tobias Gustavsson
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden
| | - Raffaella Rossin
- Tagworks Pharmaceuticals, Toernooiveld 1, 6525 ED Nijmegen, Netherlands
| | - Marc Robillard
- Tagworks Pharmaceuticals, Toernooiveld 1, 6525 ED Nijmegen, Netherlands
| | - Jonas Eriksson
- PET Centre, Uppsala University Hospital, 751 85 Uppsala, Sweden.,Department of Medicinal Chemistry, Uppsala University, 751 23 Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden
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17
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Lopes van den Broek S, Shalgunov V, García Vázquez R, Beschorner N, Bidesi NSR, Nedergaard M, Knudsen GM, Sehlin D, Syvänen S, Herth MM. Pretargeted Imaging beyond the Blood–Brain Barrier—Utopia or Feasible? Pharmaceuticals (Basel) 2022; 15:ph15101191. [PMID: 36297303 PMCID: PMC9612205 DOI: 10.3390/ph15101191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 11/17/2022] Open
Abstract
Pretargeting is a promising nuclear imaging technique that allows for the usage of antibodies (Abs) with enhanced imaging contrast and reduced patient radiation burden. It is based on bioorthogonal chemistry with the tetrazine ligation—a reaction between trans-cyclooctenes (TCOs) and tetrazines (Tzs)—currently being the most popular reaction due to its high selectivity and reactivity. As Abs can be designed to bind specifically to currently ‘undruggable’ targets such as protein isoforms or oligomers, which play a crucial role in neurodegenerative diseases, pretargeted imaging beyond the BBB is highly sought after, but has not been achieved yet. A challenge in this respect is that large molecules such as Abs show poor brain uptake. Uptake can be increased by receptor mediated transcytosis; however, it is largely unknown if the achieved brain concentrations are sufficient for pretargeted imaging. In this study, we investigated whether the required concentrations are feasible to reach. As a model Ab, we used the bispecific anti-amyloid beta (Aβ) anti-transferrin receptor (TfR) Ab 3D6scFv8D3 and conjugated it to a different amount of TCOs per Ab and tested different concentrations in vitro. With this model in hand, we estimated the minimum required TCO concentration to achieve a suitable contrast between the high and low binding regions. The estimation was carried out using pretargeted autoradiography on brain sections of an Alzheimer’s disease mouse model. Biodistribution studies in wild-type (WT) mice were used to correlate how different TCO/Ab ratios alter the brain uptake. Pretargeted autoradiography showed that increasing the number of TCOs as well as increasing the TCO-Ab concentration increased the imaging contrast. A minimum brain concentration of TCOs for pretargeting purposes was determined to be 10.7 pmol/g in vitro. Biodistribution studies in WT mice showed a brain uptake of 1.1% ID/g using TCO-3D6scFv8D3 with 6.8 TCO/Ab. According to our estimations using the optimal parameters, pretargeted imaging beyond the BBB is not a utopia. Necessary brain TCO concentrations can be reached and are in the same order of magnitude as required to achieve sufficient contrast. This work gives a first estimate that pretargeted imaging is indeed possible with antibodies. This could allow the imaging of currently ‘undruggable’ targets and therefore be crucial to monitor (e.g., therapies for intractable neurodegenerative diseases).
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Affiliation(s)
- Sara Lopes van den Broek
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Vladimir Shalgunov
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Rocío García Vázquez
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Natalie Beschorner
- Center for Translational Neuromedicine, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Natasha S. R. Bidesi
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Gitte M. Knudsen
- Neurobiology Research Unit, Rigshospitalet Copenhagen University Hospital, Blegdamsvej 9, 2100 Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Dag Sehlin
- Rudbeck Laboratory, Department of Public Health and Caring Sciences, University of Uppsala, Dag Hammarskjölds väg 20, 75185 Uppsala, Sweden
| | - Stina Syvänen
- Rudbeck Laboratory, Department of Public Health and Caring Sciences, University of Uppsala, Dag Hammarskjölds väg 20, 75185 Uppsala, Sweden
| | - Matthias M. Herth
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet Copenhagen University Hospital, Blegdamsvej 9, 2100 Copenhagen, Denmark
- Correspondence:
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18
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Rofo F, Meier SR, Metzendorf NG, Morrison JI, Petrovic A, Syvänen S, Sehlin D, Hultqvist G. A Brain-Targeting Bispecific-Multivalent Antibody Clears Soluble Amyloid-Beta Aggregates in Alzheimer's Disease Mice. Neurotherapeutics 2022; 19:1588-1602. [PMID: 35939261 PMCID: PMC9606191 DOI: 10.1007/s13311-022-01283-y] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/20/2022] [Indexed: 12/04/2022] Open
Abstract
Amyloid-β (Aβ) oligomers and protofibrils are suggested to be the most neurotoxic Aβ species in Alzheimer's disease (AD). Hence, antibodies with strong and selective binding to these soluble Aβ aggregates are of therapeutic potential. We have recently introduced HexaRmAb158, a multivalent antibody with additional Aβ-binding sites in the form of single-chain fragment variables (scFv) on the N-terminal ends of Aβ protofibril selective antibody (RmAb158). Due to the additional binding sites and the short distance between them, HexaRmAb158 displayed a slow dissociation from protofibrils and strong binding to oligomers in vitro. In the current study, we aimed at investigating the therapeutic potential of this antibody format in vivo using mouse models of AD. To enhance BBB delivery, the transferrin receptor (TfR) binding moiety (scFv8D3) was added, forming the bispecific-multivalent antibody (HexaRmAb158-scFv8D3). The new antibody displayed a weaker TfR binding compared to the previously developed RmAb158-scFv8D3 and was less efficiently transcytosed in a cell-based BBB model. HexaRmAb158 detected soluble Aβ aggregates derived from brains of tg-ArcSwe and AppNL-G-F mice more efficiently compared to RmAb158. When intravenously injected, HexaRmAb158-scFv8D3 was actively transported over the BBB into the brain in vivo. Brain uptake was marginally lower than that of RmAb158-scFv8D3, but significantly higher than observed for conventional IgG antibodies. Both antibody formats displayed similar brain retention (72 h post injection) and equal capacity in clearing soluble Aβ aggregates in tg-ArcSwe mice. In conclusion, we demonstrate a bispecific-multivalent antibody format capable of passing the BBB and targeting a wide-range of sizes of soluble Aβ aggregates.
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Affiliation(s)
- Fadi Rofo
- Department of Pharmacy, Uppsala University, 75124, Uppsala, Sweden
| | - Silvio R Meier
- Department of Public Health and Caring Sciences, Uppsala University, 75185, Uppsala, Sweden
| | | | - Jamie I Morrison
- Department of Pharmacy, Uppsala University, 75124, Uppsala, Sweden
| | - Alex Petrovic
- Department of Pharmacy, Uppsala University, 75124, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, 75185, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, 75185, Uppsala, Sweden
| | - Greta Hultqvist
- Department of Pharmacy, Uppsala University, 75124, Uppsala, Sweden.
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19
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Roshanbin S, Julku U, Xiong M, Eriksson J, Masliah E, Hultqvist G, Bergström J, Ingelsson M, Syvänen S, Sehlin D. Reduction of αSYN Pathology in a Mouse Model of PD Using a Brain-Penetrating Bispecific Antibody. Pharmaceutics 2022; 14:pharmaceutics14071412. [PMID: 35890306 PMCID: PMC9318263 DOI: 10.3390/pharmaceutics14071412] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 06/28/2022] [Accepted: 07/01/2022] [Indexed: 02/04/2023] Open
Abstract
Immunotherapy targeting aggregated alpha-synuclein (αSYN) is a promising approach for the treatment of Parkinson’s disease. However, brain penetration of antibodies is hampered by their large size. Here, RmAbSynO2-scFv8D3, a modified bispecific antibody that targets aggregated αSYN and binds to the transferrin receptor for facilitated brain uptake, was investigated to treat αSYN pathology in transgenic mice. Ex vivo analyses of the blood and brain distribution of RmAbSynO2-scFv8D3 and the unmodified variant RmAbSynO2, as well as in vivo analyses with microdialysis and PET, confirmed fast and efficient brain uptake of the bispecific format. In addition, intravenous administration was shown to be superior to intraperitoneal injections in terms of brain uptake and distribution. Next, aged female αSYN transgenic mice (L61) were administered either RmAbSynO2-scFv8D3, RmAbSynO2, or PBS intravenously three times over five days. Levels of TBS-T soluble aggregated αSYN in the brain following treatment with RmAbSynO2-scFv8D3 were decreased in the cortex and midbrain compared to RmAbSynO2 or PBS controls. Taken together, our results indicate that facilitated brain uptake of αSYN antibodies can improve treatment of αSYN pathology.
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Affiliation(s)
- Sahar Roshanbin
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden; (U.J.); (M.X.); (J.B.); (M.I.); (S.S.)
- Correspondence: (S.R.); (D.S.)
| | - Ulrika Julku
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden; (U.J.); (M.X.); (J.B.); (M.I.); (S.S.)
| | - Mengfei Xiong
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden; (U.J.); (M.X.); (J.B.); (M.I.); (S.S.)
| | - Jonas Eriksson
- Department of Medicinal Chemistry, Uppsala University, 751 23 Uppsala, Sweden;
- PET Centre, Uppsala University Hospital, 751 85 Uppsala, Sweden
| | - Eliezer Masliah
- Division of Neuroscience and Laboratory of Neurogenetics, NIA-NIH, Bethesda, MD 20814, USA;
| | - Greta Hultqvist
- Department of Pharmacy, Uppsala University, 752 37 Uppsala, Sweden;
| | - Joakim Bergström
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden; (U.J.); (M.X.); (J.B.); (M.I.); (S.S.)
| | - Martin Ingelsson
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden; (U.J.); (M.X.); (J.B.); (M.I.); (S.S.)
- Krembil Brain Institute, University Health Network, Toronto, ON M5T 1M8, Canada
- Department of Medicine and Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON M5T 1M8, Canada
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden; (U.J.); (M.X.); (J.B.); (M.I.); (S.S.)
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden; (U.J.); (M.X.); (J.B.); (M.I.); (S.S.)
- Correspondence: (S.R.); (D.S.)
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20
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Syvänen S, Meier SR, Roshanbin S, Xiong M, Faresjö R, Gustavsson T, Bonvicini G, Schlein E, Aguilar X, Julku U, Eriksson J, Sehlin D. PET Imaging in Preclinical Anti-Aβ Drug Development. Pharm Res 2022; 39:1481-1496. [PMID: 35501533 PMCID: PMC9246809 DOI: 10.1007/s11095-022-03277-z] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 04/25/2022] [Indexed: 11/21/2022]
Abstract
Positron emission tomography (PET), a medical imaging technique allowing for studies of the living human brain, has gained an important role in clinical trials of novel drugs against Alzheimer’s disease (AD). For example, PET data contributed to the conditional approval in 2021 of aducanumab, an antibody directed towards amyloid-beta (Aβ) aggregates, by showing a dose-dependent reduction in brain amyloid after treatment. In parallel to clinical studies, preclinical studies in animal models of Aβ pathology may also benefit from PET as a tool to detect target engagement and treatment effects of anti-Aβ drug candidates. PET is associated with a high level of translatability between species as similar, non-invasive protocols allow for longitudinal rather than cross-sectional studies and can be used both in a preclinical and clinical setting. This review focuses on the use of preclinical PET imaging in genetically modified animals that express human Aβ, and its present and potential future role in the development of drugs aimed at reducing brain Aβ levels as a therapeutic strategy to halt disease progression in AD.
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Affiliation(s)
- Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden.
| | - Silvio R Meier
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden
| | - Sahar Roshanbin
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden
| | - Mengfei Xiong
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden
| | - Rebecca Faresjö
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden
| | - Tobias Gustavsson
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden
| | - Gillian Bonvicini
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden.,BioArctic AB, Stockholm, Sweden
| | - Eva Schlein
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden
| | - Ximena Aguilar
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden
| | - Ulrika Julku
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden
| | - Jonas Eriksson
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden.,PET Centre, Uppsala University Hospital, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Dag Hammarskjöldsväg 20, 75185, Uppsala, Sweden
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21
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van den Broek SL, Shalgunov V, Knudsen G, Sehlin D, Syvaenen S, Herth M. Trans-cyclooctene modified antibodies for pretargeted imaging of amyloid-β. Nucl Med Biol 2022. [DOI: 10.1016/s0969-8051(22)00226-8] [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: 11/24/2022]
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22
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Bidesi N, Battisti U, van den Broek SL, Shalgunov V, Dall AM, Kristensen J, Sehlin D, Syvaenen S, Knudsen G, Herth M. A convenient tritiation strategy for tetrazines. Nucl Med Biol 2022. [DOI: 10.1016/s0969-8051(22)00211-6] [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: 11/26/2022]
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23
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Roshanbin S, Xiong M, Hultqvist G, Söderberg L, Zachrisson O, Meier S, Ekmark-Lewén S, Bergström J, Ingelsson M, Sehlin D, Syvänen S. In vivo imaging of alpha-synuclein with antibody-based PET. Neuropharmacology 2022; 208:108985. [PMID: 35149134 DOI: 10.1016/j.neuropharm.2022.108985] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [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: 07/04/2021] [Revised: 01/05/2022] [Accepted: 02/02/2022] [Indexed: 12/11/2022]
Abstract
The protein alpha-synuclein (αSYN) plays a central role in synucleinopathies such as Parkinsons's disease (PD) and multiple system atrophy (MSA). Presently, there are no selective αSYN positron emission tomography (PET) radioligands that do not also show affinity to amyloid-beta (Aβ). We have previously shown that radiolabeled antibodies, engineered to enter the brain via the transferrin receptor (TfR), is a promising approach for PET imaging of intrabrain targets. In this study, we used this strategy to visualize αSYN in the living mouse brain. Five bispecific antibodies, binding to both the murine TfR and αSYN were generated and radiolabeled with iodine-125 or iodine-124. All bispecific antibodies bound to αSYN and mTfR before and after radiolabelling in an ELISA assay, and bound to brain sections prepared from αSYN overexpressing mice as well as human PD- and MSA subjects, but not control tissues in autoradiography. Brain concentrations of the bispecific antibodies were between 26-63 times higher than the unmodified IgG format 2 h post-injection, corresponding to about 1.5% of the injected dose per gram brain tissue. Additionally, intrastriatal αSYN fibrils were visualised with PET in an αSYN deposition mouse model with one of the bispecific antibodies, [124I]RmAbSynO2-scFv8D3. However, PET images acquired in αSYN transgenic mice with verified brain pathology injected with [124I]RmAbSynO2-scFv8D3 and [124I]RmAb48-scFv8D3 showed no increase in antibody retention compared to WT mice. Despite successful imaging of deposited extracellular αSYN using a brain-penetrating antibody-based radioligand with no cross-specificity towards Aβ, this proof-of-concept study demonstrates challenges in imaging intracellular αSYN inclusions present in synucleinopathies.
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Affiliation(s)
- Sahar Roshanbin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden.
| | - Mengfei Xiong
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Greta Hultqvist
- Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | | | | | - Silvio Meier
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Sara Ekmark-Lewén
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Joakim Bergström
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Martin Ingelsson
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden; Department of Medicine and Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Canada
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
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24
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Rofo F, Buijs J, Falk R, Honek K, Lannfelt L, Lilja AM, Metzendorf NG, Gustavsson T, Sehlin D, Söderberg L, Hultqvist G. Novel multivalent design of a monoclonal antibody improves binding strength to soluble aggregates of amyloid beta. Transl Neurodegener 2021; 10:38. [PMID: 34579778 PMCID: PMC8477473 DOI: 10.1186/s40035-021-00258-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 03/17/2021] [Accepted: 08/14/2021] [Indexed: 11/30/2022] Open
Abstract
Background Amyloid-β (Aβ) immunotherapy is a promising therapeutic strategy in the fight against Alzheimer’s disease (AD). A number of monoclonal antibodies have entered clinical trials for AD. Some of them have failed due to the lack of efficacy or side-effects, two antibodies are currently in phase 3, and one has been approved by FDA. The soluble intermediate aggregated species of Aβ, termed oligomers and protofibrils, are believed to be key pathogenic forms, responsible for synaptic and neuronal degeneration in AD. Therefore, antibodies that can strongly and selectively bind to these soluble intermediate aggregates are of great diagnostic and therapeutic interest. Methods We designed and recombinantly produced a hexavalent antibody based on mAb158, an Aβ protofibril-selective antibody. The humanized version of mAb158, lecanemab (BAN2401), is currently in phase 3 clinical trials for the treatment of AD. The new designs involved recombinantly fusing single-chain fragment variables to the N-terminal ends of mAb158 antibody. Real-time interaction analysis with LigandTracer and surface plasmon resonance were used to evaluate the kinetic binding properties of the generated antibodies to Aβ protofibrils. Different ELISA setups were applied to demonstrate the binding strength of the hexavalent antibody to Aβ aggregates of different sizes. Finally, the ability of the antibodies to protect cells from Aβ-induced effects was evaluated by MTT assay. Results Using real-time interaction analysis with LigandTracer, the hexavalent design promoted a 40-times enhanced binding with avidity to protofibrils, and most of the added binding strength was attributed to the reduced rate of dissociation. Furthermore, ELISA experiments demonstrated that the hexavalent design also had strong binding to small oligomers, while retaining weak and intermediate binding to monomers and insoluble fibrils. The hexavalent antibody also reduced cell death induced by a mixture of soluble Aβ aggregates. Conclusion We provide a new antibody design with increased valency to promote binding avidity to an enhanced range of sizes of Aβ aggregates. This approach should be general and work for any aggregated protein or repetitive target. Supplementary Information The online version contains supplementary material available at 10.1186/s40035-021-00258-x.
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Affiliation(s)
- Fadi Rofo
- Protein Drug Design, Faculty of Pharmacy, Uppsala University, 75124, Uppsala, Sweden
| | - Jos Buijs
- Department of Immunology, Genetics and Pathology, Uppsala University, 75185, Uppsala, Sweden.,Ridgeview Instruments, 75237, Uppsala, Sweden
| | | | - Ken Honek
- BioArctic AB, 11251, Stockholm, Sweden
| | - Lars Lannfelt
- BioArctic AB, 11251, Stockholm, Sweden.,Department of Public Health and Caring Sciences, Uppsala University, 75185, Uppsala, Sweden
| | | | - Nicole G Metzendorf
- Protein Drug Design, Faculty of Pharmacy, Uppsala University, 75124, Uppsala, Sweden
| | - Tobias Gustavsson
- Department of Public Health and Caring Sciences, Uppsala University, 75185, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, 75185, Uppsala, Sweden
| | | | - Greta Hultqvist
- Protein Drug Design, Faculty of Pharmacy, Uppsala University, 75124, Uppsala, Sweden.
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25
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Pagnon de la Vega M, Giedraitis V, Michno W, Kilander L, Güner G, Zielinski M, Löwenmark M, Brundin R, Danfors T, Söderberg L, Alafuzoff I, Nilsson LNG, Erlandsson A, Willbold D, Müller SA, Schröder GF, Hanrieder J, Lichtenthaler SF, Lannfelt L, Sehlin D, Ingelsson M. The Uppsala APP deletion causes early onset autosomal dominant Alzheimer's disease by altering APP processing and increasing amyloid β fibril formation. Sci Transl Med 2021; 13:13/606/eabc6184. [PMID: 34380771 DOI: 10.1126/scitranslmed.abc6184] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 02/05/2021] [Accepted: 06/22/2021] [Indexed: 12/23/2022]
Abstract
Point mutations in the amyloid precursor protein gene (APP) cause familial Alzheimer's disease (AD) by increasing generation or altering conformation of amyloid β (Aβ). Here, we describe the Uppsala APP mutation (Δ690-695), the first reported deletion causing autosomal dominant AD. Affected individuals have an age at symptom onset in their early forties and suffer from a rapidly progressing disease course. Symptoms and biomarkers are typical of AD, with the exception of normal cerebrospinal fluid (CSF) Aβ42 and only slightly pathological amyloid-positron emission tomography signals. Mass spectrometry and Western blot analyses of patient CSF and media from experimental cell cultures indicate that the Uppsala APP mutation alters APP processing by increasing β-secretase cleavage and affecting α-secretase cleavage. Furthermore, in vitro aggregation studies and analyses of patient brain tissue samples indicate that the longer form of mutated Aβ, AβUpp1-42Δ19-24, accelerates the formation of fibrils with unique polymorphs and their deposition into amyloid plaques in the affected brain.
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Affiliation(s)
- María Pagnon de la Vega
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, 75185 Uppsala, Sweden
| | - Vilmantas Giedraitis
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, 75185 Uppsala, Sweden
| | - Wojciech Michno
- Department of Psychiatry and Neurochemistry, University of Gothenburg, 43180 Gothenburg, Sweden.,Department of Neuroscience, Physiology and Pharmacology, University College London, WC1E 6BT London, UK
| | - Lena Kilander
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, 75185 Uppsala, Sweden
| | - Gökhan Güner
- German Center for Neurodegenerative Diseases (DZNE) and Neuroproteomics, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81377 Munich, Germany
| | - Mara Zielinski
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7) and JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Malin Löwenmark
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, 75185 Uppsala, Sweden
| | - RoseMarie Brundin
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, 75185 Uppsala, Sweden
| | - Torsten Danfors
- Department of Surgical Sciences, Radiology, Uppsala University, 75185 Uppsala, Sweden
| | | | - Irina Alafuzoff
- Department of Immunology, Genetics and Pathology, Clinical and Experimental Pathology, Uppsala University, 75185 Uppsala, Sweden
| | - Lars N G Nilsson
- Department of Pharmacology, University of Oslo and Oslo University Hospital, 0316 Oslo, Norway
| | - Anna Erlandsson
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, 75185 Uppsala, Sweden
| | - Dieter Willbold
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7) and JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany.,Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.,Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, State University, 141701 Dolgoprudny, Russia
| | - Stephan A Müller
- German Center for Neurodegenerative Diseases (DZNE) and Neuroproteomics, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81377 Munich, Germany
| | - Gunnar F Schröder
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7) and JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany.,Physics Department, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Jörg Hanrieder
- Department of Psychiatry and Neurochemistry, University of Gothenburg, 43180 Gothenburg, Sweden.,Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, WC1N 3BG London, UK
| | - Stefan F Lichtenthaler
- German Center for Neurodegenerative Diseases (DZNE) and Neuroproteomics, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81377 Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, 75185 Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, 75185 Uppsala, Sweden
| | - Martin Ingelsson
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, 75185 Uppsala, Sweden.
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Xiong M, Roshanbin S, Rokka J, Schlein E, Ingelsson M, Sehlin D, Eriksson J, Syvänen S. In vivo imaging of synaptic density with [ 11C]UCB-J PET in two mouse models of neurodegenerative disease. Neuroimage 2021; 239:118302. [PMID: 34174391 DOI: 10.1016/j.neuroimage.2021.118302] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [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: 02/23/2021] [Revised: 06/15/2021] [Accepted: 06/22/2021] [Indexed: 12/16/2022] Open
Abstract
The positron emission tomography (PET) radioligand [11C]UCB-J binds to synaptic vesicle protein 2A (SV2A) and is used to investigate synaptic density in the living brain. Clinical studies have indicated reduced [11C]UCB-J binding in Alzheimer's disease (AD) and Parkinson's disease (PD) brains compared to healthy controls. Still, it is unknown whether [11C]UCB-J PET can visualise synaptic loss in mouse models of these disorders. Such models are essential for understanding disease pathology and for evaluating the effects of novel disease-modifying drug candidates. In the present study, synaptic density in transgenic models of AD (ArcSwe) and PD (L61) was studied using [11C]UCB-J PET. Data were acquired during 60 min after injection, and time-activity curves (TACs) in different brain regions and the left ventricle of the heart were generated based on the dynamic PET images. The [11C]UCB-J brain concentrations were expressed as standardised uptake value (SUV) over time. The area under the SUV curve (AUC), the ratio of AUC in the brain to that in the heart (AUCbrain/blood), and the volume of distribution (VT) obtained by kinetic modelling using the heart TAC as input were compared between transgenic and age-matched wild type (WT) mice. The L61 mice displayed 11-13% lower AUCbrain/blood ratio and brain VT generated by kinetic modeling compared to the control WT mice. In general, also transgenic ArcSwe mice tended to show lower [11C]UCB-J brain exposure than age-matched WT controls, but variation within the different animal groups was high. Older WT mice (18-20 months) showed lower [11C]UCB-J brain exposure than younger WT mice (8-9 months). Together, these data imply that [11C]UCB-J PET reflects synaptic density in mouse models of neurodegeneration and that inter-subject variation is large. In addition, the study suggested that model-independent AUCbrain/blood ratio can be used to evaluate [11C]UCB-J binding as an alternative to full pharmacokinetic modelling.
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Affiliation(s)
- Mengfei Xiong
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, Uppsala SE-751 85, Sweden
| | - Sahar Roshanbin
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, Uppsala SE-751 85, Sweden
| | - Johanna Rokka
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, Uppsala SE-751 85, Sweden
| | - Eva Schlein
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, Uppsala SE-751 85, Sweden
| | - Martin Ingelsson
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, Uppsala SE-751 85, Sweden
| | - Dag Sehlin
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, Uppsala SE-751 85, Sweden
| | - Jonas Eriksson
- Department of Medicinal Chemistry, Uppsala University, Uppsala SE-751 23, Sweden; PET Centre, Uppsala University Hospital, Uppsala SE-751 85, Sweden
| | - Stina Syvänen
- Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, Uppsala SE-751 85, Sweden.
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Meier SR, Sehlin D, Roshanbin S, Lim Falk V, Saito T, Saido TC, Neumann U, Rokka J, Eriksson J, Syvanen S. 11C-PIB and 124I-antibody PET provide differing estimates of brain amyloid-beta after therapeutic intervention. J Nucl Med 2021; 63:302-309. [PMID: 34088777 PMCID: PMC8805773 DOI: 10.2967/jnumed.121.262083] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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: 02/07/2021] [Revised: 05/05/2021] [Indexed: 11/16/2022] Open
Abstract
PET imaging of amyloid-β (Aβ) has become an important component of Alzheimer disease diagnosis. 11C-Pittsburgh compound B (11C-PiB) and analogs bind to fibrillar Aβ. However, levels of nonfibrillar, soluble, aggregates of Aβ appear more dynamic during disease progression and more affected by Aβ-reducing treatments. The aim of this study was to compare an antibody-based PET ligand targeting nonfibrillar Aβ with 11C-PiB after β-secretase (BACE-1) inhibition in 2 Alzheimer disease mouse models at an advanced stage of Aβ pathology. Methods: Transgenic ArcSwe mice (16 mo old) were treated with the BACE-1 inhibitor NB-360 for 2 mo, whereas another group was kept as controls. A third group was analyzed at the age of 16 mo as a baseline. Mice were PET-scanned with 11C-PiB to measure Aβ plaque load followed by a scan with the bispecific radioligand 124I-RmAb158-scFv8D3 to investigate nonfibrillar aggregates of Aβ. The same study design was then applied to another mouse model, AppNL-G-F. In this case, NB-360 treatment was initiated at the age of 8 mo and animals were scanned with 11C-PiB-PET and 125I-RmAb158-scFv8D3 SPECT. Brain tissue was isolated after scanning, and Aβ levels were assessed. Results:124I-RmAb158-scFv8D3 concentrations measured with PET in hippocampus and thalamus of NB-360–treated ArcSwe mice were similar to those observed in baseline animals and significantly lower than concentrations observed in same-age untreated controls. Reduced 125I-RmAb158-scFv8D3 retention was also observed with SPECT in hippocampus, cortex, and cerebellum of NB-360–treated AppNL-G-F mice. Radioligand in vivo concentrations corresponded to postmortem brain tissue analysis of soluble Aβ aggregates. For both models, mice treated with NB-360 did not display a reduced 11C-PiB signal compared with untreated controls, and further, both NB-360 and control mice tended, although not reaching significance, to show higher 11C-PiB signal than the baseline groups. Conclusion: This study demonstrated the ability of an antibody-based radioligand to detect changes in brain Aβ levels after anti-Aβ therapy in ArcSwe and AppNL-G-F mice with pronounced Aβ pathology. In contrast, the decreased Aβ levels could not be quantified with 11C-PiB PET, suggesting that these ligands detect different pools of Aβ.
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Faresjö R, Bonvicini G, Fang XT, Aguilar X, Sehlin D, Syvänen S. Brain pharmacokinetics of two BBB penetrating bispecific antibodies of different size. Fluids Barriers CNS 2021; 18:26. [PMID: 34078410 PMCID: PMC8170802 DOI: 10.1186/s12987-021-00257-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [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: 02/19/2021] [Accepted: 05/07/2021] [Indexed: 11/16/2022] Open
Abstract
Background Transferrin receptor (TfR1) mediated enhanced brain delivery of antibodies have been studied extensively in preclinical settings. However, the brain pharmacokinetics, i.e. brain entry, distribution and elimination are still not fully understood for this class of antibodies. The overall aim of the study was to compare the brain pharmacokinetics of two BBB-penetrating bispecific antibodies of different size (210 vs 58 kDa). Specifically, we wanted to investigate if the faster systemic clearance of the smaller non-IgG antibody di-scFv3D6-8D3, in comparison with the IgG-based bispecific antibody mAb3D6-scFv8D3, was also reflected in the brain. Methods Wild-type (C57/Bl6) mice were injected with 125I-iodinated ([125I]) mAb3D6-scFv8D3 (n = 46) or [125I]di-scFv3D6-8D3 (n = 32) and euthanized 2, 4, 6, 8, 10, 12, 16, or 24 h post injection. Ex vivo radioactivity in whole blood, peripheral organs and brain was measured by γ-counting. Ex vivo autoradiography and nuclear track emulsion were performed on brain sections to investigate brain and parenchymal distribution. Capillary depletion was carried out at 2, 6, and 24 h after injection of [125I]mAb3D6-scFv8D3 (n = 12) or [125I]di-scFv3D6-8D3 (n = 12), to estimate the relative levels of radiolabelled antibody in brain capillaries versus brain parenchyma. In vitro binding kinetics for [125I]mAb3D6-scFv8D3 or [125I]di-scFv3D6-8D3 to murine TfR were determined by LigandTracer. Results [125I]di-scFv3D6-8D3 showed faster elimination from blood, lower brain Cmax, and Tmax, a larger parenchymal-to-capillary concentration ratio, and a net elimination from brain at an earlier time point after injection compared with the larger [125I]mAb3D6-scFv8D3. However, the elimination rate from brain did not differ between the antibodies. The study also indicated that [125I]di-scFv3D6-8D3 displayed lower avidity than [125I]mAb3D6-scFv8D3 towards TfR1 in vitro and potentially in vivo, at least at the BBB. Conclusion A smaller size and lower TfR1 avidity are likely important for fast parenchymal delivery, while elimination of brain-associated bispecific antibodies may not be dependent on these characteristics. Supplementary Information The online version contains supplementary material available at 10.1186/s12987-021-00257-0.
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Affiliation(s)
- Rebecca Faresjö
- Department of Public Healt and Caring Sciences, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden
| | - Gillian Bonvicini
- Department of Public Healt and Caring Sciences, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden.,BioArctic AB, Warfvinges väg 35, 112 51, Stockholm, Sweden
| | - Xiaotian T Fang
- Department of Radiology and Biomedical Imaging, Yale University, Yale PET Center, 801 Howard Avenue, New Haven, CT, 06520, USA
| | - Ximena Aguilar
- Department of Public Healt and Caring Sciences, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Healt and Caring Sciences, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Healt and Caring Sciences, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden.
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29
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Rofo F, Ugur Yilmaz C, Metzendorf N, Gustavsson T, Beretta C, Erlandsson A, Sehlin D, Syvänen S, Nilsson P, Hultqvist G. Enhanced neprilysin-mediated degradation of hippocampal Aβ42 with a somatostatin peptide that enters the brain. Am J Cancer Res 2021; 11:789-804. [PMID: 33391505 PMCID: PMC7738863 DOI: 10.7150/thno.50263] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/13/2020] [Indexed: 12/21/2022] Open
Abstract
Background: Aggregation of the amyloid-beta (Aβ) peptide is one of the main neuropathological events in Alzheimer's disease (AD). Neprilysin is the major enzyme degrading Aβ, with its activity enhanced by the neuropeptide somatostatin (SST). SST levels are decreased in the brains of AD patients. The poor delivery of SST over the blood-brain barrier (BBB) and its extremely short half-life of only 3 min limit its therapeutic significance. Methods: We recombinantly fused SST to a BBB transporter binding to the transferrin receptor. Using primary neuronal cultures and neuroblastoma cell lines, the ability of the formed fusion protein to activate neprilysin was studied. SST-scFv8D3 was administered to mice overexpressing the Aβ-precursor protein (AβPP) with the Swedish mutation (APPswe) as a single injection or as a course of three injections over a 72 h period. Levels of neprilysin and Aβ were quantified using an Enzyme-linked immunosorbent assay (ELISA). Distribution of SST-scFv8D3 in the brain, blood and peripheral organs was studied by radiolabeling with iodine-125. Results: The construct, SST-scFv8D3, exhibited 120 times longer half-life than SST alone, reached the brain in high amounts when injected intravenously and significantly increased the brain concentration of neprilysin in APPswe mice. A significant decrease in the levels of membrane-bound Aβ42 was detected in the hippocampus and the adjacent cortical area after only three injections. Conclusion: With intravenous injections of our BBB permeable SST peptide, we were able to significantly increase the levels neprilysin, an effect that was followed by a significant and selective degradation of membrane-bound Aβ42 in the hippocampus. Being that membrane-bound Aβ triggers neuronal toxicity and the hippocampus is the central brain area in the progression of AD, the study has illuminated a new potential treatment paradigm with a promising safety profile targeting only the disease affected areas.
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Syvänen S, Fang XT, Faresjö R, Rokka J, Lannfelt L, Olberg DE, Eriksson J, Sehlin D. Fluorine-18-Labeled Antibody Ligands for PET Imaging of Amyloid-β in Brain. ACS Chem Neurosci 2020; 11:4460-4468. [PMID: 33236886 PMCID: PMC7747219 DOI: 10.1021/acschemneuro.0c00652] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [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] [Indexed: 12/13/2022] Open
Abstract
Antibodies are attractive as radioligands due to their outstanding specificity and high affinity, but their inability to cross the blood-brain barrier (BBB) limits their use for CNS targets. To enhance brain distribution, amyloid-β (Aβ) antibodies were fused to a transferrin receptor (TfR) antibody fragment, enabling receptor mediated transport across the BBB. The aim of this study was to label these bispecific antibodies with fluorine-18 and use them for Aβ PET imaging. Bispecific antibody ligands RmAb158-scFv8D3 and Tribody A2, both targeting Aβ and TfR, were functionalized with trans-cyclooctene (TCO) groups and conjugated with 18F-labeled tetrazines through an inverse electron demand Diels-Alder reaction performed at ambient temperature. 18F-labeling did not affect antibody binding in vitro, and initial brain uptake was high. Conjugates with the first tetrazine variant ([18F]T1) displayed high uptake in bone, indicating extensive defluorination, a problem that was resolved with the second and third tetrazine variants ([18F]T2 and [18F]T3). Although the antibody ligands' half-life in blood was too long to optimally match the physical half-life of fluorine-18 (t1/2 = 110 min), [18F]T3-Tribody A2 PET seemed to discriminate transgenic mice (tg-ArcSwe) with Aβ deposits from wild-type mice 12 h after injection. This study demonstrates that 18F-labeling of bispecific, brain penetrating antibodies is feasible and, with further optimization, could be used for CNS PET imaging.
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Affiliation(s)
- Stina Syvänen
- Department of Public Health and Caring Sciences, Rudbeck Laboratory, Uppsala University, Uppsala 751 85, Sweden
| | - Xiaotian T Fang
- Department of Public Health and Caring Sciences, Rudbeck Laboratory, Uppsala University, Uppsala 751 85, Sweden
- Department of Radiology and Biomedical Imaging, Yale University, Yale PET Center, New Haven 06520, Connecticut United States
| | - Rebecca Faresjö
- Department of Public Health and Caring Sciences, Rudbeck Laboratory, Uppsala University, Uppsala 751 85, Sweden
| | - Johanna Rokka
- Department of Public Health and Caring Sciences, Rudbeck Laboratory, Uppsala University, Uppsala 751 85, Sweden
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences, Rudbeck Laboratory, Uppsala University, Uppsala 751 85, Sweden
- BioArctic AB, Stockholm 112 51, Sweden
| | - Dag E Olberg
- Norsk medisinsk syklotronsenter AS, Oslo Postboks 4950, Norway
- Department of Pharmacy, University of Oslo, Oslo 0424, Norway
| | - Jonas Eriksson
- Department of Medicinal Chemistry, Division of Organic Pharmaceutical Chemistry, Uppsala University, Uppsala 751 23, Sweden
- PET Centre, Uppsala University Hospital, Uppsala 751 85, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Rudbeck Laboratory, Uppsala University, Uppsala 751 85, Sweden
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Zyśk M, Clausen F, Aguilar X, Sehlin D, Syvänen S, Erlandsson A. Long-Term Effects of Traumatic Brain Injury in a Mouse Model of Alzheimer's Disease. J Alzheimers Dis 2020; 72:161-180. [PMID: 31561367 PMCID: PMC6839469 DOI: 10.3233/jad-190572] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [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] [Indexed: 12/26/2022]
Abstract
Alzheimer’s disease (AD) is the leading cause of dementia worldwide, affecting over 10% of the elderly population. Epidemiological evidence indicates that traumatic brain injury (TBI) is an important risk factor for developing AD later in life. However, which injury-induced processes that contribute to the disease onset remains unclear. The aim with the present study was to identify cellular processes that could link TBI to AD development, by investigating the chronic impact of two different injury models, controlled cortical impact (CCI) and midline fluid percussion injury (mFPI). The trauma was induced in 3-month-old tg-ArcSwe mice, carrying the Arctic mutation along with the Swedish mutation, and the influence of TBI on AD progression was analyzed at 12- and 24-weeks post-injury. The long-term effect of the TBI on memory deficiency, amyloid-β (Aβ) pathology, neurodegeneration and inflammation was investigated by Morris water maze, PET imaging, immunohistochemistry, and biochemical analyses. Morris water maze analysis demonstrated that mice subjected to CCI or mFPI performed significantly worse than uninjured tg-ArcSwe mice, especially at the later time point. Moreover, the injured mice showed a late upregulation of reactive gliosis, which concurred with a more pronounced Aβ pathology, compared to uninjured AD mice. Our results suggest that the delayed glial activation following TBI may be an important link between the two diseases. However, further studies in both experimental models and human TBI patients will be required to fully elucidate the reasons why TBI increases the risk of neurodegeneration.
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Affiliation(s)
- Marlena Zyśk
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck Laboratory, Uppsala, Sweden
| | - Fredrik Clausen
- Department of Neuroscience, Uppsala University, Rudbeck Laboratory, Uppsala, Sweden
| | - Ximena Aguilar
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck Laboratory, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck Laboratory, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck Laboratory, Uppsala, Sweden
| | - Anna Erlandsson
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck Laboratory, Uppsala, Sweden
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Gustavsson T, Syvänen S, O'Callaghan P, Sehlin D. SPECT imaging of distribution and retention of a brain-penetrating bispecific amyloid-β antibody in a mouse model of Alzheimer's disease. Transl Neurodegener 2020; 9:37. [PMID: 32951598 PMCID: PMC7504681 DOI: 10.1186/s40035-020-00214-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [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: 03/30/2020] [Accepted: 08/13/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Alzheimer's disease (AD) immunotherapy with antibodies targeting amyloid-β (Aβ) has been extensively explored in clinical trials. The aim of this study was to study the long-term brain distribution of two radiolabeled monoclonal Aβ antibody variants - RmAb158, the recombinant murine version of BAN2401, which has recently demonstrated amyloid removal and reduced cognitive decline in AD patients, and the bispecific RmAb158-scFv8D3, which has been engineered for enhanced brain uptake via transferrin receptor-mediated transcytosis. METHODS A single intravenous injection of iodine-125 (125I)-labeled RmAb158-scFv8D3 or RmAb158 was administered to AD transgenic mice (tg-ArcSwe). In vivo single-photon emission computed tomography was used to investigate brain retention and intrabrain distribution of the antibodies over a period of 4 weeks. Activity in blood and brain tissue was measured ex vivo and autoradiography was performed in combination with Aβ and CD31 immunostaining to investigate the intrabrain distribution of the antibodies and their interactions with Aβ. RESULTS Despite faster blood clearance, [125I]RmAb158-scFv8D3 displayed higher brain exposure than [125I]RmAb158 throughout the study. The brain distribution of [125I]RmAb158-scFv8D3 was more uniform and coincided with parenchymal Aβ pathology, while [125I]RmAb158 displayed a more scattered distribution pattern and accumulated in central parts of the brain at later times. Ex vivo autoradiography indicated greater vascular escape and parenchymal Aβ interactions for [125I]RmAb158-scFv8D3, whereas [125I]RmAb158 displayed retention and Aβ interactions in lateral ventricles. CONCLUSIONS The high brain uptake and uniform intrabrain distribution of RmAb158-scFv8D3 highlight the benefits of receptor-mediated transcytosis for antibody-based brain imaging. Moreover, it suggests that the alternative transport route of the bispecific antibody contributes to improved efficacy of brain-directed immunotherapy.
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Affiliation(s)
- Tobias Gustavsson
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Paul O'Callaghan
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden.
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Sehlin D, Stocki P, Gustavsson T, Hultqvist G, Walsh FS, Rutkowski JL, Syvänen S. Brain delivery of biologics using a cross‐species reactive transferrin receptor 1 VNAR shuttle. FASEB J 2020; 34:13272-13283. [DOI: 10.1096/fj.202000610rr] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 07/09/2020] [Accepted: 07/16/2020] [Indexed: 11/11/2022]
Affiliation(s)
- Dag Sehlin
- Department of Public Health and Caring Sciences/Geriatrics Uppsala University Uppsala Sweden
| | - Pawel Stocki
- Ossianix, Inc. Stevenage UK
- Ossianix, Inc. Philadelphia PA USA
| | - Tobias Gustavsson
- Department of Public Health and Caring Sciences/Geriatrics Uppsala University Uppsala Sweden
| | - Greta Hultqvist
- Department of Pharmaceutical Biosciences Uppsala University Uppsala Sweden
| | - Frank S. Walsh
- Ossianix, Inc. Stevenage UK
- Ossianix, Inc. Philadelphia PA USA
| | | | - Stina Syvänen
- Department of Public Health and Caring Sciences/Geriatrics Uppsala University Uppsala Sweden
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Michno W, Wehrli P, Meier SR, Sehlin D, Syvänen S, Zetterberg H, Blennow K, Hanrieder J. Chemical imaging of evolving amyloid plaque pathology and associated Aβ peptide aggregation in a transgenic mouse model of Alzheimer’s disease. J Neurochem 2019; 152:602-616. [DOI: 10.1111/jnc.14888] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 10/01/2019] [Accepted: 10/06/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Wojciech Michno
- Department of Psychiatry and Neurochemistry Sahlgrenska Academy at the University of Gothenburg Mölndal Sweden
| | - Patrick Wehrli
- Department of Psychiatry and Neurochemistry Sahlgrenska Academy at the University of Gothenburg Mölndal Sweden
| | - Silvio R. Meier
- Department of Public Health and Caring Sciences Uppsala University Uppsala Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences Uppsala University Uppsala Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences Uppsala University Uppsala Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry Sahlgrenska Academy at the University of Gothenburg Mölndal Sweden
- Clinical Neurochemistry Laboratory Sahlgrenska University Hospital Mölndal Sweden
- UK Dementia Research Institute at UCL London UK
- Department of Neurodegenerative Disease, Queen Square Institute of Neurology University College London London UK
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry Sahlgrenska Academy at the University of Gothenburg Mölndal Sweden
- Clinical Neurochemistry Laboratory Sahlgrenska University Hospital Mölndal Sweden
| | - Jörg Hanrieder
- Department of Psychiatry and Neurochemistry Sahlgrenska Academy at the University of Gothenburg Mölndal Sweden
- Department of Neurodegenerative Disease, Queen Square Institute of Neurology University College London London UK
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Michno W, Nyström S, Wehrli P, Lashley T, Brinkmalm G, Guerard L, Syvänen S, Sehlin D, Kaya I, Brinet D, Nilsson KPR, Hammarström P, Blennow K, Zetterberg H, Hanrieder J. Pyroglutamation of amyloid-βx-42 (Aβx-42) followed by Aβ1-40 deposition underlies plaque polymorphism in progressing Alzheimer's disease pathology. J Biol Chem 2019; 294:6719-6732. [PMID: 30814252 PMCID: PMC6497931 DOI: 10.1074/jbc.ra118.006604] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [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: 11/07/2018] [Revised: 02/21/2019] [Indexed: 12/20/2022] Open
Abstract
Amyloid-β (Aβ) pathology in Alzheimer's disease (AD) is characterized by the formation of polymorphic deposits comprising diffuse and cored plaques. Because diffuse plaques are predominantly observed in cognitively unaffected, amyloid-positive (CU-AP) individuals, pathogenic conversion into cored plaques appears to be critical to AD pathogenesis. Herein, we identified the distinct Aβ species associated with amyloid polymorphism in brain tissue from individuals with sporadic AD (s-AD) and CU-AP. To this end, we interrogated Aβ polymorphism with amyloid conformation–sensitive dyes and a novel in situ MS paradigm for chemical characterization of hyperspectrally delineated plaque morphotypes. We found that maturation of diffuse into cored plaques correlated with increased Aβ1–40 deposition. Using spatial in situ delineation with imaging MS (IMS), we show that Aβ1–40 aggregates at the core structure of mature plaques, whereas Aβ1–42 localizes to diffuse amyloid aggregates. Moreover, we observed that diffuse plaques have increased pyroglutamated Aβx-42 levels in s-AD but not CU-AP, suggesting an AD pathology–related, hydrophobic functionalization of diffuse plaques facilitating Aβ1–40 deposition. Experiments in tgAPPSwe mice verified that, similar to what has been observed in human brain pathology, diffuse deposits display higher levels of Aβ1–42 and that Aβ plaque maturation over time is associated with increases in Aβ1–40. Finally, we found that Aβ1–40 deposition is characteristic for cerebral amyloid angiopathy deposition and maturation in both humans and mice. These results indicate that N-terminal Aβx-42 pyroglutamation and Aβ1–40 deposition are critical events in priming and maturation of pathogenic Aβ from diffuse into cored plaques, underlying neurotoxic plaque development in AD.
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Affiliation(s)
- Wojciech Michno
- From the Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 43180 Mölndal, Sweden
| | - Sofie Nyström
- the Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden
| | - Patrick Wehrli
- From the Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 43180 Mölndal, Sweden
| | - Tammaryn Lashley
- the Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
| | - Gunnar Brinkmalm
- From the Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 43180 Mölndal, Sweden
| | - Laurent Guerard
- the Center for Cellular Imaging, Core Facilities, Sahlgrenska Academy at the University of Gothenburg, 41390 Gothenburg, Sweden
| | - Stina Syvänen
- the Department of Public Health and Caring Sciences, Uppsala University, 75236 Uppsala, Sweden
| | - Dag Sehlin
- the Department of Public Health and Caring Sciences, Uppsala University, 75236 Uppsala, Sweden
| | - Ibrahim Kaya
- From the Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 43180 Mölndal, Sweden
| | - Dimitri Brinet
- From the Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 43180 Mölndal, Sweden
| | - K Peter R Nilsson
- the Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden
| | - Per Hammarström
- the Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden
| | - Kaj Blennow
- From the Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 43180 Mölndal, Sweden.,the Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, 43180 Mölndal, Sweden
| | - Henrik Zetterberg
- From the Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 43180 Mölndal, Sweden.,the Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, United Kingdom.,the Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, 43180 Mölndal, Sweden.,the UK Dementia Research Institute at UCL, London WC1E 6BT, United Kingdom, and
| | - Jörg Hanrieder
- From the Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 43180 Mölndal, Sweden, .,the Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
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Gustafsson S, Gustavsson T, Roshanbin S, Hultqvist G, Hammarlund-Udenaes M, Sehlin D, Syvänen S. Blood-brain barrier integrity in a mouse model of Alzheimer's disease with or without acute 3D6 immunotherapy. Neuropharmacology 2018; 143:1-9. [DOI: 10.1016/j.neuropharm.2018.09.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/27/2018] [Accepted: 09/01/2018] [Indexed: 12/13/2022]
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Fang XT, Hultqvist G, Meier SR, Antoni G, Sehlin D, Syvänen S. High detection sensitivity with antibody-based PET radioligand for amyloid beta in brain. Neuroimage 2018; 184:881-888. [PMID: 30300753 DOI: 10.1016/j.neuroimage.2018.10.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [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: 06/28/2018] [Accepted: 10/04/2018] [Indexed: 11/17/2022] Open
Abstract
PET imaging of amyloid-beta (Aβ) deposits in brain has become an important aid in Alzheimer's disease diagnosis, and an inclusion criterion for patient enrolment into clinical trials of new anti-Aβ treatments. Available PET radioligands visualizing Aβ bind to insoluble fibrils, i.e. Aβ plaques. Levels of prefibrillar Aβ forms, e.g. soluble oligomers and protofibrils, correlate better than plaques with disease severity and these soluble species are the neurotoxic form of Aβ leading to neurodegeneration. The goal was to create an antibody-based radioligand, recognizing not only fibrillary Aβ, but also smaller and still soluble aggregates. We designed and expressed a small recombinant bispecific antibody construct, di-scFv 3D6-8D3, targeting the Aβ N-terminus and the transferrin receptor (TfR). Natively expressed at the blood-brain barrier (BBB), TfR could thus be used as a brain-blood shuttle. Di-scFv 3D6-8D3 bound to Aβ1-40 with high affinity and to TfR with moderate affinity. Di-scFv [124I]3D6-8D3 was injected in two transgenic mouse models overexpressing human Aβ and wild-type control mice and PET scanned at 14, 24 or 72 h after injection. Di-scFv [124I]3D6-8D3 was retained in brain of transgenic animals while it was cleared from wild-type lacking Aβ. This difference was observed from 24 h onwards, and at 72 h, 18 months old transgenic animals, with high load of Aβ pathology, displayed SUVR of 2.2-3.5 in brain while wild-type showed ratios close to unity. A subset of the mice were also scanned with [11C]PIB. Again wt mice displayed ratios of unity while transgenes showed slightly, non-significantly, elevated SUVR of 1.2, indicating improved sensitivity with novel di-scFv [124I]3D6-8D3 compared with [11C]PIB. Brain concentrations of di-scFv [124I]3D6-8D3 correlated with soluble Aβ (p < 0.0001) but not with total Aβ, i.e. plaque load (p = 0.34). We have successfully created a small bispecific antibody-based radioligand capable of crossing the BBB, subsequently binding to and visualizing intrabrain Aβ in vivo. The radioligand displayed better sensitivity compared with [11C]PIB, and brain concentrations correlated with soluble neurotoxic Aβ aggregates.
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Affiliation(s)
- Xiaotian T Fang
- Department of Public Health and Caring Sciences / Geriatrics, Uppsala University, Uppsala, Sweden.
| | - Greta Hultqvist
- Department of Public Health and Caring Sciences / Geriatrics, Uppsala University, Uppsala, Sweden; Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Silvio R Meier
- Department of Public Health and Caring Sciences / Geriatrics, Uppsala University, Uppsala, Sweden
| | - Gunnar Antoni
- Department of Medicinal Chemistry, Preclinical PET Platform, Uppsala University, Uppsala, Sweden; PET Centre, Uppsala University Hospital, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences / Geriatrics, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences / Geriatrics, Uppsala University, Uppsala, Sweden
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Meier SR, Syvänen S, Hultqvist G, Fang XT, Roshanbin S, Lannfelt L, Neumann U, Sehlin D. Antibody-Based In Vivo PET Imaging Detects Amyloid-β Reduction in Alzheimer Transgenic Mice After BACE-1 Inhibition. J Nucl Med 2018; 59:1885-1891. [PMID: 29853653 PMCID: PMC6278900 DOI: 10.2967/jnumed.118.213140] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [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: 04/17/2018] [Accepted: 05/07/2018] [Indexed: 12/26/2022] Open
Abstract
Visualization of amyloid-β (Aβ) pathology with PET has become an important tool for making a specific clinical diagnosis of Alzheimer disease (AD). However, the available amyloid PET radioligands, such as 11C-Pittsburgh compound B, reflect levels of insoluble Aβ plaques but do not capture soluble and protofibrillar Aβ forms. Furthermore, the plaque load appears to be fairly static during clinical stages of AD and may not be affected by Aβ-reducing treatments. The aim of the present study was to investigate whether a novel PET radioligand based on an antibody directed toward soluble aggregates of Aβ can be used to detect changes in Aβ levels during disease progression and after treatment with a β-secretase (BACE-1) inhibitor. Methods: One set of transgenic mice (tg-ArcSwe, a model of Aβ pathology) aged between 7 and 16 mo underwent PET with the Aβ protofibril-selective radioligand 124I-RmAb158-scFv8D3 (where RmAb is recombinant mouse monoclonal antibody and scFv is single-chain variable fragment) to follow progression of Aβ pathology in the brain. A second set of tg-ArcSwe mice, aged 10 mo, were treated with the BACE-1 inhibitor NB-360 for 3 mo and compared with an untreated control group. A third set of tg-ArcSwe mice, also aged 10 mo, underwent PET as a baseline group. Brain tissue was isolated after PET to determine levels of Aβ by ELISA and immunohistochemistry. Results: The concentration of 124I-RmAb158-scFv8D3, as measured in vivo with PET, increased with age and corresponded well with the ex vivo autoradiography and Aβ immunohistochemistry results. Mice treated with NB-360 showed significantly lower in vivo PET signals than untreated animals and were similar to the baseline animals. The decreased 124I-RmAb158-scFv8D3 concentrations in NB-360-treated mice, as quantified with PET, corresponded well with the decreased Aβ levels measured in postmortem brain. Conclusion: Several treatments for AD are in phase 2 and 3 clinical trials, but the possibility of studying treatment effects in vivo on the important, nonfibrillar, forms of Aβ is limited. This study demonstrated the ability of the Aβ protofibril-selective radioligand 124I-RmAb158-scFv8D3 to follow disease progression and detect treatment effects with PET imaging in tg-ArcSwe mice.
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Affiliation(s)
- Silvio R Meier
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Uppsala, Sweden
| | - Greta Hultqvist
- Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Xiaotian T Fang
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Uppsala, Sweden
| | - Sahar Roshanbin
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Uppsala, Sweden
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Uppsala, Sweden.,BioArctic AB, Stockholm, Sweden; and
| | - Ulf Neumann
- Neuroscience Research, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Dag Sehlin
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Uppsala, Sweden
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Syvänen S, Hultqvist G, Gustavsson T, Gumucio A, Laudon H, Söderberg L, Ingelsson M, Lannfelt L, Sehlin D. Efficient clearance of Aβ protofibrils in AβPP-transgenic mice treated with a brain-penetrating bifunctional antibody. Alzheimers Res Ther 2018; 10:49. [PMID: 29793530 PMCID: PMC5968497 DOI: 10.1186/s13195-018-0377-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 04/30/2018] [Indexed: 11/10/2022]
Abstract
Background Amyloid-β (Aβ) immunotherapy is one of the most promising disease-modifying strategies for Alzheimer’s disease (AD). Despite recent progress targeting aggregated forms of Aβ, low antibody brain penetrance remains a challenge. In the present study, we used transferrin receptor (TfR)-mediated transcytosis to facilitate brain uptake of our previously developed Aβ protofibril-selective mAb158, with the aim of increasing the efficacy of immunotherapy directed toward soluble Aβ protofibrils. Methods Aβ protein precursor (AβPP)-transgenic mice (tg-ArcSwe) were given a single dose of mAb158, modified for TfR-mediated transcytosis (RmAb158-scFv8D3), in comparison with an equimolar dose or a tenfold higher dose of unmodified recombinant mAb158 (RmAb158). Soluble Aβ protofibrils and total Aβ in the brain were measured by enzyme-linked immunosorbent assay (ELISA). Brain distribution of radiolabeled antibodies was visualized by positron emission tomography (PET) and ex vivo autoradiography. Results ELISA analysis of Tris-buffered saline brain extracts demonstrated a 40% reduction of soluble Aβ protofibrils in both RmAb158-scFv8D3- and high-dose RmAb158-treated mice, whereas there was no Aβ protofibril reduction in mice treated with a low dose of RmAb158. Further, ex vivo autoradiography and PET imaging revealed different brain distribution patterns of RmAb158-scFv8D3 and RmAb158, suggesting that these antibodies may affect Aβ levels by different mechanisms. Conclusions With a combination of biochemical and imaging analyses, this study demonstrates that antibodies engineered to be transported across the blood-brain barrier can be used to increase the efficacy of Aβ immunotherapy. This strategy may allow for decreased antibody doses and thereby reduced side effects and treatment costs.
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Affiliation(s)
- Stina Syvänen
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 75185, Uppsala, Sweden
| | - Greta Hultqvist
- Department of Pharmaceutical biosciences, Uppsala University, Uppsala, Sweden
| | - Tobias Gustavsson
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 75185, Uppsala, Sweden
| | - Astrid Gumucio
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 75185, Uppsala, Sweden
| | | | | | - Martin Ingelsson
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 75185, Uppsala, Sweden
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 75185, Uppsala, Sweden.,BioArctic AB, Stockholm, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, 75185, Uppsala, Sweden.
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Söllvander S, Nikitidou E, Gallasch L, Zyśk M, Söderberg L, Sehlin D, Lannfelt L, Erlandsson A. The Aβ protofibril selective antibody mAb158 prevents accumulation of Aβ in astrocytes and rescues neurons from Aβ-induced cell death. J Neuroinflammation 2018; 15:98. [PMID: 29592816 PMCID: PMC5875007 DOI: 10.1186/s12974-018-1134-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [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: 01/03/2018] [Accepted: 03/19/2018] [Indexed: 11/10/2022] Open
Abstract
Background Currently, several amyloid beta (Aβ) antibodies, including the protofibril selective antibody BAN2401, are in clinical trials. The murine version of BAN2401, mAb158, has previously been shown to lower the levels of pathogenic Aβ and prevent Aβ deposition in animal models of Alzheimer’s disease (AD). However, the cellular mechanisms of the antibody’s action remain unknown. We have recently shown that astrocytes effectively engulf Aβ42 protofibrils, but store rather than degrade the ingested Aβ aggregates. In a co-culture set-up, the incomplete degradation of Aβ42 protofibrils by astrocytes results in increased neuronal cell death, due to the release of extracellular vesicles, containing N-truncated, neurotoxic Aβ. Methods The aim of the present study was to investigate if the accumulation of Aβ in astrocytes can be affected by the Aβ protofibril selective antibody mAb158. Co-cultures of astrocytes, neurons, and oligodendrocytes, derived from embryonic mouse cortex, were exposed to Aβ42 protofibrils in the presence or absence of mAb158. Results Our results demonstrate that the presence of mAb158 almost abolished Aβ accumulation in astrocytes. Consequently, mAb158 treatment rescued neurons from Aβ-induced cell death. Conclusion Based on these findings, we conclude that astrocytes may play a central mechanistic role in anti-Aβ immunotherapy. Electronic supplementary material The online version of this article (10.1186/s12974-018-1134-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sofia Söllvander
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Elisabeth Nikitidou
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Linn Gallasch
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Marlena Zyśk
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Linda Söderberg
- BioArctic AB, Warfvinges väg 35, SE-112 51, Stockholm, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Anna Erlandsson
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden.
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Abu Hamdeh S, Virhammar J, Sehlin D, Alafuzoff I, Cesarini KG, Marklund N. Brain tissue Aβ42 levels are linked to shunt response in idiopathic normal pressure hydrocephalus. J Neurosurg 2018; 130:121-129. [DOI: 10.3171/2017.7.jns171005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 07/24/2017] [Indexed: 11/06/2022]
Abstract
OBJECTIVEThe authors conducted a study to test if the cortical brain tissue levels of soluble amyloid beta (Aβ) reflect the propensity of cortical Aβ aggregate formation and may be an additional factor predicting surgical outcome following idiopathic normal pressure hydrocephalus (iNPH) treatment.METHODSHighly selective ELISAs (enzyme-linked immunosorbent assays) were used to quantify soluble Aβ40, Aβ42, and neurotoxic Aβ oligomers/protofibrils, associated with Aβ aggregation, in cortical biopsy samples obtained in patients with iNPH (n = 20), sampled during ventriculoperitoneal (VP) shunt surgery. Patients underwent pre- and postoperative (3-month) clinical assessment with a modified iNPH scale. The preoperative CSF biomarkers and the levels of soluble and insoluble Aβ species in cortical biopsy samples were analyzed for their association with a favorable outcome following the VP shunt procedure, defined as a ≥ 5-point increase in the iNPH scale.RESULTSThe brain tissue levels of Aβ42 were negatively correlated with CSF Aβ42 (Spearman’s r = −0.53, p < 0.05). The Aβ40, Aβ42, and Aβ oligomer/protofibril levels in cortical biopsy samples were higher in patients with insoluble cortical Aβ aggregates (p < 0.05). The preoperative CSF Aβ42 levels were similar in patients responding (n = 11) and not responding (n = 9) to VP shunt treatment at 3 months postsurgery. In contrast, the presence of cortical Aβ aggregates and high brain tissue Aβ42 levels were associated with a poor outcome following VP shunt treatment (p < 0.05).CONCLUSIONSBrain tissue measurements of soluble Aβ species are feasible. Since high Aβ42 levels in cortical biopsy samples obtained in patients with iNPH indicated a poor surgical outcome, tissue levels of Aβ species may be associated with the clinical response to shunt treatment.
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Affiliation(s)
- Sami Abu Hamdeh
- 1Department of Neuroscience, Section of Neurosurgery, Uppsala University
| | - Johan Virhammar
- 2Department of Neuroscience, Neurology, Uppsala University Hospital, Uppsala University
| | - Dag Sehlin
- 3Department of Public Health and Caring Sciences/Geriatrics, Uppsala University; and
| | - Irina Alafuzoff
- 4Department of Pathology, Uppsala University Hospital, Uppsala University, Uppsala, Sweden
| | | | - Niklas Marklund
- 1Department of Neuroscience, Section of Neurosurgery, Uppsala University
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Sehlin D, Fang XT, Meier SR, Jansson M, Syvänen S. Pharmacokinetics, biodistribution and brain retention of a bispecific antibody-based PET radioligand for imaging of amyloid-β. Sci Rep 2017; 7:17254. [PMID: 29222502 PMCID: PMC5722892 DOI: 10.1038/s41598-017-17358-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/23/2017] [Indexed: 11/18/2022] Open
Abstract
Monoclonal antibodies (mAbs) have not been used as positron emission tomography (PET) ligands for in vivo imaging of the brain because of their limited passage across the blood-brain barrier (BBB). However, due to their high affinity and specificity, mAbs may be an attractive option for brain PET if their brain distribution can be facilitated. In the present study, a F(ab’)2 fragment of the amyloid-beta (Aβ) protofibril selective mAb158 was chemically conjugated to the transferrin receptor (TfR) antibody 8D3 to enable TfR mediated transcytosis across the BBB. The generated bispecific protein, 8D3-F(ab’)2-h158, was subsequently radiolabeled and used for microPET imaging of Aβ pathology in two mouse models of AD. [124I]8D3-F(ab’)2-h158 was distributed across the BBB several fold more than unmodified mAbs in general and its accumulation in the brain reflected disease progression, while its concentration in blood and other organs remained stable across all age groups studied. Cerebellum was largely devoid of 8D3-F(ab’)2-h158 in young and middle aged mice, while mice older than 18 months also showed some accumulation in cerebellum. In a longer perspective, the use of bispecific antibodies as PET ligands may enable in vivo ‘immunohistochemistry’ also of other proteins in the brain for which PET radioligands are lacking.
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Affiliation(s)
- Dag Sehlin
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, SE-751 83, Uppsala, Sweden
| | - Xiaotian T Fang
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, SE-751 83, Uppsala, Sweden
| | - Silvio R Meier
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, SE-751 83, Uppsala, Sweden
| | - Malin Jansson
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, SE-751 83, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Dag Hammarskjölds väg 20, SE-751 83, Uppsala, Sweden.
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Fang XT, Sehlin D, Lannfelt L, Syvänen S, Hultqvist G. Efficient and inexpensive transient expression of multispecific multivalent antibodies in Expi293 cells. Biol Proced Online 2017; 19:11. [PMID: 28932173 PMCID: PMC5603040 DOI: 10.1186/s12575-017-0060-7] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [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: 02/24/2017] [Accepted: 08/22/2017] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Immunotherapy is a very fast expanding field within drug discovery and, hence, rapid and inexpensive expression of antibodies would be extremely valuable. Antibodies are, however, difficult to express. Multifunctional antibodies with additional binding domains further complicate the expression. Only few protocols describe the production of tetravalent bispecific antibodies and all with limited expression levels.. METHODS Here, we describe a protocol that can produce functional tetravalent, bispecific antibodies at around 22 mg protein/l to a low cost. The expression system is based on the Expi293 cells, which have been adapted to grow in denser cultures than HEK293 cells and gives higher expression yields. The new protocol transfects the Expi293 cells with PEI (which has a negligible cost). RESULTS The protocol has been used to generate multiple variants of tetra- and hexavalent bispecific antibodies with yields of around 22 mg protein/l within 10 days. All materials are commercially available and the implementation of the protocol is inexpensive and straightforward. The bispecific antibodies generated in our lab were capable of binding to all antigens with similar affinity as the original antibody. Two of the bispecific antibodies have also been used in transgenic mice as positron emission tomography (PET) ligands to successfully detect amyloid-beta (Aβ) aggregates in vivo. CONCLUSIONS This protocol is the first describing transfection of the human Expi293 cells with PEI. It can be used to generate functional multi-specific antibodies in high amounts. The use of biological drugs, and in particular multispecific antibodies, is rapidly increasing, hence improved protocols such as the one presented here are highly valuable.
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Affiliation(s)
- Xiaotian T. Fang
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck laboratory, Dag Hammarskjöldsväg 20, 751 85 Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck laboratory, Dag Hammarskjöldsväg 20, 751 85 Uppsala, Sweden
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck laboratory, Dag Hammarskjöldsväg 20, 751 85 Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck laboratory, Dag Hammarskjöldsväg 20, 751 85 Uppsala, Sweden
| | - Greta Hultqvist
- Department of Public Health and Caring Sciences, Uppsala University, Rudbeck laboratory, Dag Hammarskjöldsväg 20, 751 85 Uppsala, Sweden
- Department of Pharmaceutical biosciences, Uppsala University, Biomedical center, Husargatan 3, Box 591, 75124 Uppsala, Sweden
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Kaya I, Brinet D, Michno W, Syvänen S, Sehlin D, Zetterberg H, Blennow K, Hanrieder J. Delineating Amyloid Plaque Associated Neuronal Sphingolipids in Transgenic Alzheimer's Disease Mice (tgArcSwe) Using MALDI Imaging Mass Spectrometry. ACS Chem Neurosci 2017; 8:347-355. [PMID: 27984697 PMCID: PMC5314428 DOI: 10.1021/acschemneuro.6b00391] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [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] [Indexed: 01/17/2023] Open
Abstract
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The major pathological
hallmarks of Alzheimer’s disease
(AD) are the progressive aggregation and accumulation of beta-amyloid
(Aβ) and hyperphosphorylated tau protein into neurotoxic deposits.
Aβ aggregation has been suggested as the critical early inducer,
driving the disease progression. However, the factors that promote
neurotoxic Aβ aggregation remain elusive. Imaging mass spectrometry
(IMS) is a powerful technique to comprehensively elucidate the spatial
distribution patterns of lipids, peptides, and proteins in biological
tissue sections. In the present study, matrix-assisted laser desorption/ionization
(MALDI) mass spectrometry (MS)-based imaging was used on transgenic
Alzheimer’s disease mouse (tgArcSwe) brain tissue to investigate
the sphingolipid microenvironment of individual Aβ plaques and
elucidate plaque-associated sphingolipid alterations. Multivariate
data analysis was used to interrogate the IMS data for identifying
pathologically relevant, anatomical features based on their lipid
chemical profile. This approach revealed sphingolipid species that
distinctly located to cortical and hippocampal deposits, whose Aβ
identity was further verified using fluorescent amyloid staining and
immunohistochemistry. Subsequent multivariate statistical analysis
of the spectral data revealed significant localization of gangliosides
and ceramides species to Aβ positive plaques, which was accompanied
by distinct local reduction of sulfatides. These plaque-associated
changes in sphingolipid levels implicate a functional role of sphingolipid
metabolism in Aβ plaque pathology and AD pathogenesis. Taken
together, the presented data highlight the potential of imaging mass
spectrometry as a powerful approach for probing Aβ plaque-associated
lipid changes underlying AD pathology.
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Affiliation(s)
- Ibrahim Kaya
- Department
of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 431 80 Mölndal, Sweden
| | - Dimitri Brinet
- Department
of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 431 80 Mölndal, Sweden
- Department
of Chemistry and Molecular Biology, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - Wojciech Michno
- Department
of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 431 80 Mölndal, Sweden
| | - Stina Syvänen
- Department
of Public Health and Caring Sciences, Uppsala University, 752 37 Uppsala, Sweden
| | - Dag Sehlin
- Department
of Public Health and Caring Sciences, Uppsala University, 752 37 Uppsala, Sweden
| | - Henrik Zetterberg
- Department
of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 431 80 Mölndal, Sweden
- Clinical
Neurochemistry Laboratory, Sahlgrenska University Hospital, 431 80 Mölndal, Sweden
- Department
of Molecular Neuroscience, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
| | - Kaj Blennow
- Department
of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 431 80 Mölndal, Sweden
- Clinical
Neurochemistry Laboratory, Sahlgrenska University Hospital, 431 80 Mölndal, Sweden
| | - Jörg Hanrieder
- Department
of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, 431 80 Mölndal, Sweden
- Department
of Molecular Neuroscience, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
- Department
of Chemistry and Chemical Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
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Syvänen S, Fang XT, Hultqvist G, Meier SR, Lannfelt L, Sehlin D. A bispecific Tribody PET radioligand for visualization of amyloid-beta protofibrils - a new concept for neuroimaging. Neuroimage 2017; 148:55-63. [PMID: 28069541 DOI: 10.1016/j.neuroimage.2017.01.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [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: 10/04/2016] [Revised: 12/07/2016] [Accepted: 01/02/2017] [Indexed: 12/20/2022] Open
Abstract
Antibodies are highly specific for their target molecules, but their poor brain penetrance has restricted their use as PET ligands for imaging of targets within the CNS. The aim of this study was to develop an antibody-based radioligand, using the TribodyTM format, for PET imaging of soluble amyloid-beta (Aβ) protofibrils, which are suggested to cause neurodegeneration in Alzheimer's disease. Antibodies, even when expressed in smaller engineered formats, are large molecules that do not enter the brain in sufficient amounts for imaging purposes. Hence, their transport across the blood-brain barrier (BBB) needs to be facilitated, for example through interaction with the transferrin receptor (TfR). Thus, a Fab fragment of the TfR antibody 8D3 was fused with two single chain variable fragments (scFv) of the Aβ protofibril selective antibody mAb158. Five TribodyTM proteins (A1-A5) were generated with different linkers between the Fab-8D3 and scFv-158. All proteins bound to TfR and Aβ protofibrils in vitro. Three of the proteins (A1-A3) were radiolabeled with iodine-125 and studied ex vivo in wild-type (wt) and transgenic mice overexpressing human Aβ. The systemic pharmacokinetics were similar with half-lives in blood of around 9h for all three ligands. Brain concentrations at 2h were around 1% of the injected dose per gram brain tissue, which is similar to what is observed for small molecular radioligands and at least 10-fold higher than antibodies in general. At 72h, transgenic mice showed higher concentrations of radioactivity in the brain than wt mice (12, 15- and 16-fold for A1, A2 and A3 respectively), except in the cerebellum, an area largely devoid of Aβ pathology. A3 was then labelled with iodine-124 for in vivo positron emission tomography (PET) imaging. Brain concentrations were quantified in six different regions showing a clear distinction both quantitatively and visually between wt and transgenic mice and a good correlation with Aβ pathology. We have thus produced a recombinant, bispecific protein, actively transported into the brain, for PET imaging within the CNS. In a longer perspective, this technique may enable imaging of other proteins involved in neurodegenerative diseases for which imaging agents are completely lacking today.
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Affiliation(s)
- Stina Syvänen
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, 75185 Uppsala, Sweden.
| | - Xiaotian T Fang
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, 75185 Uppsala, Sweden.
| | - Greta Hultqvist
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, 75185 Uppsala, Sweden.
| | - Silvio R Meier
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, 75185 Uppsala, Sweden.
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, 75185 Uppsala, Sweden.
| | - Dag Sehlin
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, 75185 Uppsala, Sweden.
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Hultqvist G, Syvänen S, Fang XT, Lannfelt L, Sehlin D. Bivalent Brain Shuttle Increases Antibody Uptake by Monovalent Binding to the Transferrin Receptor. Theranostics 2017; 7:308-318. [PMID: 28042336 PMCID: PMC5197066 DOI: 10.7150/thno.17155] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 10/19/2016] [Indexed: 02/04/2023] Open
Abstract
The blood-brain barrier (BBB) is an obstacle for antibody passage into the brain, impeding the development of immunotherapy and antibody-based diagnostics for brain disorders. In the present study, we have developed a brain shuttle for active transport of antibodies across the BBB by receptor-mediated transcytosis. We have thus recombinantly fused two single-chain variable fragments (scFv) of the transferrin receptor (TfR) antibody 8D3 to the light chains of mAb158, an antibody selectively binding to Aβ protofibrils, which are involved in the pathogenesis of Alzheimer's disease (AD). Despite the two TfR binders, a monovalent interaction with TfR was achieved due to the short linkers that sterically hinder bivalent binding to the TfR dimer. The design enabled efficient receptor-mediated brain uptake of the fusion protein. Two hours after administration, brain concentrations were 2-3% of the injected dose per gram brain, comparable to small molecular drugs and 80-fold higher than unmodified mAb158. After three days, fusion protein concentrations in AD transgenic mouse brains were 9-fold higher than in wild type mice, demonstrating high in vivo specificity. Thus, our innovative recombinant design markedly increases mAb158 brain uptake, which makes it a strong candidate for improved Aβ immunotherapy and as a PET radioligand for early diagnosis and evaluation of treatment effect in AD. Moreover, this approach could be applied to any target within the brain.
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Söllvander S, Ekholm-Pettersson F, Brundin RM, Westman G, Kilander L, Paulie S, Lannfelt L, Sehlin D. Increased Number of Plasma B Cells Producing Autoantibodies Against Aβ42 Protofibrils in Alzheimer's Disease. J Alzheimers Dis 2016; 48:63-72. [PMID: 26401929 PMCID: PMC4923756 DOI: 10.3233/jad-150236] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The Alzheimer's disease (AD)-related peptide amyloid-β (Aβ) has a propensity to aggregate into various assemblies including toxic soluble Aβ protofibrils. Several studies have reported the existence of anti-Aβ antibodies in humans. However, it is still debated whether levels of anti-Aβ antibodies are altered in AD patients compared to healthy individuals. Formation of immune complexes with plasma Aβ makes it difficult to reliably measure the concentration of circulating anti-Aβ antibodies with certain immunoassays, potentially leading to an underestimation. Here we have investigated anti-Aβ antibody production on a cellular level by measuring the amount of anti-Aβ antibody producing cells instead of the plasma level of anti-Aβ antibodies. To our knowledge, this is the first time the anti-Aβ antibody response in plasma has been compared in AD patients and age-matched healthy individuals using the enzyme-linked immunospot (ELISpot) technique. Both AD patients and healthy individuals had low levels of B cells producing antibodies binding Aβ40 monomers, whereas the number of cells producing antibodies toward Aβ42 protofibrils was higher overall and significantly higher in AD compared to healthy controls. This study shows, by an alternative and reliable method, that there is a specific immune response to the toxic Aβ protofibrils, which is significantly increased in AD patients.
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Affiliation(s)
- Sofia Söllvander
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Frida Ekholm-Pettersson
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Rose-Marie Brundin
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Gabriel Westman
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Lena Kilander
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | | | - Lars Lannfelt
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Dag Sehlin
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
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48
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Söllvander S, Nikitidou E, Brolin R, Söderberg L, Sehlin D, Lannfelt L, Erlandsson A. Accumulation of amyloid-β by astrocytes result in enlarged endosomes and microvesicle-induced apoptosis of neurons. Mol Neurodegener 2016; 11:38. [PMID: 27176225 PMCID: PMC4865996 DOI: 10.1186/s13024-016-0098-z] [Citation(s) in RCA: 160] [Impact Index Per Article: 20.0] [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: 10/22/2015] [Accepted: 04/15/2016] [Indexed: 01/22/2023] Open
Abstract
Background Despite the clear physical association between activated astrocytes and amyloid-β (Aβ) plaques, the importance of astrocytes and their therapeutic potential in Alzheimer’s disease remain elusive. Soluble Aβ aggregates, such as protofibrils, have been suggested to be responsible for the widespread neuronal cell death in Alzheimer’s disease, but the mechanisms behind this remain unclear. Moreover, ineffective degradation is of great interest when it comes to the development and progression of neurodegeneration. Based on our previous results that astrocytes are extremely slow in degrading phagocytosed material, we hypothesized that astrocytes may be an important player in these processes. Hence, the aim of this study was to clarify the role of astrocytes in clearance, spreading and neuronal toxicity of Aβ. Results To examine the role of astrocytes in Aβ pathology, we added Aβ protofibrils to a co-culture system of primary neurons and glia. Our data demonstrates that astrocytes rapidly engulf large amounts of Aβ protofibrils, but then store, rather than degrade the ingested material. The incomplete digestion results in a high intracellular load of toxic, partly N-terminally truncated Aβ and severe lysosomal dysfunction. Moreover, secretion of microvesicles containing N-terminally truncated Aβ, induce apoptosis of cortical neurons. Conclusions Taken together, our results suggest that astrocytes play a central role in the progression of Alzheimer’s disease, by accumulating and spreading toxic Aβ species. Electronic supplementary material The online version of this article (doi:10.1186/s13024-016-0098-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sofia Söllvander
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Elisabeth Nikitidou
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Robin Brolin
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Linda Söderberg
- BioArctic Neuroscience AB, Warfvinges väg 35, SE-112 51, Stockholm, Sweden
| | - Dag Sehlin
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Lars Lannfelt
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Anna Erlandsson
- Department of Public Health & Caring Sciences/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, SE-751 85, Uppsala, Sweden.
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O'Callaghan P, Noborn F, Sehlin D, Li JP, Lannfelt L, Lindahl U, Zhang X. Apolipoprotein E increases cell association of amyloid-β 40 through heparan sulfate and LRP1 dependent pathways. Amyloid 2014; 21:76-87. [PMID: 24491019 DOI: 10.3109/13506129.2013.879643] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The increased risk of Alzheimer's disease (AD) associated with specific apolipoprotein E (ApoE) isoforms appears to relate to altered amyloid-β (Aβ) homeostasis. Clearance of Aβ from the brain is reduced in the presence of the AD-associated ApoE4 isoform, which may contribute to the accumulation of Aβ deposits in the parenchyma and vasculature. The low-density lipoprotein receptor-related protein 1 (LRP1) and heparan sulfate proteoglycans (HSPGs), both established ApoE receptors, are involved in Aβ uptake, with LRP1 additionally implicated in Aβ transcytosis across the blood-brain barrier. In this study, we detected the co-distribution of heparan sulfate (HS), ApoE and LRP1 in Aβ(1-40)-positive brain microvessels from individuals with Down's syndrome diagnosed with AD. In addition, ApoE was pulled-down from AD cerebrospinal fluid with anti-Aβ antibodies. Using Chinese hamster ovary cells deficient in HS or LRP1, we found that ApoE increases cell association of Aβ in a HSPG- and LRP1-dependent manner; and further, ApoE processing is altered in the absence of cellular HS. These interactions may facilitate Aβ clearance from the brain, but if overwhelmed could contribute to Aβ accumulation and the pathogenesis of AD.
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Affiliation(s)
- Paul O'Callaghan
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory C11, Uppsala University , Uppsala , Sweden
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50
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Magnusson K, Sehlin D, Syvänen S, Svedberg MM, Philipson O, Söderberg L, Tegerstedt K, Holmquist M, Gellerfors P, Tolmachev V, Antoni G, Lannfelt L, Hall H, Nilsson LNG. Specific uptake of an amyloid-β protofibril-binding antibody-tracer in AβPP transgenic mouse brain. J Alzheimers Dis 2014; 37:29-40. [PMID: 23780660 DOI: 10.3233/jad-130029] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Evidence suggests that amyloid-β (Aβ) protofibrils/oligomers are pathogenic agents in Alzheimer's disease (AD). Unfortunately, techniques enabling quantitative estimates of these species in patients or patient samples are still rather limited. Here we describe the in vitro and ex vivo characteristics of a new antibody-based radioactive ligand, [125I]mAb158, which binds to Aβ protofibrils with high affinity. [125I]mAb158 was specifically taken up in brain of transgenic mice expressing amyloid-β protein precursor (AβPP) as shown ex vivo. This was in contrast to [125I]mAb-Ly128 which does not bind to Aβ. The uptake of intraperitoneally-administered [125I]mAb158 into the brain was age- and time-dependent, and saturable in AβPP transgenic mice with modest Aβ deposition. Brain uptake was also found in young AβPP transgenic mice that were devoid of Aβ deposits, suggesting that [125I]mAb158 targets soluble Aβ protofibrils. The radioligand was diffusely located in the parenchyma, sometimes around senile plaques and only occasionally colocalized with cerebral amyloid angiopathy. A refined iodine-124-labeled version of mAb158 with much improved blood-brain barrier passage and a shorter plasma half-life might be useful for PET imaging of Aβ protofibrils.
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Affiliation(s)
- Kristina Magnusson
- Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Rudbeck Laboratory, Uppsala, Sweden
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