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Yang Y, Zhang Z. α-Synuclein pathology from the body to the brain: so many seeds so close to the central soil. Neural Regen Res 2024; 19:1463-1472. [PMID: 38051888 PMCID: PMC10883481 DOI: 10.4103/1673-5374.387967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 08/24/2023] [Indexed: 12/07/2023] Open
Abstract
ABSTRACT α-Synuclein is a protein that mainly exists in the presynaptic terminals. Abnormal folding and accumulation of α-synuclein are found in several neurodegenerative diseases, including Parkinson's disease. Aggregated and highly phosphorylated α-synuclein constitutes the main component of Lewy bodies in the brain, the pathological hallmark of Parkinson's disease. For decades, much attention has been focused on the accumulation of α-synuclein in the brain parenchyma rather than considering Parkinson's disease as a systemic disease. Recent evidence demonstrates that, at least in some patients, the initial α-synuclein pathology originates in the peripheral organs and spreads to the brain. Injection of α-synuclein preformed fibrils into the gastrointestinal tract triggers the gut-to-brain propagation of α-synuclein pathology. However, whether α-synuclein pathology can occur spontaneously in peripheral organs independent of exogenous α-synuclein preformed fibrils or pathological α-synuclein leakage from the central nervous system remains under investigation. In this review, we aimed to summarize the role of peripheral α-synuclein pathology in the pathogenesis of Parkinson's disease. We also discuss the pathways by which α-synuclein pathology spreads from the body to the brain.
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Affiliation(s)
- Yunying Yang
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, China
| | - Zhentao Zhang
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, China
- TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei Province, China
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2
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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] [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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Lan HR, Chen M, Yao SY, Chen JX, Jin KT. Bispecific antibodies revolutionizing breast cancer treatment: a comprehensive overview. Front Immunol 2023; 14:1266450. [PMID: 38111570 PMCID: PMC10725925 DOI: 10.3389/fimmu.2023.1266450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 11/16/2023] [Indexed: 12/20/2023] Open
Abstract
Breast cancer (BCa) is known as a complex and prevalent disease requiring the development of novel anticancer therapeutic approaches. Bispecific antibodies (BsAbs) have emerged as a favorable strategy for BCa treatment due to their unique ability to target two different antigens simultaneously. By targeting tumor-associated antigens (TAAs) on cancer cells, engaging immune effector cells, or blocking critical signaling pathways, BsAbs offer enhanced tumor specificity and immune system involvement, improving anti-cancer activity. Preclinical and clinical studies have demonstrated the potential of BsAbs in BCa. For example, BsAbs targeting human epidermal growth factor receptor 2 (HER2) have shown the ability to redirect immune cells to HER2-positive BCa cells, resulting in effective tumor cell killing. Moreover, targeting the PD-1/PD-L1 pathway by BsAbs has demonstrated promising outcomes in overcoming immunosuppression and enhancing immune-mediated tumor clearance. Combining BsAbs with existing therapeutic approaches, such as chemotherapy, targeted therapies, or immune checkpoint inhibitors (ICIs), has also revealed synergistic effects in preclinical models and early clinical trials, emphasizing the usefulness and potential of BsAbs in BCa treatment. This review summarizes the latest evidence about BsAbs in treating BCa and the challenges and opportunities of their use in BCa.
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Affiliation(s)
- Huan-Rong Lan
- Department of Surgical Oncology, Hangzhou Cancer Hospital, Hangzhou, Zhejiang, China
| | - Min Chen
- Department of Colorectal Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Shi-Ya Yao
- Department of Colorectal Surgery, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, Zhejiang, China
| | - Jun-Xia Chen
- Department of Gynecology, Shaoxing People’s Hospital, Shaoxing, Zhejiang, China
| | - Ke-Tao Jin
- Department of Colorectal Surgery, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, Zhejiang, China
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Pardridge WM. Treatment of Parkinson's disease with biologics that penetrate the blood-brain barrier via receptor-mediated transport. Front Aging Neurosci 2023; 15:1276376. [PMID: 38035276 PMCID: PMC10682952 DOI: 10.3389/fnagi.2023.1276376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 10/27/2023] [Indexed: 12/02/2023] Open
Abstract
Parkinson's disease (PD) is characterized by neurodegeneration of nigral-striatal neurons in parallel with the formation of intra-neuronal α-synuclein aggregates, and these processes are exacerbated by neuro-inflammation. All 3 components of PD pathology are potentially treatable with biologics. Neurotrophins, such as glial derived neurotrophic factor or erythropoietin, can promote neural repair. Therapeutic antibodies can lead to disaggregation of α-synuclein neuronal inclusions. Decoy receptors can block the activity of pro-inflammatory cytokines in brain. However, these biologic drugs do not cross the blood-brain barrier (BBB). Biologics can be made transportable through the BBB following the re-engineering of the biologic as an IgG fusion protein, where the IgG domain targets an endogenous receptor-mediated transcytosis (RMT) system within the BBB, such as the insulin receptor or transferrin receptor. The receptor-specific antibody domain of the fusion protein acts as a molecular Trojan horse to ferry the biologic into brain via the BBB RMT pathway. This review describes the re-engineering of all 3 classes of biologics (neurotrophins, decoy receptor, therapeutic antibodies) for BBB delivery and treatment of PD. Targeting the RMT pathway at the BBB also enables non-viral gene therapy of PD using lipid nanoparticles (LNP) encapsulated with plasmid DNA encoding therapeutic genes. The surface of the lipid nanoparticle is conjugated with a receptor-specific IgG that triggers RMT of the LNP across the BBB in vivo.
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Pardridge WM. Receptor-mediated drug delivery of bispecific therapeutic antibodies through the blood-brain barrier. FRONTIERS IN DRUG DELIVERY 2023; 3:1227816. [PMID: 37583474 PMCID: PMC10426772 DOI: 10.3389/fddev.2023.1227816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
Therapeutic antibody drug development is a rapidly growing sector of the pharmaceutical industry. However, antibody drug development for the brain is a technical challenge, and therapeutic antibodies for the central nervous system account for ~3% of all such agents. The principal obstacle to antibody drug development for brain or spinal cord is the lack of transport of large molecule biologics across the blood-brain barrier (BBB). Therapeutic antibodies can be made transportable through the blood-brain barrier by the re-engineering of the therapeutic antibody as a BBB-penetrating bispecific antibody (BSA). One arm of the BSA is the therapeutic antibody and the other arm of the BSA is a transporting antibody. The transporting antibody targets an exofacial epitope on a BBB receptor, and this enables receptor-mediated transcytosis (RMT) of the BSA across the BBB. Following BBB transport, the therapeutic antibody then engages the target receptor in brain. RMT systems at the BBB that are potential conduits to the brain include the insulin receptor (IR), the transferrin receptor (TfR), the insulin-like growth factor receptor (IGFR) and the leptin receptor. Therapeutic antibodies have been re-engineered as BSAs that target the insulin receptor, TfR, or IGFR RMT systems at the BBB for the treatment of Alzheimer's disease and Parkinson's disease.
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Rodger AT, ALNasser M, Carter WG. Are Therapies That Target α-Synuclein Effective at Halting Parkinson's Disease Progression? A Systematic Review. Int J Mol Sci 2023; 24:11022. [PMID: 37446200 DOI: 10.3390/ijms241311022] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 06/29/2023] [Accepted: 06/29/2023] [Indexed: 07/15/2023] Open
Abstract
There are currently no pharmacological treatments available that completely halt or reverse the progression of Parkinson's Disease (PD). Hence, there is an unmet need for neuroprotective therapies. Lewy bodies are a neuropathological hallmark of PD and contain aggregated α-synuclein (α-syn) which is thought to be neurotoxic and therefore a suitable target for therapeutic interventions. To investigate this further, a systematic review was undertaken to evaluate whether anti-α-syn therapies are effective at preventing PD progression in preclinical in vivo models of PD and via current human clinical trials. An electronic literature search was performed using MEDLINE and EMBASE (Ovid), PubMed, the Web of Science Core Collection, and Cochrane databases to collate clinical evidence that investigated the targeting of α-syn. Novel preclinical anti-α-syn therapeutics provided a significant reduction of α-syn aggregations. Biochemical and immunohistochemical analysis of rodent brain tissue demonstrated that treatments reduced α-syn-associated pathology and rescued dopaminergic neuronal loss. Some of the clinical studies did not provide endpoints since they had not yet been completed or were terminated before completion. Completed clinical trials displayed significant tolerability and efficacy at reducing α-syn in patients with PD with minimal adverse effects. Collectively, this review highlights the capacity of anti-α-syn therapies to reduce the accumulation of α-syn in both preclinical and clinical trials. Hence, there is potential and optimism to target α-syn with further clinical trials to restrict dopaminergic neuronal loss and PD progression and/or provide prophylactic protection to avoid the onset of α-syn-induced PD.
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Affiliation(s)
- Abbie T Rodger
- School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby DE22 3DT, UK
| | - Maryam ALNasser
- School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby DE22 3DT, UK
- Department of Biological Sciences, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
| | - Wayne G Carter
- School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby DE22 3DT, UK
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Düchs M, Blazevic D, Rechtsteiner P, Kenny C, Lamla T, Low S, Savistchenko J, Neumann M, Melki R, Schönberger T, Stierstorfer B, Wyatt D, Igney F, Ciossek T. AAV-mediated expression of a new conformational anti-aggregated α-synuclein antibody prolongs survival in a genetic model of α-synucleinopathies. NPJ Parkinsons Dis 2023; 9:91. [PMID: 37322068 DOI: 10.1038/s41531-023-00542-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 06/05/2023] [Indexed: 06/17/2023] Open
Abstract
Prion-like transmission of pathology in α-synucleinopathies like Parkinson's disease or multiple system atrophy is increasingly recognized as one potential mechanism to address disease progression. Active and passive immunotherapies targeting insoluble, aggregated α-synuclein are already being actively explored in the clinic with mixed outcomes so far. Here, we report the identification of 306C7B3, a highly selective, aggregate-specific α-synuclein antibody with picomolar affinity devoid of binding to the monomeric, physiologic protein. 306C7B3 binding is Ser129-phosphorylation independent and shows high affinity to several different aggregated α-synuclein polymorphs, increasing the likelihood that it can also bind to the pathological seeds assumed to drive disease progression in patients. In support of this, highly selective binding to pathological aggregates in postmortem brains of MSA patients was demonstrated, with no staining in samples from other human neurodegenerative diseases. To achieve CNS exposure of 306C7B3, an adeno-associated virus (AAV) based approach driving expression of the secreted antibody within the brain of (Thy-1)-[A30P]-hα-synuclein mice was used. Widespread central transduction after intrastriatal inoculation was ensured by using the AAV2HBKO serotype, with transduction being spread to areas far away from the inoculation site. Treatment of (Thy-1)-[A30P]-hα-synuclein mice at the age of 12 months demonstrated significantly increased survival, with 306C7B3 concentration reaching 3.9 nM in the cerebrospinal fluid. These results suggest that AAV-mediated expression of 306C7B3, targeting extracellular, presumably disease-propagating aggregates of α-synuclein, has great potential as a disease-modifying therapy for α-synucleinopathies as it ensures CNS exposure of the antibody, thereby mitigating the selective permeability of the blood-brain barrier.
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Affiliation(s)
- Matthias Düchs
- Boehringer Ingelheim Pharma GmbH & Co KG, Biberach an der Riss, Germany
| | - Dragica Blazevic
- Boehringer Ingelheim Pharma GmbH & Co KG, Biberach an der Riss, Germany
| | | | | | - Thorsten Lamla
- Boehringer Ingelheim Pharma GmbH & Co KG, Biberach an der Riss, Germany
| | - Sarah Low
- Boehringer Ingelheim USA, Ridgefield, CT, USA
| | | | - Manuela Neumann
- Molecular Neuropathology of Neurodegenerative Diseases, German Center for Neurodegenerative Diseases, Tübingen, Germany
- Department of Neuropathology, University Hospital of Tübingen, Tübingen, Germany
| | - Ronald Melki
- Institut Francois Jacob (MIRCen), CEA, CNRS, Fontenay-aux-Roses, France
| | - Tanja Schönberger
- Boehringer Ingelheim Pharma GmbH & Co KG, Biberach an der Riss, Germany
| | | | - David Wyatt
- Boehringer Ingelheim Pharma GmbH & Co KG, Biberach an der Riss, Germany
| | - Frederik Igney
- Boehringer Ingelheim Pharma GmbH & Co KG, Biberach an der Riss, Germany
| | - Thomas Ciossek
- Boehringer Ingelheim Pharma GmbH & Co KG, Biberach an der Riss, Germany.
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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: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [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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Haider A, Elghazawy NH, Dawood A, Gebhard C, Wichmann T, Sippl W, Hoener M, Arenas E, Liang SH. Translational molecular imaging and drug development in Parkinson's disease. Mol Neurodegener 2023; 18:11. [PMID: 36759912 PMCID: PMC9912681 DOI: 10.1186/s13024-023-00600-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 01/23/2023] [Indexed: 02/11/2023] Open
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disorder that primarily affects elderly people and constitutes a major source of disability worldwide. Notably, the neuropathological hallmarks of PD include nigrostriatal loss and the formation of intracellular inclusion bodies containing misfolded α-synuclein protein aggregates. Cardinal motor symptoms, which include tremor, rigidity and bradykinesia, can effectively be managed with dopaminergic therapy for years following symptom onset. Nonetheless, patients ultimately develop symptoms that no longer fully respond to dopaminergic treatment. Attempts to discover disease-modifying agents have increasingly been supported by translational molecular imaging concepts, targeting the most prominent pathological hallmark of PD, α-synuclein accumulation, as well as other molecular pathways that contribute to the pathophysiology of PD. Indeed, molecular imaging modalities such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) can be leveraged to study parkinsonism not only in animal models but also in living patients. For instance, mitochondrial dysfunction can be assessed with probes that target the mitochondrial complex I (MC-I), while nigrostriatal degeneration is typically evaluated with probes designed to non-invasively quantify dopaminergic nerve loss. In addition to dopaminergic imaging, serotonin transporter and N-methyl-D-aspartate (NMDA) receptor probes are increasingly used as research tools to better understand the complexity of neurotransmitter dysregulation in PD. Non-invasive quantification of neuroinflammatory processes is mainly conducted by targeting the translocator protein 18 kDa (TSPO) on activated microglia using established imaging agents. Despite the overwhelming involvement of the brain and brainstem, the pathophysiology of PD is not restricted to the central nervous system (CNS). In fact, PD also affects various peripheral organs such as the heart and gastrointestinal tract - primarily via autonomic dysfunction. As such, research into peripheral biomarkers has taken advantage of cardiac autonomic denervation in PD, allowing the differential diagnosis between PD and multiple system atrophy with probes that visualize sympathetic nerve terminals in the myocardium. Further, α-synuclein has recently gained attention as a potential peripheral biomarker in PD. This review discusses breakthrough discoveries that have led to the contemporary molecular concepts of PD pathophysiology and how they can be harnessed to develop effective imaging probes and therapeutic agents. Further, we will shed light on potential future trends, thereby focusing on potential novel diagnostic tracers and disease-modifying therapeutic interventions.
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Affiliation(s)
- Ahmed Haider
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114 USA
- Department of Radiology and Imaging Sciences, Emory University, 101 Woodruff Circle, Atlanta, GA 30322 USA
| | - Nehal H. Elghazawy
- Biochemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Main Entrance of Al-Tagamoa Al-Khames, Cairo, 11835 Egypt
- Molecular Genetics Research Team (MGRT), Pharmaceutical Biology Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Main Entrance of Al-Tagamoa Al-Khames, Cairo, 11835 Egypt
| | - Alyaa Dawood
- Biochemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Main Entrance of Al-Tagamoa Al-Khames, Cairo, 11835 Egypt
- Molecular Genetics Research Team (MGRT), Pharmaceutical Biology Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Main Entrance of Al-Tagamoa Al-Khames, Cairo, 11835 Egypt
| | - Catherine Gebhard
- Department of Nuclear Medicine, University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland
- Center for Molecular Cardiology, University of Zurich, Schlieren, Switzerland
| | - Thomas Wichmann
- Department of Neurology/School of Medicine, Yerkes National Primate Research Center, Emory University, Atlanta, GA USA
| | - Wolfgang Sippl
- Institute of Pharmacy, Department of Medicinal Chemistry, Martin-Luther-University Halle-Wittenberg, W.-Langenbeck-Str. 4, 06120 Halle, Germany
| | - Marius Hoener
- Neuroscience and Rare Diseases Discovery and Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Ernest Arenas
- Karolinska Institutet, MBB, Molecular Neurobiology, Stockholm, Sweden
| | - Steven H. Liang
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114 USA
- Department of Radiology and Imaging Sciences, Emory University, 101 Woodruff Circle, Atlanta, GA 30322 USA
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Petersen I, Ali MI, Petrovic A, Ytterberg AJ, Staxäng K, Hodik M, Rofo F, Bondza S, Hultqvist G. Multivalent design of the monoclonal SynO2 antibody improves binding strength to soluble α-Synuclein aggregates. MAbs 2023; 15:2256668. [PMID: 37737124 PMCID: PMC10519360 DOI: 10.1080/19420862.2023.2256668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 09/05/2023] [Indexed: 09/23/2023] Open
Abstract
Soluble aggregates are reported to be the most neurotoxic species of α-Synuclein (αSyn) in Parkinson's disease (PD) and hence are a promising target for diagnosis and treatment of PD. However, the predominantly intracellular location of αSyn limits its accessibility, especially for antibody-based molecules and prompts the need for exceptionally strong soluble αSyn aggregate binders to enhance their sensitivity and efficacy for targeting the extracellular αSyn pool. In this study, we have created the multivalent antibodies TetraSynO2 and HexaSynO2, derived from the αSyn oligomer-specific antibody SynO2, to increase avidity binding to soluble αSyn aggregate species through more binding sites in close proximity. The multivalency was achieved through recombinant fusion of single-chain variable fragments of SynO2 to the antibodies' original N-termini. Our ELISA results indicated a 20-fold increased binding strength of the multivalent formats to αSyn aggregates, while binding to αSyn monomers and unspecific binding to amyloid β protofibrils remained low. Kinetic analysis using LigandTracer revealed that only 80% of SynO2 bound bivalently to soluble αSyn aggregates, whereas the proportion of TetraSynO2 and HexaSynO2 binding bi- or multivalently to soluble αSyn aggregates was increased to ~ 95% and 100%, respectively. The overall improved binding strength of TetraSynO2 and HexaSynO2 implies great potential for immunotherapeutic and diagnostic applications with targets of limited accessibility, like extracellular αSyn aggregates. The ability of the multivalent antibodies to bind a wider range of αSyn aggregate species, which are not targetable by conventional bivalent antibodies, thus could allow for an earlier and more effective intervention in the progression of PD.
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Affiliation(s)
- Inga Petersen
- Department of Pharmacy, Uppsala University, Uppsala, Sweden
| | | | - Alex Petrovic
- Department of Pharmacy, Uppsala University, Uppsala, Sweden
| | - Anders Jimmy Ytterberg
- Department of Pharmacy, SciLifeLab Drug Discovery and Development, Uppsala University, Uppsala, Sweden
| | - Karin Staxäng
- TEM Laboratory, BioVis Platform, Uppsala University, Uppsala, Sweden
| | - Monika Hodik
- TEM Laboratory, BioVis Platform, Uppsala University, Uppsala, Sweden
| | - Fadi Rofo
- Department of Pharmacy, Uppsala University, Uppsala, Sweden
| | - Sina Bondza
- Ridgeview Instruments AB, Uppsala, Sweden
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
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Pardridge WM. Advanced Blood-Brain Barrier Drug Delivery. Pharmaceutics 2022; 15:pharmaceutics15010093. [PMID: 36678722 PMCID: PMC9866552 DOI: 10.3390/pharmaceutics15010093] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 12/06/2022] [Indexed: 12/29/2022] Open
Abstract
This Special Issue of Pharmaceutics, "Advanced Blood-Brain Barrier Drug Delivery," comprises 16 articles or reviews, which cover a cross-section of brain drug delivery for either small-molecule or large-molecule therapeutics [...].
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Affiliation(s)
- William M Pardridge
- Department of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
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