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Tsai RM, Bejanin A, Lesman-Segev O, LaJoie R, Visani A, Bourakova V, O’Neil JP, Janabi M, Baker S, Lee SE, Perry DC, Bajorek L, Karydas A, Spina S, Grinberg LT, Seeley WW, Ramos EM, Coppola G, Gorno-Tempini ML, Miller BL, Rosen HJ, Jagust W, Boxer AL, Rabinovici GD. 18F-flortaucipir (AV-1451) tau PET in frontotemporal dementia syndromes. Alzheimers Res Ther 2019; 11:13. [PMID: 30704514 PMCID: PMC6357510 DOI: 10.1186/s13195-019-0470-7] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 01/17/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND The tau positron emission tomography (PET) ligand 18F-flortaucipir binds to paired helical filaments of tau in aging and Alzheimer's disease (AD), but its utility in detecting tau aggregates in frontotemporal dementia (FTD) is uncertain. METHODS We performed 18F-flortaucipir imaging in patients with the FTD syndromes (n = 45): nonfluent variant primary progressive aphasia (nfvPPA) (n = 11), corticobasal syndrome (CBS) (n = 10), behavioral variant frontotemporal dementia (bvFTD) (n = 10), semantic variant primary progressive aphasia (svPPA) (n = 2) and FTD associated pathogenic genetic mutations microtubule-associated protein tau (MAPT) (n = 6), chromosome 9 open reading frame 72 (C9ORF72) (n = 5), and progranulin (GRN) (n = 1). All patients underwent MRI and β-amyloid biomarker testing via 11C-PiB or cerebrospinal fluid. 18F-flortaucipir uptake in patients was compared to 53 β-amyloid negative normal controls using voxelwise and pre-specified region of interest approaches. RESULTS On qualitative assessment, patients with nfvPPA showed elevated 18F-flortacupir binding in the left greater than right inferior frontal gyrus. Patients with CBS showed elevated binding in frontal white matter, with higher cortical gray matter uptake in a subset of β-amyloid-positive patients. Five of ten patients with sporadic bvFTD demonstrated increased frontotemporal binding. MAPT mutation carriers had elevated 18F-flortaucipir retention primarily, but not exclusively, in mutations with Alzheimer's-like neurofibrillary tangles. However, tracer retention was also seen in patients with svPPA, and the mutations C9ORF72, GRN predicted to have TDP-43 pathology. Quantitative region-of-interest differences between patients and controls were seen only in inferior frontal gyrus in nfvPPA and left insula and bilateral temporal poles in MAPT carriers. No significant regional differences were found in CBS or sporadic bvFTD. Two patients underwent postmortem neuropathological examination. A patient with C9ORF72, TDP-43-type B pathology, and incidental co-pathology of scattered neurofibrillary tangles in the middle frontal, inferior temporal gyrus showed corresponding mild 18F-flortaucipir retention without additional uptake matching the widespread TDP-43 type B pathology. A patient with sporadic bvFTD demonstrated punctate inferior temporal and hippocampus tracer retention, corresponding to the area of severe argyrophilic grain disease pathology. CONCLUSIONS 18F-flortaucipir in patients with FTD and predicted tauopathy or TDP-43 pathology demonstrated limited sensitivity and specificity. Further postmortem pathological confirmation and development of FTD tau-specific ligands are needed.
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Affiliation(s)
- Richard M. Tsai
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Alexandre Bejanin
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Orit Lesman-Segev
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Renaud LaJoie
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Adrienne Visani
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Viktoriya Bourakova
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - James P. O’Neil
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, USA
| | - Mustafa Janabi
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, USA
| | - Suzanne Baker
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, USA
| | - Suzee E. Lee
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - David C. Perry
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Lynn Bajorek
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Anna Karydas
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Salvatore Spina
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Lea T. Grinberg
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - William W. Seeley
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Eliana M. Ramos
- Departments of Psychiatry and Neurology, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, CA USA
| | - Giovanni Coppola
- Departments of Psychiatry and Neurology, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, CA USA
| | - Maria Luisa Gorno-Tempini
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Bruce L. Miller
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Howard J. Rosen
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - William Jagust
- Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, USA
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, USA
| | - Adam L. Boxer
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
| | - Gil D. Rabinovici
- Memory and Aging Center, University of California at San Francisco, 675 Nelson Rising Lane, Suite 190, San Francisco, CA USA
- Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, USA
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Hansen AK, Brooks DJ, Borghammer P. MAO-B Inhibitors Do Not Block In Vivo Flortaucipir([ 18F]-AV-1451) Binding. Mol Imaging Biol 2019; 20:356-360. [PMID: 29127552 DOI: 10.1007/s11307-017-1143-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE Recent evidence suggests that the tau radiotracer [18F]THK-5351 displays high affinity for the monoamine oxidase type B (MAO-B) enzyme. Utilizing another tau-tracer, flortaucipir ([18F]AV-1451), we previously reported that non-demented Parkinson's disease patients show off-target binding in subcortical structures, but no appreciable cortical uptake. However, 59 % of these patients were receiving MAO-B inhibitors at the time of their scan. Here, we retrospectively investigated if MAO-B inhibitors in clinical doses affect flortaucipir binding. PROCEDURES We compared the standard uptake values of flortaucipir at regional and voxel levels in Parkinson's disease patients who received MAO-B inhibitors with those who did not. RESULTS Sixteen of 27 Parkinson's disease patients received MAO-B inhibitors at the time of scan. We found no significant flortaucipir uptake differences between the groups at voxel or regional levels. CONCLUSION Use of MAO-B inhibitors at pharmaceutical levels did not significantly affect flortaucipir binding. Thus, MAO-B does not appear to be a significant binding target of flortaucipir.
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Affiliation(s)
- Allan K Hansen
- Department of Nuclear Medicine and PET-Centre, Institute of Clinical Medicine, Aarhus University, Norrebrogade 44, bld. 10G, DK-8000, Aarhus C, Denmark.
| | - David J Brooks
- Department of Nuclear Medicine and PET-Centre, Institute of Clinical Medicine, Aarhus University, Norrebrogade 44, bld. 10G, DK-8000, Aarhus C, Denmark.,Division of Neuroscience, Department of Medicine, Imperial College London, London, UK.,Division of Neuroscience, Newcastle University, Newcastle, UK
| | - Per Borghammer
- Department of Nuclear Medicine and PET-Centre, Institute of Clinical Medicine, Aarhus University, Norrebrogade 44, bld. 10G, DK-8000, Aarhus C, Denmark
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Robinson ME, McKee AC, Salat DH, Rasmusson AM, Radigan LJ, Catana C, Milberg WP, McGlinchey RE. Positron emission tomography of tau in Iraq and Afghanistan Veterans with blast neurotrauma. Neuroimage Clin 2019; 21:101651. [PMID: 30642757 PMCID: PMC6412062 DOI: 10.1016/j.nicl.2019.101651] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 12/04/2018] [Accepted: 01/01/2019] [Indexed: 12/14/2022]
Abstract
Military personnel are often exposed to multiple instances of various types of head trauma. As a result, there has been increasing concern recently over identifying when head trauma has resulted in a brain injury and what, if any, long-term consequences those brain injuries may have. Efforts to develop equipment to protect soldiers from these long-term consequences will first require understanding the types of head trauma that are likely responsible. In this study, we sought to identify the types of head trauma most likely to lead to the deposition of tau, a protein identified as a likely indicator of long-term negative consequences of brain injury. To define the types of head trauma in a military population, we applied a factor analysis to interviews from a larger cohort of 428 Veterans enrolled in the Translational Research Center for Traumatic Brain Injury and Stress Disorders. Three factors were identified: Blast Exposure, Symptom Duration, and Blunt Concussion. Sixteen male Veterans from this study and one additional male civilian (aged 25-69, mean 35.2 years) underwent simultaneous positron emission tomography/magnetic resonance imaging using a tracer that binds to tau protein, the ligand T807/AV-1451 (Flortaucipir). Standard uptake value ratios to the isthmus of the cingulate were calculated from a 20-minute time frame 70 min post-injection. We found that tracer uptake throughout the brain was associated with Blast Exposure factor beta weights, but not with either Symptom Duration or Blunt Concussion. Associations with uptake were located primarily in the cerebellar, occipital, inferior temporal and frontal regions. The data suggest that in this small, relatively young cohort of Veterans, elevated T807/AV-1451 uptake is associated with exposure to blast neurotrauma. These findings are unanticipated, as they do not match histopathological descriptions of tau pathology associated with head trauma. Continued work will be necessary to understand the nature of the regional T807/AV-1451 uptake and any associations with clinical symptoms.
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Affiliation(s)
- Meghan E Robinson
- Translational Research Center for TBI and Stress Disorders (TRACTS), VA Boston Healthcare System, United States; Neuroimaging Research for Veterans (NeRVe) Center, VA Boston Healthcare System, United States; Department of Neurology, Boston University School of Medicine, United States.
| | - Ann C McKee
- Translational Research Center for TBI and Stress Disorders (TRACTS), VA Boston Healthcare System, United States; Department of Neurology, Boston University School of Medicine, United States; Department of Pathology and Laboratory Medicine, VA Boston Healthcare System, United States; CTE Program, Alzheimer's Disease Center, Boston University School of Medicine, United States; Department of Pathology, Boston University School of Medicine, United States
| | - David H Salat
- Translational Research Center for TBI and Stress Disorders (TRACTS), VA Boston Healthcare System, United States; Neuroimaging Research for Veterans (NeRVe) Center, VA Boston Healthcare System, United States; Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, United States
| | - Ann M Rasmusson
- National Center for PTSD, Women's Health Science Division, Department of Veterans Affairs, VA Boston Healthcare System, United States; Department of Psychiatry, Boston University School of Medicine, United States
| | - Lauren J Radigan
- Translational Research Center for TBI and Stress Disorders (TRACTS), VA Boston Healthcare System, United States
| | - Ciprian Catana
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, United States
| | - William P Milberg
- Translational Research Center for TBI and Stress Disorders (TRACTS), VA Boston Healthcare System, United States; Geriatric Research Education and Clinical Core, VA Boston Healthcare System, United States; Department of Psychiatry, Harvard Medical School, United States
| | - Regina E McGlinchey
- Translational Research Center for TBI and Stress Disorders (TRACTS), VA Boston Healthcare System, United States; Geriatric Research Education and Clinical Core, VA Boston Healthcare System, United States; Department of Psychiatry, Harvard Medical School, United States
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Abstract
Though less common than Parkinson's disease (PD), the atypical Parkinson disorders such as such as dementia with Lewy bodies, multiple system atrophy, progressive supranuclear palsy, and corticobasal degeneration are increasingly recognized and important to distinguish from PD. Atypical or "Parkinson-plus" disorders are multisystem disorders and generally progress more rapidly and respond poorly to current therapies compared to PD. Recent advances in our understanding of the pathophysiology of these disorders, however, have generated new interest in the development of novel diagnostics and disease-modifying therapeutics aimed at identifying and treating these disorders. In this review we discuss the clinical approach to the atypical Parkinson disorders and the recent developments in diagnostic and research criteria that take into account the phenotypic heterogeneity and advances in our understanding of the pathophysiology of these disorders.
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105
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Leuzy A, Chiotis K, Lemoine L, Gillberg PG, Almkvist O, Rodriguez-Vieitez E, Nordberg A. Tau PET imaging in neurodegenerative tauopathies-still a challenge. Mol Psychiatry 2019; 24:1112-1134. [PMID: 30635637 PMCID: PMC6756230 DOI: 10.1038/s41380-018-0342-8] [Citation(s) in RCA: 375] [Impact Index Per Article: 75.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 10/19/2018] [Accepted: 11/26/2018] [Indexed: 12/14/2022]
Abstract
The accumulation of pathological misfolded tau is a feature common to a collective of neurodegenerative disorders known as tauopathies, of which Alzheimer's disease (AD) is the most common. Related tauopathies include progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), Down's syndrome (DS), Parkinson's disease (PD), and dementia with Lewy bodies (DLB). Investigation of the role of tau pathology in the onset and progression of these disorders is now possible due the recent advent of tau-specific ligands for use with positron emission tomography (PET), including first- (e.g., [18F]THK5317, [18F]THK5351, [18F]AV1451, and [11C]PBB3) and second-generation compounds [namely [18F]MK-6240, [18F]RO-948 (previously referred to as [18F]RO69558948), [18F]PI-2620, [18F]GTP1, [18F]PM-PBB3, and [18F]JNJ64349311 ([18F]JNJ311) and its derivative [18F]JNJ-067)]. In this review we describe and discuss findings from in vitro and in vivo studies using both initial and new tau ligands, including their relation to biomarkers for amyloid-β and neurodegeneration, and cognitive findings. Lastly, methodological considerations for the quantification of in vivo ligand binding are addressed, along with potential future applications of tau PET, including therapeutic trials.
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Affiliation(s)
- Antoine Leuzy
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Konstantinos Chiotis
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden ,0000 0000 9241 5705grid.24381.3cTheme Neurology, Karolinska University Hospital, Stockholm, Sweden
| | - Laetitia Lemoine
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Per-Göran Gillberg
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Ove Almkvist
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden ,0000 0004 1936 9377grid.10548.38Department of Psychology, Stockholm University, Stockholm, Sweden
| | - Elena Rodriguez-Vieitez
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Agneta Nordberg
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden. .,Theme Aging, Karolinska University Hospital, Stockholm, Sweden.
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Schöll M, Maass A, Mattsson N, Ashton NJ, Blennow K, Zetterberg H, Jagust W. Biomarkers for tau pathology. Mol Cell Neurosci 2018; 97:18-33. [PMID: 30529601 PMCID: PMC6584358 DOI: 10.1016/j.mcn.2018.12.001] [Citation(s) in RCA: 148] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 12/01/2018] [Indexed: 12/14/2022] Open
Abstract
The aggregation of fibrils of hyperphosphorylated and C-terminally truncated microtubule-associated tau protein characterizes 80% of all dementia disorders, the most common neurodegenerative disorders. These so-called tauopathies are hitherto not curable and their diagnosis, especially at early disease stages, has traditionally proven difficult. A keystone in the diagnosis of tauopathies was the development of methods to assess levels of tau protein in vivo in cerebrospinal fluid, which has significantly improved our knowledge about these conditions. Tau proteins have also been measured in blood, but the importance of tau-related changes in blood is still unclear. The recent addition of positron emission tomography ligands to visualize, map and quantify tau pathology has further contributed with information about the temporal and spatial characteristics of tau accumulation in the living brain. Together, the measurement of tau with fluid biomarkers and positron emission tomography constitutes the basis for a highly active field of research. This review describes the current state of biomarkers for tau biomarkers derived from neuroimaging and from the analysis of bodily fluids and their roles in the detection, diagnosis and prognosis of tau-associated neurodegenerative disorders, as well as their associations with neuropathological findings, and aims to provide a perspective on how these biomarkers might be employed prospectively in research and clinical settings. Biomarkers for tau pathology are now essential to the research framework in the diagnosis of Alzheimer's disease (AD) Measurement of t- and p-tau has been possible in cerebrospinal fluid (CSF) for some time, the recent development of positron emission tomography (PET) ligands binding to tau has added the possibility to map and quantify tau in the living brain First-generation tau PET ligands bind predominantly to AD-typical 3R/4R tau isoforms and exhibit off-target binding that can limit accurate ligand uptake quantification Second-generation tau PET ligands appear to bind to comparable binding sites but exhibit fewer issues with brain off-target binding Biomarkers for tau derived from CSF analysis and PET could provide complementary information about disease state and stage At this time, T-tau, but not p-tau, can be reliably measured in plasma using ultra-sensitive immunoassays.
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Affiliation(s)
- Michael Schöll
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Gothenburg, Sweden; Clinical Memory Research Unit, Lund University, Malmö, Sweden; Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK.
| | - Anne Maass
- German Center for Neurodegenerative Diseases, Magdeburg, Germany; Helen Wills Neuroscience Institute, University of California, Berkeley, USA
| | - Niklas Mattsson
- Clinical Memory Research Unit, Lund University, Malmö, Sweden; Department of Neurology, Skåne University Hospital, Lund, Sweden
| | - Nicholas J Ashton
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Gothenburg, Sweden; King's College London, Institute of Psychiatry, Psychology & Neuroscience, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK; Department of Psychiatry and Neurochemistry, University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden; UK Dementia Research Institute at UCL, London, UK
| | - William Jagust
- Helen Wills Neuroscience Institute, University of California, Berkeley, USA; Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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Cho H, Kim HJ, Choi JY, Ryu YH, Lee MS, Na DL, Seo SW, Lyoo CH. 18F-flortaucipir uptake patterns in clinical subtypes of primary progressive aphasia. Neurobiol Aging 2018; 75:187-197. [PMID: 30594046 DOI: 10.1016/j.neurobiolaging.2018.11.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 11/14/2018] [Accepted: 11/15/2018] [Indexed: 11/19/2022]
Abstract
We analyzed 18F-flortaucipir uptake patterns and structural changes in patients with subtypes of primary progressive aphasia (PPA) using 18F-flortaucipir positron emission tomography and volumetric magnetic resonance imaging. We enrolled 34 consecutive patients with PPA (10 nonfluent/agrammatic PPA [nfvPPA], 18 semantic variant PPA [svPPA], and 6 logopenic variant PPA [lvPPA], as well as 20 healthy controls, and 20 patients with Alzheimer's disease. 18F-flortaucipir uptake was increased in the frontal cortex and underlying white matter, and subcortical nuclei in the 10 nfvPPA and 8 nfvPPA-amyloid-β (Aβ)- subgroup patients. In the svPPA patients (both the 13 svPPA-Aβ- and 5 svPPA-Aβ+), uptake generally increased in the widespread neocortex with left anterior temporal predominance. 18F-flortaucipir uptake patterns in the 6 lvPPA and the 5 lvPPA-Aβ+ subgroup patients were similar to those seen in the patients with Alzheimer's disease with mild predominance in the left lateral temporal cortex. Cortical thinning in each PPA subtype corresponded with increased 18F-flortaucipir uptake. 18F-flortaucipir uptake patterns and cortical atrophy were distinct and corresponded to areas related to the specific language functions that are impaired in each subtype of PPA.
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Affiliation(s)
- Hanna Cho
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hee Jin Kim
- Departments of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jae Yong Choi
- Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea; Division of RI-Convergence Research, Korea Institute Radiological and Medical Sciences, Seoul, South Korea
| | - Young Hoon Ryu
- Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Myung Sik Lee
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Duk L Na
- Departments of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sang Won Seo
- Departments of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
| | - Chul Hyoung Lyoo
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
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Femminella GD, Thayanandan T, Calsolaro V, Komici K, Rengo G, Corbi G, Ferrara N. Imaging and Molecular Mechanisms of Alzheimer's Disease: A Review. Int J Mol Sci 2018; 19:E3702. [PMID: 30469491 PMCID: PMC6321449 DOI: 10.3390/ijms19123702] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 11/13/2018] [Accepted: 11/14/2018] [Indexed: 02/07/2023] Open
Abstract
Alzheimer's disease is the most common form of dementia and is a significant burden for affected patients, carers, and health systems. Great advances have been made in understanding its pathophysiology, to a point that we are moving from a purely clinical diagnosis to a biological one based on the use of biomarkers. Among those, imaging biomarkers are invaluable in Alzheimer's, as they provide an in vivo window to the pathological processes occurring in Alzheimer's brain. While some imaging techniques are still under evaluation in the research setting, some have reached widespread clinical use. In this review, we provide an overview of the most commonly used imaging biomarkers in Alzheimer's disease, from molecular PET imaging to structural MRI, emphasising the concept that multimodal imaging would likely prove to be the optimal tool in the future of Alzheimer's research and clinical practice.
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Affiliation(s)
| | - Tony Thayanandan
- Imperial Memory Unit, Charing Cross Hospital, Imperial College London, London W6 8RF, UK.
| | - Valeria Calsolaro
- Neurology Imaging Unit, Imperial College London, London W12 0NN, UK.
| | - Klara Komici
- Department of Medicine and Health Sciences, University of Molise, 86100 Campobasso, Italy.
| | - Giuseppe Rengo
- Department of Translational Medical Sciences, Federico II University of Naples, 80131 Naples, Italy.
- Istituti Clinici Scientifici Maugeri SPA-Società Benefit, IRCCS, 82037 Telese Terme, Italy.
| | - Graziamaria Corbi
- Department of Medicine and Health Sciences, University of Molise, 86100 Campobasso, Italy.
| | - Nicola Ferrara
- Department of Translational Medical Sciences, Federico II University of Naples, 80131 Naples, Italy.
- Istituti Clinici Scientifici Maugeri SPA-Società Benefit, IRCCS, 82037 Telese Terme, Italy.
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Steinacker P, Barschke P, Otto M. Biomarkers for diseases with TDP-43 pathology. Mol Cell Neurosci 2018; 97:43-59. [PMID: 30399416 DOI: 10.1016/j.mcn.2018.10.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 10/26/2018] [Accepted: 10/29/2018] [Indexed: 01/01/2023] Open
Abstract
The discovery that aggregated transactive response DNA-binding protein 43 kDa (TDP-43) is the major component of pathological ubiquitinated inclusions in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) caused seminal progress in the unveiling of the genetic bases and molecular characteristics of these now so-called TDP-43 proteinopathies. Substantial increase in the knowledge of clinic-pathological coherencies, especially for FTLD variants, could be made in the last decade, but also revealed a considerable complexity of TDP-43 pathology and often a poor correlation of clinical and molecular disease characteristics. To date, an underlying TDP-43 pathology can be predicted only for patients with mutations in the genes C9orf72 and GRN, but is dependent on neuropathological verification in patients without family history, which represent the majority of cases. As etiology-specific therapies for neurodegenerative proteinopathies are emerging, methods to forecast TDP-43 pathology at patients' lifetime are highly required. Here, we review the current status of research pursued to identify specific indicators to predict or exclude TDP-43 pathology in the ALS-FTLD spectrum disorders and findings on candidates for prognosis and monitoring of disease progression in TDP-43 proteinopathies with a focus on TDP-43 with its pathological forms, neurochemical and imaging biomarkers.
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Affiliation(s)
| | - Peggy Barschke
- Department of Neurology, University of Ulm, Ulm, Germany
| | - Markus Otto
- Department of Neurology, University of Ulm, Ulm, Germany.
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111
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Tau PET imaging evidence in patients with cognitive impairment: preparing for clinical use. Clin Transl Imaging 2018. [DOI: 10.1007/s40336-018-0297-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Abstract
PURPOSE OF REVIEW Differential diagnosis of atypical Parkinson syndromes (APS) is difficult as clinical presentations may vary and as there is a strong overlap between disease entities. Aggregations of misfolded and hyperphosphorylated tau proteins are the common denominator of many of these diseases. RECENT FINDINGS Several tau targeting positron emission tomography (PET) tracers have been evaluated as possible biomarkers in APS in the recent years. For Parkinson's disease, dementia with Lewy bodies, progressive supranuclear palsy, and corticobasal degeneration, promising results have been reported with regard to the ability to detect the presence of disease and to discriminate patients from controls. However, the discussion about the specificity of the first-generation radiotracers and their value in the clinical context is ongoing. A combined interpretation of signal strength and distribution pattern in PET scans with first- and second-generation tracers may be helpful in clinical diagnosis and follow-up of patients with APS.
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113
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Makaretz SJ, Quimby M, Collins J, Makris N, McGinnis S, Schultz A, Vasdev N, Johnson KA, Dickerson BC. Flortaucipir tau PET imaging in semantic variant primary progressive aphasia. J Neurol Neurosurg Psychiatry 2018; 89:1024-1031. [PMID: 28986472 PMCID: PMC5964045 DOI: 10.1136/jnnp-2017-316409] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 07/07/2017] [Accepted: 07/18/2017] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The semantic variant of primary progressive aphasia (svPPA) is typically associated with frontotemporal lobar degeneration (FTLD) with longTAR DNA-binding protein (TDP)-43-positive neuropil threads and dystrophic neurites (type C), and is only rarely due to a primary tauopathy or Alzheimer's disease. We undertook this study to investigate the localisation and magnitude of the presumed tau Positron Emission Tomography (PET) tracer [18F]Flortaucipir (FTP; also known as T807 or AV1451) in patients with svPPA, hypothesising that most patients would not show tracer uptake different from controls. METHODS FTP and [11C]Pittsburgh compound B PET imaging as well as MRI were performed in seven patients with svPPA and in 20 controls. FTP signal was analysed by visual inspection and by quantitative comparison to controls, with and without partial volume correction. RESULTS All seven patients showed elevated FTP uptake in the anterior temporal lobe with a leftward asymmetry that was not observed in healthy controls. This elevated FTP signal, largely co-localised with atrophy, was evident on both visual inspection and quantitative cortical surface-based analysis. Five patients were amyloid negative, one was amyloid positive and one has an unknown amyloid status. CONCLUSIONS In this series of patients with clinical profiles, structural MRI and amyloid PET imaging typical for svPPA, FTP signal was unexpectedly elevated with a spatial pattern localised to areas of atrophy. This raises questions about the possible off-target binding of this tracer to non-tau molecules associated with neurodegeneration. Further investigation with autopsy analysis will help illuminate the binding target(s) of FTP in cases of suspected FTLD-TDP neuropathology.
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Affiliation(s)
- Sara J Makaretz
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA
| | - Megan Quimby
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA
| | - Jessica Collins
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA
| | - Nikos Makris
- Center for Morphometric Analysis, Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA
| | - Scott McGinnis
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA.,Center for Alzheimer Research and Treatment, Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Aaron Schultz
- Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA.,Alzheimer's Disease Research Center, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Neil Vasdev
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Keith A Johnson
- Center for Alzheimer Research and Treatment, Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Alzheimer's Disease Research Center, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Bradford C Dickerson
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA.,Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA.,Alzheimer's Disease Research Center, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
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114
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Lee BG, Leavitt MJ, Bernick CB, Leger GC, Rabinovici G, Banks SJ. A Systematic Review of Positron Emission Tomography of Tau, Amyloid Beta, and Neuroinflammation in Chronic Traumatic Encephalopathy: The Evidence To Date. J Neurotrauma 2018; 35:2015-2024. [PMID: 29609516 PMCID: PMC6421996 DOI: 10.1089/neu.2017.5558] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Chronic traumatic encephalopathy (CTE) is associated with pathological changes, yet detecting these changes during life has proven elusive. Positron emission tomography (PET) offers the potential for identifying such pathology. Few studies have been completed to date and their approaches and results have been diverse. It was the objective of this review to systematically examine relevant research using ligands for PET that bind to identified pathology in CTE. We focused on identification of patterns of binding and addressing gaps in knowledge of PET imaging for CTE. A comprehensive literature search was conducted. Data used were published on or before May 22, 2017. As the extant literature is limited, any peer-reviewed article assessing military, contact sports athletes, or professional fighters was considered for inclusion. The main outcomes were regional binding to brain regions identified through control comparisons or through clinical metrics (e.g., standardized uptake volume ratios). A total of 1207 papers were identified for review, of which six met inclusion criteria. Meta-analyses were planned but were deemed inappropriate given the small number of studies identified. Methodological concerns in these initial papers included small sample sizes, lack of a control comparison, use of nonstandard statistical procedures to quantify data, and interpretation of potentially off-target binding areas. Across studies, the hippocampi, amygdalae, and midbrain had reasonably consistent increased uptake. Evidence for increased uptake in cortical regions was less consistent. The evidence suggests that the field of PET imaging in those at risk for CTE remains nascent. As the field evolves to include more stringent studies, ligands for PET may prove an important tool in identifying CTE in vivo.
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Affiliation(s)
- Bern G. Lee
- Cleveland Clinic Lou Ruvo Center for Brain Health and Lerner College of Medicine, Las Vegas, Nevada
- University of Nevada, Las Vegas, Las Vegas, Nevada
| | - MacKenzie J. Leavitt
- Cleveland Clinic Lou Ruvo Center for Brain Health and Lerner College of Medicine, Las Vegas, Nevada
| | - Charles B. Bernick
- Cleveland Clinic Lou Ruvo Center for Brain Health and Lerner College of Medicine, Las Vegas, Nevada
| | - Gabriel C. Leger
- Cleveland Clinic Lou Ruvo Center for Brain Health and Lerner College of Medicine, Las Vegas, Nevada
| | - Gil Rabinovici
- Department of Neurology, Memory and Aging Center, University of California, San Francisco
| | - Sarah J. Banks
- Cleveland Clinic Lou Ruvo Center for Brain Health and Lerner College of Medicine, Las Vegas, Nevada
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115
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Harada R, Okamura N, Furumoto S, Yanai K. Imaging Protein Misfolding in the Brain Using β-Sheet Ligands. Front Neurosci 2018; 12:585. [PMID: 30186106 PMCID: PMC6110819 DOI: 10.3389/fnins.2018.00585] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 08/06/2018] [Indexed: 12/12/2022] Open
Abstract
Neurodegenerative diseases characterized by pathological protein accumulation in cells are termed “proteinopathies.” Although various protein aggregates share cross-β-sheet structures, actual conformations vary among each type of protein deposit. Recent progress in the development of radiotracers for positron emission tomography (PET) has enabled the visualization of protein aggregates in living brains. Amyloid PET tracers have been developed, and are widely used for the diagnosis of Alzheimer’s disease and non-invasive assessment of amyloid burden in clinical trials of anti-dementia drugs. Furthermore, several tau PET tracers have been successfully developed and used in the clinical studies. However, recent studies have identified the presence of off-target binding of radiotracers in areas of tau deposition, suggesting that concomitant neuroinflammatory changes might affect tracer binding. In contrast to amyloid and tau PET, there are no established tracers for imaging Lewy bodies in the human brain. In this review, we describe lessons learned from the development of PET tracers and discuss the future direction of tracer development for protein misfolding diseases.
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Affiliation(s)
- Ryuichi Harada
- Department of Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Nobuyuki Okamura
- Division of Pharmacology, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Shozo Furumoto
- Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan
| | - Kazuhiko Yanai
- Department of Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan.,Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan
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116
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Utianski RL, Whitwell JL, Schwarz CG, Duffy JR, Botha H, Clark HM, Machulda MM, Senjem ML, Knopman DS, Petersen RC, Jack CR, Lowe VJ, Josephs KA. Tau uptake in agrammatic primary progressive aphasia with and without apraxia of speech. Eur J Neurol 2018; 25:1352-1357. [PMID: 29935044 DOI: 10.1111/ene.13733] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 06/20/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND PURPOSE The non-fluent/agrammatic variant of primary progressive aphasia (agPPA) is a heterogeneous diagnosis wherein some individuals have apraxia of speech (AOS). When agPPA includes AOS, a tauopathy is the likely underlying pathology. Recently, [18F]AV-1451 was developed for the in-vivo assessment of tau. In this study, we compared patterns of tau tracer uptake in patients with agPPA with and without AOS. METHODS Nine patients with agPPA (four without AOS) underwent tau positron emission tomography imaging with [18F]AV-1451. Uptake of [18F]AV-1451 was assessed as cortical to cerebellar crus ratio (standard uptake value ratio) in cortical regions of interest measured using the MCALT atlas and compared voxel-wise in SPM12. Each patient was age- and sex-matched to three controls. RESULTS The agPPA without AOS showed uptake in the left frontal and temporal lobes, whereas agPPA with AOS showed uptake in the bilateral supplementary motor areas, frontal lobes, precuneus and precentral gyrus relative to controls. The left precentral gyrus had uptake in agPPA with AOS relative to those without AOS. CONCLUSIONS This cross-sectional study suggests that [18F]AV-1451 uptake in the precentral gyrus is implicated in AOS in agPPA.
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Affiliation(s)
- R L Utianski
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - J L Whitwell
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - C G Schwarz
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - J R Duffy
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - H Botha
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - H M Clark
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - M M Machulda
- Department of Psychiatry & Psychology, Mayo Clinic, Rochester, MN, USA
| | - M L Senjem
- Department of Radiology, Mayo Clinic, Rochester, MN, USA.,Department of Information Technology, Mayo Clinic, Rochester, MN, USA
| | - D S Knopman
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - R C Petersen
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - C R Jack
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - V J Lowe
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - K A Josephs
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
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117
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Okamura N, Harada R, Ishiki A, Kikuchi A, Nakamura T, Kudo Y. The development and validation of tau PET tracers: current status and future directions. Clin Transl Imaging 2018; 6:305-316. [PMID: 30148121 PMCID: PMC6096533 DOI: 10.1007/s40336-018-0290-y] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 07/03/2018] [Indexed: 01/02/2023]
Abstract
Purpose To provide an overview on positron emission tomography (PET) imaging of tau pathology in Alzheimer’s disease (AD) and other neurodegenerative disorders. Results Different classes of tau tracers such as flortaucipir, THK5317, and PBB3 have been developed and utilized in previous clinical studies. In AD, the topographical distribution of tracer binding follows the known distribution of neurofibrillary tangles and is closely associated with neurodegeneration as well as the clinical phenotype of dementia. Significant retention of tracers has also been observed in the frequent site of the 4-repeat (4R) tau isoform deposits in non-AD tauopathies, such as in progressive supranuclear palsy. However, in vitro binding studies indicate that most tau tracers are less sensitive to straight tau filaments, in contrast to their high binding affinity to paired helical filaments of tau (PHF-tau). The first-generation of tau tracers shows off-target binding in the basal ganglia, midbrain, thalamus, choroid plexus, and venous sinus. Off-target binding of THK5351 to monoamine oxidase B (MAO-B) has been observed in disease-associated brain regions linked to neurodegeneration and is associated with astrogliosis in areas of misfolded protein accumulation. The second generation of tau tracers, such as [18F]MK-6240, is highly selective to PHF-tau with little off-target binding and have enabled the reliable assessment of PHF-tau burden in aging and AD. Conclusions Tau PET tracers have enabled in vivo quantification of PHF-tau burden in human brains. Tau PET can help in understanding the underlying cause of dementia symptoms, and in patient selection for clinical trials of anti-dementia therapies.
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Affiliation(s)
- Nobuyuki Okamura
- 1Division of Pharmacology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan.,3Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Ryuichi Harada
- 2Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan
| | - Aiko Ishiki
- 3Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Akio Kikuchi
- 4Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
| | - Tadaho Nakamura
- 1Division of Pharmacology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Yukitsuka Kudo
- 3Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
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118
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Ishiki A, Harada R, Kai H, Sato N, Totsune T, Tomita N, Watanuki S, Hiraoka K, Ishikawa Y, Funaki Y, Iwata R, Furumoto S, Tashiro M, Sasano H, Kitamoto T, Kudo Y, Yanai K, Furukawa K, Okamura N, Arai H. Neuroimaging-pathological correlations of [ 18F]THK5351 PET in progressive supranuclear palsy. Acta Neuropathol Commun 2018; 6:53. [PMID: 29958546 PMCID: PMC6025736 DOI: 10.1186/s40478-018-0556-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 06/19/2018] [Indexed: 11/10/2022] Open
Abstract
Recent positron emission tomography (PET) studies have demonstrated the accumulation of tau PET tracer in the affected region of progressive supranuclear palsy (PSP) cases. To confirm the binding target of radiotracer in PSP, we performed an imaging-pathology correlation study in two autopsy-confirmed PSP patients who underwent [18F]THK5351 PET before death. One patient with PSP Richardson syndrome showed elevated tracer retention in the globus pallidus and midbrain. In a patient with PSP-progressive nonfluent aphasia, [18F]THK5351 retention also was observed in the cortical areas, particularly the temporal cortex. Neuropathological examination confirmed PSP in both patients. Regional [18F]THK5351 standardized uptake value ratio (SUVR) in antemortem PET was significantly correlated with monoamine oxidase-B (MAO-B) level, reactive astrocytes density, and tau pathology at postmortem examination. In in vitro autoradiography, specific THK5351 binding was detected in the area of antemortem [18F]THK5351 retention, and binding was blocked completely by a reversible selective MAO-B inhibitor, lazabemide, in brain samples from these patients. In conclusion, [18F]THK5351 PET signals reflect MAO-B expressing reactive astrocytes, which may be associated with tau accumulation in PSP.
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119
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Schaeverbeke J, Evenepoel C, Declercq L, Gabel S, Meersmans K, Bruffaerts R, Adamczuk K, Dries E, Van Bouwel K, Sieben A, Pijnenburg Y, Peeters R, Bormans G, Van Laere K, Koole M, Dupont P, Vandenberghe R. Distinct [ 18F]THK5351 binding patterns in primary progressive aphasia variants. Eur J Nucl Med Mol Imaging 2018; 45:2342-2357. [PMID: 29946950 PMCID: PMC6208807 DOI: 10.1007/s00259-018-4075-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/12/2018] [Indexed: 12/12/2022]
Abstract
PURPOSE To assess the binding of the PET tracer [18F]THK5351 in patients with different primary progressive aphasia (PPA) variants and its correlation with clinical deficits. The majority of patients with nonfluent variant (NFV) and logopenic variant (LV) PPA have underlying tauopathy of the frontotemporal lobar or Alzheimer disease type, respectively, while patients with the semantic variant (SV) have predominantly transactive response DNA binding protein 43-kDa pathology. METHODS The study included 20 PPA patients consecutively recruited through a memory clinic (12 NFV, 5 SV, 3 LV), and 20 healthy controls. All participants received an extensive neurolinguistic assessment, magnetic resonance imaging and amyloid biomarker tests. [18F]THK5351 binding patterns were assessed on standardized uptake value ratio (SUVR) images with the cerebellar grey matter as the reference using statistical parametric mapping. Whole-brain voxel-wise regression analysis was performed to evaluate the association between [18F]THK5351 SUVR images and neurolinguistic scores. Analyses were performed with and without partial volume correction. RESULTS Patients with NFV showed increased binding in the supplementary motor area, left premotor cortex, thalamus, basal ganglia and midbrain compared with controls and patients with SV. Patients with SV had increased binding in the temporal lobes bilaterally and in the right ventromedial frontal cortex compared with controls and patients with NFV. The whole-brain voxel-wise regression analysis revealed a correlation between agrammatism and motor speech impairment, and [18F]THK5351 binding in the left supplementary motor area and left postcentral gyrus. Analysis of [18F]THK5351 scans without partial volume correction revealed similar results. CONCLUSION [18F]THK5351 imaging shows a topography closely matching the anatomical distribution of predicted underlying pathology characteristic of NFV and SV PPA. [18F]THK5351 binding correlates with the severity of clinical impairment.
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Affiliation(s)
- Jolien Schaeverbeke
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Alzheimer Research Centre KU Leuven, Leuven Research Institute for Neuroscience & Disease, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Charlotte Evenepoel
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Alzheimer Research Centre KU Leuven, Leuven Research Institute for Neuroscience & Disease, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Lieven Declercq
- Laboratory of Radiopharmaceutical Research, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Nuclear Medicine and Molecular Imaging, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Silvy Gabel
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Alzheimer Research Centre KU Leuven, Leuven Research Institute for Neuroscience & Disease, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Karen Meersmans
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Rose Bruffaerts
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Neurology Department, University Hospitals Leuven, Herestraat 49, box 7003, 3000, Leuven, Belgium
| | - Kate Adamczuk
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Alzheimer Research Centre KU Leuven, Leuven Research Institute for Neuroscience & Disease, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Eva Dries
- Neurology Department, University Hospitals Leuven, Herestraat 49, box 7003, 3000, Leuven, Belgium
| | - Karen Van Bouwel
- Neurology Department, University Hospitals Leuven, Herestraat 49, box 7003, 3000, Leuven, Belgium
| | - Anne Sieben
- Neurodegenerative Brain Diseases Group, Center for Molecular Neurology, VIB, Universiteitsplein 1, 2610, Antwerp, Belgium.,Institute Born-Bunge, Neuropathology and Laboratory of Neurochemistry and Behavior, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.,Neurology Department, University Hospital Ghent, Corneel Heymanslaan 10, 9000, Ghent, Belgium
| | - Yolande Pijnenburg
- Old Age Psychiatry Department, GGZinGeest, Van Hilligaertstraat 21, 1072 JX, Amsterdam, The Netherlands.,Alzheimer Center & Department of Neurology, VU University Medical Center, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands
| | - Ronald Peeters
- Radiology Department, University Hospitals Leuven, Leuven, Belgium
| | - Guy Bormans
- Laboratory of Radiopharmaceutical Research, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Nuclear Medicine and Molecular Imaging, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Koen Van Laere
- Alzheimer Research Centre KU Leuven, Leuven Research Institute for Neuroscience & Disease, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Nuclear Medicine and Molecular Imaging, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Michel Koole
- Nuclear Medicine and Molecular Imaging, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Patrick Dupont
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Alzheimer Research Centre KU Leuven, Leuven Research Institute for Neuroscience & Disease, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Rik Vandenberghe
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49, 3000, Leuven, Belgium. .,Alzheimer Research Centre KU Leuven, Leuven Research Institute for Neuroscience & Disease, KU Leuven, Herestraat 49, 3000, Leuven, Belgium. .,Neurology Department, University Hospitals Leuven, Herestraat 49, box 7003, 3000, Leuven, Belgium.
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120
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Brendel M, Yousefi BH, Blume T, Herz M, Focke C, Deussing M, Peters F, Lindner S, von Ungern-Sternberg B, Drzezga A, Bartenstein P, Haass C, Okamura N, Herms J, Yakushev I, Rominger A. Comparison of 18F-T807 and 18F-THK5117 PET in a Mouse Model of Tau Pathology. Front Aging Neurosci 2018; 10:174. [PMID: 29930508 PMCID: PMC5999706 DOI: 10.3389/fnagi.2018.00174] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 05/22/2018] [Indexed: 11/16/2022] Open
Abstract
Positron-emission-tomography (PET) imaging of tau pathology has facilitated development of anti-tau therapies. While members of the arylquinoline and pyridoindole families have been the most frequently used tau radioligands so far, analyses of their comparative performance in vivo are scantly documented. Here, we conducted a head-to-head PET comparison of the arylquinoline 18FT807 and the pyridoindole 18FTHK5117 PET in a mouse model of tau pathology. PET recordings were obtained in groups of (N = 5–7) P301S and wild-type (WT) mice at 6 and 9 months of age. Volume-of-interest based analysis (standard-uptake-value ratio, SUVR) was used to calculate effect sizes (Cohen’s d) for each tracer and age. Statistical parametric mapping (SPM) was used to assess regional similarity (dice coefficient) of tracer binding alterations for the two tracers. Immunohistochemistry staining of neurofibrillary tangles was performed for validation ex vivo. Significantly elevated 18F-T807 binding in the brainstem of P301S mice was already evident at 6 months (+14%, p < 0.01, d = 1.64), and increased further at 9 months (+23%, p < 0.001, d = 2.70). 18F-THK5117 indicated weaker increases and effect sizes at 6 months (+5%, p < 0.05, d = 1.07) and 9 months (+10%, p < 0.001, d = 1.49). Regional similarity of binding of the two tracers was high (71%) at 9 months. 18F-T807 was more sensitive than 18F-THK5117 to tau pathology in this model, although both tracers present certain obstacles, which need to be considered in the design of longitudinal preclinical tau imaging studies.
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Affiliation(s)
- Matthias Brendel
- Department of Nuclear Medicine, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Behrooz H Yousefi
- Department of Nuclear Medicine, Technical University of Munich, Munich, Germany.,Neuroimaging Center, Technische Universität München, Munich, Germany
| | - Tanja Blume
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Michael Herz
- Department of Nuclear Medicine, Technical University of Munich, Munich, Germany
| | - Carola Focke
- Department of Nuclear Medicine, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Maximilian Deussing
- Department of Nuclear Medicine, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Finn Peters
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Simon Lindner
- Department of Nuclear Medicine, Ludwig-Maximilians-University of Munich, Munich, Germany
| | | | - Alexander Drzezga
- Department of Nuclear Medicine, University of Cologne, Cologne, Germany
| | - Peter Bartenstein
- Department of Nuclear Medicine, Ludwig-Maximilians-University of Munich, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Christian Haass
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.,Biomedical Center, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Nobuyuki Okamura
- Division of Pharmacology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Jochen Herms
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Igor Yakushev
- Department of Nuclear Medicine, Technical University of Munich, Munich, Germany.,Neuroimaging Center, Technische Universität München, Munich, Germany
| | - Axel Rominger
- Department of Nuclear Medicine, Ludwig-Maximilians-University of Munich, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
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121
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Large inter- and intra-case variability of first generation tau PET ligand binding in neurodegenerative dementias. Acta Neuropathol Commun 2018; 6:34. [PMID: 29716656 PMCID: PMC5928586 DOI: 10.1186/s40478-018-0535-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 04/14/2018] [Indexed: 12/03/2022] Open
Abstract
Imaging of pathological tau with positron emission tomography (PET) has the potential to allow early diagnosis of the dementias and monitoring of disease progression, including assessment of therapeutic interventions, in vivo. The first generation of tau PET tracers, including the carbazole flortaucipir and the 2-arylquinolines of the THK series, are now used in clinical research; however, concerns have been raised about off-target binding and low sensitivity. With the aim to determine the nature of tau pathology depicted by structurally distinct tau ligands we carried out a microscopic neuropathological evaluation in post-mortem human brain tissue of cases with primary and secondary tauopathies. Carbazole and 2-arylquinoline binding was only observed in cases with Alzheimer’s disease and one case with frontotemporal dementia and parkinsonism linked to chromosome 17 exhibiting a R406W MAPT mutation. In end stage Alzheimer’s disease cases, fluorescent imaging with the carbazole T726 and the 2-arylquinoline THK-5117 revealed high inter- and intra-case variability of tracer binding, and this was corroborated by quantitative phosphorimaging with the PET tracer [18F]THK-5117. Microscopic analysis of the pathological inclusions revealed that the fluorescent tracers preferentially bind to premature tau aggregates. Whilst T726 binding was limited to neuronal tau, THK-5117 additionally depicted neuritic tau. Neither tracer depicted tau in pre-symptomatic disease. Our results highlight limitations of the first generation of tau PET tracers, in particular lack of correlation between pathological tau load and tracer binding, limited sensitivity to tau in early disease, and high variability in tracer binding between and within cases. Concerns remain that these limitations may also affect the next generation tracers as they target the same high affinity binding site. Therefore, it is crucial to assess inter- and intra-subject correlation of tracer binding with pathological tau load in post-mortem tissue studies, and to rigorously assess novel tau PET tracers before translation into clinical studies.
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Gatchel JR, Donovan NJ, Locascio JJ, Schultz AP, Becker JA, Chhatwal J, Papp KV, Amariglio RE, Rentz DM, Blacker D, Sperling RA, Johnson KA, Marshall GA. Depressive Symptoms and Tau Accumulation in the Inferior Temporal Lobe and Entorhinal Cortex in Cognitively Normal Older Adults: A Pilot Study. J Alzheimers Dis 2018; 59:975-985. [PMID: 28697559 DOI: 10.3233/jad-170001] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Depressive symptoms are common in older adults and associated with increased morbidity and cognitive decline. These symptoms occur during preclinical and prodromal stages of Alzheimer's disease (AD), but their relationship to tau, one of the main AD proteinopathies, is poorly understood. OBJECTIVE The objective of this study was to investigate the cross-sectional association between depressive symptoms and cerebral tau [18F T807 (also known as 18F-AV-1451) tau positron emission tomography (PET) imaging] in cognitively normal (CN) older adults. METHODS We measured depressive symptoms using the Geriatric Depression Scale (GDS), and in vivo cerebral tau using T807 PET in 111 CN older adults. We employed general linear regression models to evaluate the relationship of GDS score regressed on entorhinal cortex (EC) or inferior temporal (IT) tau in separate backward elimination models. Other predictors included age, sex, and in secondary analyses, amyloid (Pittsburgh Compound B PET). RESULTS Higher GDS was significantly associated with greater IT tau (partial r = 0.188, p = 0.050) and marginally associated with greater EC tau (partial r = 0.183, p = 0.055). In additional analyses including both linear and quadratic age terms, we found a significant U-shaped relation of GDS to age (p = 0.001). CONCLUSIONS Results suggest that IT and EC tau are modestly associated with depressive symptoms in CN older adults. Findings suggest a link between depressive symptoms and tau-mediated neurodegeneration in a region vulnerable in AD. Future longitudinal studies examining the association of more severe depressive symptoms and cerebral tau accumulation are needed to substantiate this finding and to guide prevention and treatment in AD.
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Affiliation(s)
- Jennifer R Gatchel
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.,Division of Geriatric Psychiatry, McLean Hospital, Harvard Medical School, Belmont, MA, USA
| | - Nancy J Donovan
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.,Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Joseph J Locascio
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Aaron P Schultz
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - J Alex Becker
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Jasmeer Chhatwal
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Kathryn V Papp
- Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Rebecca E Amariglio
- Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Dorene M Rentz
- Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Deborah Blacker
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.,Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Reisa A Sperling
- Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Keith A Johnson
- Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.,Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Gad A Marshall
- Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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Smith R, Schöll M, Londos E, Ohlsson T, Hansson O. 18F-AV-1451 in Parkinson's Disease with and without dementia and in Dementia with Lewy Bodies. Sci Rep 2018; 8:4717. [PMID: 29549278 PMCID: PMC5856779 DOI: 10.1038/s41598-018-23041-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 03/05/2018] [Indexed: 01/08/2023] Open
Abstract
Mixed pathologies of α-synuclein, β-amyloid and tau are relatively common in Parkinson’s disease (PD) and Dementia with Lewy Bodies (DLB). We therefore wanted to study the retention patterns of 18F-AV-1451 in PD, PD-dementia (PDD), and DLB. To do this 44 healthy controls, 11 non-demented patients with PD, 18 patients with PDD, and six patients with DLB underwent MRI and 18F-AV-1451 PET scanning and cognitive testing. We found that parietal 18F-AV-1451 retention was increased in patients with DLB compared to controls and PD patients, while 18F-AV-1451 uptake was reduced in the substantia nigra in PDD. Increased parietal 18F-AV-1451 PET uptake was associated with impaired performance on verbal fluency tests, and the decreased uptake in the substantia nigra correlated with worse motor function. We found no effect of the monoamine oxidase B inhibitor rasagiline on 18F-AV-1451 binding. In conclusion DLB patients have increased parietal 18F-AV-1451 uptake. Increased parietal tau is associated with executive impairment in patients with synucleinopathies, while decreased uptake in the substantia nigra is associated with parkinsonism. Further, our data indicate that 18F-AV-1451 does not significantly bind to MAO-B in vivo.
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Affiliation(s)
- Ruben Smith
- Department of Neurology, Skåne University Hospital, Lund, Sweden. .,Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.
| | - Michael Schöll
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Gothenburg, Sweden
| | - Elisabet Londos
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Memory Clinic, Skåne University Hospital, Malmö, Sweden
| | - Tomas Ohlsson
- Department of Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Oskar Hansson
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden. .,Memory Clinic, Skåne University Hospital, Malmö, Sweden.
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Jones DT, Knopman DS, Graff-Radford J, Syrjanen JA, Senjem ML, Schwarz CG, Dheel C, Wszolek Z, Rademakers R, Kantarci K, Petersen RC, Jack CR, Lowe VJ, Boeve BF. In vivo 18F-AV-1451 tau PET signal in MAPT mutation carriers varies by expected tau isoforms. Neurology 2018; 90:e947-e954. [PMID: 29440563 PMCID: PMC5858948 DOI: 10.1212/wnl.0000000000005117] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 12/05/2017] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To evaluate 18F-AV-1451 tau PET binding among microtubule-associated protein tau (MAPT) mutation carriers. METHODS Using a case-control study, we quantitatively and qualitatively compared tau PET scans in 10 symptomatic and 3 asymptomatic MAPT mutation carriers (n = 13, age range 42-67 years) with clinically normal (CN) participants (n = 241, age range 42-67 years) and an Alzheimer disease (AD) dementia cohort (n = 30, age range 52-67 years). Eight participants had MAPT mutations that involved exon 10 (N279K n = 5, S305N n = 2, P301L n = 1) and tend to form 4R tau pathology, and 5 had mutations outside exon 10 (V337M n = 2, R406W n = 3) and tend to form mixed 3R/4R tau pathology. RESULTS Tau PET signal was qualitatively and quantitatively different between participants with AD, CN participants, and MAPT mutation carriers, with the greatest signal intensity in those with AD and minimal regional signal in MAPT mutation carries with mutations in exon 10. However, MAPT mutation carriers with mutations outside exon 10 had uptake levels within the AD range, which was significantly higher than both MAPT mutation carriers with mutations in exon 10 and controls. CONCLUSIONS Tau PET shows higher magnitude of binding in MAPT mutation carriers who harbor mutations that are more likely to produce AD-like tau pathology (e.g., in our series, the non-exon 10 families tend to accumulate mixed 3R/4R aggregates). Exon 10 splicing determines the balance of 3R and 4R tau isoforms, with some mutations involving exon 10 predisposing to a greater proportion of 4R aggregates and consequently a lower level of AV-1451 binding, as seen in this case series, thus supporting the notion that this tau PET ligand has specific binding properties for AD-like tau pathology.
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Affiliation(s)
- David T Jones
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL.
| | - David S Knopman
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Jonathan Graff-Radford
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Jeremy A Syrjanen
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Matthew L Senjem
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Christopher G Schwarz
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Christina Dheel
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Zbigniew Wszolek
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Rosa Rademakers
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Kejal Kantarci
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Ronald C Petersen
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Clifford R Jack
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Val J Lowe
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
| | - Bradley F Boeve
- From the Departments of Neurology (D.T.J., D.S.K., J.G.-R., C.D., R.C.P., B.F.B.), Radiology (D.T.J., C.G.S., K.K., C.R.J., V.J.L.), Health Sciences Research (J.A.S.), and Information Technology (M.L.S.), Mayo Clinic, Rochester, MN; and Departments of Neurology (Z.W.) and Neuroscience (R.R.), Mayo Clinic, Jacksonville, FL
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McMillan CT, Huey ED. Flortaucipir imaging of MAPT: Mutations emphasize challenges for tau-targeted trials. Neurology 2018; 90:495-496. [PMID: 29440565 DOI: 10.1212/wnl.0000000000005112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Corey T McMillan
- From the Department of Neurology (C.T.M.), Penn Frontotemporal Degeneration Center, University of Pennsylvania, Philadelphia; and Departments of Psychiatry and Neurology (E.D.H.), Taub Institute for Research on Alzheimer's Disease and Aging, Columbia University, New York, NY.
| | - Edward D Huey
- From the Department of Neurology (C.T.M.), Penn Frontotemporal Degeneration Center, University of Pennsylvania, Philadelphia; and Departments of Psychiatry and Neurology (E.D.H.), Taub Institute for Research on Alzheimer's Disease and Aging, Columbia University, New York, NY
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126
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Josephs KA, Martin PR, Botha H, Schwarz CG, Duffy JR, Clark HM, Machulda MM, Graff-Radford J, Weigand SD, Senjem ML, Utianski RL, Drubach DA, Boeve BF, Jones DT, Knopman DS, Petersen RC, Jack CR, Lowe VJ, Whitwell JL. [ 18 F]AV-1451 tau-PET and primary progressive aphasia. Ann Neurol 2018; 83:599-611. [PMID: 29451323 PMCID: PMC5896771 DOI: 10.1002/ana.25183] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 02/12/2018] [Accepted: 02/13/2018] [Indexed: 12/14/2022]
Abstract
OBJECTIVES To assess [18 F]AV-1451 tau-PET (positron emission tomography) uptake patterns across the primary progressive aphasia (PPA) variants (logopenic, semantic, and agrammatic), examine regional uptake patterns of [18 F]AV-1451 independent of clinical diagnosis, and compare the diagnostic utility of [18 F]AV-1451, [18 F]-fluorodeoxygluclose (FDG)-PET and MRI (magnetic resonance imaging) to differentiate the PPA variants. METHODS We performed statistical parametric mapping of [18 F]AV-1451 across 40 PPA patients (logopenic-PPA = 14, semantic-PPA = 13, and agrammatic-PPA = 13) compared to 80 cognitively normal, Pittsburgh compound B-negative controls, age and gender matched 2:1. Principal component analysis of regional [18 F]AV-1451 tau-PET standard uptake value ratio was performed to understand underlying patterns of [18 F]AV-1451 uptake independent of clinical diagnosis. Penalized multinomial regression analyses were utilized to assess diagnostic utility. RESULTS Logopenic-PPA showed striking uptake throughout neocortex, particularly temporoparietal, compared to controls, semantic-PPA, and agrammatic-PPA. Semantic-PPA and agrammatic-PPA showed milder patterns of focal [18 F]AV-1451 uptake. Semantic-PPA showed elevated uptake (left>right) in anteromedial temporal lobes, compared to controls and agrammatic-PPA. Agrammatic-PPA showed elevated uptake (left>right) throughout prefrontal white matter and in subcortical gray matter structures, compared to controls and semantic-PPA. The principal component analysis of regional [18 F]AV-1451 indicated two primary dimensions, a severity dimension that distinguished logopenic-PPA from agrammatic-PPA and semantic-PPA, and a frontal versus temporal contrast that distinguishes agrammatic-PPA and semantic-PPA cases. Diagnostic utility of [18 F]AV-1451was superior to MRI and at least equal to FDG-PET. INTERPRETATION [18 F]AV-1451binding characteristics differ across the PPA variants and were excellent at distinguishing between the variants. [18 F]AV-1451binding characteristics were as good or better than other brain imaging modalities utilized in clinical practice, suggesting that [18 F]AV-1451 may have clinical diagnostic utility in PPA. Ann Neurol 2018 Ann Neurol 2018;83:599-611.
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Affiliation(s)
- Keith A. Josephs
- Department of Neurology (Behavioral Neurology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Peter R. Martin
- Department of Health Science Research (Biostatistics), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Hugo Botha
- Department of Neurology (Behavioral Neurology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | | | - Joseph R. Duffy
- Department of Neurology (Speech pathology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Heather M. Clark
- Department of Neurology (Speech pathology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Mary M. Machulda
- Department of Psychiatry (Neuropsychology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Jonathan Graff-Radford
- Department of Neurology (Behavioral Neurology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Stephen D. Weigand
- Department of Health Science Research (Biostatistics), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Matthew L. Senjem
- Department of Information Technology, Mayo Clinic, Rochester, Minnesota, U.S.A
- Department of Radiology (Neuroradiology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Rene L. Utianski
- Department of Neurology (Speech pathology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Daniel A. Drubach
- Department of Neurology (Behavioral Neurology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Bradley F. Boeve
- Department of Neurology (Behavioral Neurology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - David T. Jones
- Department of Neurology (Behavioral Neurology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - David S. Knopman
- Department of Neurology (Behavioral Neurology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Ronald C. Petersen
- Department of Neurology (Behavioral Neurology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Clifford R. Jack
- Department of Radiology (Neuroradiology), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Val J. Lowe
- Department of Radiology (Nuclear Medicine), Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Jennifer L. Whitwell
- Department of Radiology (Neuroradiology), Mayo Clinic, Rochester, Minnesota, U.S.A
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Lemoine L, Leuzy A, Chiotis K, Rodriguez-Vieitez E, Nordberg A. Tau positron emission tomography imaging in tauopathies: The added hurdle of off-target binding. ALZHEIMER'S & DEMENTIA: DIAGNOSIS, ASSESSMENT & DISEASE MONITORING 2018; 10:232-236. [PMID: 29780868 PMCID: PMC5956931 DOI: 10.1016/j.dadm.2018.01.007] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Ligands targeting tau for use with positron emission tomography have rapidly been developed during the past several years, enabling the in vivo study of tau pathology in patients with Alzheimer's disease and related non-Alzheimer's disease tauopathies. Several candidate compounds have been developed, showing good in vitro characteristics with respect to their ability to bind tau deposits; off-target binding, however, has also been observed. In this short commentary, we briefly summarize the available in vivo and in vitro evidence pertaining to their off-target binding and discuss the different approaches that are needed for the future development of tau positron emission tomography tracers.
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Affiliation(s)
- Laetitia Lemoine
- Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden
- Corresponding author. Tel.: +46 8 524 83 527; Fax: +46 8 585 85470 .
| | - Antoine Leuzy
- Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden
| | - Konstantinos Chiotis
- Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden
| | - Elena Rodriguez-Vieitez
- Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden
| | - Agneta Nordberg
- Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden
- Theme Aging, Karolinska University Hospital, Huddinge, Sweden
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Cho H, Seo SW, Choi JY, Lee HS, Ryu YH, Lee MS, Na DL, Kim HJ, Lyoo CH. Predominant subcortical accumulation of 18F-flortaucipir binding in behavioral variant frontotemporal dementia. Neurobiol Aging 2018; 66:112-121. [PMID: 29554554 DOI: 10.1016/j.neurobiolaging.2018.02.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 02/13/2018] [Accepted: 02/15/2018] [Indexed: 11/28/2022]
Abstract
Behavioral variant frontotemporal dementia (bvFTD) is the most common form of frontotemporal dementia, and tau pathology can be found in 40%-50% of bvFTD patients. In this study, we sought to investigate 18F-flortaucipir-binding patterns and their correlates in clinically diagnosed bvFTD patients by comparing with results for Alzheimer's disease (AD) patients. We enrolled 20 bvFTD, 20 AD, and 20 age-matched healthy subjects who underwent neuropsychological tests, magnetic resonance imaging, and tau positron emission tomography scans with 18F-flortaucipir. Regional standardized uptake value ratios for the cerebral cortex and underlying white matter were compared between the 2 groups. The bvFTD patients showed increased 18F-flortaucipir binding in the putamen and globus pallidus when compared to the healthy controls. In addition, bvFTD was associated with increased binding in the white matter regions underlying the frontal, anterior cingulate, and insula cortices. The bvFTD patients may exhibit predominantly subcortical 18F-flortaucipir-binding pattern that is distinct from the patterns seen in AD patients. We hypothesize that the clinical characteristics of bvFTD patients may be attributable to the dysfunctional frontal-subcortical networks. However, concerns remain regarding unknown "off-target" binding in the white matter and the basal ganglia.
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Affiliation(s)
- Hanna Cho
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sang Won Seo
- Departments of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jae Yong Choi
- Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea; Division of RI-Convergence Research, Korea Institute Radiological and Medical Sciences, Seoul, South Korea
| | - Hye Sun Lee
- Biostatistics Collaboration Unit, Yonsei University College of Medicine, Seoul, South Korea
| | - Young Hoon Ryu
- Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Myung Sik Lee
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Duk L Na
- Departments of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hee Jin Kim
- Departments of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
| | - Chul Hyoung Lyoo
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
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129
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Abstract
PURPOSE OF REVIEW Progressive supranuclear palsy (PSP) is a 4R tau neuropathologic entity. While historically defined by the presence of a vertical supranuclear gaze palsy and falls in the first symptomatic year, clinicopathologic studies identify alternate presenting phenotypes. This article reviews the new PSP diagnostic criteria, diagnostic approaches, and treatment strategies. RECENT FINDINGS The 2017 International Parkinson and Movement Disorder Society PSP criteria outline 14 core clinical features and 4 clinical clues that combine to diagnose one of eight PSP phenotypes with probable, possible, or suggestive certainty. Evidence supports the use of select imaging approaches in the classic PSP-Richardson syndrome phenotype. Recent trials of putative disease-modifying agents showed no benefit. The new PSP diagnostic criteria incorporating the range of presenting phenotypes have important implications for diagnosis and research. More work is needed to understand how diagnostic evaluations inform phenotype assessment and identify expected progression. Current treatment is symptomatic, but tau-based therapeutics are in active clinical trials.
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130
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Villemagne VL, Doré V, Burnham SC, Masters CL, Rowe CC. Imaging tau and amyloid-β proteinopathies in Alzheimer disease and other conditions. Nat Rev Neurol 2018; 14:225-236. [DOI: 10.1038/nrneurol.2018.9] [Citation(s) in RCA: 230] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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131
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Goedert M, Yamaguchi Y, Mishra SK, Higuchi M, Sahara N. Tau Filaments and the Development of Positron Emission Tomography Tracers. Front Neurol 2018; 9:70. [PMID: 29497399 PMCID: PMC5818396 DOI: 10.3389/fneur.2018.00070] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 01/30/2018] [Indexed: 12/15/2022] Open
Abstract
A pathological pathway leading from soluble, monomeric to insoluble, filamentous Tau, is believed to underlie human Tauopathies. Cases of frontotemporal dementia are caused by dominantly inherited mutations in MAPT, the Tau gene. They show that dysfunction of Tau protein is sufficient to cause neurodegeneration and dementia. Extrapolation to the more common sporadic Tauopathies leads one to conclude that the pathological pathway is central to the development of all cases of disease, even if there are multiple reasons for Tau assembly. These findings are conceptually similar to those reported for beta-amyloid, alpha-synuclein and prion protein. Here, we provide an overview of Tau filaments and their positron emission tomography ligands.
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Affiliation(s)
- Michel Goedert
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | | | | | - Makoto Higuchi
- National Institute of Radiological Sciences, Chiba, Japan
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132
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Klunk WE. Molecular imaging: What is right and what is an illusion? ALZHEIMER'S & DEMENTIA: DIAGNOSIS, ASSESSMENT & DISEASE MONITORING 2018; 10:217-220. [PMID: 29780866 PMCID: PMC5956935 DOI: 10.1016/j.dadm.2018.01.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Over the past 40 years, brain molecular imaging has evolved from measuring cerebral metabolism with fluorodeoxyglucose, to neuroreceptor imaging, to imaging pathological protein deposits. In the early going, the characteristics of successful molecular imaging radiotracers were defined, and a detailed “Process” was developed for the collection of basic pharmacodynamic and pharmacokinetic data. These data are essential for the interpretation of in vivo imaging data and for defining the strengths, weaknesses, and limitations of new tracers. This perspective discusses the use of this “Process” in the development of the amyloid β positron emission tomography radiotracer, Pittsburgh Compound-B, and discusses some of the current controversies and difficulties in the field of tau positron emission tomography in the context of human data that preceded completion of this radiotracer characterization process—which still remains to be completed. As a field, we must decide which data are valid and which are artifacts and determine that when the artifacts are so overwhelming, the data are merely an illusion.
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133
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Ni R, Ji B, Ono M, Sahara N, Zhang MR, Aoki I, Nordberg A, Suhara T, Higuchi M. Comparative In Vitro and In Vivo Quantifications of Pathologic Tau Deposits and Their Association with Neurodegeneration in Tauopathy Mouse Models. J Nucl Med 2018; 59:960-966. [PMID: 29419480 DOI: 10.2967/jnumed.117.201632] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 01/09/2018] [Indexed: 11/16/2022] Open
Abstract
Fibrillary tau aggregates in Alzheimer disease and allied neurodegenerative disorders have been visualized in vivo by PET, whereas mechanistic links between PET-detectable tau deposits and neurotoxicity remain elusive. Here, we took advantage of transgenic mouse models of tauopathies to evaluate associations between PET and postmortem measures of tau probe binding and their relation to neuronal loss. Methods: PET with a tau probe, 11C-PBB3 (2-((1E,3E)-4-(6-(11C-methylamino)pyridine-3-yl)buta-1,3-dienyl)benzo[d]thiazol-6-ol), and volumetric MRI were performed for transgenic rTg4510 mice and nontransgenic mice. Binding of 11C-PBB3 and its blockade by another tau binding compound, AV-1451 (-(6-fluoropyridine-3-yl)-5H-pyrido[4,3-b]indole), in homogenized brains of tauopathy patients and rTg4510 and PS19 mice were quantified, and 11C-PBB3-positive and phosphorylated tau lesions in sectioned brains of these mice were assessed. Results: In vivo 11C-PBB3 binding to the rTg4510 neocortex/hippocampus was increased relative to controls and correlated with local atrophy. In vitro 11C-PBB3 binding in the neocortex/hippocampus also correlated well with in vivo radioligand binding and regional atrophy in the same individual rTg4510 mice. By contrast, in vitro 11C-PBB3 binding was elevated in the brain stem but not hippocampus of PS19 mice, despite a pronounced loss of neurons in the hippocampus rather than brain stem. Finally, 11C-PBB3 and AV-1451 showed similar binding properties between mouse models and tauopathy patients. Conclusion: The present findings support the distinct utilities of 11C-PBB3 PET and MRI in rTg4510 and PS19 mice for quantitatively pursuing mechanisms connecting PET-detectable and PET-undetectable tau aggregations to neuronal death, which recapitulate 2 different modes of tau-provoked neurotoxicity.
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Affiliation(s)
- Ruiqing Ni
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Chiba 263-8555, Japan.,Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics, Karolinska Institute, Stockholm, Sweden; and.,Theme Aging, Karolinska University Hospital, Stockholm, Sweden
| | - Bin Ji
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Chiba 263-8555, Japan
| | - Maiko Ono
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Chiba 263-8555, Japan
| | - Naruhiko Sahara
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Chiba 263-8555, Japan
| | - Ming-Rong Zhang
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Chiba 263-8555, Japan
| | - Ichio Aoki
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Chiba 263-8555, Japan
| | - Agneta Nordberg
- Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics, Karolinska Institute, Stockholm, Sweden; and.,Theme Aging, Karolinska University Hospital, Stockholm, Sweden
| | - Tetsuya Suhara
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Chiba 263-8555, Japan
| | - Makoto Higuchi
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Chiba 263-8555, Japan
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134
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Lyoo CH, Cho H, Choi JY, Ryu YH, Lee MS. Tau Positron Emission Tomography Imaging in Degenerative Parkinsonisms. J Mov Disord 2018; 11:1-12. [PMID: 29381890 PMCID: PMC5790630 DOI: 10.14802/jmd.17071] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 11/20/2017] [Indexed: 01/08/2023] Open
Abstract
In recent years, several radiotracers that selectively bind to pathological tau proteins have been developed. Evidence is emerging that binding patterns of in vivo tau positron emission tomography (PET) studies in Alzheimer’s disease (AD) patients closely resemble the distribution patterns of known neurofibrillary tangle pathology, with the extent of tracer binding reflecting the clinical and pathological progression of AD. In Lewy body diseases (LBD), tau PET imaging has clearly revealed cortical tau burden with a distribution pattern distinct from AD and increased cortical binding within the LBD spectrum. In progressive supranuclear palsy, the globus pallidus and midbrain have shown increased binding most prominently. Tau PET patterns in patients with corticobasal syndrome are characterized by asymmetrical uptake in the motor cortex and underlying white matter, as well as in the basal ganglia. Even in the patients with multiple system atrophy, which is basically a synucleinopathy, 18F-flortaucipir, a widely used tau PET tracer, also binds to the atrophic posterior putamen, possibly due to off-target binding. These distinct patterns of tau-selective radiotracer binding in the various degenerative parkinsonisms suggest its utility as a potential imaging biomarker for the differential diagnosis of parkinsonisms.
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Affiliation(s)
- Chul Hyoung Lyoo
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Hanna Cho
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Jae Yong Choi
- Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.,Division of RI-Convergence Research, Korea Institute Radiological and Medical Sciences, Seoul, Korea
| | - Young Hoon Ryu
- Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Myung Sik Lee
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
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135
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Tau-PET imaging with [18F]AV-1451 in primary progressive apraxia of speech. Cortex 2018; 99:358-374. [PMID: 29353121 DOI: 10.1016/j.cortex.2017.12.021] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 10/24/2017] [Accepted: 12/15/2017] [Indexed: 12/12/2022]
Abstract
Apraxia of speech is a motor speech disorder characterized by combinations of slow speaking rate, abnormal prosody, distorted sound substitutions, and trial-and-error articulatory movements. Apraxia of speech is due to abnormal planning and/or programming of speech production. It is referred to as primary progressive apraxia of speech (PPAOS) when it is the only symptom of a neurodegenerative condition. Past reports suggest an association of PPAOS with primary 4-repeat (4R) tau (e.g., progressive supranuclear palsy, corticobasal degeneration), rather than amyloid, pathology. The goal of the current study was to investigate the distribution of tau tracer uptake using [18F]AV-1451 positron emission tomography (PET) imaging in patients with PPAOS. Fourteen PPAOS patients underwent [18F]AV-1451 PET (tau-PET) imaging, [C11] Pittsburgh Compound B (PiB) PET and structural MRI and were matched 3:1 by age and sex to 42 cognitively normal controls. Tau-PET uptake was assessed at the region-of-interest (ROI) level and at the voxel-level. The PPAOS group (n = 14) showed increased tau-PET uptake in the precentral gyrus, supplementary motor area and Broca's area compared to controls. To examine whether tau deposition in Broca's area was related to the presence of aphasia, we examined a subgroup of the PPAOS patients who had predominant apraxia of speech, with concomitant aphasia (PPAOSa; n = 7). The PPAOSa patients showed tau-PET uptake in the same regions as the whole group. However, the remaining seven patients who did not have aphasia showed uptake only in superior premotor and precentral cortices, with no uptake observed in Broca's area. This cross-sectional study demonstrates that elevated tau tracer uptake is observed using [18F]AV-1451 in PPAOS. Further, it appears that [18F]AV-1451 is sensitive to the regional distribution of tau deposition in different stages of PPAOS, given the relationship between tau signal in Broca's area and the presence of aphasia.
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136
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Chen ST, Siddarth P, Merrill DA, Martinez J, Emerson ND, Liu J, Wong KP, Satyamurthy N, Giza CC, Huang SC, Fitzsimmons RP, Bailes J, Omalu B, Barrio JR, Small GW. FDDNP-PET Tau Brain Protein Binding Patterns in Military Personnel with Suspected Chronic Traumatic Encephalopathy1. J Alzheimers Dis 2018; 65:79-88. [PMID: 30040711 PMCID: PMC6728605 DOI: 10.3233/jad-171152] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Our group has shown that in vivo tau brain binding patterns from FDDNP-PET scans in retired professional football players with suspected chronic traumatic encephalopathy differ from those of tau and amyloid aggregate binding observed in Alzheimer's disease (AD) patients and cognitively-intact controls. OBJECTIVE To compare these findings with those from military personnel with histories of mild traumatic brain injury(mTBI). METHODS FDDNP-PET brain scans were compared among 7 military personnel and 15 retired players with mTBI histories and cognitive and/or mood symptoms, 24 AD patients, and 28 cognitively-intact controls. Nonparametric ANCOVAs with Tukey-Kramer adjusted post-hoc comparisons were used to test for significant differences in regional FDDNP binding among subject groups. RESULTS FDDNP brain binding was higher in military personnel compared to controls in the amygdala, midbrain, thalamus, pons, frontal and anterior and posterior cingulate regions (p < 0.01-0.0001). Binding patterns in the military personnel were similar to those of the players except for the amygdala and striatum (binding higher in players; p = 0.02-0.003). Compared with the AD group, the military personnel showed higher binding in the midbrain (p = 0.0008) and pons (p = 0.002) and lower binding in the medial temporal, lateral temporal, and parietal regions (all p = 0.02). CONCLUSION This first study of in vivo tau and amyloid brain signals in military personnel with histories of mTBI shows binding patterns similar to those of retired football players and distinct from the binding patterns in AD and normal aging, suggesting the potential value of FDDNP-PET for early detection and treatment monitoring in varied at-risk populations.
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Affiliation(s)
- Stephen T. Chen
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - Prabha Siddarth
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA
- UCLA Longevity Center at the Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA
| | - David A. Merrill
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA
- UCLA Longevity Center at the Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA
| | - Jacqueline Martinez
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA
- UCLA Longevity Center at the Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA
| | - Natacha D. Emerson
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA
- UCLA Longevity Center at the Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA
| | - Jie Liu
- Department of Medical and Molecular Pharmacology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Koon-Pong Wong
- Department of Medical and Molecular Pharmacology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Nagichettiar Satyamurthy
- Department of Medical and Molecular Pharmacology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Christopher C. Giza
- Department of Neurosurgery at the David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Sung-Cheng Huang
- Department of Medical and Molecular Pharmacology, University of California, Los Angeles, Los Angeles, CA, USA
| | | | - Julian Bailes
- Department of Neurosurgery, North Shore University Health System and University of Chicago Pritzker School of Medicine, Evanston, IL, USA
| | - Bennet Omalu
- Department of Medical Pathology and Laboratory Medicine, School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - Jorge R. Barrio
- Department of Medical and Molecular Pharmacology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Gary W. Small
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA
- UCLA Longevity Center at the Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA
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137
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Abstract
Background Positron emission tomography ligands are now available that bind to tau proteins in the brain, providing the exciting opportunity to assess the presence and distribution of tau in vivo in living patients. Methods This manuscript performed a systematic review of studies that have performed tau PET imaging in patients with parkinsonian disorders. Pubmed was searched up to November 2017, and the review included case reports and patient-control studies. Results Most tau-PET studies have utilized the [18F]AV-1451 ligand, with a few using the [11C]PBB3 and [18F]THK-5351 ligands. Elevated cortical tau-PET uptake has been observed in Parkinson's disease dementia and dementia with Lewy bodies, presumed to be related to Alzheimer's disease-related pathology. Mild patterns of tau-PET uptake have been observed in subcortical structures in progressive supranuclear palsy and subcortical structures and motor cortex in corticobasal syndrome, although discrepancy with autoradiographic studies that show lack of binding to 4-repeat tau and "off-target" binding observed in subcortical structures limits interpretation of these findings. Findings in frontotemporal dementia with tau mutations are variable, but elevated signal is most pronounced in mutations with deposition of both 3 and 4-repeat tau. Elevated tau-PET uptake has also been observed in multiple system atrophy, a synucleinopathy. Conclusion The value of the current generation of tau-PET ligands varies across Parkinsonian syndromes depending upon underlying variability in tau pathology and "off-target" binding. More work is needed to understand the biological basis of binding and more specific tau PET ligands are needed to study parkinsonian disorders.
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138
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Vermeiren C, Motte P, Viot D, Mairet-Coello G, Courade JP, Citron M, Mercier J, Hannestad J, Gillard M. The tau positron-emission tomography tracer AV-1451 binds with similar affinities to tau fibrils and monoamine oxidases. Mov Disord 2017; 33:273-281. [DOI: 10.1002/mds.27271] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 11/01/2017] [Accepted: 11/22/2017] [Indexed: 12/25/2022] Open
Affiliation(s)
| | - Philippe Motte
- UCB BioPharma sprl, Chemin du Foriest; Braine l'Alleud Belgium
| | - Delphine Viot
- UCB BioPharma sprl, Chemin du Foriest; Braine l'Alleud Belgium
| | | | | | - Martin Citron
- UCB BioPharma sprl, Chemin du Foriest; Braine l'Alleud Belgium
| | - Joël Mercier
- UCB BioPharma sprl, Chemin du Foriest; Braine l'Alleud Belgium
| | - Jonas Hannestad
- Denali Therapeutics Inc.; South San Francisco California USA
| | - Michel Gillard
- UCB BioPharma sprl, Chemin du Foriest; Braine l'Alleud Belgium
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139
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Abstract
Currently, the differential diagnosis between atypical parkinsonisms and classical idiopathic Parkinson's disease can be quite difficult because of the significant overlap of clinical presentation and symptoms. Neurodegenerative conditions, including progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and frontotemporal dementia (FTD), are primarily characterized by accumulation of tau protein in the brain. Recent imaging developments for tau pathology may provide a promising tool for the assessment of diagnosis, prognosis, and progression of these neurodegenerative disorders. This review will survey PET studies to describe the recent advances in the imaging of tau pathology in PSP, CBD, and FTD.
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Affiliation(s)
- Mikaeel Valli
- a Research Imaging Centre , Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto , Toronto , ON , Canada.,b Division of Brain, Imaging and Behaviour-Systems Neuroscience , Krembil Research Institute, UHN, University of Toronto , Toronto , ON , Canada.,c Institute of Medical Science , University of Toronto , Toronto , ON , Canada
| | - Antonio P Strafella
- a Research Imaging Centre , Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto , Toronto , ON , Canada.,b Division of Brain, Imaging and Behaviour-Systems Neuroscience , Krembil Research Institute, UHN, University of Toronto , Toronto , ON , Canada.,c Institute of Medical Science , University of Toronto , Toronto , ON , Canada.,d Morton and Gloria Shulman Movement Disorder Unit & E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine , Toronto Western Hospital, UHN, University of Toronto , Toronto , ON , Canada
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140
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Jang YK, Lyoo CH, Park S, Oh SJ, Cho H, Oh M, Ryu YH, Choi JY, Rabinovici GD, Kim HJ, Moon SH, Jang H, Lee JS, Jagust WJ, Na DL, Kim JS, Seo SW. Head to head comparison of [ 18F] AV-1451 and [ 18F] THK5351 for tau imaging in Alzheimer's disease and frontotemporal dementia. Eur J Nucl Med Mol Imaging 2017; 45:432-442. [PMID: 29143870 DOI: 10.1007/s00259-017-3876-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 11/03/2017] [Indexed: 11/25/2022]
Abstract
PURPOSE Tau accumulation is a core pathologic change in various neurodegenerative diseases including Alzheimer's disease and frontotemporal lobar degeneration-tau. Recently, tau positron emission tomography tracers such as [18F] AV-1451 and [18F] THK5351 have been developed to detect tau deposition in vivo. In the present study, we performed a head to head comparison of these two tracers in Alzheimer's disease and frontotemporal dementia cases and aimed to investigate which tracers are better suited to image tau in these disorders. METHODS A cross-sectional study was conducted using a hospital-based sample at a tertiary referral center. We recruited eight participants (two Alzheimer's disease, four frontotemporal dementia and two normal controls) who underwent magnetic resonance image, amyloid positron emission tomography with [18F]-Florbetaben and tau positron emission tomography with both THK5351 and AV-1451. To measure regional AV1451 and THK5351 uptakes, we used the standardized uptake value ratios by dividing mean activity in target volume of interest by mean activity in the cerebellar hemispheric gray matter. RESULTS Although THK5351 and AV-1451 uptakes were highly correlated, cortical uptake of AV-1451 was more striking in Alzheimer's disease, while cortical uptake of THK5351 was more prominent in frontotemporal dementia. THK5351 showed higher off-target binding than AV-1451 in the white matter, midbrain, thalamus, and basal ganglia. CONCLUSIONS AV-1451 is more sensitive and specific to Alzheimer's disease type tau and shows lower off-target binding, while THK5351 may mirror non-specific neurodegeneration.
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Affiliation(s)
- Young Kyoung Jang
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Kangnam-ku, Seoul, 06351, South Korea
- Neuroscience Center, Samsung Medical Center, Seoul, South Korea
| | - Chul Hyoung Lyoo
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea
| | - Seongbeom Park
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Kangnam-ku, Seoul, 06351, South Korea
| | - Seung Jun Oh
- Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, South Korea
| | - Hanna Cho
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea
| | - Minyoung Oh
- Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, South Korea
| | - Young Hoon Ryu
- Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea
| | - Jae Yong Choi
- Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea
| | - Gil D Rabinovici
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA, USA
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Hee Jin Kim
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Kangnam-ku, Seoul, 06351, South Korea
- Neuroscience Center, Samsung Medical Center, Seoul, South Korea
| | - Seung Hwan Moon
- Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Hyemin Jang
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Kangnam-ku, Seoul, 06351, South Korea
- Neuroscience Center, Samsung Medical Center, Seoul, South Korea
| | - Jin San Lee
- Department of Neurology, Kyung Hee University Hospital, Seoul, South Korea
| | - William J Jagust
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
- Center of Functional Imaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Duk L Na
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Kangnam-ku, Seoul, 06351, South Korea
- Neuroscience Center, Samsung Medical Center, Seoul, South Korea
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, South Korea
| | - Jae Seung Kim
- Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, South Korea.
| | - Sang Won Seo
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Kangnam-ku, Seoul, 06351, South Korea.
- Neuroscience Center, Samsung Medical Center, Seoul, South Korea.
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, South Korea.
- Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, Seoul, South Korea.
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141
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Barrio JR. The Irony of PET Tau Probe Specificity. J Nucl Med 2017; 59:115-116. [DOI: 10.2967/jnumed.117.198960] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 08/23/2017] [Indexed: 11/16/2022] Open
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Schonhaut DR, McMillan CT, Spina S, Dickerson BC, Siderowf A, Devous MD, Tsai R, Winer J, Russell DS, Litvan I, Roberson ED, Seeley WW, Grinberg LT, Kramer JH, Miller BL, Pressman P, Nasrallah I, Baker SL, Gomperts SN, Johnson KA, Grossman M, Jagust WJ, Boxer AL, Rabinovici GD. 18 F-flortaucipir tau positron emission tomography distinguishes established progressive supranuclear palsy from controls and Parkinson disease: A multicenter study. Ann Neurol 2017; 82:622-634. [PMID: 28980714 DOI: 10.1002/ana.25060] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 09/10/2017] [Accepted: 09/24/2017] [Indexed: 12/14/2022]
Abstract
OBJECTIVE 18 F-flortaucipir (formerly 18 F-AV1451 or 18 F-T807) binds to neurofibrillary tangles in Alzheimer disease, but tissue studies assessing binding to tau aggregates in progressive supranuclear palsy (PSP) have yielded mixed results. We compared in vivo 18 F-flortaucipir uptake in patients meeting clinical research criteria for PSP (n = 33) to normal controls (n = 46) and patients meeting criteria for Parkinson disease (PD; n = 26). METHODS Participants underwent magnetic resonance imaging and positron emission tomography for amyloid-β (11 C-PiB or 18 F-florbetapir) and tau (18 F-flortaucipir). 18 F-flortaucipir standardized uptake value ratios were calculated (t = 80-100 minutes, cerebellum gray matter reference). Voxelwise and region-of-interest group comparisons were performed in template space, with receiver operating characteristic curve analyses to assess single-subject discrimination. Qualitative comparisons with postmortem tau are reported in 1 patient who died 9 months after 18 F-flortaucipir. RESULTS Clinical PSP patients showed bilaterally elevated 18 F-flortaucipir uptake in globus pallidus, putamen, subthalamic nucleus, midbrain, and dentate nucleus relative to controls and PD patients (voxelwise p < 0.05 family wise error corrected). Globus pallidus binding best distinguished PSP patients from controls and PD (area under the curve [AUC] = 0.872 vs controls, AUC = 0.893 vs PD). PSP clinical severity did not correlate with 18 F-flortaucipir in any region. A patient with clinical PSP and pathological diagnosis of corticobasal degeneration had severe tau pathology in PSP-related brain structures with good correspondence between in vivo 18 F-flortaucipir and postmortem tau neuropathology. INTERPRETATION 18 F-flortaucipir uptake was elevated in PSP versus controls and PD patients in a pattern consistent with the expected distribution of tau pathology. Ann Neurol 2017;82:622-634.
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Affiliation(s)
- Daniel R Schonhaut
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA.,Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Corey T McMillan
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Salvatore Spina
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA
| | - Bradford C Dickerson
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA
| | | | | | - Richard Tsai
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA
| | - Joseph Winer
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA
| | | | - Irene Litvan
- Department of Neurology, University of California, San Diego, San Diego, CA
| | - Erik D Roberson
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL
| | - William W Seeley
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA.,Department of Pathology, University of California, San Francisco, San Francisco, CA
| | - Lea T Grinberg
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA.,Department of Pathology, University of California, San Francisco, San Francisco, CA
| | - Joel H Kramer
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA
| | - Bruce L Miller
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA
| | - Peter Pressman
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA
| | - Ilya Nasrallah
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Suzanne L Baker
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA
| | - Stephen N Gomperts
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA
| | - Keith A Johnson
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA
| | - Murray Grossman
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - William J Jagust
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA
| | - Adam L Boxer
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA
| | - Gil D Rabinovici
- Memory and Aging Center, University of California, San Francisco, San Francisco, CA.,Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA
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143
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Marquié M, Verwer EE, Meltzer AC, Kim SJW, Agüero C, Gonzalez J, Makaretz SJ, Siao Tick Chong M, Ramanan P, Amaral AC, Normandin MD, Vanderburg CR, Gomperts SN, Johnson KA, Frosch MP, Gómez-Isla T. Lessons learned about [F-18]-AV-1451 off-target binding from an autopsy-confirmed Parkinson's case. Acta Neuropathol Commun 2017; 5:75. [PMID: 29047416 PMCID: PMC5648451 DOI: 10.1186/s40478-017-0482-0] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 10/11/2017] [Indexed: 02/07/2023] Open
Abstract
[F-18]-AV-1451 is a novel positron emission tomography (PET) tracer with high affinity to neurofibrillary tau pathology in Alzheimer’s disease (AD). PET studies have shown increased tracer retention in patients clinically diagnosed with dementia of AD type and mild cognitive impairment in regions that are known to contain tau lesions. In vivo uptake has also consistently been observed in midbrain, basal ganglia and choroid plexus in elderly individuals regardless of their clinical diagnosis, including clinically normal whose brains are not expected to harbor tau pathology in those areas. We and others have shown that [F-18]-AV-1451 exhibits off-target binding to neuromelanin, melanin and blood products on postmortem material; and this is important for the correct interpretation of PET images. In the present study, we further investigated [F-18]-AV-1451 off-target binding in the first autopsy-confirmed Parkinson’s disease (PD) subject who underwent antemortem PET imaging. The PET scan showed elevated [F-18]-AV-1451 retention predominantly in inferior temporal cortex, basal ganglia, midbrain and choroid plexus. Neuropathologic examination confirmed the PD diagnosis. Phosphor screen and high resolution autoradiography failed to show detectable [F-18]-AV-1451 binding in multiple brain regions examined with the exception of neuromelanin-containing neurons in the substantia nigra, leptomeningeal melanocytes adjacent to ventricles and midbrain, and microhemorrhages in the occipital cortex (all reflecting off-target binding), in addition to incidental age-related neurofibrillary tangles in the entorhinal cortex. Additional legacy postmortem brain samples containing basal ganglia, choroid plexus, and parenchymal hemorrhages from 20 subjects with various neuropathologic diagnoses were also included in the autoradiography experiments to better understand what [F-18]-AV-1451 in vivo positivity in those regions means. No detectable [F-18]-AV-1451 autoradiographic binding was present in the basal ganglia of the PD case or any of the other subjects. Off-target binding in postmortem choroid plexus samples was only observed in subjects harboring leptomeningeal melanocytes within the choroidal stroma. Off-target binding to parenchymal hemorrhages was noticed in postmortem material from subjects with cerebral amyloid angiopathy. The imaging-postmortem correlation analysis in this PD case reinforces the notion that [F-18]-AV-1451 has strong affinity for neurofibrillary tau pathology but also exhibits off-target binding to neuromelanin, melanin and blood components. The robust off-target in vivo retention in basal ganglia and choroid plexus, in the absence of tau deposits, meningeal melanocytes or any other identifiable binding substrate by autoradiography in the PD case reported here, also suggests that the PET signal in those regions may be influenced, at least in part, by biological or technical factors that occur in vivo and are not captured by autoradiography.
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144
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Baker SL, Maass A, Jagust WJ. Considerations and code for partial volume correcting [ 18F]-AV-1451 tau PET data. Data Brief 2017; 15:648-657. [PMID: 29124088 PMCID: PMC5671473 DOI: 10.1016/j.dib.2017.10.024] [Citation(s) in RCA: 185] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 10/11/2017] [Accepted: 10/12/2017] [Indexed: 12/18/2022] Open
Abstract
[18F]-AV-1451 is a leading tracer used with positron emission tomography (PET) to quantify tau pathology. However, [18F]-AV-1451 shows “off target” or non-specific binding, which we define as binding of the tracer in unexpected areas unlikely to harbor aggregated tau based on autopsy literature [1]. Along with caudate, putamen, pallidum and thalamus non-specific binding [2], [3], we have found binding in the superior portion of the cerebellar gray matter, leading us to use inferior cerebellar gray as the reference region. We also addressed binding in the posterior portion of the choroid plexus. PET signal unlikely to be associated with tau also occurs in skull, meninges and soft tissue (see e.g. [4]). We refer to [18F]-AV-1451 binding in the skull and meninges as extra-cortical hotspots (ECH) and find them near lateral and medial orbitofrontal, lateral occipital, inferior and middle temporal, superior and inferior parietal, and inferior cerebellar gray matter. Lastly, the choroid plexus also shows non-specific binding that bleeds into hippocampus. We are providing the code (http://www.runmycode.org/companion/view/2798) used to create different regions of interest (ROIs) that we then used to perform Partial Volume Correction (PVC) using the Rousset geometric transfer matrix method (GTM, [5]). This method was used in the companion article, “Comparison of multiple tau-PET measures as biomarkers in aging and Alzheimer's Disease” ([6], DOI 10.1016/j.neuroimage.2017.05.058).
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Affiliation(s)
- Suzanne L Baker
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Anne Maass
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States.,German Center for Neurodegenerative Diseases, Magdeburg, Germany
| | - William J Jagust
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, United States.,Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States
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145
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Staffaroni AM, Elahi FM, McDermott D, Marton K, Karageorgiou E, Sacco S, Paoletti M, Caverzasi E, Hess CP, Rosen HJ, Geschwind MD. Neuroimaging in Dementia. Semin Neurol 2017; 37:510-537. [PMID: 29207412 PMCID: PMC5823524 DOI: 10.1055/s-0037-1608808] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Although the diagnosis of dementia still is primarily based on clinical criteria, neuroimaging is playing an increasingly important role. This is in large part due to advances in techniques that can assist with discriminating between different syndromes. Magnetic resonance imaging remains at the core of differential diagnosis, with specific patterns of cortical and subcortical changes having diagnostic significance. Recent developments in molecular PET imaging techniques have opened the door for not only antemortem but early, even preclinical, diagnosis of underlying pathology. This is vital, as treatment trials are underway for pharmacological agents with specific molecular targets, and numerous failed trials suggest that earlier treatment is needed. This article provides an overview of classic neuroimaging findings as well as new and cutting-edge research techniques that assist with clinical diagnosis of a range of dementia syndromes, with an emphasis on studies using pathologically proven cases.
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Affiliation(s)
- Adam M. Staffaroni
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
| | - Fanny M. Elahi
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
| | - Dana McDermott
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
| | - Kacey Marton
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
| | - Elissaios Karageorgiou
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
- Neurological Institute of Athens, Athens, Greece
| | - Simone Sacco
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
- Institute of Radiology, Department of Clinical Surgical Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy
| | - Matteo Paoletti
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
- Institute of Radiology, Department of Clinical Surgical Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy
| | - Eduardo Caverzasi
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Christopher P. Hess
- Division of Neuroradiology, Department of Radiology, University of California, San Francisco (UCSF), California
| | - Howard J. Rosen
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
| | - Michael D. Geschwind
- Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California
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146
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[F-18]-AV-1451 binding correlates with postmortem neurofibrillary tangle Braak staging. Acta Neuropathol 2017; 134:619-628. [PMID: 28612291 DOI: 10.1007/s00401-017-1740-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/08/2017] [Accepted: 06/08/2017] [Indexed: 01/16/2023]
Abstract
[F-18]-AV-1451, a PET tracer specifically developed to detect brain neurofibrillary tau pathology, has the potential to facilitate accurate diagnosis of Alzheimer's disease (AD), staging of brain tau burden and monitoring disease progression. Recent PET studies show that patients with mild cognitive impairment and AD dementia exhibit significantly higher in vivo [F-18]-AV-1451 retention than cognitively normal controls. Importantly, PET patterns of [F-18]-AV-1451 correlate well with disease severity and seem to match the predicted topographic Braak staging of neurofibrillary tangles (NFTs) in AD, although this awaits confirmation. We studied the correlation of autoradiographic binding patterns of [F-18]-AV-1451 and the stereotypical spatiotemporal pattern of progression of NFTs using legacy postmortem brain samples representing different Braak NFT stages (I-VI). We performed [F-18]-AV-1451 phosphor-screen autoradiography and quantitative tau measurements (stereologically based NFT counts and biochemical analysis of tau pathology) in three brain regions (entorhinal cortex, superior temporal sulcus and visual cortex) in a total of 22 cases: low Braak (I-II, n = 6), intermediate Braak (III-IV, n = 7) and high Braak (V-VI, n = 9). Strong and selective [F-18]-AV-1451 binding was detected in all tangle-containing regions matching precisely the observed pattern of PHF-tau immunostaining across the different Braak stages. As expected, no signal was detected in the white matter or other non-tangle containing regions. Quantification of [F-18]-AV-1451 binding was very significantly correlated with the number of NFTs present in each brain region and with the total tau and phospho-tau content as reported by Western blot and ELISA. [F-18]-AV-1451 is a promising biomarker for in vivo quantification of brain tau burden in AD. Neuroimaging-pathologic studies conducted on postmortem material from individuals imaged while alive are now needed to confirm these observations.
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147
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Villemagne VL. Selective Tau Imaging: Der Stand der Dinge. J Nucl Med 2017; 59:175-176. [PMID: 28935837 DOI: 10.2967/jnumed.117.198325] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 09/13/2017] [Indexed: 11/16/2022] Open
Affiliation(s)
- Victor L Villemagne
- Department of Molecular Imaging and Therapy, Austin Health, Melbourne, Australia; Department of Medicine, Austin Health, University of Melbourne, Melbourne, Australia; and Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia
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148
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Bischof GN, Endepols H, van Eimeren T, Drzezga A. Tau-imaging in neurodegeneration. Methods 2017; 130:114-123. [PMID: 28790016 DOI: 10.1016/j.ymeth.2017.08.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 07/25/2017] [Accepted: 08/04/2017] [Indexed: 10/19/2022] Open
Abstract
Pathological cerebral aggregations of proteins are suggested to play a crucial role in the development of neurodegenerative disorders. For example, aggregation of the protein ß-amyloid in form of extracellular amyloid-plaques as well as intraneuronal depositions of the protein tau in form of neurofibrillary tangles represent hallmarks of Alzheimer's disease (AD). Recently, novel tracers for in vivo molecular imaging of tau-aggregates in the brain have been introduced, complementing existing tracers for imaging amyloid-plaques. Available data on these novel tracers indicate that the subject of Tau-PET may be of considerable complexity. On the one hand this refers to the various forms of appearance of tau-pathology in different types of neurodegenerative disorders. On the other hand, a number of hurdles regarding validation of these tracers still need to be overcome with regard to comparability and standardization of the different tracers, observed off-target/non-specific binding and quantitative interpretation of the signal. These issues will have to be clarified before systematic clinical application of this exciting new methodological approach may become possible. Potential applications refer to early detection of neurodegeneration, differential diagnosis between tauopathies and non-tauopathies and specific patient selection and follow-up in therapy trials.
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Affiliation(s)
| | - Heike Endepols
- Department of Nuclear Medicine, University of Cologne, Germany
| | - Thilo van Eimeren
- Department of Nuclear Medicine, University of Cologne, Germany; German Research Center for Neurodegenerative Diseases (DZNE), Germany
| | - Alexander Drzezga
- Department of Nuclear Medicine, University of Cologne, Germany; German Research Center for Neurodegenerative Diseases (DZNE), Germany.
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149
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Abstract
Measures of the severity of cognitive impairment or parkinsonism are the usual endpoints in clinical trials for Alzheimer’s disease (AD) and Parkinson’s disease (PD), but are critically hampered by their lack of disease sensitivity and specificity. Due to the high failure rate of clinical trials, the rate of regulatory approval for efficacious new drugs has stagnated in the past few decades, with the gap between basic science discovery and clinical application metaphorically termed the “Valley of Death”. While the causes for this are probably multiple and complex, the usage of biomarkers as surrogate endpoints, particularly when they are molecularly-specific for the disease, has achieved some success in cancer trials, and it is likely that neurodegenerative disease trials would benefit from the same approach. As dementia and parkinsonism are not disease-specific clinical syndromes, both AD and PD trials have been flawed by reliance on clinical diagnosis and clinical endpoints. Clinical improvement has been a requirement for regulatory approval, but molecularly-specific biomarkers should improve both diagnostic accuracy and tracking of disease progression, allowing quicker screening of drug candidates. However, even when a molecularly-specific biomarker is found, such as amyloid imaging for AD, it may not reflect the entire extant molecular disease repertoire and may not serve equally well in the different roles of preclinical detection, diagnostic confirmation and surrogate endpoint, necessitating the usage of two, three or more biomarkers, deployed in series or in parallel.
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150
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Mathis CA, Lopresti BJ, Ikonomovic MD, Klunk WE. Small-molecule PET Tracers for Imaging Proteinopathies. Semin Nucl Med 2017; 47:553-575. [PMID: 28826526 DOI: 10.1053/j.semnuclmed.2017.06.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In this chapter, we provide a review of the challenges and advances in developing successful PET imaging agents for 3 major types of aggregated amyloid proteins: amyloid-beta (Aβ), tau, and alpha-synuclein (α-syn). These 3 amyloids are involved in the pathogenesis of a variety of neurodegenerative diseases, referred to as proteinopathies or proteopathies, that include Alzheimer disease, Lewy body dementias, multiple system atrophy, and frontotemporal dementias, among others. In the Introduction section, we briefly discuss the history of amyloid in neurodegenerative diseases and describe why progress in developing effective imaging agents has been hampered by the failure of crystallography to provide definitive ligand-protein interactions for rational radioligand design efforts. Instead, the field has relied on largely serendipitous, trial-and-error methods to achieve useful and specific PET amyloid imaging tracers for Aβ, tau, and α-syn deposits. Because many of the proteopathies involve more than 1 amyloid protein, it is important to develop selective PET tracers for the different amyloids to help assess the relative contribution of each to total amyloid burden. We use Pittsburgh compound B to illustrate some of the critical steps in developing a potent and selective Aβ PET imaging agent. Other selective Aβ and tau PET imaging compounds have followed similar pathways in their developmental processes. Success for selective α-syn PET imaging agents has not been realized yet, but work is ongoing in multiple laboratories throughout the world. In the tau sections, we provide background regarding 3-repeat (3R) and 4-repeat (4R) tau proteins and how they can affect the binding of tau radioligands in different tauopathies. We review the ongoing efforts to assess the properties of tau ligands, which are useful in 3R, 4R, or combined 3R-4R tauopathies. Finally, we describe in the α-syn sections recent attempts to develop selective tracers to image α-synucleinopathies.
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Affiliation(s)
- Chester A Mathis
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA.
| | - Brian J Lopresti
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Milos D Ikonomovic
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - William E Klunk
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA
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