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Sigurdsson EM. Tau Immunotherapies for Alzheimer's Disease and Related Tauopathies: Status of Trials and Insights from Preclinical Studies. J Alzheimers Dis 2024:JAD231238. [PMID: 38427486 DOI: 10.3233/jad-231238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
The tau protein undergoes pathological changes in Alzheimer's disease and other tauopathies that eventually lead to functional impairments. Over the years, several therapeutic approaches have been examined to slow or halt the progression of tau pathology but have yet to lead to an approved disease-modifying treatment. Of the drugs in clinical trials that directly target tau, immunotherapies are the largest category and mostly consist of antibodies in different stages of development. There is a reasonable optimism that at least some of these compounds will have a clinically meaningful efficacy. This view is based on the significant although modest efficacy of some antibodies targeting amyloid-β in Alzheimer's disease and the fact that tau pathology correlates much better with the degree of dementia than amyloid-β lesions. In Alzheimer's disease, clearing pathological tau may therefore improve function later in the disease process than when removing amyloid-β. This review provides a brief update on the active and passive clinical tau immunization trials with insight from preclinical studies. Various epitopes are being targeted and some of the antibodies are said to target extracellular tau but because almost all of pathological tau is found intracellularly, the most efficacious antibodies should be able to enter the cell.
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Affiliation(s)
- Einar M Sigurdsson
- Departments of Neuroscience and Physiology, and Psychiatry, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA
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2
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Congdon EE, Ji C, Tetlow AM, Jiang Y, Sigurdsson EM. Tau-targeting therapies for Alzheimer disease: current status and future directions. Nat Rev Neurol 2023; 19:715-736. [PMID: 37875627 PMCID: PMC10965012 DOI: 10.1038/s41582-023-00883-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2023] [Indexed: 10/26/2023]
Abstract
Alzheimer disease (AD) is the most common cause of dementia in older individuals. AD is characterized pathologically by amyloid-β (Aβ) plaques and tau neurofibrillary tangles in the brain, with associated loss of synapses and neurons, which eventually results in dementia. Many of the early attempts to develop treatments for AD focused on Aβ, but a lack of efficacy of these treatments in terms of slowing disease progression led to a change of strategy towards targeting of tau pathology. Given that tau shows a stronger correlation with symptom severity than does Aβ, targeting of tau is more likely to be efficacious once cognitive decline begins. Anti-tau therapies initially focused on post-translational modifications, inhibition of tau aggregation and stabilization of microtubules. However, trials of many potential drugs were discontinued because of toxicity and/or lack of efficacy. Currently, the majority of tau-targeting agents in clinical trials are immunotherapies. In this Review, we provide an update on the results from the initial immunotherapy trials and an overview of new therapeutic candidates that are in clinical development, as well as considering future directions for tau-targeting therapies.
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Affiliation(s)
- Erin E Congdon
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA
| | - Changyi Ji
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA
| | - Amber M Tetlow
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA
| | - Yixiang Jiang
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA
| | - Einar M Sigurdsson
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA.
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA.
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY, USA.
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3
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Douglas JT. My experience of living with nonfluent/agrammatic variant primary progressive aphasia: Challenges, compensatory strategies and adaptations. INTERNATIONAL JOURNAL OF LANGUAGE & COMMUNICATION DISORDERS 2023; 58:542-554. [PMID: 36239167 DOI: 10.1111/1460-6984.12798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Primary progressive aphasia (PPA) is a rare neurodegenerative brain disorder characterized by declining language ability. There is currently no way to reverse or slow the course of the progressive brain degeneration, nor is there a cure for PPA. Throughout the course of the disease, any treatment must therefore be palliative in nature and should be designed to manage symptoms and improve the quality of life of the affected person. There is little information in the medical literature about strategies to make meaningful improvements to the quality of life of people with PPA written from the perspective of those living with this condition. AIMS I have a clinical diagnosis of the nonfluent/agrammatic variant of PPA (nfvPPA), supported by imaging. In this report I discuss my experience of the progressive loss of language and communication skills, and detail the challenges I have been facing. I also describe how my quality of life has been enhanced by the early initiation of treatment focusing on communication strategies targeted to my specific impairments and designed to support my individual interests and goals. METHODS & PROCEDURES I was fortunate to obtain an early diagnosis from a cognitive neurologist experienced with PPA. From the onset of my language difficulties, I have received excellent personalized care from a multidisciplinary medical team including speech-language pathologists, a cognitive neurologist and other doctors. MAIN CONTRIBUTIONS My life during the early stage of nfvPPA has been enriched by personalized care focused on supporting the particular activities, interests and goals that are most important and meaningful to me. As my disease has progressed, I have benefited from an evolving range of strategies and adaptations targeted to the specific deficits in the areas of speaking, writing and reading that I have been facing at any given time. In addition, I have adopted methods to enhance the benefit of these language-directed strategies. And I have been employing evidence-based approaches that improve general brain health and thereby indirectly support my language. CONCLUSIONS & IMPLICATIONS My experience represents a model for the personalized care of people in the early stage of nfvPPA. WHAT THIS PAPER ADDS What is already known on the subject There is minimal information in the medical literature describing the subjective experience of a person with PPA. There is little information in the medical literature about strategies to make meaningful improvements to the quality of life of people in the early stage of PPA. What this paper adds to existing knowledge I have a clinical diagnosis of nfvPPA, supported by imaging. In this paper I give a first-person account of my experience of the progressive loss of language and communication skills, and I detail the challenges I have been facing. I describe how my quality of life during the early stage of nfvPPA has been enhanced by an evolving range of strategies and adaptations tailored to my speech and language deficits as they have arisen. These compensatory strategies have focused on supporting the particular activities, interests and goals that are most important and meaningful to me. What are the potential or actual clinical implications of this work? The description of my subjective experience of the progressive loss of language and communication skills offers insight for speech-language pathologists, neurologists and other professionals involved in the clinical care of people in the early stage of nfvPPA. My experience represents a model for the personalized clinical care of people in the early stage of this disorder.
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Affiliation(s)
- Joanne T Douglas
- Volunteer, Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care, The University of Alabama at Birmingham, Birmingham, AL, USA
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4
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Congdon EE, Pan R, Jiang Y, Sandusky-Beltran LA, Dodge A, Lin Y, Liu M, Kuo MH, Kong XP, Sigurdsson EM. Single domain antibodies targeting pathological tau protein: Influence of four IgG subclasses on efficacy and toxicity. EBioMedicine 2022; 84:104249. [PMID: 36099813 PMCID: PMC9475275 DOI: 10.1016/j.ebiom.2022.104249] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 08/15/2022] [Accepted: 08/19/2022] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Eleven tau immunoglobulin G (IgG) antibodies have entered clinical trials to treat tauopathies, including Alzheimer's disease, but it is unclear which IgG subclass/subtype has the ideal efficacy and safety profile. Only two subtypes, with or without effector function, have been examined in the clinic and not for the same tau antibody. The few preclinical studies on this topic have only compared two subtypes of one antibody each and have yielded conflicting results. METHODS We selected two single domain antibodies (sdAbs) derived from a llama immunized with tau proteins and utilized them to generate an array of Fc-(sdAb)2 subclasses containing identical tau binding domains but differing Fc region. Unmodified sdAbs and their IgG subclasses were tested for efficacy in primary cultures and in vivo microdialysis using JNPL3 tauopathy mice. FINDINGS Unmodified sdAbs were non-toxic, blocked tau toxicity and promoted tau clearance. However, the efficacy/safety profile of their Fc-(sdAb)2 subclasses varied greatly within and between sdAbs. For one of them, all its subtypes were non-toxic, only those with effector function cleared tau, and were more effective in vivo than unmodified sdAb. For the other sdAb, all its subtypes were toxic in tauopathy cultures but not in wild-type cells, suggesting that bivalent binding of its tau epitope stabilizes a toxic conformation of tau, with major implications for tau pathogenesis. Likewise, its subclasses were less effective than the unmodified sdAb in clearing tau in vivo. INTERPRETATION These findings indicate that tau antibodies with effector function are safe and better at clearing pathological tau than effectorless antibodies, Furthermore, tau antibodies can provide a valuable insight into tau pathogenesis, and some may aggravate it. FUNDING Funding for these studies was provided by the National Institute of Health (R01 AG032611, R01 NS077239, RF1 NS120488, R21 AG 069475, R21 AG 058282, T32AG052909), and the NYU Alzheimer's Disease Center Pilot Grant Program (via P30 AG008051).
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Affiliation(s)
- Erin E Congdon
- Department of Neuroscience and Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine, 435 East 30th Street, New York, NY 10016, USA
| | - Ruimin Pan
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Yixiang Jiang
- Department of Neuroscience and Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine, 435 East 30th Street, New York, NY 10016, USA
| | - Leslie A Sandusky-Beltran
- Department of Neuroscience and Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine, 435 East 30th Street, New York, NY 10016, USA
| | - Andie Dodge
- Department of Neuroscience and Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine, 435 East 30th Street, New York, NY 10016, USA
| | - Yan Lin
- Department of Neuroscience and Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine, 435 East 30th Street, New York, NY 10016, USA
| | - Mengyu Liu
- Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Road, Room 401, East Lansing, MI, 48824, USA
| | - Min-Hao Kuo
- Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Road, Room 401, East Lansing, MI, 48824, USA
| | - Xiang-Peng Kong
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Einar M Sigurdsson
- Department of Neuroscience and Physiology, and the Neuroscience Institute, New York University Grossman School of Medicine, 435 East 30th Street, New York, NY 10016, USA; Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, USA.
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5
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Song C, Shi J, Zhang P, Zhang Y, Xu J, Zhao L, Zhang R, Wang H, Chen H. Immunotherapy for Alzheimer's disease: targeting β-amyloid and beyond. Transl Neurodegener 2022; 11:18. [PMID: 35300725 PMCID: PMC8932191 DOI: 10.1186/s40035-022-00292-3] [Citation(s) in RCA: 77] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 02/25/2022] [Indexed: 12/16/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common neurodegenerative disease in the elderly worldwide. However, the complexity of AD pathogenesis leads to discrepancies in the understanding of this disease, and may be the main reason for the failure of AD drug development. Fortunately, many ongoing preclinical and clinical studies will continually open up avenues to unravel disease mechanisms and guide strategies for AD diagnosis and drug development. For example, immunotherapeutic strategies targeting amyloid-β (Aβ) and tau proteins were once deemed almost certainly effective in clinical treatment due to the excellent preclinical results. However, the repeated failures of clinical trials on vaccines and humanized anti-Aβ and anti-tau monoclonal antibodies have resulted in doubts on this strategy. Recently, a new anti-Aβ monoclonal antibody (Aducanumab) has been approved by the US Food and Drug Administration, which brings us back to the realization that immunotherapy strategies targeting Aβ may be still promising. Meanwhile, immunotherapies based on other targets such as tau, microglia and gut-brain axis are also under development. Further research is still needed to clarify the forms and epitopes of targeted proteins to improve the accuracy and effectiveness of immunotherapeutic drugs. In this review, we focus on the immunotherapies based on Aβ, tau and microglia and their mechanisms of action in AD. In addition, we present up-to-date advances and future perspectives on immunotherapeutic strategies for AD.
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Affiliation(s)
- Chenghuan Song
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Jiyun Shi
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Pingao Zhang
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Yongfang Zhang
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Jianrong Xu
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Lanxue Zhao
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Rui Zhang
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Hao Wang
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China. .,Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China. .,Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China. .,Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China.
| | - Hongzhuan Chen
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China. .,Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China. .,Department of Clinical Pharmacy, Institute of Interdisciplinary Integrative Medicine Research, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China.
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6
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Staats KA, Borchelt DR, Tansey MG, Wymer J. Blood-based biomarkers of inflammation in amyotrophic lateral sclerosis. Mol Neurodegener 2022; 17:11. [PMID: 35073950 PMCID: PMC8785449 DOI: 10.1186/s13024-022-00515-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 12/30/2021] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a devastating neurodegenerative disease in which many processes are detected including (neuro)inflammation. Many drugs have been tested for ALS in clinical trials but most have failed to reach their primary endpoints. The development and inclusion of different types of biomarkers in diagnosis and clinical trials can assist in determining target engagement of a drug, in distinguishing between ALS and other diseases, and in predicting disease progression rate, drug responsiveness, or an adverse event. Ideally, among other characteristics, a biomarker in ALS correlates highly with a disease process in the central nervous system or with disease progression and is conveniently obtained in a peripheral tissue. Here, we describe the state of biomarkers of inflammation in ALS by focusing on peripherally detectable and cellular responses from blood cells, and provide new (combinatorial) directions for exploration that are now feasible due to technological advancements.
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Affiliation(s)
- Kim A. Staats
- Staats Life Sciences Consulting, LLC, Los Angeles, CA USA
| | - David R. Borchelt
- Department of Neuroscience, University of Florida College of Medicine, McKnight Brain Institute, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, Florida USA
| | - Malú Gámez Tansey
- Department of Neuroscience and Center for Translational Research in Neurodegenerative Disease at The University of Florida College of Medicine, Gainesville, Florida USA
| | - James Wymer
- Department of Neurology, University of Florida College of Medicine, Gainesville, Florida USA
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7
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Congdon EE, Jiang Y, Sigurdsson EM. Targeting tau only extracellularly is likely to be less efficacious than targeting it both intra- and extracellularly. Semin Cell Dev Biol 2021; 126:125-137. [PMID: 34896021 DOI: 10.1016/j.semcdb.2021.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/01/2021] [Accepted: 12/01/2021] [Indexed: 12/11/2022]
Abstract
Aggregation of the tau protein is thought to be responsible for the neurodegeneration and subsequent functional impairments in diseases that are collectively named tauopathies. Alzheimer's disease is the most common tauopathy, but the group consists of over 20 different diseases, many of which have tau pathology as their primary feature. The development of tau therapies has mainly focused on preventing the formation of and/or clearing these aggregates. Of these, immunotherapies that aim to either elicit endogenous tau antibodies or deliver exogenous ones are the most common approach in clinical trials. While their mechanism of action can involve several pathways, both extra- and intracellular, pharmaceutical companies have primarily focused on antibody-mediated clearance of extracellular tau. As we have pointed out over the years, this is rather surprising because it is well known that most of pathological tau protein is found intracellularly. It has been repeatedly shown by several groups over the past decades that antibodies can enter neurons and that their cellular uptake can be enhanced by various means, particularly by altering their charge. Here, we will briefly describe the potential extra- and intracellular mechanisms involved in antibody-mediated clearance of tau pathology, discuss these in the context of recent failures of some of the tau antibody trials, and finally provide a brief overview of how the intracellular efficacy of tau antibodies can potentially be further improved by certain modifications that aim to enhance tau clearance via specific intracellular degradation pathways.
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Affiliation(s)
- Erin E Congdon
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States.
| | - Yixiang Jiang
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States
| | - Einar M Sigurdsson
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States; Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, United States.
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8
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Douglas JT. My experience of living with nonfluent/agrammatic variant primary progressive aphasia: Adaptations and strategies to improve quality of life. DEMENTIA 2020; 20:936-951. [DOI: 10.1177/1471301220918344] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Primary progressive aphasia is a major clinical presentation of frontotemporal lobar degeneration and is a young-onset disorder characterized by deteriorating language skills. There is currently no cure for primary progressive aphasia, nor is it possible to slow the course of the underlying progressive brain degeneration. Hence the chief goal of treatment is palliative. Although the inability to employ language at one’s previous level represents a significant functional impairment for those affected, there is a dearth of information about how to make meaningful improvements to the quality of life of people in the early stages of primary progressive aphasia. I have a clinical diagnosis, supported by imaging, of the nonfluent/agrammatic variant of primary progressive aphasia and am under the care of a multidisciplinary medical team. This report is based on my ongoing experience and describes the development and implementation of an evolving set of targeted strategies and adaptations designed to enhance the quality of life of a person in the early stages of this disorder.
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Affiliation(s)
- Joanne T Douglas
- Volunteer, Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care The University of Alabama at Birmingham, USA
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9
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Abstract
Alzheimer disease (AD) is the most common form of dementia. Pathologically, AD is characterized by amyloid plaques and neurofibrillary tangles in the brain, with associated loss of synapses and neurons, resulting in cognitive deficits and eventually dementia. Amyloid-β (Aβ) peptide and tau protein are the primary components of the plaques and tangles, respectively. In the decades since Aβ and tau were identified, development of therapies for AD has primarily focused on Aβ, but tau has received more attention in recent years, in part because of the failure of various Aβ-targeting treatments in clinical trials. In this article, we review the current status of tau-targeting therapies for AD. Initially, potential anti-tau therapies were based mainly on inhibition of kinases or tau aggregation, or on stabilization of microtubules, but most of these approaches have been discontinued because of toxicity and/or lack of efficacy. Currently, the majority of tau-targeting therapies in clinical trials are immunotherapies, which have shown promise in numerous preclinical studies. Given that tau pathology correlates better with cognitive impairments than do Aβ lesions, targeting of tau is expected to be more effective than Aβ clearance once the clinical symptoms are evident. With future improvements in diagnostics, these two hallmarks of the disease might be targeted prophylactically.
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Affiliation(s)
- Erin E Congdon
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
| | - Einar M Sigurdsson
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA.
- Department of Psychiatry, New York University School of Medicine, New York, NY, USA.
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10
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Kuiperij HB, Versleijen AAM, Beenes M, Verwey NA, Benussi L, Paterlini A, Binetti G, Teunissen CE, Raaphorst J, Schelhaas HJ, Küsters B, Pijnenburg YAL, Ghidoni R, Verbeek MM. Tau Rather than TDP-43 Proteins are Potential Cerebrospinal Fluid Biomarkers for Frontotemporal Lobar Degeneration Subtypes: A Pilot Study. J Alzheimers Dis 2018; 55:585-595. [PMID: 27662293 DOI: 10.3233/jad-160386] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Frontotemporal dementia (FTD) is a heterogeneous disease both at the clinical, genetic, and pathobiological level. The underlying pathological spectrum (termed FTLD, frontotemporal lobar degeneration) is in most cases defined by accumulation of either tau (FTLD-tau) or TDP-43 proteins (FTLD-TDP). Biomarkers to differentiate these subtypes are not yet available, whereas these are essential requirements to study the natural course of disease and for homogeneous inclusion of patients in clinical studies. OBJECTIVE To study if a combination of total (t-) and phosphorylated (p-)tau, and t-TDP-43 and p-TDP-43 proteins in cerebrospinal fluid (CSF) is suitable to discriminate FTLD-tau and FTLD-TDP subtypes. METHODS We developed immunoassays for the quantification of t-TDP-43 and p-TDP-43 proteins and used commercially available assays for the quantification of t-tau and p-tau proteins. We quantified these proteins in ventricular CSF samples from neuropathologically defined FTLD-tau and FTLD-TDP cases to study the reflection of underlying brain pathology in CSF composition, and in lumbar CSF samples from FTLD-tau and FTLD-TDP patients to study the diagnostic potential of CSF biomarkers. RESULTS In ventricular CSF, t-TDP-43 and t-tau levels, when combined into one model, were significantly different between neuropathologically-defined FTLD-tau and FTLD-TDP cases. In a pilot study using lumbar CSF, the p-tau/t-tau ratio, but not t-TDP-43 levels, were significantly different between FTLD-TDP and FTLD-tau patients. CONCLUSION We conclude that with current available methods, CSF tau, rather than TDP-43 proteins, may have diagnostic value in the differentiation of FTLD patients with either tau or TDP-43 pathology.
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Affiliation(s)
- H Bea Kuiperij
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud Alzheimer Centre, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | | | - Marijke Beenes
- Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Nicolaas A Verwey
- Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands.,Present affiliation: Medisch Centrum Leeuwarden, Leeuwarden, The Netherlands
| | - Luisa Benussi
- Molecular Markers Lab, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Anna Paterlini
- Molecular Markers Lab, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Giuliano Binetti
- Molecular Markers Lab, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Charlotte E Teunissen
- Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands
| | - Joost Raaphorst
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud Alzheimer Centre, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Helenius J Schelhaas
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud Alzheimer Centre, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Benno Küsters
- Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Yolande A L Pijnenburg
- Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
| | - Roberta Ghidoni
- Molecular Markers Lab, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Marcel M Verbeek
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud Alzheimer Centre, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
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11
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De Conti L, Borroni B, Baralle M. New routes in frontotemporal dementia drug discovery. Expert Opin Drug Discov 2017; 12:659-671. [DOI: 10.1080/17460441.2017.1329294] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Laura De Conti
- Biotechnology Development Group, International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Barbara Borroni
- Centre for Neurodegenerative Disorders - Neurology Unit, University of Brescia, Brescia, Italy
| | - Marco Baralle
- Biotechnology Development Group, International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
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12
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Sancesario GM, Bernardini S. How many biomarkers to discriminate neurodegenerative dementia? Crit Rev Clin Lab Sci 2015; 52:314-26. [PMID: 26292074 DOI: 10.3109/10408363.2015.1051658] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A number of cerebrospinal fluid (CSF) biomarkers are currently used for the diagnosis of dementia. Opposite changes in the level of amyloid-β(1-42) versus total tau and phosphorylated-tau181 in the CSF reflect the specific pathology of Alzheimer's disease (AD) in the brain. This panel of biomarkers has proven to be effective to differentiate AD from controls and from the major types of neurodegenerative dementia, and to evaluate the progression from mild cognitive impairment to AD. In the absence of specific biomarkers reflecting the pathologies of the other most common forms of dementia, such as Lewy Body disease, Frontotemporal lobar degeneration, Creutzfeldt-Jakob disease, etc., the evaluation of biomarkers of AD pathology is used, attempting to exclude rather than to confirm AD. Other biomarkers included in the common clinical practice do not clearly relate to the underlying pathology: progranulin (PGRN) is a selective marker of frontotemporal dementia with mutations in the PGRN gene; the 14-3-3 protein is a highly sensitive and specific marker for Creutzfeldt-Jakob disease, but has to be used carefully in differentiating rapid progressive dementia; and α-synuclein is an emerging candidate biomarker of the different forms of synucleinopathy. This review summarizes several biomarkers of neurodegenerative dementia validated based on the neuropathological processes occurring in brain tissue. Notwithstanding the paucity of pathologically validated biomarkers and their high analytical variability, the combinations of these biomarkers may well represent a key and more precise analytical and diagnostic tool in the complex plethora of degenerative dementia.
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Affiliation(s)
- Giulia M Sancesario
- a Department of Clinical and Behavioural Neurology , Santa Lucia Foundation, IRCCS , Rome , Italy and
| | - Sergio Bernardini
- b Department of Experimental Medicine and Surgery , Tor Vergata University of Rome , Rome , Italy
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TDP-43 as a possible biomarker for frontotemporal lobar degeneration: a systematic review of existing antibodies. Acta Neuropathol Commun 2015; 3:15. [PMID: 25853864 PMCID: PMC4380254 DOI: 10.1186/s40478-015-0195-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 02/05/2015] [Indexed: 12/12/2022] Open
Abstract
Frontotemporal lobar degeneration (FTLD) is one of the leading causes of dementia after Alzheimer’s disease. A high-ranking candidate to become a diagnostic marker for a major pathological subtype of FTLD is the transactive response DNA binding protein of 43 kDa (TDP-43). The main objective is to elucidate which antibodies are specific for pathological TDP-43, with special interest in its modified isoforms. Indeed, TDP-43 has been shown to be hyperphosphorylated and truncated in disease. A secondary objective is to review existing immunoassays that quantify TDP-43 in biofluids. A systematic review of literature was performed by searching PubMed and Web of Science using predefined keywords. Of considered research papers the methods section was reviewed to select publications that enabled us to answer our learning objective. After quality assessment, antibody characteristics and related outcomes were extracted. We identified a series of well-characterized antibodies based on a scoring system that assessed the ability of each antibody to detect TDP-43 pathology. A selection of 29 unique antibodies was made comprising 10 high-ranking antibodies which were reported multiple times to detect TDP-43 pathology in both immunostaining and immunoblotting experiments and 19 additional antibodies which detected TDP-43 pathology but were only scored once. This systematic review provides an overview of antibodies that are reported to detect pathological TDP-43. These antibodies can be used in future studies of TDP-43 proteinopathies. Additionally, selected antibodies hold the potential to be used in the development of novel immunoassays for the quantification of TDP-43 in biofluids, as a possible biomarker for FTLD-TDP.
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14
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D'Alton S, Lewis J. Therapeutic and diagnostic challenges for frontotemporal dementia. Front Aging Neurosci 2014; 6:204. [PMID: 25191265 PMCID: PMC4137452 DOI: 10.3389/fnagi.2014.00204] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 07/25/2014] [Indexed: 12/12/2022] Open
Abstract
In the search for therapeutic modifiers, frontotemporal dementia (FTD) has traditionally been overshadowed by other conditions such as Alzheimer's disease (AD). A clinically and pathologically diverse condition, FTD has been galvanized by a number of recent discoveries such as novel genetic variants in familial and sporadic forms of disease and the identification of TAR DNA binding protein of 43 kDa (TDP-43) as the defining constituent of inclusions in more than half of cases. In combination with an ever-expanding knowledge of the function and dysfunction of tau-a protein which is pathologically aggregated in the majority of the remaining cases-there exists a greater understanding of FTD than ever before. These advances may indicate potential approaches for the development of hypothetical therapeutics, but FTD remains highly complex and the roles of tau and TDP-43 in neurodegeneration are still wholly unclear. Here the challenges facing potential therapeutic strategies are discussed, which include sufficiently accurate disease diagnosis and sophisticated technology to deliver effective therapies.
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Affiliation(s)
- Simon D'Alton
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida Gainesville, FL, USA
| | - Jada Lewis
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida Gainesville, FL, USA
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15
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Miller JB, Banks SJ, Léger GC, Cummings JL. Randomized controlled trials in frontotemporal dementia: cognitive and behavioral outcomes. Transl Neurodegener 2014; 3:12. [PMID: 24921043 PMCID: PMC4052335 DOI: 10.1186/2047-9158-3-12] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 06/01/2014] [Indexed: 12/13/2022] Open
Abstract
Progress has been made in understanding the genetics and molecular biology of frontotemporal dementia (FTD). Targets for intervention have been identified, therapies are being developed, and clinical trials are advancing. A major challenge for FTD research is that multiple underlying pathologies can be associated with heterogeneous phenotypes. The neuropsychological profiles associated with FTD spectrum disorders often include executive dysfunction, language impairments and behavioral disturbance. Behavioral variant FTD is characterized by an initial presentation of changes in personality, behavior and/or emotion, which are often difficult to objectively capture using traditional neuropsychological measures. The two principal language variants of FTD are Progressive Nonfluent Aphasia (PNFA) with predominant agrammatic/non-fluent impairments and Semantic Dementia (SD) with semantic impairments and visual agnosia. Selection of appropriate endpoints for clinical trials is critical to ensure that the measures are adequately sensitive to detect change, yet specific enough to isolate signal from noise, and acceptable to regulatory agencies. Given the anticipated potential for small effect sizes, measures must be able to identify small incremental changes over time. It is also imperative that the measures provide adequate coverage of the constructs or behaviors of interest. Selected outcome measures should be suitable for repeat administration, yet relatively robust to practice effects to ensure that observed changes reflect true signal variance and not residual effects due to repeated measurement or poor reliability. To facilitate widespread adoption as an endpoint, measures should be readily accessible. We provide several examples of potential global, composite, and individual cognitive measures, as well as behavioral measures promising for FTD trials. Development and application of appropriate trial outcomes is critically important to success in advancing new treatments for FTD patients.
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Affiliation(s)
- Justin B Miller
- Cleveland Clinic, Lou Ruvo Center for Brain Health, 888 W. Bonneville Ave, Las Vegas, Nevada 89106, USA
| | - Sarah J Banks
- Cleveland Clinic, Lou Ruvo Center for Brain Health, 888 W. Bonneville Ave, Las Vegas, Nevada 89106, USA
| | - Gabriel C Léger
- Cleveland Clinic, Lou Ruvo Center for Brain Health, 888 W. Bonneville Ave, Las Vegas, Nevada 89106, USA
| | - Jeffrey L Cummings
- Cleveland Clinic, Lou Ruvo Center for Brain Health, 888 W. Bonneville Ave, Las Vegas, Nevada 89106, USA
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16
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Suárez-Calvet M, Dols-Icardo O, Lladó A, Sánchez-Valle R, Hernández I, Amer G, Antón-Aguirre S, Alcolea D, Fortea J, Ferrer I, van der Zee J, Dillen L, Van Broeckhoven C, Molinuevo JL, Blesa R, Clarimón J, Lleó A. Plasma phosphorylated TDP-43 levels are elevated in patients with frontotemporal dementia carrying a C9orf72 repeat expansion or a GRN mutation. J Neurol Neurosurg Psychiatry 2014; 85:684-91. [PMID: 24309270 DOI: 10.1136/jnnp-2013-305972] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVES About a half of patients with frontotemporal dementia (FTD) has deposition of phosphorylated TDP-43 protein (pTDP-43) in the brain. We studied pTDP-43 and total TDP-43 levels in plasma and cerebrospinal fluid (CSF) in healthy controls and patients with FTD, including those carrying a repeat expansion in the C9orf72 gene or a mutation in GRN. METHODS We included 88 plasma samples of 10 C9orf72 expansion carriers, 5 GRN mutation carriers, 51 patients with FTD without a known mutation and 22 healthy controls. We also obtained CSF samples from 25 patients with FTD (2 with C9orf72 expansion and 3 with a GRN mutation) and 22 healthy controls. We measured pTDP-43 and total TDP-43 levels using sandwich ELISA. RESULTS Patients carrying the C9orf72 repeat expansion or a GRN mutation had significantly higher plasma and CSF levels of pTDP-43 than the remaining patients with FTD (p<0.05). In addition, plasma pTDP-43 levels were higher in patients with FTD carrying a C9orf72 expansion or GRN mutations than in healthy controls (p<0.05). CONCLUSIONS Our study shows that plasma pTDP-43 levels may be increased in some genetic forms of FTD known to be associated with TDP-43 proteinopathies.
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Affiliation(s)
- Marc Suárez-Calvet
- Neurology Department, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, , Barcelona, Spain
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Douglas JT. Adaptation to Early-Stage Nonfluent/Agrammatic Variant Primary Progressive Aphasia: A First-Person Account. Am J Alzheimers Dis Other Demen 2014; 29:289-92. [PMID: 24567528 PMCID: PMC10852638 DOI: 10.1177/1533317514523669] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2024]
Abstract
Primary progressive aphasia (PPA) is a young-onset neurodegenerative disorder characterized by declining language ability. The nonfluent/agrammatic variant of PPA (PPA-G) has the core features of agrammatism in language production and effortful, halting speech. As with other frontotemporal spectrum disorders, there is currently no cure for PPA, nor is it possible to slow the course of progression. The primary goal of treatment is therefore palliative in nature. However, there is a paucity of published information about strategies to make meaningful improvements to the quality of life of people with PPA, particularly in the early stages of the disease where any benefit could most be appreciated by the affected person. This report describes a range of strategies and adaptations designed to improve the quality of life of a person with early-stage PPA-G, based on my experience under the care of a multidisciplinary medical team.
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Affiliation(s)
- Joanne T Douglas
- Volunteer, Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care, The University of Alabama at Birmingham, Birmingham, AL, USA
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18
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Kwong LK, Irwin DJ, Walker AK, Xu Y, Riddle DM, Trojanowski JQ, Lee VMY. Novel monoclonal antibodies to normal and pathologically altered human TDP-43 proteins. Acta Neuropathol Commun 2014; 2:33. [PMID: 24690345 PMCID: PMC4023626 DOI: 10.1186/2051-5960-2-33] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 03/10/2014] [Indexed: 12/12/2022] Open
Abstract
The RNA/DNA-binding protein, TDP-43, is the key component of ubiquitinated inclusions characteristic of amyotrophic lateral sclerosis (ALS) and the majority of frontotemporal lobar degeneration (FTLD-TDP) referred to collectively as TDP-43 proteinopathies. To further elucidate mechanisms of pathological TDP-43 processing and identify TDP-43 epitopes that could be useful as potential biomarkers of TDP-43 proteinopathies, we developed a panel of novel monoclonal antibodies (MAbs) directed at regions extending across the length of TDP-43. Here, we confirm previous observations that there is no or minimal accumulation of TDP-43 N-terminal domains in neocortical inclusions in human TDP-43 proteinopathy tissues and we identify a subset of these MAbs that are specific for human versus mouse TDP-43. Notably, one of these MAbs recognized an epitope that preferentially detected pathological TDP-43 inclusions with negligible reactivity for normal nuclear TDP-43 resembling anti-phospho-TDP-43 specific antibodies that only bind pathological TDP-43. Hence, we infer that this new MAb recognizes a phosphorylation independent but disease-specific pathologic conformation in abnormal TDP-43. These data suggest that the novel MAbs reported here will be useful for patient-oriented research as well as for studies of animal and cell-based models of TDP-43 proteinopathies including ALS and FTLD-TDP.
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19
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Rohan Z, Matej R. Current Concepts in the Classification and Diagnosis of Frontotemporal Lobar Degenerations: A Practical Approach. Arch Pathol Lab Med 2014; 138:132-8. [DOI: 10.5858/arpa.2012-0510-rs] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Frontotemporal lobar degenerations are clinically, genetically, and molecularly heterogeneous diseases characterized by mainly frontal and temporal atrophy and affecting behavioral, language, cognitive, and motor functions. The term frontotemporal dementia incorporates 3 distinct clinical syndromes seen in frontotemporal degenerations: behavioral variant of frontotemporal dementia, progressive nonfluent aphasia, and semantic dementia. Progressive supranuclear palsy syndrome, corticobasal syndrome, and motor neuron disease syndrome are also associated with frontotemporal lobar degenerations. The neuropathologic hallmark of frontotemporal lobar degenerations is accumulation of abnormal proteins in the cytoplasm and nuclei of neurons and glial cells. Proteins involved in pathologic processes that represent the basis for frontotemporal lobar degeneration classification are tau protein, transactive response DNA-binding protein of 43 kDa, and “fused in sarcoma” protein. The aim of this review is to provide a summary of practical approaches for neuropathologic diagnostics of the rapidly evolving classifications of frontotemporal lobar degenerations.
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Affiliation(s)
- Zdenek Rohan
- From the Department of Pathology and Molecular Medicine, Thomayer Hospital, and the Department of Pathology, Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Radoslav Matej
- From the Department of Pathology and Molecular Medicine, Thomayer Hospital, and the Department of Pathology, Third Faculty of Medicine, Charles University, Prague, Czech Republic
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20
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Borroni B, Benussi A, Cosseddu M, Archetti S, Padovani A. Cerebrospinal fluid tau levels predict prognosis in non-inherited frontotemporal dementia. NEURODEGENER DIS 2013; 13:224-9. [PMID: 24029600 DOI: 10.1159/000353280] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 05/23/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The course of frontotemporal dementia (FTD) is heterogeneous and no predictors of survival are currently available. Cerebrospinal fluid (CSF) tau dosage has been demonstrated to be useful in predicting outcome over time in a number of neurological disorders. OBJECTIVE To assess CSF tau levels in FTD and to evaluate their prognostic value. METHODS Seventy-seven FTD patients with no mutations in known causative genes were consecutively enrolled, and CSF tau and phospho-tau levels analysed. Each patient was reassessed over time, and survival (i.e. death/bedridden and otherwise) was evaluated. The survival analysis was carried out by Cox proportional hazards regression models. RESULTS Patients with high CSF tau levels (≥400 pg/ml) had shorter survival than those with low CSF tau levels [hazard ratio (HR) = 3.406; 95% CI: 1.151-10.077; Wald χ(2) = 4.902; d.f. = 1; p = 0.027]. The association between tau levels and survival probability was confirmed after adjusting for age, gender, clinical phenotype and FTD clinical dementia rating at enrolment (HR = 3.769; 95% CI: 1.143-12.433; Wald χ(2) = 4.748; d.f. = 1; p = 0.029). Neither demographic or clinical characteristics nor CSF phospho-tau levels or apolipoprotein E genotype were significantly associated with prognosis. CONCLUSIONS This study argues that CSF tau levels may be considered in FTD to predict patients' outcome. Establishing in vivo prognostic biomarkers is mandatory to define homogeneous groups for inclusion in future clinical trials and to monitor the effectiveness of future therapeutic approaches.
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Affiliation(s)
- Barbara Borroni
- Centre for Neurodegenerative Disorders, University of Brescia, Brescia, Italy
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21
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Toledo JB, Van Deerlin VM, Lee EB, Suh E, Baek Y, Robinson JL, Xie SX, McBride J, Wood EM, Schuck T, Irwin DJ, Gross RG, Hurtig H, McCluskey L, Elman L, Karlawish J, Schellenberg G, Chen-Plotkin A, Wolk D, Grossman M, Arnold SE, Shaw LM, Lee VMY, Trojanowski JQ. A platform for discovery: The University of Pennsylvania Integrated Neurodegenerative Disease Biobank. Alzheimers Dement 2013; 10:477-484.e1. [PMID: 23978324 DOI: 10.1016/j.jalz.2013.06.003] [Citation(s) in RCA: 163] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 05/10/2013] [Accepted: 06/03/2013] [Indexed: 12/12/2022]
Abstract
Neurodegenerative diseases (NDs) are defined by the accumulation of abnormal protein deposits in the central nervous system (CNS), and only neuropathological examination enables a definitive diagnosis. Brain banks and their associated scientific programs have shaped the actual knowledge of NDs, identifying and characterizing the CNS deposits that define new diseases, formulating staging schemes, and establishing correlations between neuropathological changes and clinical features. However, brain banks have evolved to accommodate the banking of biofluids as well as DNA and RNA samples. Moreover, the value of biobanks is greatly enhanced if they link all the multidimensional clinical and laboratory information of each case, which is accomplished, optimally, using systematic and standardized operating procedures, and in the framework of multidisciplinary teams with the support of a flexible and user-friendly database system that facilitates the sharing of information of all the teams in the network. We describe a biobanking system that is a platform for discovery research at the Center for Neurodegenerative Disease Research at the University of Pennsylvania.
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Affiliation(s)
- Jon B Toledo
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - Vivianna M Van Deerlin
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - Edward B Lee
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - EunRan Suh
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - Young Baek
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - John L Robinson
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - Sharon X Xie
- Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jennifer McBride
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - Elisabeth M Wood
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - Theresa Schuck
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - David J Irwin
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - Rachel G Gross
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Howard Hurtig
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Leo McCluskey
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Lauren Elman
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jason Karlawish
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Gerard Schellenberg
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - Alice Chen-Plotkin
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - David Wolk
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Murray Grossman
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Steven E Arnold
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Leslie M Shaw
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - Virginia M-Y Lee
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA
| | - John Q Trojanowski
- Department of Pathology & Laboratory Medicine, Institute on Aging, Center for Neurodegenerative Disease Research, Philadelphia, Pennsylvania, USA.
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22
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Lattante S, Rouleau GA, Kabashi E. TARDBPandFUSMutations Associated with Amyotrophic Lateral Sclerosis: Summary and Update. Hum Mutat 2013; 34:812-26. [DOI: 10.1002/humu.22319] [Citation(s) in RCA: 183] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 02/28/2013] [Indexed: 12/11/2022]
Affiliation(s)
- Serena Lattante
- Institut du Cerveau et de la Moelle épinière; Centre de Recherche, CHU Pitié-Salpétrière, Inserm, UMR_S975, CRICM, F-75013; UPMC Univ Paris 06, UMR_S975, F-75013; CNRS UMR 7225; F-75013; Paris; France
| | - Guy A. Rouleau
- Montreal Neurological Institute; Department of Neurology and Neurosurgery, McGill University; Montreal; Canada
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Cruchaga C, Kauwe JSK, Harari O, Jin SC, Cai Y, Karch CM, Benitez BA, Jeng AT, Skorupa T, Carrell D, Bertelsen S, Bailey M, McKean D, Shulman JM, De Jager PL, Chibnik L, Bennett DA, Arnold SE, Harold D, Sims R, Gerrish A, Williams J, Van Deerlin VM, Lee VMY, Shaw LM, Trojanowski JQ, Haines JL, Mayeux R, Pericak-Vance MA, Farrer LA, Schellenberg GD, Peskind ER, Galasko D, Fagan AM, Holtzman DM, Morris JC, Goate AM. GWAS of cerebrospinal fluid tau levels identifies risk variants for Alzheimer's disease. Neuron 2013; 78:256-68. [PMID: 23562540 PMCID: PMC3664945 DOI: 10.1016/j.neuron.2013.02.026] [Citation(s) in RCA: 331] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2013] [Indexed: 01/18/2023]
Abstract
Cerebrospinal fluid (CSF) tau, tau phosphorylated at threonine 181 (ptau), and Aβ₄₂ are established biomarkers for Alzheimer's disease (AD) and have been used as quantitative traits for genetic analyses. We performed the largest genome-wide association study for cerebrospinal fluid (CSF) tau/ptau levels published to date (n = 1,269), identifying three genome-wide significant loci for CSF tau and ptau: rs9877502 (p = 4.89 × 10⁻⁹ for tau) located at 3q28 between GEMC1 and OSTN, rs514716 (p = 1.07 × 10⁻⁸ and p = 3.22 × 10⁻⁹ for tau and ptau, respectively), located at 9p24.2 within GLIS3 and rs6922617 (p = 3.58 × 10⁻⁸ for CSF ptau) at 6p21.1 within the TREM gene cluster, a region recently reported to harbor rare variants that increase AD risk. In independent data sets, rs9877502 showed a strong association with risk for AD, tangle pathology, and global cognitive decline (p = 2.67 × 10⁻⁴, 0.039, 4.86 × 10⁻⁵, respectively) illustrating how this endophenotype-based approach can be used to identify new AD risk loci.
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Affiliation(s)
- Carlos Cruchaga
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA
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Irwin DJ, Trojanowski JQ, Grossman M. Cerebrospinal fluid biomarkers for differentiation of frontotemporal lobar degeneration from Alzheimer's disease. Front Aging Neurosci 2013; 5:6. [PMID: 23440936 PMCID: PMC3578350 DOI: 10.3389/fnagi.2013.00006] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2013] [Accepted: 02/05/2013] [Indexed: 12/12/2022] Open
Abstract
Accurate ante mortem diagnosis in frontotemporal lobar degeneration (FTLD) is crucial to the development and implementation of etiology-based therapies. Several neurodegenerative disease-associated proteins, including the major protein constituents of inclusions in Alzheimer's disease (AD) associated with amyloid-beta (Aβ(1-42)) plaque and tau neurofibrillary tangle pathology, can be measured in cerebrospinal fluid (CSF) for diagnostic applications. Comparative studies using autopsy-confirmed samples suggest that CSF total-tau (t-tau) and Aβ(1-42) levels can accurately distinguish FTLD from AD, with a high t-tau to Aβ(1-42) ratio diagnostic of AD; however, there is also an urgent need for FTLD-specific biomarkers. These analytes will require validation in large autopsy-confirmed cohorts and face challenges of standardization of within- and between-laboratory sources of error. In addition, CSF biomarkers with prognostic utility and longitudinal study of CSF biomarker levels over the course of disease are also needed. Current goals in the field include identification of analytes that are easily and reliably measured and can be used alone or in a multi-modal approach to provide an accurate prediction of underlying neuropathology for use in clinical trials of disease modifying treatments in FTLD. To achieve these goals it will be of the utmost importance to view neurodegenerative disease, including FTLD, as a clinicopathological entity, rather than exclusively a clinical syndrome.
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Affiliation(s)
- David J Irwin
- Department of Pathology and Laboratory Medicine, Center for Neurodegenerative Disease Research, Alzheimer's Disease Core Center, Institute on Aging, University of Pennsylvania Philadelphia, PA, USA ; Department of Neurology, Center for Frontotemporal Dementia, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
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25
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Irwin DJ, McMillan CT, Toledo JB, Arnold SE, Shaw LM, Wang LS, Van Deerlin V, Lee VMY, Trojanowski JQ, Grossman M. Comparison of cerebrospinal fluid levels of tau and Aβ 1-42 in Alzheimer disease and frontotemporal degeneration using 2 analytical platforms. ACTA ACUST UNITED AC 2012; 69:1018-25. [PMID: 22490326 DOI: 10.1001/archneurol.2012.26] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE To use values of cerebrospinal fluid tau and β-amyloid obtained from 2 different analytical immunoassays to differentiate Alzheimer disease (AD) from frontotemporal lobar degeneration (FTLD). DESIGN Cerebrospinal fluid values of total tau (T-tau) and β-amyloid 1-42 (Aβ 1-42) obtained using the Innotest enzyme-linked immunosorbent assay were transformed using a linear regression model to equivalent values obtained using the INNO-BIA AlzBio3 (xMAP; Luminex) assay. Cutoff values obtained from the xMAP assay were developed in a series of autopsy-confirmed cases and cross validated in another series of autopsy-confirmed samples using transformed enzyme-linked immunosorbent assay values to assess sensitivity and specificity for differentiating AD from FTLD. SETTING Tertiary memory disorder clinics and neuropathologic and biomarker core centers. PARTICIPANTS Seventy-five samples from patients with cerebrospinal fluid data obtained from both assays were used for transformation of enzyme-linked immunosorbent assay values. Forty autopsy-confirmed cases (30 with AD and 10 with FTLD) were used to establish diagnostic cutoff values and then cross validated in a second sample set of 21 autopsy-confirmed cases (11 with AD and 10 with FTLD) with transformed enzyme-linked immunosorbent assay values. MAIN OUTCOME MEASURE Diagnostic accuracy using transformed biomarker values. RESULTS Data obtained from both assays were highly correlated. The T-tau to Aβ 1-42 ratio had the highest correlation between measures (r = 0.928, P < .001) and high reliability of transformation (intraclass correlation coefficient= 0.89). A cutoff of 0.34 for the T-tau to Aβ 1-42 ratio had 90% and 100% sensitivity and 96.7% and 91% specificity to differentiate FTLD cases in the validation and cross-validation samples, respectively. CONCLUSIONS Values from 2 analytical platforms can be transformed into equivalent units, which can distinguish AD from FTLD more accurately than the clinical diagnosis.
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Affiliation(s)
- David J Irwin
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, Institute on Aging, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
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Karakaya T, Fußer F, Prvulovic D, Hampel H. Treatment options for tauopathies. Curr Treat Options Neurol 2012; 14:126-36. [PMID: 22307450 DOI: 10.1007/s11940-012-0168-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OPINION STATEMENT To date, there are no approved and established pharmacologic treatment options for tauopathies, a very heterogenous group of neuropsychiatric diseases often leading to dementia and clinically diagnosed as atypical Parkinson syndromes. Among these so-called Parkinson plus syndromes are progressive supranuclear palsy (PSP), also referred to as Steele-Richardson-Olszewski syndrome; frontotemporal dementia (FTD); and corticobasal degeneration (CBD). Available treatment strategies are based mainly on small clinical trials, miscellaneous case reports, or small case-controlled studies. The results of these studies and conclusions about the efficacy of the medication used are often contradictory. Approved therapeutic agents for Alzheimer´s dementia, such as acetylcholinesterase inhibitors and memantine, have been used off-label to treat cognitive and behavioral symptoms in tauopathies, but the outcome has not been consistent. Therapeutic agents for the symptomatic treatment of Parkinson's disease (levodopa or dopamine agonists) are used for motor symptoms in tauopathies. For behavioral or psychopathological symptoms, treatment with antidepressants-especially selective serotonin reuptake inhibitors-could be helpful. Antipsychotics are often not well tolerated because of their adverse effects, which are pronounced in tauopathies; these drugs should be given very carefully because of an increased risk of cerebrovascular events. In addition to pharmacologic options, physical, occupational, or speech therapy can be applied to improve functional abilities. Each pharmacologic or nonpharmacologic intervention should be fitted to the specific symptoms of the individual patient, and decisions about the type and duration of treatment should be based on its efficacy for the individual and the patient's tolerance. Currently, no effective treatment is available that targets the cause of these diseases. Current research focuses on targeting tau protein pathology, including pathologic aggregation or phosphorylation; these approaches seem to be very promising.
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Affiliation(s)
- Tarik Karakaya
- Department of Psychiatry, J.W. Goethe-University, Heinrich-Hoffmann-Str. 10, 60528, Frankfurt, Germany,
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Coppe S, Orban de Xivry JJ, Yüksel D, Ivanoiu A, Lefèvre P. Dramatic impairment of prediction due to frontal lobe degeneration. J Neurophysiol 2012; 108:2957-66. [PMID: 22956792 DOI: 10.1152/jn.00582.2012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Prediction is essential for motor function in everyday life. For instance, predictive mechanisms improve the perception of a moving target by increasing eye speed anticipatively, thus reducing motion blur on the retina. Subregions of the frontal lobes play a key role in eye movements in general and in smooth pursuit in particular, but their precise function is not firmly established. Here, the role of frontal lobes in the timing of predictive action is demonstrated by studying predictive smooth pursuit during transient blanking of a moving target in mild frontotemporal lobar degeneration (FTLD) and Alzheimer's disease (AD) patients. While control subjects and AD patients predictively reaccelerated their eyes before the predicted time of target reappearance, FTLD patients did not. The difference was so dramatic (classification accuracy >90%) that it could even lead to the definition of a new biomarker. In contrast, anticipatory eye movements triggered by the disappearance of the fixation point were still present before target motion onset in FTLD patients and visually guided pursuit was normal in both patient groups compared with controls. Therefore, FTLD patients were only impaired when the predicted timing of an external event was required to elicit an action. These results argue in favor of a role of the frontal lobes in predictive movement timing.
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Affiliation(s)
- Sébastien Coppe
- ICTEAM, Université catholique de Louvain, Louvain-La-Neuve, Belgium
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28
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Huang C, Tong J, Bi F, Wu Q, Huang B, Zhou H, Xia XG. Entorhinal cortical neurons are the primary targets of FUS mislocalization and ubiquitin aggregation in FUS transgenic rats. Hum Mol Genet 2012; 21:4602-14. [PMID: 22833456 DOI: 10.1093/hmg/dds299] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Ubiquitin-positive inclusion containing Fused in Sarcoma (FUS) defines a new subtype of frontotemporal lobar degeneration (FTLD). FTLD is characterized by progressive alteration in cognitions and it preferentially affects the superficial layers of frontotemporal cortex. Mutation of FUS is linked to amyotrophic lateral sclerosis and to motor neuron disease with FTLD. To examine FUS pathology in FTLD, we developed the first mammalian animal model expressing human FUS with pathogenic mutation and developing progressive loss of memory. In FUS transgenic rats, ubiquitin aggregation and FUS mislocalization were developed primarily in the entorhinal cortex of temporal lobe, particularly in the superficial layers of affected cortex. Overexpression of mutant FUS led to Golgi fragmentation and mitochondrion aggregation. Intriguingly, aggregated ubiquitin was not colocalized with either fragmented Golgi or aggregated mitochondria, and neurons with ubiquitin aggregates were deprived of endogenous TDP-43. Agonists of peroxisome proliferator-activated receptor gamma (PPAR-γ) possess anti-glial inflammation effects and are also shown to preserve the dendrite and dendritic spines of cortical neurons in culture. Here we show that rosiglitazone, a PPAR-γ agonist, rescued the dendrites and dendritic spines of neurons from FUS toxicity and preserved rats' spatial memory. Our FUS transgenic rats would be useful to the mechanistic study of cortical dementia in FTLD. As rosiglitazone is clinically used to treat diabetes, our results would encourage immediate application of PPAR-γ agonists in treating patients with cortical dementia.
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Affiliation(s)
- Cao Huang
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
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CSF biomarkers cutoffs: the importance of coincident neuropathological diseases. Acta Neuropathol 2012; 124:23-35. [PMID: 22526019 DOI: 10.1007/s00401-012-0983-7] [Citation(s) in RCA: 124] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Revised: 04/07/2012] [Accepted: 04/08/2012] [Indexed: 12/13/2022]
Abstract
The effects of applying clinical versus neuropathological diagnosis and the inclusion of cases with coincident neuropathological diagnoses have not been assessed specifically when studying cerebrospinal fluid (CSF) biomarker classification cutoffs for patients with neurodegenerative diseases that cause dementia. Thus, 142 neuropathologically diagnosed neurodegenerative dementia patients [71 Alzheimer's disease (AD), 29 frontotemporal lobar degeneration (FTLD), 3 amyotrophic lateral sclerosis, 7 dementia with Lewy bodies, 32 of which cases also had coincident diagnoses] were studied. 96 % had enzyme-linked immunosorbant assay (ELISA) CSF data and 77 % had Luminex CSF data, with 43 and 46 controls for comparison, respectively. Aβ(42), total, and phosphorylated tau(181) were measured. Clinical and neuropathological diagnoses showed an 81.4 % overall agreement. Both assays showed high sensitivity and specificity to classify AD subjects against FTLD subjects and controls, and moderate sensitivity and specificity for classifying FTLD subjects against controls. However, among the cases with neuropathological diagnoses of AD plus another pathology (26.8 % of the sample), 69.4 % (ELISA) and 96.4 % (Luminex) were classified as AD according to their biomarker profiles. Use of clinical diagnosis instead of neuropathological diagnosis led to a 14-17 % underestimation of the biomarker accuracy. These results show that while CSF Aβ and tau assays are useful for diagnosis of AD and neurodegenerative diseases even at MCI stages, CSF diagnostic analyte panels that establish a positive diagnosis of Lewy body disease and FTLD are also needed, and must be established based on neuropathological rather than clinical diagnoses.
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Rademakers R, Neumann M, Mackenzie IR. Advances in understanding the molecular basis of frontotemporal dementia. Nat Rev Neurol 2012; 8:423-34. [PMID: 22732773 DOI: 10.1038/nrneurol.2012.117] [Citation(s) in RCA: 301] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Frontotemporal dementia (FTD) is a clinical syndrome with a heterogeneous molecular basis. Until recently, the underlying cause was known in only a minority of cases that were associated with abnormalities of the tau protein or gene. In 2006, however, mutations in the progranulin gene were discovered as another important cause of familial FTD. That same year, TAR DNA-binding protein 43 (TDP-43) was identified as the pathological protein in the most common subtypes of FTD and amyotrophic lateral sclerosis (ALS). Since then, substantial efforts have been made to understand the functions and regulation of progranulin and TDP-43, as well as their roles in neurodegeneration. More recently, other DNA/RNA binding proteins (FET family proteins) have been identified as the pathological proteins in most of the remaining cases of FTD. In 2011, abnormal expansion of a hexanucleotide repeat in the gene C9orf72 was found to be the most common genetic cause of both FTD and ALS. All common FTD-causing genes have seemingly now been discovered and the main pathological proteins identified. In this Review, we highlight recent advances in understanding the molecular aspects of FTD, which will provide the basis for improved patient care through the development of more-targeted diagnostic tests and therapies.
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Affiliation(s)
- Rosa Rademakers
- Department of Neuroscience, Mayo Clinic Florida, Jacksonville, FL 32224, USA
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Looi JCL, Walterfang M, Velakoulis D, Macfarlane MD, Svensson LA, Wahlund LO. Frontotemporal dementia as a frontostriatal disorder: neostriatal morphology as a biomarker and structural basis for an endophenotype. Aust N Z J Psychiatry 2012; 46:422-34. [PMID: 22535292 DOI: 10.1177/0004867411432076] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE This article reviews the evidence for a re-conceptualisation of a subtype of frontotemporal lobar degeneration (FTLD), frontotemporal dementia (FTD), as a frontostriatal disorder, working towards an endophenotype. METHOD We provide an overview of the role of frontostriatal circuits relevant to FTLD and FTD, as a subset of larger-scale distributed brain networks. We discuss the role of a strategic structure in these circuits, the neostriatum. Then we review the relationship of the clinical features of FTLD to frontostriatal circuits, correlating this with neuropsychological and neuropathological data. CONCLUSION The unique structure and linkages of the neostriatum make it an ideal structure for in vivo neuroimaging to understand the neuroanatomical basis of FTD. We develop a frontostriatal endophenotypic model for FTD as a platform for further investigation.
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Affiliation(s)
- Jeffrey C L Looi
- Research Centre for the Neurosciences of Ageing, Academic Unit of Psychological Medicine, Australian National University Medical School, Canberra Hospital, Canberra, Australia.
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Stougaard M, Juul S, Andersen FF, Knudsen BR. Strategies for highly sensitive biomarker detection by Rolling Circle Amplification of signals from nucleic acid composed sensors. Integr Biol (Camb) 2011; 3:982-92. [DOI: 10.1039/c1ib00049g] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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