51
|
Bell K, Gramlich OW, Von Thun Und Hohenstein-Blaul N, Beck S, Funke S, Wilding C, Pfeiffer N, Grus FH. Does autoimmunity play a part in the pathogenesis of glaucoma? Prog Retin Eye Res 2013; 36:199-216. [PMID: 23541978 DOI: 10.1016/j.preteyeres.2013.02.003] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 02/17/2013] [Accepted: 02/18/2013] [Indexed: 12/12/2022]
Abstract
Glaucoma is a chronic neurodegenerative disease and one of the leading causes of blindness. Several risk factors have been described, e.g. an elevated intraocular pressure (IOP), oxidative stress or mitochondrial dysfunction. Additionally, alterations in serum antibody profiles of glaucoma patients, upregulation (e.g. anti-HSP60, anti-MBP) and downregulation (e.g. anti-14-3-3), have been described, but it still remains elusive if the autoantibodies seen in glaucoma are an epiphenomenon or causative. However, it is known that elicited autoimmunity causes retinal ganglion cell loss resulting in glaucomatous-like damage and according to the autoaggressive nature of some autoantibodies we found antibody deposits in human glaucomatous retinae in a pro-inflammatory environment. Furthermore, glaucomatous serum has the potential to influence neuroretinal cell regulatory processes. Importantly, we demonstrate that some autoantibodies hold neuroprotective potential for neuroretinal cells. The protective nature of autoantibodies and the molecular mechanisms underlying the very sensitive equilibrium between autoaggression and protection remain subject of future examinations and offer promising target sites for new therapeutic approaches. Additionally, the changes in antibody profiles could be used as highly sensitive and specific marker for diagnostics purposes. Early diagnosis and intervention in risk patients would offer the chance of early treatment and to slow down the progression of glaucoma and delay the resulting blindness.
Collapse
Affiliation(s)
- Katharina Bell
- Experimental Ophthalmology, Department of Ophthalmology, University Medical Center of the Johannes Gutewnberg University, Langenbeckstr. 1, 55131 Mainz, Germany
| | | | | | | | | | | | | | | |
Collapse
|
52
|
Bhattacharya SK, Lee RK, Grus FH. Molecular biomarkers in glaucoma. Invest Ophthalmol Vis Sci 2013; 54:121-31. [PMID: 23297392 PMCID: PMC3544416 DOI: 10.1167/iovs.12-11067] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 10/29/2012] [Indexed: 12/20/2022] Open
Affiliation(s)
| | - Richard K. Lee
- From the
Bascom Palmer Eye Institute, University of Miami, Miami, Florida; and
| | - Franz H. Grus
- Experimental Ophthalmology, Department of Ophthalmology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | | |
Collapse
|
53
|
Yiannopoulou KG, Papageorgiou SG. Current and future treatments for Alzheimer's disease. Ther Adv Neurol Disord 2013; 6:19-33. [PMID: 23277790 PMCID: PMC3526946 DOI: 10.1177/1756285612461679] [Citation(s) in RCA: 381] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Alzheimer's dementia (AD) is increasingly being recognized as one of the most important medical and social problems in older people in industrialized and non-industrialized nations. To date, only symptomatic treatments exist for this disease, all trying to counterbalance the neurotransmitter disturbance. Three cholinesterase inhibitors (CIs) are currently available and have been approved for the treatment of mild to moderate AD. A further therapeutic option available for moderate to severe AD is memantine, an N-methyl-D-aspartate receptor noncompetitive antagonist. Treatments capable of stopping or at least effectively modifying the course of AD, referred to as 'disease-modifying' drugs, are still under extensive research. To block the progression of the disease they have to interfere with the pathogenic steps responsible for the clinical symptoms, including the deposition of extracellular amyloid β plaques and intracellular neurofibrillary tangle formation, inflammation, oxidative damage, iron deregulation and cholesterol metabolism. In this review we discuss current symptomatic treatments and new potential disease-modifying therapies for AD that are currently being studied in phase I-III trials.
Collapse
|
54
|
Welzel AT, Williams AD, McWilliams-Koeppen HP, Acero L, Weber A, Blinder V, Mably A, Bunk S, Hermann C, Farrell MA, Ehrlich HJ, Schwarz HP, Walsh DM, Solomon A, O’Nuallain B. Human anti-Aβ IgGs target conformational epitopes on synthetic dimer assemblies and the AD brain-derived peptide. PLoS One 2012; 7:e50317. [PMID: 23209707 PMCID: PMC3507685 DOI: 10.1371/journal.pone.0050317] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 10/18/2012] [Indexed: 01/08/2023] Open
Abstract
Soluble non-fibrillar assemblies of amyloid-beta (Aβ) and aggregated tau protein are the proximate synaptotoxic species associated with Alzheimer's disease (AD). Anti-Aβ immunotherapy is a promising and advanced therapeutic strategy, but the precise Aβ species to target is not yet known. Previously, we and others have shown that natural human IgGs (NAbs) target diverse Aβ conformers and have therapeutic potential. We now demonstrate that these antibodies bound with nM avidity to conformational epitopes on plate-immobilized synthetic Aβ dimer assemblies, including synaptotoxic protofibrils, and targeted these conformers in solution. Importantly, NAbs also recognized Aβ extracted from the water-soluble phase of human AD brain, including species that migrated on denaturing PAGE as SDS-stable dimers. The critical reliance on Aβ's conformational state for NAb binding, and not a linear sequence epitope, was confirmed by the antibody's nM reactivity with plate-immobilized protofibrills, and weak uM binding to synthetic Aβ monomers and peptide fragments. The antibody's lack of reactivity against a linear sequence epitope was confirmed by our ability to isolate anti-Aβ NAbs from intravenous immunoglobulin using affinity matrices, immunoglobulin light chain fibrils and Cibacron blue, which had no sequence similarity with the peptide. These findings suggest that further investigations on the molecular basis and the therapeutic/diagnostic potential of anti-Aβ NAbs are warranted.
Collapse
Affiliation(s)
- Alfred T. Welzel
- The Conway Institute, University College Dublin, Belfield, Dublin, Republic of Ireland
| | - Angela D. Williams
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Helen P. McWilliams-Koeppen
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Luis Acero
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | | | - Veronika Blinder
- The Laboratory of Neurodegenerative Research, Brigham and Women’s Hospital, Harvard Institutes of Medicine, Boston, Massachusetts, United States of America
| | - Alex Mably
- The Conway Institute, University College Dublin, Belfield, Dublin, Republic of Ireland
- The Laboratory of Neurodegenerative Research, Brigham and Women’s Hospital, Harvard Institutes of Medicine, Boston, Massachusetts, United States of America
| | | | | | - Michael A. Farrell
- Dublin Brain Bank, Pathology Department, Beaumont Hospital, Dublin, Ireland
| | | | | | - Dominic M. Walsh
- The Conway Institute, University College Dublin, Belfield, Dublin, Republic of Ireland
- The Laboratory of Neurodegenerative Research, Brigham and Women’s Hospital, Harvard Institutes of Medicine, Boston, Massachusetts, United States of America
| | - Alan Solomon
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Brian O’Nuallain
- The Conway Institute, University College Dublin, Belfield, Dublin, Republic of Ireland
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
- The Laboratory of Neurodegenerative Research, Brigham and Women’s Hospital, Harvard Institutes of Medicine, Boston, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
55
|
McCleery J, Molena EJ, Worrall RE. Passive immunisation with monoclonal anti-Abeta antibodies for the treatment of Alzheimer's disease. Hippokratia 2012. [DOI: 10.1002/14651858.cd010188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jenny McCleery
- University of Oxford; Cochrane Dementia and Cognitive Improvement Group; John Radcliffe Hospital Level 4, Main Hospital, Room 4401c Oxford Oxfordshire UK OX39DU
| | - Emma J Molena
- Oxford University Medical School; Wadham College Parks Road Oxford UK OX13PN
| | - Rosie E Worrall
- Oxford University Medical School; Wadham College Parks Road Oxford UK OX13PN
| |
Collapse
|
56
|
Vanderstichele H, Stoops E, Vanmechelen E, Jeromin A. Potential sources of interference on Abeta immunoassays in biological samples. ALZHEIMERS RESEARCH & THERAPY 2012; 4:39. [PMID: 23082750 PMCID: PMC3580396 DOI: 10.1186/alzrt142] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Therapeutic products that depend on the use of an in vitro diagnostic biomarker test to confirm their effectiveness are increasingly being developed. Use of biomarkers is particularly meaningful in the context of selecting the patient population where the therapeutic treatment is believed to be efficacious (patient enrichment). Currently available 'research-use-only' assays for Alzheimer's disease diagnosis all suffer from non-analyte and analyte-specific interferences. The impact of these interferences on the outcome of the assays is not well understood. The confounding factors are hampering correct value determination in biological samples and are intrinsic to the assay concept, the assay design, the presence in the sample of heterophilic antibodies and auto-antibodies, or might be the result of the therapeutic approach. This review focuses on the importance of assay interferences and considers how these might be minimized with the final aim of making the assays more acceptable as in vitro diagnostic biomarker tests for theranostic use.
Collapse
Affiliation(s)
| | - Erik Stoops
- ADxNeurosciences, Technologiepark 4, 9052, Gent, Belgium
| | | | | |
Collapse
|
57
|
Novaretti MCZ, Dinardo CL. Clinical applications of immunoglobulin: update. Rev Bras Hematol Hemoter 2012; 33:221-30. [PMID: 23049300 PMCID: PMC3415732 DOI: 10.5581/1516-8484.20110058] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 03/28/2011] [Indexed: 11/27/2022] Open
Abstract
Human immunoglobulin is the most used blood product in the clinical practice. Immunoglobulin applications have increased quickly since the elucidation of its immunomodulatory and antiinflammatory properties which turned this blood product into a precious tool in the treatment of numerous diseases that present with humoral immune deficiency or that cause immune system dysfunction. Currently, the approved indications for Ig are: primary immunodeficiencies, secondary immunodeficiencies (multiple myeloma or chronic lymphoid leukemia), Kawasaki syndrome, immune thrombocytopenic purpura, Guillain Barré syndrome, graft-versus-host disease following bone marrow transplantation and repeat infections in HIV children. On the other hand, there are numerous "off-label" indications of immunoglobulin, which represent 20-60% of all clinical applications of this drug. It is important to study all these indications and, above all, the scientific evidence for its use, in order to provide patients with a new therapeutic option without burdening the health system. This review results from a wide selection of papers identified in the Pubmed and Lilacs scientific electronic databases. A group of descriptors were used from human immunoglobulin to the names of each disease that immunoglobulin is clinically applied. Our main objective is to list the numerous indications of immunoglobulin, both authorized and "off-label" and to analyze these indications in the light of the most recent scientific evidence.
Collapse
|
58
|
Impact of intravenous immunoglobulin on the dopaminergic system and immune response in the acute MPTP mouse model of Parkinson's disease. J Neuroinflammation 2012; 9:234. [PMID: 23046563 PMCID: PMC3520736 DOI: 10.1186/1742-2094-9-234] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 09/16/2012] [Indexed: 01/19/2023] Open
Abstract
Intravenous immunoglobulin (IVIg) is a blood-derived product, used for the treatment of immunodeficiency and autoimmune diseases. Since a range of immunotherapies have recently been proposed as a therapeutic strategy for Parkinson’s disease (PD), we investigated the effects of an IVIg treatment in a neurotoxin-induced animal model of PD. Mice received four injections of MPTP (15 mg/kg) at 2-hour intervals followed by a 14-day IVIg treatment, which induced key immune-related changes such as increased regulatory T-cell population and decreased CD4+/CD8+ ratio. The MPTP treatment induced significant 80% and 84% decreases of striatal dopamine concentrations (P < 0.01), as well as 33% and 40% reductions in the number of nigral dopaminergic neurons (P < 0.001) in controls and IVIg-treated mice, respectively. Two-way analyses of variance further revealed lower striatal tyrosine hydroxylase protein levels, striatal homovanillic acid concentrations and nigral dopaminergic neurons (P < 0.05) in IVIg-treated animals. Collectively, our results fail to support a neurorestorative effect of IVIg on the nigrostriatal system in the MPTP-treated mice and even suggest a trend toward a detrimental effect of IVIg on the dopaminergic system. These preclinical data underscore the need to proceed with caution before initiating clinical trials of IVIg in PD patients.
Collapse
|
59
|
Sagare AP, Bell RD, Zlokovic BV. Neurovascular dysfunction and faulty amyloid β-peptide clearance in Alzheimer disease. Cold Spring Harb Perspect Med 2012; 2:cshperspect.a011452. [PMID: 23028132 DOI: 10.1101/cshperspect.a011452] [Citation(s) in RCA: 172] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neurovascular dysfunction is an integral part of Alzheimer disease (AD). Changes in the brain vascular system may contribute in a significant way to the onset and progression of cognitive decline and the development of a chronic neurodegenerative process associated with accumulation of amyloid β-peptide (Aβ) in brain and cerebral vessels in AD individuals and AD animal models. Here, we review the role of the neurovascular unit and molecular mechanisms in cerebral vascular cells behind the pathogenesis of AD. In particular, we focus on blood-brain barrier (BBB) dysfunction, decreased cerebral blood flow, and impaired vascular clearance of Aβ from brain. The data reviewed here support an essential role of the neurovascular and BBB mechanisms in AD pathogenesis.
Collapse
Affiliation(s)
- Abhay P Sagare
- Center for Neurodegenerative and Vascular Brain Disorders and Interdisciplinary Program in Dementia Research, Arthur Kornberg Medical Research Building, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, USA
| | | | | |
Collapse
|
60
|
Maftei M, Thurm F, Leirer VM, von Arnim CAF, Elbert T, Przybylski M, Kolassa IT, Manea M. Antigen-bound and free β-amyloid autoantibodies in serum of healthy adults. PLoS One 2012; 7:e44516. [PMID: 22973459 PMCID: PMC3433427 DOI: 10.1371/journal.pone.0044516] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Accepted: 08/08/2012] [Indexed: 12/25/2022] Open
Abstract
Physiological β-amyloid autoantibodies (Aβ-autoantibodies) are currently investigated as potential diagnostic and therapeutic tools for Alzheimer's disease (AD). In previous studies, their determination in serum and cerebrospinal fluid (CSF) using indirect ELISA has provided controversial results, which may be due to the presence of preformed Aβ antigen-antibody immune complexes. Based on the epitope specificity of the Aβ-autoantibodies, recently elucidated in our laboratory, we developed (a) a sandwich ELISA for the determination of circulating Aβ-IgG immune complexes and (b) an indirect ELISA for the determination of free Aβ-autoantibodies. This methodology was applied to the analysis of serum samples from healthy individuals within the age range of 18 to 89 years. Neuropsychological examination of the participants in this study indicated non-pathological, age-related cognitive decline, revealed especially by tests of visual memory and executive function, as well as speed-related tasks. The ELISA serum determinations showed significantly higher levels of Aβ-IgG immune complexes compared to free Aβ-autoantibodies, while no correlation with age or cognitive performance of the participants was found.
Collapse
Affiliation(s)
- Madalina Maftei
- Laboratory of Analytical Chemistry and Biopolymer Structure Analysis, Department of Chemistry, University of Konstanz, Konstanz, Germany
- Steinbeis Research Center for Biopolymer Analysis, University of Konstanz, Konstanz, Germany
| | - Franka Thurm
- Department of Psychology, University of Konstanz, Konstanz, Germany
- Clinical and Biological Psychology, Institute of Psychology and Education, University of Ulm, Ulm, Germany
| | | | | | - Thomas Elbert
- Department of Psychology, University of Konstanz, Konstanz, Germany
| | - Michael Przybylski
- Laboratory of Analytical Chemistry and Biopolymer Structure Analysis, Department of Chemistry, University of Konstanz, Konstanz, Germany
| | - Iris-Tatjana Kolassa
- Department of Psychology, University of Konstanz, Konstanz, Germany
- Clinical and Biological Psychology, Institute of Psychology and Education, University of Ulm, Ulm, Germany
- Zukunftskolleg, University of Konstanz, Konstanz, Germany
| | - Marilena Manea
- Laboratory of Analytical Chemistry and Biopolymer Structure Analysis, Department of Chemistry, University of Konstanz, Konstanz, Germany
- Zukunftskolleg, University of Konstanz, Konstanz, Germany
| |
Collapse
|
61
|
|
62
|
Salomone S, Caraci F, Leggio GM, Fedotova J, Drago F. New pharmacological strategies for treatment of Alzheimer's disease: focus on disease modifying drugs. Br J Clin Pharmacol 2012; 73:504-17. [PMID: 22035455 DOI: 10.1111/j.1365-2125.2011.04134.x] [Citation(s) in RCA: 202] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Current approved drug treatments for Alzheimer disease (AD) include cholinesterase inhibitors (donepezil, rivastigmine, galantamine) and the NMDA receptor antagonist memantine. These drugs provide symptomatic relief but poorly affect the progression of the disease. Drug discovery has been directed, in the last 10 years, to develop 'disease modifying drugs' hopefully able to counteract the progression of AD. Because in a chronic, slow progressing pathological process, such as AD, an early start of treatment enhances the chance of success, it is crucial to have biomarkers for early detection of AD-related brain dysfunction, usable before clinical onset. Reliable early biomarkers need therefore to be prospectively tested for predictive accuracy, with specific cut off values validated in clinical practice. Disease modifying drugs developed so far include drugs to reduce β amyloid (Aβ) production, drugs to prevent Aβ aggregation, drugs to promote Aβ clearance, drugs targeting tau phosphorylation and assembly and other approaches. Unfortunately none of these drugs has demonstrated efficacy in phase 3 studies. The failure of clinical trials with disease modifying drugs raises a number of questions, spanning from methodological flaws to fundamental understanding of AD pathophysiology and biology. Recently, new diagnostic criteria applicable to presymptomatic stages of AD have been published. These new criteria may impact on drug development, such that future trials on disease modifying drugs will include populations susceptible to AD, before clinical onset. Specific problems with completed trials and hopes with ongoing trials are discussed in this review.
Collapse
Affiliation(s)
- Salvatore Salomone
- Department of Clinical and Molecular Biomedicine, Section of Pharmacology and Biochemistry Department of Formative Processes, University of Catania, Viale Andrea Doria 6, Catania, Italy
| | | | | | | | | |
Collapse
|
63
|
Anti-Aβ-MAb and dually decorated nanoliposomes: Effect of Aβ1-42 peptides on interaction with hCMEC/D3 cells. Eur J Pharm Biopharm 2012; 81:49-56. [DOI: 10.1016/j.ejpb.2012.02.006] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 02/09/2012] [Accepted: 02/10/2012] [Indexed: 11/18/2022]
|
64
|
Tayeb HO, Yang HD, Price BH, Tarazi FI. Pharmacotherapies for Alzheimer's disease: Beyond cholinesterase inhibitors. Pharmacol Ther 2012; 134:8-25. [DOI: 10.1016/j.pharmthera.2011.12.002] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 11/21/2011] [Indexed: 12/31/2022]
|
65
|
Wei X, Roettger Y, Tan B, He Y, Dodel R, Hampel H, Wei G, Haney J, Gu H, Johnstone BH, Liu J, Farlow MR, Du Y. Human anti-prion antibodies block prion peptide fibril formation and neurotoxicity. J Biol Chem 2012; 287:12858-66. [PMID: 22362783 DOI: 10.1074/jbc.m111.255836] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Prion diseases are a group of rare, fatal neurodegenerative disorders associated with a conformational transformation of the cellular prion protein (PrP(C)) into a self-replicating and proteinase K-resistant conformer, termed scrapie PrP (PrP(Sc)). Aggregates of PrP(Sc) deposited around neurons lead to neuropathological alterations. Currently, there is no effective treatment for these fatal illnesses; thus, the development of an effective therapy is a priority. PrP peptide-based ELISA assay methods were developed for detection and immunoaffinity chromatography capture was developed for purification of naturally occurring PrP peptide autoantibodies present in human CSF, individual donor serum, and commercial preparations of pooled intravenous immunoglobulin (IVIg). The ratio of anti-PrP autoantibodies (PrP-AA) to total IgG was ∼1:1200. The binding epitope of purified PrP-AA was mapped to an N-terminal region comprising the PrP amino acid sequence KTNMK. Purified PrP-AA potently blocked fibril formation by a toxic 21-amino acid fragment of the PrP peptide containing the amino acid alanine to valine substitution corresponding to position 117 of the full-length peptide (A117V). Furthermore, PrP-AA attenuated the neurotoxicity of PrP(A117V) and wild-type peptides in rat cerebellar granule neuron (CGN) cultures. In contrast, IgG preparations depleted of PrP-AA had little effect on PrP fibril formation or PrP neurotoxicity. The specificity of PrP-AA was demonstrated by immunoprecipitating PrP protein in brain tissues of transgenic mice expressing the human PrP(A117V) epitope and Sc237 hamster. Based on these intriguing findings, it is suggested that human PrP-AA may be useful for interfering with the pathogenic effects of pathogenic prion proteins and, thereby has the potential to be an effective means for preventing or attenuating human prion disease progression.
Collapse
Affiliation(s)
- Xing Wei
- Department of Neurology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
66
|
Lobello K, Ryan JM, Liu E, Rippon G, Black R. Targeting Beta amyloid: a clinical review of immunotherapeutic approaches in Alzheimer's disease. Int J Alzheimers Dis 2012; 2012:628070. [PMID: 22292124 PMCID: PMC3265072 DOI: 10.1155/2012/628070] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 09/21/2011] [Indexed: 12/14/2022] Open
Abstract
As the societal and economic burdens of Alzheimer's disease (AD) continue to mount, so does the need for therapies that slow the progression of the illness. Beta amyloid has long been recognized as the pathologic hallmark of AD, and the past decade has seen significant progress in the development of various immunotherapeutic approaches targeting beta amyloid. This paper reviews active and passive approaches aimed at beta amyloid, with a focus on clinical trial data.
Collapse
Affiliation(s)
- Kasia Lobello
- Department of Clinical Sciences, Pfizer Inc., Collegeville, PA 19426, USA
| | - J. Michael Ryan
- Department of Clinical Sciences, Pfizer Inc., Collegeville, PA 19426, USA
| | - Enchi Liu
- Janssen Alzheimer Immunotherapy Research & Development, LLC., South San Francisco, CA 94080, USA
| | - Gregory Rippon
- Department of Clinical Sciences, Pfizer Inc., Collegeville, PA 19426, USA
| | - Ronald Black
- Department of Clinical Sciences, Pfizer Inc., Collegeville, PA 19426, USA
| |
Collapse
|
67
|
Bach JP, Dodel R. Naturally occurring autoantibodies against β-Amyloid. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 750:91-9. [PMID: 22903668 DOI: 10.1007/978-1-4614-3461-0_7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Naturally occurring antibodies (NAbs) have been described for more than 30 years. Recently, NAbs against β-Amyloid and against other proteins involved in neurodegenerative disorders have been detected in humans. Based on the current evidence, it is hypothesized that anti-Aβ NAbs can inhibit the fibrillation and toxicity of β-aymloid, can improve cognition in a transgenic mouse model and interfere with oligomers of Aβ. Different functions of these NAbs have been described in the current literature. Based on the results of the diverse studies a Phase-III study using IVIG has been initiated in patients with AD. The results will show whether the application of NAbs will change the fate of the disease. This chapter summarizes our current knowledge on NAbs against Aβ.
Collapse
|
68
|
Maudsley S, Chadwick W. Progressive and unconventional pharmacotherapeutic approaches to Alzheimer's disease therapy. Curr Alzheimer Res 2012; 9:1-4. [PMID: 22329648 PMCID: PMC5915359 DOI: 10.2174/156720512799015082] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
69
|
Bansal A, Bajardeen B, Thum M. The basis and value of currently used immunomodulatory therapies in recurrent miscarriage. J Reprod Immunol 2012; 93:41-51. [DOI: 10.1016/j.jri.2011.10.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Revised: 10/25/2011] [Accepted: 10/27/2011] [Indexed: 10/14/2022]
|
70
|
Sardi F, Fassina L, Venturini L, Inguscio M, Guerriero F, Rolfo E, Ricevuti G. Alzheimer's disease, autoimmunity and inflammation. The good, the bad and the ugly. Autoimmun Rev 2011; 11:149-53. [DOI: 10.1016/j.autrev.2011.09.005] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 09/19/2011] [Indexed: 11/26/2022]
|
71
|
Delrieu J, Ousset PJ, Caillaud C, Vellas B. ‘Clinical trials in Alzheimer’s disease’: immunotherapy approaches. J Neurochem 2011; 120 Suppl 1:186-193. [DOI: 10.1111/j.1471-4159.2011.07458.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
72
|
Galimberti D, Scarpini E. Disease-modifying treatments for Alzheimer's disease. Ther Adv Neurol Disord 2011; 4:203-16. [PMID: 21765871 DOI: 10.1177/1756285611404470] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The first drugs developed for Alzheimer's disease (AD), acetylcholinesterase inhibitors (AChEI), increase acetylcholine levels, previously demonstrated to be reduced in AD. To date, four AChEI are approved for the treatment of mild-to-moderate AD. A further therapeutic option available for moderate-to-severe AD is memantine. These treatments are symptomatic, whereas drugs under development are intended to modify the pathological steps leading to AD, thus acting on the evolution of the disease. For this reason they are have been termed 'disease-modifying' drugs. To block the progression of the disease they have to interfere with the pathogenic steps responsible for the clinical symptoms, including the deposition of extracellular amyloid beta (Aβ) plaques and of intracellular neurofibrillary tangles, inflammation, oxidative damage, iron deregulation and cholesterol metabolism. In this review, new perspectives will be discussed. In particular, several approaches will be described, including interference with Aβ deposition by anti-Aβ aggregation agents, vaccination, γ-secretase inhibitors or selective Aβ-lowering agents; interference with tau deposition by methylthioninium chloride; and reduction of inflammation and oxidative damage.
Collapse
Affiliation(s)
- Daniela Galimberti
- Department of Neurological Sciences, 'Dino Ferrari' Center, University of Milan, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Via F. Sforza 35, 20122, Milan, Italy
| | | |
Collapse
|
73
|
Massoud F, Léger GC. Pharmacological treatment of Alzheimer disease. CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 2011; 56:579-88. [PMID: 22014690 DOI: 10.1177/070674371105601003] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVE To review the different pharmacological approaches to the cognitive, functional, and behavioural manifestations of Alzheimer disease (AD). METHODS We searched and critically analyzed the most recent relevant literature on pharmacological treatment of AD. RESULTS The current pharmacological approach to AD treatment is based on vascular prevention and symptomatic therapy with cholinesterase inhibitors (ChEIs) and memantine, an N-methyl-d-aspartic acid antagonist. Clinical trials of 6- to 12-month duration have shown statistically significant benefits with ChEIs and memantine on cognitive, global, functional, and behavioural outcome measures. In general, these benefits are modest. However, they are dose-dependent and reproducible across studies. Most importantly, these benefits are symptomatic as they do not alter disease course. According to the third Canadian Consensus Conference on the Diagnosis and Treatment of Dementia, these agents are considered standard treatment options in AD. We will discuss practical issues related to current pharmacological management, such as setting realistic expectations, management of side effects, switching ChEIs, and the decision to discontinue treatment. The results of clinical trials studying potentially disease-modifying approaches in AD will also be reviewed. Unfortunately, although there remains much promise and enthusiasm, none of these agents has shown consistent benefits, and none are available for use in clinical practice. CONCLUSION Pharmacological options are presently available for the symptomatic treatment of AD. These treatments provide mild but sustained benefits. Before disease-modifying approaches become available, optimizing the use of the available treatment options is crucial.
Collapse
Affiliation(s)
- Fadi Massoud
- Internist-Geriatrician, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montreal, Quebec.
| | | |
Collapse
|
74
|
Klaver AC, Coffey MP, Smith LM, Bennett DA, Finke JM, Dang L, Loeffler DA. ELISA measurement of specific non-antigen-bound antibodies to Aβ1-42 monomer and soluble oligomers in sera from Alzheimer's disease, mild cognitively impaired, and noncognitively impaired subjects. J Neuroinflammation 2011; 8:93. [PMID: 21827691 PMCID: PMC3162899 DOI: 10.1186/1742-2094-8-93] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 08/09/2011] [Indexed: 12/31/2022] Open
Abstract
Background The literature contains conflicting results regarding the status of serum anti-Aβ antibody concentrations in Alzheimer's disease (AD). Reduced levels of these antibodies have been suggested to contribute to the development of this disorder. The conflicting results may be due to polyvalent antibodies, antibody "masking" due to Aβ binding, methodological differences, and/or small sample sizes. The objectives of this pilot study were to compare serum anti-Aβ antibody concentrations between AD, mild cognitive impairment (MCI), and elderly noncognitively impaired (NCI) subjects while addressing these issues, and to perform power analyses to determine appropriate group sizes for future studies employing this approach. Methods Serum antibodies to Aβ1-42 monomer and soluble oligomers in AD, MCI, and NCI subjects (10/group) were measured by ELISA, subtracting polyvalent antibody binding and dissociating antibody-antigen complexes. Differences in mean antibody levels were assessed for significance with repeated measures ANOVA using restricted maximum likelihood estimation, using Tukey-Kramer tests and confidence intervals for multiple comparisons. Spearman's rank correlation was used to determine associations between anti-monomer and anti-oligomer antibody concentrations. Estimated sample sizes required to detect effects of various sizes were calculated. Results There were no significant differences between groups for mean anti-Aβ antibody levels, although these tended to be higher in AD than NCI specimens. Estimated group sizes of 328 and 150 for anti-Aβ monomer and oligomer antibodies, respectively, would have been required for 80% power for significance at 0.05 for a 25% increase in the AD mean relative to the NCI mean. Serum antibody concentrations to Aβ monomer and oligomers were strongly associated (correlations: 0.798 for undissociated sera, 0.564 for dissociated sera). Antibody-antigen dissociation significantly increased anti-Aβ monomer but not anti-Aβ oligomer antibody levels. Conclusions The findings in this pilot study are consistent with relatively similar concentrations of specific, non-antigen-bound antibodies to Aβ1-42 monomer and soluble oligomers in AD, MCI, and NCI sera. The differences between groups for these antibodies would have required approximate group sizes of 328 and 150, respectively, for a high probability for statistical significance. These findings do not support the hypothesis that reduced levels of anti-Aβ antibodies might contribute to AD's pathogenesis.
Collapse
Affiliation(s)
- Andrea C Klaver
- Department of Neurology Research, William Beaumont Hospital Research Institute, Royal Oak, MI 48073, USA
| | | | | | | | | | | | | |
Collapse
|
75
|
Abstract
INTRODUCTION: Tauopathies, including Alzheimer's disease (AD) and some frontotemporal dementias, are neurodegenerative diseases characterised by pathological lesions comprised of tau protein. There is currently a significant and urgent unmet need for disease-modifying therapies for these conditions and recently attention has turned to tau as a potential target for intervention. AREAS COVERED: Increasing evidence has highlighted pathways associated with tau-mediated neurodegeneration as important targets for drug development. Here, the authors review recently published papers in this area and summarise the genetic and pharmacological approaches that have shown efficacy in reducing tau-associated neurodegeneration. These include the use of agents to prevent abnormal tau processing and increase tau clearance, therapies targeting the immune system, and the manipulation of tau pre-mRNA to modify tau isoform expression. EXPERT OPINION: Several small molecule tau-based treatments are currently being assessed in clinical trials, the outcomes of which are eagerly awaited. Current evidence suggests that therapies targeting tau are likely, at least in part, to form the basis of an effective and safe treatment for Alzheimer's disease and related neurodegenerative disorders in which tau deposition is evident.
Collapse
Affiliation(s)
- Wendy Noble
- MRC Centre for Neurodegeneration Research, Department of Neuroscience (P037), King’s College London, Institute of Psychiatry, De Crespigny Park, London, SE5 8AF, UK. Tel: +44 20 7848 0578.
| | - Amy M. Pooler
- MRC Centre for Neurodegeneration Research, Department of Neuroscience (P037), King’s College London, Institute of Psychiatry, De Crespigny Park, London, SE5 8AF, UK. Tel: +44 (0)20 7848 5375.
| | - Diane P. Hanger
- MRC Centre for Neurodegeneration Research, Department of Neuroscience (P037), King’s College London, Institute of Psychiatry, De Crespigny Park, London, SE5 8AF, UK. Tel: +44 (0)20 7848 0041.
| |
Collapse
|
76
|
Corbo CP, Alonso ADC. Therapeutic targets in Alzheimer's disease and related tauopathies. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 98:47-83. [PMID: 21199770 DOI: 10.1016/b978-0-12-385506-0.00002-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease is a progressive neurodegenerative disease that is characterized histopathologically by the presence of plaques, mainly composed of Abeta amyloid and the tangles, mainly composed of hyperphosphorylated tau. To date, there is no treatment that can reverse the disease, and all the current therapeutics is directed to cope with the symptoms of the disease. Here we describe the efforts dedicated to attack the plaques and, in more detail, the process of neurofibrillary degeneration, linked to the presence of the hyperphosphorylated microtubule associated protein tau. We have identified the different putative targets for therapeutics and the current knowledge on them.
Collapse
Affiliation(s)
- Christopher P Corbo
- College of Staten Island, Program in evelopmental Neuroscience, The Graduate Center, City University of New York (CUNY), Staten Island, New York, USA
| | | |
Collapse
|
77
|
Galimberti D, Scarpini E. Progress in Alzheimer's disease. J Neurol 2011; 259:201-11. [PMID: 21706152 DOI: 10.1007/s00415-011-6145-3] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Revised: 06/08/2011] [Accepted: 06/09/2011] [Indexed: 12/16/2022]
Abstract
After more than one century from Alois Alzheimer and Gaetano Perusini's first report, progress has been made in understanding the pathogenic steps of Alzheimer's disease (AD), as well as in its early diagnosis. This review discusses recent findings leading to the formulation of novel criteria for diagnosis of the disease even in a preclinical phase, by using biological markers. In addition, treatment options will be discussed, with emphasis on new disease-modifying compounds and future trial design suitable to test these drugs in an early phase of the disease.
Collapse
Affiliation(s)
- Daniela Galimberti
- Department of Neurological Sciences, Dino Ferrari Center, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, University of Milan, Via F. Sforza 35, 20122, Milan, Italy.
| | | |
Collapse
|
78
|
Naturally occurring autoantibodies against beta-amyloid: investigating their role in transgenic animal and in vitro models of Alzheimer's disease. J Neurosci 2011; 31:5847-54. [PMID: 21490226 DOI: 10.1523/jneurosci.4401-10.2011] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder primarily affecting regions of the brain responsible for higher cognitive functions. Immunization against β-amyloid (Aβ) in animal models of AD has been shown to be effective on the molecular level but also on the behavioral level. Recently, we reported naturally occurring autoantibodies against Aβ (NAbs-Aβ) being reduced in Alzheimer's disease patients. Here, we further investigated their physiological role: in epitope mapping studies, NAbs-Aβ recognized the mid-/C-terminal end of Aβ and preferentially bound to oligomers but failed to bind to monomers/fibrils. NAbs-Aβ were able to interfere with Aβ peptide toxicity, but NAbs-Aβ did not readily clear senile plaques although early fleecy-like plaques were reduced. Administration of NAbs-Aβ in transgenic mice improved the object location memory significantly, almost reaching performance levels of wild-type control mice. These findings suggest a novel physiological mechanism involving NAbs-Aβ to dispose of proteins or peptides that are prone to forming toxic aggregates.
Collapse
|
79
|
Shah S, Federoff HJ. Therapeutic potential of vaccines for Alzheimer's disease. Immunotherapy 2011; 3:287-98. [PMID: 21322764 DOI: 10.2217/imt.10.94] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The pathological hallmarks of Alzheimer's disease (AD) are amyloid-β (Aβ) plaques and Tau-containing neurofibrillary tangles. Although the relationship between neuronal loss and the presence of plaques/tangles is not well understood, the prevailing Aβ hypothesis posits that excessive accumulation of conformers and assemblies of Aβ protein precedes AD-related dementia and neuronal loss. Consequently, most disease-modifying immunotherapy approaches are directed towards modulating the levels of Aβ. The first AD vaccine clinical trial (AN1792) was suspended after the patients developed meningoencephalitis. In spite of the setback, the trial provided insights to refine development second-generation vaccines, which are attempting to resolve the side effects observed in the trial. This article provides an analysis of these efforts.
Collapse
Affiliation(s)
- Salim Shah
- Georgetown University Medical Center, 4000 Reservoir Road, NW 120 Building D, Washington, DC 20007, USA
| | | |
Collapse
|
80
|
Kayed R, Jackson GR, Estes DM, Barrett ADT. Alzheimers disease: review of emerging treatment role for intravenous immunoglobulins. J Cent Nerv Syst Dis 2011; 3:67-73. [PMID: 23861639 PMCID: PMC3663607 DOI: 10.4137/jcnsd.s5018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common neurodegenerative disorder. Currently available therapies are symptomatic but do not alter underlying disease progression. Immunotherapeutic approaches such as anti Aβ peptide active vaccination trials have had limited success to date. Intravenous immunoblobulin (IVIg) is widely used in immune-mediated neurological disorders such myasthenia gravis and Guillain-Barre syndrome. These preparations have been obtained from the pooled plasma of healthy human donors and contain natural anti-amyloid antibodies and are well tolerated. A small pilot study of passive immunotherapy using IVIg has suggested cognitive improvement. A multicenter phase III trial is ongoing and will determine whether or not this treatment can ameliorate cognitive deficits in mild-to-moderate AD. Here, we briefly review the pathogenic role of amyloid and tau in AD, as well as immunotherapeutic efforts to date. We also summarize what is known about naturally occurring anti-Aβ and tau antibodies in IVIg with a view toward explaining potential mechanisms underlying their therapeutic effects.
Collapse
Affiliation(s)
- Rakez Kayed
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX, USA. ; Department of Neurology, University of Texas Medical Branch, Galveston, TX, USA. ; Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, TX, USA
| | | | | | | |
Collapse
|
81
|
Abstract
INTRODUCTION Alzheimer's disease (AD) is a debilitating neurodegenerative illness affecting over 35 million people worldwide. Solanezumab is a monoclonal antibody that binds to β-amyloid (Aβ), a protein that plays a key role in the pathogenesis of AD. The drug is currently being investigated in Phase III trials as a disease-modifying treatment for AD. AREAS COVERED This paper reviews literature on solanezumab that is available in PubMed from 2008 to 2010, other treatment trials in clinicaltrials.gov and published abstracts from conferences. The article also provides a discussion of the early trials of AN1792 and an overview of the immunotherapies currently in development. The authors provide the reader with a critical appraisal of the to-date clinical trial data on solanezumab and its implications for the broader field of immunotherapies for AD. EXPERT OPINION Solanezumab can neutralize soluble Aβ peptides, which may represent the more neurotoxic of the Aβ species. Phase II findings support the compound's safety, which has been a concern for some Aβ immunotherapies. Cerebrospinal and plasma biomarker changes with solanezumab treatment are encouraging. Results of the ongoing Phase III trials will be instrumental in determining the drug's clinical significance.
Collapse
Affiliation(s)
- Hossein Samadi
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, VA Greater Los Angeles Healthcare System, 760 Westwood Plaza RM C8-193, Los Angeles, CA 90024, USA
| | | |
Collapse
|
82
|
Krishnamurthy PK, Sigurdsson EM. Therapeutic applications of antibodies in non-infectious neurodegenerative diseases. N Biotechnol 2011; 28:511-7. [PMID: 21473943 DOI: 10.1016/j.nbt.2011.03.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease, Huntington's disease (HD) or amyotrophic lateral sclerosis (ALS) are all characterised histologically by the presence of deposits of misfolded proteins, tau and amyloid-β, α-synuclein, huntingtin or superoxide dismutase, respectively. Currently, these illnesses do not have any disease modifying treatment options. A novel therapeutic strategy that is being pursued is immunomodulation, which is using the body's immune system to target the self-proteins that are deposited. Most of these promising approaches are still in preclinical development while some have progressed to Phase III clinical trials. As new insights are gained, it is hoped that these immunotherapies will be effective tools at slowing the progression of these debilitating diseases.
Collapse
Affiliation(s)
- Pavan K Krishnamurthy
- Department of Physiology and Neuroscience, New York University School of Medicine, 550 First Avenue, New York, NY 10016, United States.
| | | |
Collapse
|
83
|
|
84
|
Ji W, Ha I. Drug development for Alzheimer's disease: recent progress. Exp Neurobiol 2010; 19:120-31. [PMID: 22110351 PMCID: PMC3214787 DOI: 10.5607/en.2010.19.3.120] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Accepted: 12/28/2010] [Indexed: 12/31/2022] Open
Abstract
Alzheimer's disease, the most common cause of dementia, is characterized by two major pathological hallmarks: amyloid plaques and neurofibrillary tangles. Based on these two indicators, an amyloid cascade hypothesis was proposed, and accordingly, most current therapeutic approaches are now focused on the removal of β-amyloid peptides (Aβ from the brain. Additionally, strategies for blocking tau hyperphosphorylation and aggregation have been suggested, including the development of drugs that can block the formation of tangles. However, there are no true disease-modifying drugs in the current market, though many drugs based on theories other than Aβ and tau pathology are under development. The purpose of this review was to provide information on the current development of AD drugs and to discuss the issues related to drug development.
Collapse
Affiliation(s)
- Wonjin Ji
- Institute for Brain Science and Technology (IBST)/Graduate Program in Neuroscience, Inje University, Busan 614-735, Korea
| | | |
Collapse
|
85
|
|
86
|
Zlokovic BV, Deane R, Sagare AP, Bell RD, Winkler EA. Low-density lipoprotein receptor-related protein-1: a serial clearance homeostatic mechanism controlling Alzheimer's amyloid β-peptide elimination from the brain. J Neurochem 2010; 115:1077-89. [PMID: 20854368 PMCID: PMC2972355 DOI: 10.1111/j.1471-4159.2010.07002.x] [Citation(s) in RCA: 200] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Low-density lipoprotein receptor-related protein-1 (LRP1), a member of the low-density lipoprotein receptor family, has major roles in the cellular transport of cholesterol, endocytosis of 40 structurally diverse ligands, transcytosis of ligands across the blood-brain barrier, and transmembrane and nuclear signaling. Recent evidence indicates that LRP1 regulates brain and systemic clearance of Alzheimer's disease (AD) amyloid β-peptide (Aβ). According to the two-hit vascular hypothesis for AD, vascular damage precedes cerebrovascular and brain Aβ accumulation (hit 1) which then further amplifies neurovascular dysfunction (hit 2) preceding neurodegeneration. In this study, we discuss the roles of LRP1 during the hit 1 and hit 2 stage of AD pathogenesis and describe a three-level serial LRP1-dependent homeostatic control of Aβ clearance including (i) cell-surface LRP1 at the blood-brain barrier and cerebrovascular cells mediating brain-to-blood Aβ clearance (ii) circulating LRP1 providing a key endogenous peripheral 'sink' activity for plasma Aβ which prevents free Aβ access to the brain, and (iii) LRP1 in the liver mediating systemic Aβ clearance. Pitfalls in experimental Aβ brain clearance measurements with the concurrent use of peptides/proteins such as receptor-associated protein and aprotinin are also discussed. We suggest that LRP1 has a critical role in AD pathogenesis and is an important therapeutic target in AD.
Collapse
Affiliation(s)
- Berislav V Zlokovic
- Center for Neurodegenerative and Vascular Brain Disorders, University of Rochester Medical Center, Rochester, New York 14642,, USA.
| | | | | | | | | |
Collapse
|
87
|
Lindhagen-Persson M, Brännström K, Vestling M, Steinitz M, Olofsson A. Amyloid-β oligomer specificity mediated by the IgM isotype--implications for a specific protective mechanism exerted by endogenous auto-antibodies. PLoS One 2010; 5:e13928. [PMID: 21085663 PMCID: PMC2978096 DOI: 10.1371/journal.pone.0013928] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Accepted: 10/18/2010] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Alzheimers disease (AD) has been strongly linked to an anomalous self-assembly of the amyloid-β peptide (Aβ). The correlation between clinical symptoms of AD and Aβ depositions is, however, weak. Instead small and soluble Aβ oligomers are suggested to exert the major pathological effects. In strong support of this notion, immunological targeting of Aβ oligomers in AD mice-models shows that memory impairments can be restored without affecting the total burden of Aβ deposits. Consequently a specific immunological targeting of Aβ oligomers is of high therapeutic interest. METHODOLOGY/PRINCIPAL FINDINGS Previously the generation of conformational-dependent oligomer specific anti-Aβ antibodies has been described. However, to avoid the difficult task of identifying a molecular architecture only present on oligomers, we have focused on a more general approach based on the hypothesis that all oligomers expose multiple identical epitopes and therefore would have an increased binding to a multivalent receptor. Using the polyvalent IgM immunoglobulin we have developed a monoclonal anti-Aβ antibody (OMAB). OMAB only demonstrates a weak interaction with Aβ monomers and dimers having fast on and off-rate kinetics. However, as an effect of avidity, its interaction with Aβ-oligomers results in a strong complex with an exceptionally slow off-rate. Through this mechanism a selectivity towards Aβ oligomers is acquired and OMAB fully inhibits the cytotoxic effect exerted by Aβ(1-42) at highly substoichiometric ratios. Anti-Aβ auto-antibodies of IgM isotype are frequently present in the sera of humans. Through a screen of endogenous anti-Aβ IgM auto-antibodies from a group of healthy individuals we show that all displays a preference for oligomeric Aβ. CONCLUSIONS/SIGNIFICANCE Taken together we provide a simple and general mechanism for targeting of oligomers without the requirement of conformational-dependent epitopes. In addition, our results suggest that IgM anti-Aβ auto-antibodies may exert a more specific protective mechanism in vivo than previously anticipated.
Collapse
Affiliation(s)
| | | | - Monika Vestling
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Michael Steinitz
- Department of Pathology, Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Anders Olofsson
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| |
Collapse
|
88
|
Journal Watch. Pharmaceut Med 2010. [DOI: 10.1007/bf03256806] [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]
|