101
|
Frenkel D, Dewachter I, Van Leuven F, Solomon B. Reduction of beta-amyloid plaques in brain of transgenic mouse model of Alzheimer's disease by EFRH-phage immunization. Vaccine 2003; 21:1060-5. [PMID: 12559780 DOI: 10.1016/s0264-410x(02)00609-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Antibodies to the epitope EFRH, representing residues 3-6 within the beta-amyloid (Abeta) sequence, were previously shown to affect the solubility and disaggregation of Abeta fibrils in vitro. Here, we describe a novel method of immunization, using as antigen the EFRH peptide displayed on the surface of the filamentous phage. The EFRH phage evoked effective auto-immune antibodies in amyloid precursor protein [V717I] (APP[V717I]) transgenic mice that recapitulate the amyloid plaques and vascular pathology of Alzheimer's disease (AD). The immunization provoked a considerable reduction in the number of Abeta amyloid plaques in the brain of the transgenic mice and may serve as the basis for anti-Abeta vaccine.
Collapse
Affiliation(s)
- Dan Frenkel
- Department of Molecular Microbiology & Biotechnology, The George S Wise Faculty of Life Sciences, Tel-Aviv University, Ramat Aviv, Tel-Aviv 69978, Israel
| | | | | | | |
Collapse
|
102
|
Solomon B, Frenkel D. Generation and brain delivery of anti-aggregating antibodies against beta-amyloid plaques using phage display technology. JOURNAL OF NEURAL TRANSMISSION. SUPPLEMENTUM 2003:321-5. [PMID: 12456075 DOI: 10.1007/978-3-7091-6139-5_30] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Antibodies towards the N-terminal region of the beta-amyloid peptide bind to beta-amyloid fibrils, leading to their disaggregation. We generated anti-aggregating beta-amyloid antibodies using filamentous phages displaying the only four amino acids EFRH found to be the main regulatory site for beta-amyloid formation. In order to overcome the low permeability of the blood brain barrier for targeting 'anti-aggregating' mAbs to the betaA plaques in the brain, we applied antibody engineering methods to minimize the size of the mAbs while maintaining their biological activity. We found that single-chain antibodies displayed on the surface of the phage are capable of entering the central nervous system (CNS). The feasibility of these novel strategies for the production and targeting of anti-aggregating antibodies against beta-amyloid plaques to disease affected regions in the CNS may have clinical potential for treatment of Alzheimer's disease.
Collapse
Affiliation(s)
- B Solomon
- Department of Molecular Microbiology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Israel.
| | | |
Collapse
|
103
|
Abstract
The pathology of Alzheimer's disease (AD) shows a significant correlation between beta-amyloid peptide (AbetaP) conformation and the clinical severity of dementia. For many years, efforts have been focused on the development of inhibitors of beta-amyloid (Abeta) formation and its related neurotoxic effects. The author has developed a new concept showing that site-directed antibodies may modulate formation of Abeta. The performance of anti-Abeta antibodies in transgenic mice models of AD showed that they are delivered to the central nervous system (CNS), preventing in vivo formation of Abeta. Moreover, these antibodies dissolve Abeta plaques and protect the mice from learning difficulties and age-related memory deficits. Experimental active immunisation with Abeta (1-42) in humans has been stopped in Phase II of their clinical trials. However, several new preparations, able to provide antibodies against Abeta by either active or passive routes, have been formulated and at least one of these is likely to reach clinical testing. These data support the hypothesis that AbetaP plays a central role in AD and antibodies which modulate Abeta conformation may lead to immunotherapy of the disease.
Collapse
Affiliation(s)
- Beka Solomon
- Department of Molecular Microbiology & Biotechnology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Ramat Aviv, Tel-Aviv 69978, Israel.
| |
Collapse
|
104
|
Lemere CA, Spooner ET, Leverone JF, Mori C, Clements JD. Intranasal immunotherapy for the treatment of Alzheimer's disease: Escherichia coli LT and LT(R192G) as mucosal adjuvants. Neurobiol Aging 2002; 23:991-1000. [PMID: 12470794 DOI: 10.1016/s0197-4580(02)00127-6] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Alzheimer's disease (AD) is the most common form of dementia worldwide, yet there is currently no effective treatment or cure. Extracellular deposition of amyloid-beta protein (Abeta) in brain is a key neuropathological characteristic of AD. In 1999, Schenk et al. first reported that an injected Abeta vaccine given to PDAPP mice, an AD mouse model displaying Abeta deposition in brain, led to the lowering of Abeta levels in brain. In 2000, we demonstrated that intranasal (i.n.) immunization with human synthetic Abeta1-40 peptide for 7 months led to a 50-60% reduction in cerebral Abeta burden in PDAPP mice; serum Abeta antibody titers were low (approximately 26 microg/ml). More recently, we have optimized our i.n. Abeta immunization protocol in wild-type (WT) mice. When low doses Escherichia coli heat-labile enterotoxin (LT) were given as a mucosal adjuvant with Abeta i.n., there was a dramatic 12-fold increase in Abeta antibody titers in WT B6D2F1 mice treated two times per week for 8 weeks compared to those of mice receiving i.n. Abeta without adjuvant. A non-toxic form of LT, designated LT(R192G), showed even better adjuvanticity; anti-Abeta antibody titers were 16-fold higher than those seen in mice given i.n. Abeta without adjuvant. In both cases, the serum Abeta antibodies recognized epitopes within Abeta1-15 and were of the immunoglobulin (Ig) isotypes IgG2b, IgG1, IgG2a and low levels of IgA. This new and improved Abeta vaccine protocol is now being tested in AD mouse models with the expectation that higher Abeta antibody titers may be more effective in reducing cerebral Abeta levels.
Collapse
Affiliation(s)
- Cynthia A Lemere
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | | | | | | | | |
Collapse
|
105
|
Schenk D. Amyloid-beta immunotherapy for Alzheimer's disease: the end of the beginning. Nat Rev Neurosci 2002; 3:824-8. [PMID: 12360327 DOI: 10.1038/nrn938] [Citation(s) in RCA: 312] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Dale Schenk
- Elan Pharmaceuticals, 800 Gateway Boulevard, South San Francisco, California 94080, USA.
| |
Collapse
|
106
|
Wang Y, Klunk WE, Huang GF, Debnath ML, Holt DP, Mathis CA. Synthesis and evaluation of 2-(3'-iodo-4'-aminophenyl)-6-hydroxybenzothiazole for in vivo quantitation of amyloid deposits in Alzheimer's disease. J Mol Neurosci 2002; 19:11-6. [PMID: 12212766 DOI: 10.1007/s12031-002-0004-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2001] [Accepted: 10/16/2001] [Indexed: 11/26/2022]
Abstract
A potent and brain permeable amyloid ligand has been identified as a lead compound capable of I-123/125-labelling for single photon emission computed tomography (SPECT) imaging. In this study, we report the synthesis and I-125-radiolabelling of Compound 6 and its in vitro and in vivo properties. Compound 6 [2-(3'-iodo-4'-aminophenyl)-6-hydroxybenzothiazole] bound to synthetic A beta(1-40) fibrils in a saturable manner, exhibiting an affinity (Ki) of 11+/-1.1 nM in a competitive binding assay using a tritiated thioflavin T analog ([3H]BTA-1) as radioligand. [125I]6 binding to synthetic A beta(1-40) fibrils fit a single-site model. [125I]6 exhibited several-fold higher binding to homogenates of frontal cortex from post-mortem Alzheimer's disease brain relative to age-matched control brain homogenates. No difference in binding was observed in cerebellum. The ratio of radioactivity concentration between frontal cortex and cerebellum was 6-fold higher in AD brain homogenates than the age-matched control. [125I]6 also readily penetrated the blood-brain barrier in normal control mice with an average radioactivity concentration of 6.43+/-0.62%ID/g detected in the whole brain at 2 min post i.v. injection. At 30 min, the radioactivity concentration decreased to 0.40+/-0.05%ID/g, indicating good clearance in the absence of amyloid deposits in the brain.
Collapse
Affiliation(s)
- Yanming Wang
- PET Facility, Department of Radiology, School of Medicine, University of Pittsburgh, PA 15213, USA.
| | | | | | | | | | | |
Collapse
|
107
|
Morgan C, Bugueño MP, Garrido J, Inestrosa NC. Laminin affects polymerization, depolymerization and neurotoxicity of Abeta peptide. Peptides 2002; 23:1229-40. [PMID: 12128080 DOI: 10.1016/s0196-9781(02)00058-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Amyloid deposition in Alzheimer fibrils forms neurotoxic senile plaques in a process that may be modulated by associated proteins. In this work we demonstrate the ability of laminin-1 and laminin-2 to inhibit fibril formation and toxicity on cultured rat hippocampal neurons. We confirm that the laminin-1-derived peptide YFQRYLI inhibits efficiently both fibril formation and neurotoxicity and show that the IKVAV peptide inhibits amyloid neurotoxicity despite its slight inhibition of fibril formation. On other hand, laminin-1 induces disaggregation of preformed fibrils in vitro, characterized as a progressive disassembly of fibrils into protofibrils and further clearance of these latter species, leading to a continual inhibition of amyloid neurotoxicity.
Collapse
Affiliation(s)
- Carlos Morgan
- Departamento de Biología Celular y Molecular, MIFAB, Facultad de Ciencias Biológicas, Centro de Regulación Celular y Patología, Pontificia Universidad Católica de Chile, Casilla 114-D, Santiago, Chile
| | | | | | | |
Collapse
|
108
|
Bergamaschini L, Donarini C, Rossi E, De Luigi A, Vergani C, De Simoni MG. Heparin attenuates cytotoxic and inflammatory activity of Alzheimer amyloid-beta in vitro. Neurobiol Aging 2002; 23:531-6. [PMID: 12009502 DOI: 10.1016/s0197-4580(02)00003-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Amyloid-beta protein (Abeta) is implicated in the pathogenesis of Alzheimer's disease because of its neurotoxicity and the ability to trigger local inflammation. Compounds that interact with the amino acids of the N-terminal region or interfere with aggregation can reduce the Abeta biologic activity. We evaluated the effect of heparin on Abeta (1-42) neurotoxicity and on its ability to activate complement and contact system. On differentiated PC12 cells, a reliable model of neuronal cells, heparin at the doses of 10 and 20 microg/ml significantly counteracted Abeta cytotoxicity as assessed by measuring MTT conversion. We then explored the effect of heparin on Abeta (1-42)-induced complement and contact system activation. Abeta (1-42) was incubated with heparin in presence of normal plasma as the source of complement and contact system factors. Heparin reduced, in a dose-dependent manner, complement and contact system activation, assessed by measuring the degree of C4 and high molecular weight kininogen cleavage. The present data show that heparin can attenuate neurotoxic and pro-inflammatory activity of Abeta and suggest that this drug could represent a new strategy to reduce the progressive neurodegeneration in AD.
Collapse
Affiliation(s)
- Luigi Bergamaschini
- Department of Internal Medicine, Ospedale Maggiore IRCCS, University of Milan, Italy.
| | | | | | | | | | | |
Collapse
|
109
|
Abstract
Vaccines are by definition prophylactic, but in recent years an interest has developed in therapeutic vaccines for infectious diseases such as AIDS and tuberculosis, as well as gastric ulcers, cancer (with different approaches to combat various types of malignancy) and autoimmune diseases (a definite success was the development of a vaccine against multiple sclerosis) and there are potential vaccines in development for myasthenia gravis, lupus and diabetes. Therapeutic vaccines are also being developed against cognitive diseases such as Alzheimer's disease, prion diseases and Huntington's disease. All of these efforts are based on the therapeutic vaccine being closely related chemically to the etiological agent that causes the disease.
Collapse
Affiliation(s)
- Michael Sela
- Department of Immunology, Weizmann Institute of Science, Rehovot 76100, Israel.
| | | | | |
Collapse
|
110
|
|
111
|
|
112
|
Halliwell B. Role of free radicals in the neurodegenerative diseases: therapeutic implications for antioxidant treatment. Drugs Aging 2002; 18:685-716. [PMID: 11599635 DOI: 10.2165/00002512-200118090-00004] [Citation(s) in RCA: 1011] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Free radicals and other so-called 'reactive species' are constantly produced in the brain in vivo. Some arise by 'accidents of chemistry', an example of which may be the leakage of electrons from the mitochondrial electron transport chain to generate superoxide radical (O2*-). Others are generated for useful purposes, such as the role of nitric oxide in neurotransmission and the production of O2*- by activated microglia. Because of its high ATP demand, the brain consumes O2 rapidly, and is thus susceptible to interference with mitochondrial function, which can in turn lead to increased O2*- formation. The brain contains multiple antioxidant defences, of which the mitochondrial manganese-containing superoxide dismutase and reduced glutathione seem especially important. Iron is a powerful promoter of free radical damage, able to catalyse generation of highly reactive hydroxyl, alkoxyl and peroxyl radicals from hydrogen peroxide and lipid peroxides, respectively. Although most iron in the brain is stored in ferritin, 'catalytic' iron is readily mobilised from injured brain tissue. Increased levels of oxidative damage to DNA, lipids and proteins have been detected by a range of assays in post-mortem tissues from patients with Parkinson's disease, Alzheimer's disease and amyotrophic lateral sclerosis, and at least some of these changes may occur early in disease progression. The accumulation and precipitation of proteins that occur in these diseases may be aggravated by oxidative damage, and may in turn cause more oxidative damage by interfering with the function of the proteasome. Indeed, it has been shown that proteasomal inhibition increases levels of oxidative damage not only to proteins but also to other biomolecules. Hence, there are many attempts to develop antioxidants that can cross the blood-brain barrier and decrease oxidative damage. Natural antioxidants such as vitamin E (tocopherol), carotenoids and flavonoids do not readily enter the brain in the adult, and the lazaroid antioxidant tirilazad (U-74006F) appears to localise in the blood-brain barrier. Other antioxidants under development include modified spin traps and low molecular mass scavengers of O2*-. One possible source of lead compounds is the use of traditional remedies claimed to improve brain function. Little is known about the impact of dietary antioxidants upon the development and progression of neurodegenerative diseases, especially Alzheimer's disease. Several agents already in therapeutic use might exert some of their effects by antioxidant action, including selegiline (deprenyl), apomorphine and nitecapone.
Collapse
Affiliation(s)
- B Halliwell
- Department of Biochemistry, Faculty of Medicine, National University of Singapore, Singapore.
| |
Collapse
|
113
|
Ermolenko DN, Zherdev AV, Dzantiev BB, Popov VO. Antiperoxidase antibodies enhance refolding of horseradish peroxidase. Biochem Biophys Res Commun 2002; 291:959-65. [PMID: 11866459 DOI: 10.1006/bbrc.2002.6544] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effect of monoclonal antibodies on protein folding was studied using horseradish peroxidase refolding from guanidine hydrochloride as a model process. Among the five antiperoxidase clones tested, one was found to increase the yield of catalytically active peroxidase after guanidine treatment. The same clone also increased the activity of the native peroxidase by a factor of 2-2.5. While peroxidase refolding under standard conditions resulted in the recovery of only 7-8% of the initial catalytic activity, antibody-assisted refolding increased the yield to 50-100% (or 20-40% from the activity of native enzyme with antibodies). Kinetics of autorefolding and antibody-assisted refolding differed significantly. In the course of autorefolding the catalytic activity was recovered within the first 2.5 min and did not change further within a 2.5- to 60-min interval, whereas in the course of antibody-assisted refolding maximal catalytic activity was attained only in 60 min. The yield of active peroxidase for the antibody-assisted refolding depended linearly on the antibody concentration. The observed effect was strongly specific. Other antiperoxidase clones tested as well as nonspecific antithyroglobulin antibody affected neither kinetics, no the yield of peroxidase refolding.
Collapse
Affiliation(s)
- D N Ermolenko
- Institute of Biochemistry, Russian Academy of Sciences, Leninsky Prospect 33, 117071 Moscow, Russia
| | | | | | | |
Collapse
|
114
|
Nicolau C, Greferath R, Balaban TS, Lazarte JE, Hopkins RJ. A liposome-based therapeutic vaccine against beta -amyloid plaques on the pancreas of transgenic NORBA mice. Proc Natl Acad Sci U S A 2002; 99:2332-7. [PMID: 11842183 PMCID: PMC122365 DOI: 10.1073/pnas.022627199] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2001] [Accepted: 11/20/2001] [Indexed: 11/18/2022] Open
Abstract
Immune tolerance to beta-amyloid (Abeta) was broken in NORBA transgenic mice presenting Abeta plaques on their pancreases. Vaccination of Black C57, BALB/c, and NORBA mice with the synthetic Abeta(1-16) sequence modified by covalently attaching two palmitoyl residues at each end of the peptide, subsequently reconstituted in liposomes-Lipid A elicited titers of 1:5,000 of anti-Abeta(1-16) antibodies within 10 weeks after the first inoculation. On direct interaction, sera with antibody titers of 1:5,000 solubilized in vitro up to 80% of preformed Abeta(1-42) aggregates. Cryosections of pancreases of unvaccinated NORBA mice show, on staining with Thioflavin T, extensive areas of high-intensity fluorescence in the acinar cell fields. Quantitation of the average fluorescence intensity in each section indicated that: (i) whereas nonvaccinated NORBA mice develop plaques within 45-60 days after birth, vaccinated 8-week-old NORBA mice did not develop amyloid plaques on their pancreases over a period of 7 months; (ii) cryosections from pancreases of 9- and 15-month-old vaccinated NORBA mice showed less than 50% of the fluorescence shown by cryosections from unvaccinated animals of the same age. The results indicate that palmitoylated Abeta peptides, reconstituted in liposomes-lipid A, are highly immunogenic, eliciting "therapeutic" antibody titers within 3 months of the first inoculation and preventing amyloid plaque formation in young animals or significantly reducing existing plaques in older transgenic mice. Possible implications for the therapy of Alzheimer's disease are discussed.
Collapse
Affiliation(s)
- Claude Nicolau
- Ecole Supérieure de Biotechnologie de Strasbourg, Université Louis Pasteur, 67091 Strasbourg, France.
| | | | | | | | | |
Collapse
|
115
|
Molenaar TJM, Michon I, de Haas SAM, van Berkel TJC, Kuiper J, Biessen EAL. Uptake and processing of modified bacteriophage M13 in mice: implications for phage display. Virology 2002; 293:182-91. [PMID: 11853411 DOI: 10.1006/viro.2001.1254] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Internalization and degradation of filamentous bacteriophage M13 by a specific target cell may have major consequences for the recovery of phage in in vivo biopanning of phage libraries. Therefore, we investigated the pharmacokinetics and processing of native and receptor-targeted phage in mice. (35)S-radiolabeled M13 was chemically modified by conjugation of either galactose (lacM13) or succinic acid groups (sucM13) to the coat protein of the phage to stimulate uptake by galactose recognizing hepatic receptors and scavenger receptors, respectively. Receptor-mediated endocytosis of modified phage reduced the plasma half-life of native M13 (t(1/2) = 4.5 h) to 18 min for lactosylated and 1.5 min for succinylated bacterophage. Internalization of sucM13 was complete within 30 min after injection and resulted in up to 5000-fold reduction of bioactive phage within 90 min. In conclusion, these data provide information on the in vivo behavior of wild-type and receptor-targeted M13, which has important implications for future in vivo phage display experiments and for the potential use of M13 as a viral gene delivery vehicle.
Collapse
Affiliation(s)
- Tom J M Molenaar
- Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Sylvius Laboratory, 2300 RA Leiden, The Netherlands
| | | | | | | | | | | |
Collapse
|
116
|
Solomon B. Immunotherapeutic strategies for prevention and treatment of Alzheimer's disease. DNA Cell Biol 2001; 20:697-703. [PMID: 11788047 DOI: 10.1089/10445490152717550] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Pathologic examination in Alzheimer's disease (AD) shows a significant correlation between beta-amyloid peptide (AbetaP) deposition and the clinical severity of dementia. Formation of beta-amyloid (Abeta) is a complex kinetic and thermodynamic process, dependent on peptide-peptide interactions that may be modulated by other proteins. We found that site-directed antibodies toward peptide EFRH sequences 3-6 of the N-terminal region of AbetaP suppress in vitro formation of Abeta and dissolve already-formed fibrillar amyloid. These so-called chaperone-like properties of monoclonal antibodies led to the development of a new immunologic approach to AD treatment. The immunization procedure, based on phages displaying the EFRH epitope as antigen, induced anti-AbetaP antibodies that recognized the whole AbetaP and exhibited antiaggregating properties similar to those of antibodies obtained by injection of Abeta fibrils. Production and performance of anti-beta-amyloid antibodies in the transgenic mouse model of AD showed that these antibodies may be delivered from the periphery to the central nervous system, preventing the formation of Abeta and dissolving already-present aggregates. Moreover, immunization with Abeta protected transgenic mice from the learning and age-related memory deficits that occur in AD. These data support the hypotheses that Abeta plays a central role in AD and that site-directed antibodies that modulate Abeta conformation may provide immunotherapy of the disease.
Collapse
Affiliation(s)
- B Solomon
- Department of Molecular Microbiology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
| |
Collapse
|
117
|
Lemere CA, Maron R, Selkoe DJ, Weiner HL. Nasal vaccination with beta-amyloid peptide for the treatment of Alzheimer's disease. DNA Cell Biol 2001; 20:705-11. [PMID: 11788048 DOI: 10.1089/10445490152717569] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Alzheimer's disease (AD) is a severe neurodegenerative disease for which there is currently no effective prevention or treatment. The prediction that the number of U.S. patients with AD will triple to approximately 14 million over the next 50 years underscores the urgent need to explore novel therapeutic strategies for AD. The beta-amyloid protein (Abeta) accumulation and accompanying inflammation appear to play key roles in initiating the neuronal degeneration that underlies the signs and symptoms of AD. Interventions geared toward reducing Abeta accumulation and inflammatory responses should delay or prevent the onset of the clinical disease. Recently, several research groups, including ours, have shown that vaccination with Abeta results in a significant lowering of the Abeta burden in the brains of APP transgenic mice and, in some studies, improvement in their cognitive deficits. Our study described a novel approach, namely mucosal (intranasal) Abeta vaccination. Precisely how Abeta vaccination chronically lowers Abeta levels and reduces Abeta-associated pathology remains unclear. Here, we provide an overview of these studies, with particular emphasis on our work with intranasal Abeta vaccination. Examples of other intranasal vaccines and mucosal adjuvants are presented. Taken together, these data have implications for the future development of an intranasal Abeta vaccine for humans.
Collapse
Affiliation(s)
- C A Lemere
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
| | | | | | | |
Collapse
|
118
|
Dickey CA, Morgan DG, Kudchodkar S, Weiner DB, Bai Y, Cao C, Gordon MN, Ugen KE. Duration and specificity of humoral immune responses in mice vaccinated with the Alzheimer's disease-associated beta-amyloid 1-42 peptide. DNA Cell Biol 2001; 20:723-9. [PMID: 11788050 DOI: 10.1089/10445490152717587] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by overproduction of beta-amyloid (Abeta), which is formed from amyloid precursor protein (APP), with the subsequent pathologic deposition of Abeta in regions of the brain important for memory and cognition. Recently, vaccination of murine models of AD that exhibit Abeta deposition has halted or delayed the usual progression of the pathology of AD. Our group has demonstrated that vaccination of a doubly transgenic mouse model (expressing mutant APP and presenilin-1) with the Abeta 1-42 peptide protects these mice from the memory deficits they would ordinarily develop. This report further characterizes the Abeta 1-42 peptide vaccine in mice. Anti-Abeta response time course analysis indicated that at least three vaccinations (each 100 microg) were necessary to elicit a significant anti-Abeta titer. Subsequent vaccinations resulted in half-maximal antibody titers of at least 10,000, and these titers were maintained for at least 5 months after the final boost. Peptide binding competition studies indicated that the highest humoral responses are generated against the N terminus of the Abeta peptide. Also, measurement of specific murine Ig isotypes in Abeta-vaccinated mice demonstrated a predominant IgG(1) and IgG(2b) response, suggesting a type 2 (Th2) T-helper cell immune response, which drives humoral immunity. Finally, lymphocyte proliferation assay experiments using Abeta peptides and splenocytes from vaccinated mice demonstrated that the vaccine specifically stimulates T-cell epitopes present within the Abeta peptide.
Collapse
Affiliation(s)
- C A Dickey
- Alzheimer's Research Laboratory, University of South Florida, Tampa, Florida 33612, USA
| | | | | | | | | | | | | | | |
Collapse
|
119
|
Abstract
Beta-amyloid pathology, the main hallmark of Alzheimer's disease (AD), has been linked to its conformational status and aggregation. We recently showed that site-directed monoclonal antibodies (mAbs) towards the N-terminal region of the human beta-amyloid peptide bind to preformed beta-amyloid fibrils (Abeta), leading to disaggregation and inhibition of their neurotoxic effect. Here we report the development of a novel immunization procedure to raise effective anti-aggregating amyloid beta-protein (AbetaP) antibodies, using as antigen filamentous phages displaying the only EFRH peptide found to be the epitope of these antibodies. Due to the high antigenicity of the phage no adjuvant is required to obtain high affinity anti-aggregating IgG antibodies in animals model, that exhibit identity to human AbetaP. Such antibodies are able to sequester peripheral AbetaP, thus avoiding passage through the blood brain barrier (BBB) and, as recently shown in a transgenic mouse model, to cross the BBB and dissolve already formed beta-amyloid plaques. To our knowledge, this is the first attempt to use as a vaccine a self-anti-aggregating epitope displayed on a phage, and this may pave the way to treat abnormal accumulation-peptide diseases, such as Alzheimer's disease or other amyloidogenic diseases.
Collapse
Affiliation(s)
- D Frenkel
- Department of Molecular Microbiology and Biotechnology, Faculty of Life Sciences, Tel-Aviv University, Ramat Aviv, Tel-Aviv 69978, Israel
| | | |
Collapse
|
120
|
Abstract
Alzheimer's disease (AD) is characterized by the progressive accumulation of amyloid fibrils composed of the amyloid beta-protein (A beta) in senile plaques. A beta is derived from the beta-amyloid precursor protein (APP) after beta- and gamma-secretase cleavages. beta-secretase was recently identified to be a membrane-anchored aspartyl protease that is widely distributed in subcellular compartments, including Golgi, trans-Golgi network, and endosomes. Although definitive identification of gamma-secretase will require reconstituting its activity in vitro, mounting evidence suggests that gamma-secretase is an unusual intramembrane-cleaving aspartyl protease. Two intramembranous aspartate residues in presenilin (PS) are absolutely required for A beta generation. Three classes of gamma-secretase inhibitors can directly bind to PS, strongly supporting the hypothesis of PSI as gamma-secretase. These results provide the molecular basis for therapeutic interventions that reduce A beta accumulation in AD patients by inhibiting beta- or gamma-secretase.
Collapse
Affiliation(s)
- W Xia
- Center for Neurologic Diseases, Brigham and Women's Hospital, 77 Avenue Louis Pasteur, HIM 616, Boston, MA 02115, USA.
| |
Collapse
|