WO2006067792A2 - Aldolase autoantigens useful in diagnosis and treatment of alzheimer's disease - Google Patents

Abstract

The present invention discloses the identification of an autoantigen useful in diagnosis and treatment of Alzheimer's disease. Specifically, the present invention relates to methods and kits for diagnosing Alzheimer's disease by determining the presence of anti-aldolase antibodies in a biological sample of a subject and to methods for treating Alzheimer's disease by modulating the immune response of the subject.

Description

ALDOLASE AUTO ANTIGENS USEFUL IN DIAGNOSIS AND TREATMENT

OF ALZHEIMER'S DISEASE

FIELD OF THE INVENTION The present invention relates to the diagnosis of Alzheimer's disease based on the determination of the presence of autoantibodies in a subject. Specifically, the present invention relates to methods and kits for diagnosing Alzheimer's disease by determining the presence of anti-aldolase antibodies in a biological sample of a subject and to methods for treating Alzheimer's disease by modulating the immune response to aldolase of the subject.

BACKGROUND OF THE INVENTION

Alzheimer's disease (AD), also referred to as Alzheimer type dementia, is the most common human neurodegenerative disease. The disease, first described by the Bavarian psychiatrist Alois Alzheimer in 1907, is characterized by progressive impairment in memory, behavior, language, and visual spatial skills, and ultimately, dementia. The course of the disease usually leads to death in a severely debilitated, immobile state between four and 12 years after onset. As life expectancy increases the incidence of AD and the health care expenditures for patients suffering from this incurable disease are increasing in Western societies. In the United States 1.9 to 4 million people have AD generating an annual cost estimated at 150 billion dollars (Clark and Karlawish 2003. Ann Intern Med 138:400-410). Alzheimer's disease is the fourth most common cause of death in the United States, next to heart disease, cancer and stroke. Characteristic pathologies of Alzheimer's disease include granulovascular neuronal degeneration, extracellular neuritic plaques with amyloid-β deposits, intracellular neurofibrillary tangles and neurofibrillary degeneration, synaptic loss, and extensive neuronal cell death.

Research on the causes of Alzheimer's disease has not been concluded in a single model which would satisfactory account for all the neuropathologic findings associated with the disease. The accepted paradigm on pathogenesis is that abnormally folded proteins (mainly amyloid-β and Tau) accumulate in the central nervous system (CNS) and lead to progressive neuronal loss, particularly in the cortex and hippocampus, (Nussbaum and Ellis 2003. N Engl J Med 348:1356-1364); this manifests clinically as deterioration in cognitive functions (Johnson 2000. J Anat 196:609-616).

In recent years, it has become evident that local inflammation is another important pathogenic mechanism operating in AD (Amaducci et al., 1992. Ann N Y Acad Sci 663:349-356; Chorsky et al., 2001. Med Hypotheses 56:124-127; Hulette and Walford, 1987. Alzheimer Dis Assoc Disord 1 :72-82; Weinerand and Selkoe, 2002. Nature 420:879-884) as well as in other neurodegenerative diseases such as Parkinson's disease (Weiner and Selkoe, supra) and prion disease (Betmouni, 1996. Neuroscience 74:1-5). Pathologically, immune system components were detected in the brains of patients suffering from Alzheimer's disease. These include antibodies, complement, and T cells (McGeer et al., 1994. Alzheimer Dis Assoc Disord 8:149-158). Recently, patients with AD were found to manifest T-cell reactivity to amyloid-β peptide (Monsonego et al., 2003 J Clin Invest 112:415-422), and antibodies to glial fibrillary acidic protein (GFAP) (Mecocci et al., 1995. J Neuroimmunol 57:165-170) and to other selected autoantigens (Ounanian et al., 1990. J Clin Lab Anal 4:367-375). Other studies have detected antibodies against uncharacterized antigen(s) in the choroid plexus (Serot et al., 1992. J Clin Pathol 45:781-783), microglial cells (Dahlstrom et al., 1994. MoI Neurobiol 9:41- 54) and antibodies against myelin basic protein (Singh et al., 1992. Neurosci Lett 147:25-28). In epidemiological studies, anti-inflammatory therapy was found to be linked to a lower incidence of AD (Etminan et al., 2003 BMJ 327:128). Moreover, recent work in animal models of AD have shown that the immune system can be recruited to clear amyloid deposits by active immunization to amyloid-β (Schenk et al., 1999. Nature 400:173-177) or by passive transfer of antibodies to amyloid-β (Weiner and Selkoe, supra).

When an individual is suspected of AD, several recommended tests are performed, including a psychometric test in the form of a Functional Assessment Questionnaire (FAQ) to examine the scale for functional autonomy; a set of laboratory tests including complete blood count, measurement of thyroid stimulating hormone, serum electrolytes, vitamin B 12 levels, serum calcium and serum glucose levels; and neuroimaging by computed tomography (CT) which has a role in detecting certain causes of dementia such as vascular dementia (VaD), tumor, normal pressure hydrocephalus or subdural hematoma. While Alzheimer's disease is the most common form of dementia, accounting for at least 60% of cases, diagnostic procedures for determining the exact cause of dementia, among more than 80 different species, is difficult at best.

The only true existing diagnosis of Alzheimer's disease is made by pathologic examination of postmortem brain tissue in conjunction with a clinical history of dementia. This diagnosis is based on the presence in brain tissue of neurofibrillary tangles and of neuritic (senile) plaques. However, this method cannot be used for an early stage diagnosis of patients suffering from Alzheimer's disease. While AD cannot be cured at present time, a symptomatic treatment is already available. The first drugs approved by the U.S. Food and Drug Administration are acetylcholinesterase inhibitors for the temporary improvement of cognition and behavior. In addition, various new drugs are now under investigation, as described herein below. Early detection and identification of Alzheimer's disease facilitate prompt, appropriate treatment and care. Thus, providing reliable and cost-effective methods for diagnosis of Alzheimer's disease would be highly beneficial.

U.S. Patent No. 6,811,988 discloses modified β-amyloid peptides, antibodies that specifically bind to the modified β-amyloid peptides, and methods for using these compositions in the diagnosis of Alzheimer's disease, as well as methods to monitor treatment and/or disease progression of Alzheimer's disease in patients. WO 99/27944 and related patents and patent applications disclose compositions and methods for treatment of amyloidogenic diseases, which entail administering an agent that induces a beneficial immune response against an amyloid deposit in the patient. The methods are particularly useful for prophylactic and therapeutic treatment of Alzheimer's disease. In such methods, a suitable agent is amyloid-β peptide or an antibody thereto.

U.S. Patent Application No. 20030152570 discloses a method for treating a condition related to the development of Alzheimer's disease (AD) which involves the removal of circulating autoantibodies of a biochemical marker or markers, specifically human glial fibrillary acidic protein (GFAP) and glyceraldehyde-3 -phosphate dehydrogenase (GAPDH), from the sera of a patient in an amount effective to reduce or eliminate phagocytosis of astrocytic cells. The invention further includes a process of immune system modulation effective for autoantibody removal. The lack of efficient treatment for Alzheimer's disease has prompted clinical trials of amyloid-β immunization in AD patients (Dodel et al., 2003. Lancet Neurol 2:215- 220; Monsonego and Weiner 2003. Science 302:834-838). However, the human study of amyloid- β vaccination was stopped prematurely as a fraction of the patients developed meningo-encephalitis, possibly as a result of autoimmunity induction (Dodel et al.; Mor et al., 2003. J Immunol 170:628-634; Weiner and Selkoe, supra). A recent study in mice reported autoimmune encephalomyelitis following immunization with amyloid-β peptide (Furlan et al., 2003. Brain 126:285-291).

Therefore, there is a recognized need for, and it would be highly advantageous to identify specific CNS antigens that can be used for immune intervention and thus treatment of Alzheimer's disease without risking autoimmune CNS attack.

SUMMARY OF THE INVENTION

The present invention provides means for the diagnosis of Alzheimer's disease (AD) based on the detection of aldolase antibodies in a biological sample of a subject, e.g. in a serum sample. The present invention further provides methods for the treatment of Alzheimer's disease by modulating the immune response of a patient suffering from

Alzheimer's disease.

The present invention is based in part on the finding that sera obtained from Alzheimer's disease patients were found to contain a specific antibody which reacts with brain and other tissue lysates. It is now disclosed for the first time that the target of the antibody is aldolase. The aldolase identified by the present invention is aldolase A, which is known to be present in the brain and to have high homology to aldolase C, which is also present in the brain. The novel findings of the present invention, disclosing aldolase as a common autoantigen in Alzheimer disease, provide new means for the diagnosis of AD as well as a new target of immune-modulation of this devastating incurable illness.

Thus, according to one aspect, the present invention provides a method for the diagnosis of Alzheimer's disease, the method comprising: a) providing a sample from a subject; b) contacting the sample with aldolase or an active fragment thereof, under conditions such that an immune reaction can occur to form an antigen- antibody complex; c) determining the presence of anti-aldolase antibodies in said sample; wherein the presence of anti-aldolase antibodies in said subject's sample is indicative of Alzheimer's disease.

According to one embodiment, step c may further comprise: i. contacting the aldolase-antibody complex with a detection antibody such that the detection antibody binds to said anti-aldolase-antibodies; and ii. detecting the binding of said detecting antibody to said anti-aldolase antibodies; wherein said binding of said detecting antibody to said anti-aldolase-antiboies is indicative of Alzheimer's disease.

According to certain embodiments, the aldolase is aldolase A. According to other embodiments, the aldolase is aldolase C. According to certain embodiments, the sample is selected from the group consisting of blood, plasma, serum, serous fluid, saliva, urine and cerebrospinal fluid (CSF).

According to preferred embodiments, the subject is a human subject. According to certain embodiments, the subject is selected from the group consisting of subjects displaying pathology resulting from Alzheimer's disease, subjects suspected of displaying pathology resulting from Alzheimer's disease, and subjects at risk of displaying pathology resulting from Alzheimer's disease.

According to another embodiment, the Alzheimer's disease diagnosed using the method of the present invention is selected from the group consisting of late onset Alzheimer's disease, early onset Alzheimer's disease, familial Alzheimer's disease and sporadic Alzheimer's disease.

According to further embodiments, the presence of anti-aldolase antibodies is determined by a method selected from the group consisting of, but not limited to, Western blots, enzyme-linked immunosorbent assays (ELISA), radioimmunoassays, and immunofluorescence assays. According to one embodiment, the method comprises an enzyme-linked immunosorbent assay. According to one embodiment, the enzyme-linked immunosorbent assay is selected from the group consisting of indirect enzyme-linked immunosorbent assays, indirect sandwich enzyme-linked immunosorbent assays, and competitive enzyme-linked immunosorbent assays. According to another embodiment, the enzyme-linked immunosorbent assay further comprises an alkaline phosphatase amplification system.

According to yet other embodiments, the detection antibody further comprises at least one conjugated enzyme selected from the group consisting of horseradish peroxidase, alkaline phosphatase, urease, glucoamylase and β -galactosidase.

According to another aspect, the present invention provides a kit for the diagnosis of Alzheimer's disease comprising an immobilized support, at least one aldolase or an active fragment thereof, and at least one detection antibody. According to preferred embodiments, the immobilized support is coated with the aldolase. According to another preferred embodiments, the aldolase is aldolase A. According to further preferred embodiments, the aldolase is aldolase C.

According to certain embodiments, the kit comprises an enzyme-linked immunosorbent assay kit. According to further embodiments, the kit comprises immobilized support precoated with aldolase, at least one coating buffer, at least one blocking buffer, distilled water, at least one antibody-enzyme conjugate directed against anti-aldolase antibodies, at least one enzyme-linked immunosorbent assay enzyme reaction substrate solution, and at least one amplifier system. According to preferred embodiments, the amplifier system is an alkaline phosphatase enzyme-linked immunosorbent assay amplifier system. According to another embodiments, the kit further comprises components selected from the group consisting of needles, sample collection tubes, microtiter plates, and instructions.

According to yet another aspect, the present invention provides a method of assessing efficacy of a treatment of Alzheimer's disease in a patient comprising: a) determining a baseline amount of anti-aldolase antibodies in a first sample obtained from the patient before receiving the treatment; b) determining the amount of the anti-aldolase antibodies in a second sample obtained from said patient after receiving said treatment; wherein a change in the amount of said anti-aldolase antibodies is correlated with a positive treatment outcome. According to one embodiment, the anti-aldolase antibodies are directed against aldolase A. According to another embodiment, the anti-aldolase antibodies are directed against aldolase C.

According to certain embodiments, the sample is selected from the group consisting of blood, plasma, serum, serous fluid, saliva, urine and cerebrospinal fluid. According to another embodiment, the amount of the anti-aldolase antibodies is determined in a sample obtained from a control population and in a sample obtained from a patient suffering from Alzheimer's disease and receiving a treatment, wherein a lack of significant difference between the amount of the anti-aldolase antibodies measured in a sample obtained after beginning of the treatment compared to the amount of said aldolase specific antibodies in a sample obtained from the control population indicates a positive treatment outcome.

The present invention disclosure that aldolase is an autoantigen involved in the pathogenesis of Alzheimer's disease provides new targets for modulating the immune system of an Alzheimer's patient. It has been demonstrated that Alzheimer's disease can be treated, at least to some extent, by employing various components of the immune system.

Thus, according to further aspect, the present invention provides a method for the treatment of Alzheimer's disease comprising modulating the immune response of an AD patient towards aldolase. Without intending to be bound by any hypothesis concerning mechanism of action, aldolase could represent one of several autoantigens participating in the perpetuation of autoimmune inflammation. The induction of tolerance to aldolase can down regulate such damaging inflammation. In addition, similar to the anti-amyloid-β peptide antibodies, certain types of anti-aldolase antibodies may be found to help clear senile plaques.

According to one embodiment, the present invention provides a method for inducing an immune response against at least one type of aldolase in a patient.

According to certain embodiments, the immune response is actively induced by administering an immunogen to an AD patient. According to one embodiment, the immunogen is aldolase or a peptide derived therefrom. According to certain embodiments, the treatment regime entails administering a dose of aldolase or a peptide derived therefrom to induce the immune response in the patient. According to one embodiment, aldolase or a fragment thereof is administered with an adjuvant that enhances the immune response to aldolase. According to preferred embodiments, the adjuvant is selected from the group consisting of pharmaceutically acceptable adjuvants approved for use in humans.

According to another embodiments, the immune response is induced by administering a therapeutically effective dose of a nucleic acid sequence encoding aldolase or an active fragment thereof. The nucleic acid encoding aldolase or fragment thereof is expressed in the patient to produce the aldolase or the active fragment in an amount that induces the immune response.

According to other embodiments, the immune response is passively induced by administering an antibody or an active fragment or derivative therefrom to an AD patient. According to one embodiment, the antibody is anti-aldolase antibody or an active fragment thereof. According to yet another embodiments, the immune response is passively induced by administering a nucleic acid sequence encoding an anti-aldolase antibody or an active fragment thereof, wherein the nucleic acid is expressed to produce anti-aldolase antibodies in an amount sufficient to induce the immune response.

Alternatively, the immune response is induced by removing T-cells from the patient, contacting the T-cells with aldolase or a peptide derived thereof under conditions in which the T-cells are primed, and re-introducing the T-cells in the patient.

The presence of anti-aldolase antibodies in the serum of AD patients can indicate that specific types of these antibodies could be a primary autoimmune factor in

Alzheimer's disease. Without wishing to be bound to any specific mechanism or theory, anti-aldolase antibodies could have pathogenic effects by inhibiting energy production and glucose use.

According to yet further embodiment, the present invention provides a method for the treatment of Alzheimer's disease comprising suppressing an immune response to aldolase in a patient.

According to certain embodiments, the immune response is suppressed by administering an anti anti-aldolase antibody peptide comprising at least part of an aldolase epitope. As used herein, the term "anti anti-aldolase antibody peptide" (AAAP) refers to a peptide, a peptide analog and a variant therefrom, providing the peptide comprises at least part of an aldolase epitope capable of eliciting an immune response in a subject. According to one embodiment, the AAAP is a soluble aldolase or an active fragment therefrom. According to another embodiment, the AAAP is an antibody against anti-aldolase antibody. According to yet another embodiment, the AAAP is a peptide capable of suppressing the synthesis of an anti-aldolase antibody.

The invention is explained in greater details in the description, figures, and claims that follow.

BRIEF DESCRIPTION OF THE FIGURES FIG. 1 shows the expression of the 42 kDa band in different tissues.

FIG. 2 shows a Western blot analysis of the 42 kDa band in human tissues. Rat brain lysate was used as a positive control for the 42 kDa band.

FIG. 3 describes a coverage map and error map of peptides detected by mass spectrometry. The 18 peptides comprised 39% of the rat aldolase A sequence. FIG. 4 shows sequence alignments of rat (gi 6978487), human (gi 34577112), and rabbit (gi 113608) aldolase A sequences.

FIG. 5 shows a Western blot of aldolase with serum obtained form AD patients. Aldolase A from rat brain, rat heart, and rabbit (1-16 μg) were run in parallel and tested in immuno-blot with Alzheimer's disease serum. FIG. 6 shows the results of ELISA assays of aldolase reactive IgG antibodies (panels A and B) and Glutamic-oxaloacetic transaminase (panela C and D). Each dot represents a single patient serum. 45 sera were tested for AD (A) and 23 from elderly controls (B). 28 AD and 19 elderly controls were tested with the control antigen (C and D). Elderly control patients were elderly patients without clinical evidence of dementia. FIG. 7 shows inhibition of aldolase activity by serum obtained from AD patients. FIG. 8 shows the effect of added substrate on the binding of anti-aldolase antibodies to aldolase.

FIG. 9 shows T-cell proliferation in the presence of increasing amounts of rabbit aldolase. FIG. 10 shows a Western blot analysis of rat tissue extracts probed with serum obtained from rats 25 days after immunization with Aldolase/CFA.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to methods for the diagnosis of Alzheimer's disease (AD), and to methods for the treatment of AD which are based on this diagnosis. In particular, the present invention provides methods for diagnosing Alzheimer's disease using antigen which specifically bind to antibodies indicative of Alzheimer's disease.

Specifically, the antigen is the glycolytic enzyme aldolase and the indicative antibodies are anti-aldolase antibodies. Based on the presence of such indicative antibodies in a sample obtained from a patient suffering from AD, the present invention further provides methods for the treatment of Alzheimer's disease comprising modulating the immune response of the patient towards the enzyme aldolase.

Definitions

The term "antibody" (or "antibodies") is used herein in the broadest sense and refers to intact molecules as well as fragments thereof, which binds specifically to an antigenic determinant, and specifically, binds to proteins identical or structurally related to the antigenic determinant which stimulated their production. Thus, antibodies are useful in assays to detect the antigen which stimulated their production. "Antibody fragments" comprise a portion of a full-length antibody, generally the antigen binding or variable region thereof. Examples of antibody fragments include Fab, Fab¹, F(ab')₂, and Fv fragments; diabodies; linear antibodies; single-chain antibody molecules; and multi-specific antibodies formed from antibody fragments.

Monoclonal antibodies are derived from a single clone of B lymphocytes (i.e., B cells), and are generally homogeneous in structure and antigen specificity. Polyclonal antibodies originate from many different clones of antibody-producing cells, and thus are heterogeneous in their structure and epitope specificity, but all recognize the same antigen. In some embodiments, monoclonal and polyclonal antibodies are used as crude preparations, while in preferred embodiments, these antibodies are purified. For example, in some embodiments, polyclonal antibodies contained in crude antiserum are used. Also, it is intended that the term "antibody" encompass any immunoglobulin (e.g., IgG, IgM, IgA, IgE, IgD, etc.) obtained from any source (e.g., humans, rodents, non- human primates, lagomorphs, caprines, bovines, equines, ovines, etc.).

As used herein, the terms "auto-antibody" or "auto-antibodies" refer to any immunoglobulin that binds specifically to an antigen that is native to the host organism that produced the antibody (i.e., the antibody is directed against "self antigens). The presence of autoantibodies is referred to herein as "autoimmunity."

As used herein, the term "antigen" is used in reference to any substance that is capable of being recognized by an antibody. It is intended that this term encompass any antigen and "immunogen" (i.e., a substance which induces the formation of antibodies). Thus, in an immunogenic reaction, antibodies are produced in response to the presence of an antigen or portion of an antigen. The terms "antigen" and "immunogen" are used to refer to an individual macromolecule or to a homogeneous or heterogeneous population of antigenic macromolecules. It is intended that the terms antigen and immunogen encompass protein molecules or portions of protein molecules, which contains one or more epitopes. The term "epitope" as used herein, refers to that fragment of a molecule that makes contact with a particular antibody. When a protein or fragment of a protein is used to immunize a host animal, numerous regions of the protein may induce the production of antibodies which bind specifically to a given region or three-dimensional structure on the protein; these regions or structures are referred to as "epitopes" or "antigenic determinants". An antigenic determinant may compete with the intact antigen (i.e., the immunogen used to elicit the immune response) for binding to an antibody.

As used herein, the terms "antigen fragment" and "portion of an antigen" and the like refer to a portion of an antigen. Antigen fragments or portions typically range in size, from a small percentage of the entire antigen to a large percentage, but not 100%, of the antigen. In some embodiments, antigen fragments and/or portions therefrom, comprise an "epitope" recognized by an antibody, and are therefore referred to as "immunoreactive fragments", while in other embodiments these fragments and/or portions do not comprise an epitope recognized by an antibody. In addition, in some embodiments, antigen fragments and/or portions are not immunogenic, while in other embodiments the antigen fragments and/or portions are immunogenic.

As used herein, the terms "peptide," "polypeptide" and "protein" all refer to a primary sequence of amino acids that are joined by covalent "peptide linkages." In general, a peptide consists of a few amino acids, typically from 2-50 amino acids, and is shorter than a protein. The term "polypeptide" encompasses peptides and proteins. In some embodiments, the peptide, polypeptide or protein is synthetic, while in other embodiments, the peptide, polypeptide or protein is recombinant or naturally occurring. A synthetic peptide is a peptide which is produced by artificial means in vitro (i.e., was not produced in vivo).

The term "sample" is used in its broadest sense and encompasses samples or specimens obtained from any source. As used herein, the term "sample" is used to refer to biological samples obtained from animals (including humans), and encompasses fluids, solids, tissues, and gases. In preferred embodiments of this invention, biological samples include cerebrospinal fluid (CSF), serous fluid, urine, saliva, blood, and blood products such as plasma, serum and the like. However, these examples are not to be construed as limiting the types of samples which find use with the present invention.

The term "aldolase" as used herein refers to an enzyme catalyzing the reaction of fructose 1,6 biphosphate to glyceraldehyde 3 phosphate and dihydroxyacetone phosphate. The term encompasses all types of aldolase, specifically aldolase A, aldolase

B and aldolase C. The enzyme is a tetramer of 40 KDa subunits, which appear in SDS gels as a 42 KDa band.

The term "immunological" or "immune" response as used herein is the development of a beneficial humoral (antibody mediated) and/or a cellular (mediated by antigen-specific T cells or their secretion products) response directed against aldolase in a recipient patient. Such a response can be an active response induced by administration of immunogen or a passive response induced by administration of antibody or primed

T-cells. A cellular immune response is elicited by the presentation of polypeptide epitopes in association with Class I or Class II major histocompatibility complex

(MHC) molecules to activate antigen-specific CD4⁺ T helper cells and/or CD8⁺ cytotoxic T cells. The response may also involve activation of monocytes, macrophages, NK cells, basophils, dendritic cells, astrocytes, microglia cells, eosinophils or other components of innate immunity. The presence of a cell-mediated immunological response can be determined by T cell proliferation assays. The relative contributions of humoral and cellular responses to the protective or therapeutic effect of an immnunogen can be distinguished by separately isolating IgG and T-cells from an immunized syngeneic animal and measuring protective or therapeutic effect in a second subject.

An "immunogenic agent" or "immnunogen" is capable of inducing an immunological response against itself on administration to a patient, optionally in conjunction with an adjuvant.

As used herein, the term "immunoassay" refers to any assay that uses at least one specific antibody for the detection or quantitation of an antigen. Immunoassays include, but are not limited to, Western blots, ELISAs, radioimmunoassays, and immunofluorescence assays. The terms "Western blot," "Western immunoblot" "immunoblot" and "Western" refer to the immunological analysis of protein(s), polypeptides or peptides that have been immobilized onto a membrane support. The proteins are first resolved by polyacrylamide gel electrophoresis (i.e., SDS-PAGE) to separate the proteins, followed by transfer of the protein from the gel to a solid support, such as nitrocellulose or a nylon membrane. The immobilized proteins are then exposed to an antibody having reactivity towards an antigen of interest. The binding of the antibody (i.e., the primary antibody) is detected by use of a secondary antibody which specifically binds the primary antibody. The secondary antibody is typically conjugated to an enzyme which permits visualization of the antigen-antibody complex by the production of a colored reaction product or catalyzes a luminescent enzymatic reaction.

As used herein, a "detection antibody" is an antibody which carries a means for visualization or quantitation, which is typically a conjugated enzyme moiety that typically yields a colored or fluorescent reaction product following the addition of a suitable substrate. Conjugated enzymes commonly used with detection antibodies in the ELISA include horseradish peroxidase, urease, alkaline phosphatase, glucoamylase and β-galactosidase. In certain preferred embodiments, the detection antibody is directed against the antibody of interest. Alternatively, the detection antibody is prepared with a label such as biotin, a fluorescent marker, or a radioisotope, and is detected and/or quantitated using this label.

The term "adjuvant" refers to a compound that when administered in conjunction with an antigen augments the immune response to the antigen, but when administered alone does not generate an immune response to the antigen. Adjuvants can augment an immune response by several mechanisms including lymphocyte recruitment, stimulation of B and/or T cells, stimulation of macrophages and stimulation of innate immunity (activation of Toll like receptors).

The term "patient" includes human subjects that are diagnosed to suffer from Alzheimer' s disease.

As used herein, the terms "Alzheimer's disease" and "AD" refer to a neurodegenerative disorder and encompass familial Alzheimer's disease and sporadic Alzheimer's disease. The term "familial Alzheimer's disease" refers to Alzheimer's disease associated with genetic factors (i.e., inheritance is demonstrated) while "sporadic Alzheimer's disease" refers to Alzheimer's disease that is not associated with prior family history of the disease. Symptoms indicative of Alzheimer's disease in human subjects typically include, but are not limited to, mild to severe dementia, progressive impairment of memory (ranging from mild forgetfulness to disorientation and severe memory loss), poor visual spatial skills, personality changes, poor impulse control, poor judgment, distrust of others, increased stubbornness, restlessness, poor planning ability, poor decision making, and social withdrawal. In severe cases, patients lose the ability to use language and communicate, and require assistance in personal hygiene, eating and dressing, and are eventually bedridden. Hallmark pathologies within brain tissue include extracellular neuritic β-amyloid plaques, neurofibrillary tangles, neurofibrillary degeneration, granulovascular neuronal degeneration, synaptic loss, and extensive neuronal cell death.

Autoantibodies in Alzheimer's Disease

Current concepts on the pathogenesis of Alzheimer's disease include the participation of the immune system (Weiner and Selkoe, supra). In contrast with the dominant role of the adaptive immune system in multiple sclerosis (MS), the major components considered to be operative in Alzheimer's disease belong to the innate immune system. Previous efforts to identify evidence for the involvement of the adaptive immune system in AD pathogenesis include search of autoantibodies found in other autoimmune diseases, as well as attempts to identify novel interactions with molecules known to be related to AD pathogenesis such as amyloid-β peptide or glial fibrillary acidic protein (GFAP). The present invention is based in part on an unbiased methodology in which serum samples obtained from Alzheimer's disease patients were screened for immunoglobulins indicative for the disease, i.e. immunoglobulins which are absent or appear at a lower concentration or frequency in serum samples obtained from healthy donors, and the further identification of the related antigen. These findings are partially described in a paper published by the inventors of the present invention after the priority date of the present invention (Mor et al, 2005. J of Immunol 175(5):3439-3445).

The present invention now discloses for the first time that anti-aldolase antibodies present in a sample of a subject are indicative for Alzheimer's disease. This finding provides tools for diagnosing Alzheimer's disease in a subject, preferably a human subject, and methods for treating the disease, which are based on these diagnostic tools.

Thus, according to one aspect, the present invention provides a method for the diagnosis of Alzheimer's disease, the method comprising: a) providing a sample from a subject; b) contacting the sample with aldolase or an active fragment thereof, under conditions such that an immune reaction can occur to form an antigen- antibody complex; c) determining the presence of anti-aldolase antibodies in said sample; wherein the presence of anti-aldolase antibodies in said subject's sample is indicative of Alzheimer's disease. According to one embodiment, determination of the presence of anti-aldolase antibodies in the sample may further comprise: i. contacting the aldolase-antibody complex with a detection antibody such that the detection antibody binds to said anti-aldolase-antibodies; and ii. detecting the binding of said detecting antibody to said anti-aldolase antibodies; wherein said binding of said detecting antibody to said anti-aldolase-antibodies is indicative of Alzheimer's disease.

According to certain embodiment, the aldolase is aldolase A. According to another embodiment, the aldolase is aldolase C. The diagnostic method of the present invention can be applied to subjects who have been previously diagnosed with Alzheimer's disease, those who are suspected of having Alzheimer's disease, and those at risk of developing Alzheimer's disease. For example, patients diagnosed with dementia, in particular, those patients who were previously clinically normal, are suitable subjects. However, it is not intended that the present invention be limited to use with any particular subject types.

The methods of the present invention are useful for detecting early onset Alzheimer's disease and late onset Alzheimer's disease, as well as for detecting sporadic Alzheimer's disease and familial Alzheimer's disease. As used herein, the term "early-onset Alzheimer's disease" refers to Alzheimer's disease cases diagnosed as occurring before the age of 65. As used herein, the term "late-onset Alzheimer's disease" refers to Alzheimer's disease cases diagnosed as occurring after the age of 65.

The diagnostic methods of the present invention are suitable for the detection and quantitation (i.e., measurement) of anti-aldolase antibodies in a sample, including, inter alia, the blood, serous fluid and CSF. Standard techniques known in the art are easily adapted to indicate and quantitate the levels of circulating anti-aldolase antibodies in such sample, including but not limited to, Western blots, ELISAs, radioimmunoassays, and immunofluorescence assays. Many different ELISA formats are known to those skilled in the art, indirect ELISA being specifically useful in the practice of the present invention. However, it is not intended that the present invention be limited to these assays. In additional embodiments, other antigen-antibody reactions are used in the present invention, including but not limited to "flocculation" (i.e., a colloidal suspension produced upon the formation of antigen-antibody complexes), "agglutination" (i.e., clumping of cells or other substances upon exposure to antibody), "particle agglutination" (i.e., clumping of particles coated with antigen in the presence of antibody), "complement fixation" (i.e., the use of complement in an antibody-antigen reaction method), and other methods commonly used in serology, immunology, immunocytochemistry, immunohistochemistry, and related fields. Factors contributing to the success of an ELISA method according to the present invention include their sensitivity, versatility, long reagent shelf life, ease of preparation of reagents, non-radioactive reagents, and assay speed. Furthermore, in some embodiments, the assay is quantitative. Reagents and equipment designed specifically for use in ELISA protocols are readily available from numerous manufacturers, including Bio-Rad, Dynatech Industries, GibcoBRL/Life Technologies, and more.

Many ELISA applications and formats have been described. Various sources provide discussion of ELISA chemistry, applications, and detailed protocols (See e.g., Crowther, "Enzyme-Linked Immunosorbent Assay (ELISA)," in Molecular Biomethods Handbook, Rapley et al. (eds.), pp. 595-617, Humana Press, Inc., Totowa, NJ., 1998; Ausubel et al. (eds.), Current Protocols in Molecular Biology, Ch. 11, John Wiley & Sons, Inc., New York, 1994).

In preferred embodiments of the present invention, indirect ELISA methods for quantitation of anti-aldolase antibody are provided. In certain embodiments, the antigen (i.e., aldolase or an immunoreactive part therefrom) is first immobilized on a solid support (e.g. by coating a microtiter plate well). A test sample (e.g., a serum sample) is then added to the antigen-coated support. If the test sample contains anti-aldolase antibodies, these antibodies specifically bind to the purified antigen coating the support. The aldolase-reactive antibodies are then visualized by the addition of a second detection antibody, where the detection antibody is species-specific or isotype-specific for anti-aldolase antibody and is coupled to an enzyme. As indicated previously, enzymes commonly used in ELISAs include horseradish peroxidase (HRPO), urease, alkaline phosphatase, glucoamylase and β-galactosidase. Protocols for the preparation of suitable antibody-enzyme conjugates are well known in the art. Such conjugate are also available commercially.

The end product of an ELISA is a signal typically observed as the development of color or fluorescence. Typically, this signal is read (i.e., quantitated) using a suitable spectrocolorimeter (i.e., a spectrophotometer) or spectrofluorometer. The amount of color or fluorescence is directly proportional to the amount of the anti-aldolase antibodies present in the sample. To obtain a quantitative measurement, the sample suspected to contain anti-aldolase antibodies is applied in several dilutions to obtain a concentration-dependent signal. According to certain embodiments, the diagnostic method of the present invention is particularly useful for monitoring a course of treatment being administered to a patient. The methods can be used to monitor both therapeutic treatment on symptomatic patients and prophylactic treatment on asymptomatic patients. When assessing the efficiency of treating AD by the administration of an agent, the diagnostic method of the present invention requires determining a baseline concentration of anti-aldolase antibodies in a sample obtained from a patient before administering a dosage of the agent. The baseline value is then compared with a value of anti-aldolase antibodies after the treatment. A significant change (i.e., greater than the typical margin of experimental error in repeat measurements of the same sample, expressed as one standard deviation from the mean of such measurements) in the concentration of the anti-aldolase antibodies indicates a positive treatment outcome. In general, patients undergoing an initial course of treatment with an agent are expected to show an increase in the response with successive dosages, which eventually reaches a plateau. Administration of agent is generally continued while the response is increasing. Attainment of the plateau is an indicator that the administered treatment can be discontinued or reduced in dosage or frequency.

In certain embodiments, a control value (i.e., a mean and standard deviation) of anti-aldolase antibody concentration is determined for a control population. A lack of significant difference in the antibody concentration in a sample obtained from an AD patient relative to the value obtained in the control population indicates a positive treatment outcome.

The present invention also provides kits for the detection of anti-aldolase antibodies. According to one currently preferred embodiment, the kit is ELISA kit. In addition, in certain embodiments, the kits are customized for various applications. However, it is not intended that the kits of the present invention be limited to any particular format or design. According to certain embodiments, the kits of the present invention include, but are not limited to, materials for sample collection (e.g., spinal and/or vein puncture needles), tubes (e.g., sample collection tubes and reagent tubes), holders, trays, racks, dishes, plates (e.g., 96-well microtiter plates), instructions to the kit user, solutions or other chemical reagents, and samples to be used for standardization, and/or normalization, as well as positive and negative controls. In particularly preferred embodiments, reagents included in ELISA kits specifically intended for the detection of anti aldolase antibodies include aldolase or an immunoreactive peptide derived therefrom, control anti aldolase antibody, anti aldolase antibody-enzyme conjugate, microtiter plates or other immobilized supp precoated with aldolase, buffers (e.g., coating buffer, blocking buffer, and distilled water), enzyme reaction substrate and premixed enzyme substrate solutions.

Aldolase is a glycolytic enzyme catalyzing the reaction converting fructose 1,6 biphosphate to glyceraldehyde 3 phosphate and dihydroxyacetone phosphate. Aldolase is conserved in evolution and exist in three types: type A is the major form found in muscles; type B in liver and kidney; and type C in brain together with type A.

Without wishing to be bound to a specific theory or mechanism, the presence of aldolase-specific antibodies in a serum obtained from Alzheimer's disease patients may contribute to the disease pathology via several routes. The presence of the aldolase antibodies in the serum of an Alzheimer's disease patient can result from inflammatory reactions associated with the disease, which lead to cell damage and thus enhance the permeability of the blood-brain barrier. As a result, cell contents including aldolase are released to the periphery, priming the immune system. Aldolase or certain fragments thereof could represent one of several autoantigens that cause autoimmune inflammation. In this case anti-aldolase antibodies could be a primary autoimmune factor in Alzheimer's diseaseand the induction of tolerance to aldolase might help down-regulate the damaging inflammation.

Alternatively, similar to the natural anti β-amyloid peptide antibodies (Hyman B. T. et al., 2001. Ann Neurol 49:808-810), anti-aldolase antibodies could represent a beneficial, protective immune reaction. In this context, reduced cellular metabolism offers survival advantage to neurons, in analogy to the mechanism suggested regarding the protection of brain cells from hypoxia (Bickler P. E. et al., 2002. Neuroscientist 8:234-242) and similar to the protective effect offered by inhibition of glyceraldehydes- 3-phosphate dehydrogenase on brain cells (Kragten E. et al., 1998. J Biol Chem 273:5821-5828; Tatton W. G. et al., 2000. J Neural Transm Suppl 60:77-100). Anti- aldolase antibodies may also be found to clear senile plaques as was found for anti β- amyloid antibodies.

Based on the phenomenon disclosed by the present invention of elevated concentrations of anti-aldolase antibodies in a sample of Alzheimer's disease patients, the present invention further discloses methods for the treatment of Alzheimer's disease comprising modulating the immune response of a patient towards aldolase.

According to certain embodiments, the present invention provides methods for treating Alzheimer's disease, which methods induce an immune response against aldolase. Inductions of the immune response can be achieved by administering the aldolase protein itself, variants therefrom, analogs and mimetics of aldolase that induce and/or cross-react with antibodies to aldolase, and antibodies or T-cells reactive with aldolase. The induction of an immune response can be active, as when an immunogen is administered to induce antibodies or T-cells reactive with aldolase in a patient, or passive, as when an antibody is administered that itself binds to aldolase in a patient. As is shown in Example 6 herein below, Lewis rats, NOD and C57B1 mice immunized against aldolase A did not develop signs of autoimmune disease, indicating that aldolase can be safely used for inducing the immune response. According to certain embodiments, induction of the immune response is achieved by administering an active fragment or an analog of a natural aldolase that contains an epitope that induces a similar immune response as compared to the natural polypeptide. Immunogenic fragments typically have a sequence of at least 3, 5, 6, 10 or 20 contiguous amino acids from a natural peptide. Analogs include allelic, species and induced variants. Analogs typically differ from the naturally occurring polypeptides at one or a few positions, often by virtue of conservative substitutions, and typically exhibit at least 80% or 90% sequence identity with natural polypeptides. Some analogs also include unnatural amino acids or modifications of N or C terminal amino acids. Examples of unnatural amino acids are α-α-disubstituted amino acids, N-alkyl amino acids, lactic acid, 4-hydroxyproline, γ-carboxyglutamate, O-phosphoserine, N- acetylserine, N-formylmethionine, 3-methylhistidine, and 5-hydroxylysine.

Aldolase, its fragments, analogs and fragment comprising an active epitope can be synthesized by solid phase peptide synthesis, produced by recombinant expression system, or can be obtained from natural sources. Automatic peptide synthesizers are commercially available from numerous suppliers, for example Applied Biosystems, Foster City, Calif. Recombinant expression can be in bacteria, such as E. coli, yeast, insect cells or mammalian cells. Procedures for recombinant expression are described by Sambrook et al, Molecular Cloning: A Laboratory Manual (C.S.H.P. Press, NY 2d ed., 1989). Some forms of aldolase are also available commercially (for example rabbit muscle aldolase, Sigma).

Alternatively, an immunogenic polypeptide, such as aldolase or immunogenic fragment therefrom can be presented as a viral or bacterial vaccine. A nucleic acid encoding the immunogenic polypeptide is incorporated into a genome or episome of the virus or bacteria. Optionally, the nucleic acid is incorporated in such a manner that the immunogenic peptide is expressed as a secreted protein or as a fusion protein with an outer surface protein of a virus or a transmembrane protein of a bacterium so that the peptide is displayed. Viruses or bacteria used in such methods should be nonpathogenic or attenuated. Suitable viruses include adenovirus, HSV, vaccinia and fowl pox. Fusion of an immunogenic peptide to HBsAg of HBV is particularly suitable. Therapeutic agents also include peptides and other compounds that do not necessarily have a significant amino acid sequence similarity with aldolase but nevertheless serve as mimetics of aldolase and induce a similar immune response. Anti-idiotypic antibodies against monoclonal antibodies to aldolase can also be used. Such anti-idiotypic antibodies mimic the antigen and generate an immune response to it (see Essential Immunology (Roit ed., Blackwell Scientific Publications, Palo Alto, 6th ed., p. 181).

Therapeutic agents that induce an immune response against aldolase to be used with the methods of the present invention also include antibodies that specifically bind to aldolase or an immunogenic fragment therefrom. Such antibodies can be monoclonal or polyclonal. The production of non-human monoclonal antibodies, e.g., murine or rat, can be accomplished by, for example, immunizing the animal with aldolase (see, for example, Harlow E. and Lane D. (eds.) 1988. Antibodies, A Laboratory Manual CSHP NY). Such an immunogen can be obtained from a natural source, by peptides synthesis or by recombinant expression.

Humanized forms of mouse antibodies can be generated by linking the CDR regions of non-human antibodies to human constant regions by recombinant DNA techniques (see, for example, Queen et al., 1989. Proc. Natl. Acad. Sci. USA 86:10029- 10033, 1989 and WO 90/07861).

Human antibodies can be obtained using phage-display methods. In these methods, libraries of phage are produced in which members display different antibodies on their outer surfaces. Antibodies are usually displayed as Fv or Fab fragments. Phage displaying antibodies with a desired specificity are selected by affinity enrichment to aldolase or fragments therefrom. Human antibodies against aldolase can also be produced from non-human transgenic mammals having transgenes encoding at least a segment of the human immunoglobulin locus and an inactivated endogenous immunoglobulin locus. Human antibodies can be selected by competitive binding experiments, or otherwise, to have the same epitope specificity as a particular mouse antibody. Such antibodies are particularly likely to share the useful functional properties of the mouse antibodies. Human polyclonal antibodies can also be provided in the form of serum from humans immunized with an immunogenic agent. Optionally, such polyclonal antibodies can be concentrated by affinity purification using aldolase as an affinity reagent.

Human or humanized antibodies can be designed to have IgG, IgD, IgA and IgE constant region, and any isotype, including IgGl, IgG2, IgG3 and IgG4. Antibodies can be expressed as tetramers containing two light and two heavy chains, as separate heavy chains, light chains, as Fab, Fab' F(ab')₂, and Fv₅ or as single chain antibodies in which heavy and light chain variable domains are linked through a spacer.

Therapeutic immunogenic agents for use in the present methods also include allogeneic autologous T-cells that bind to aldolase. Methods for T-cell activation are known to those skilled in the art, and include for example the methods described in Aciron et al. (Achiron et al., 2004. Clinical Immunol. 113:155-160). Alternatively, T- cells can be activated against aldolase by expressing a human MHC class I gene and a human β-2-microglobulin gene from an insect cell line, whereby an empty complex is formed on the surface of the cells and can bind to aldolase. T-cells contacted with the cell line become specifically activated against aldolase (See U.S. Patent No. 5,314,813). Insect cell lines expressing an MHC class II antigen can similarly be used to activate CD⁴ T cells.

Some agents for inducing an immune response contain the appropriate epitope for inducing an immune response against aldolase but are too small to be immunogenic. In this situation, a peptide immunogen can be linked to a suitable carrier to help elicit an immune response. Suitable carriers include serum albumins, keyhole limpet hemocyanin, immunoglobulin molecules, thyroglobulin, ovalbumin, tetanus toxoid, or a toxoid from other pathogenic bacteria, such as diphtheria, E. coli, cholera, or H. pylori, or an attenuated toxin derivative. Other carriers for stimulating or enhancing an immune response include cytokines such as IL-I, IL- lα and β peptides, IL-2, γINF, IL-IO, Granulocyte-macrophage colony-stimulating factor (GM-CSF), and chemokines, including but not limited to MlPlα, MlPl β and RANTES (MCP2).

Immune responses against aldolase can also be induced by administration of nucleic acids encoding aldolase, an immunogenic fragment therefrom or other immunogenic peptides. Such nucleic acids can be DNA or RNA. A nucleic acid segment encoding the immunogen is typically linked to regulatory elements, such as a promoter and enhancer, that allow expression of the DNA segment in the intended target cells of a patient. For example promoter and enhancer elements from light or heavy chain immunoglobulin genes or the CMV major intermediate early promoter and enhancer are suitable to direct expression in blood cells. The linked regulatory elements and coding sequences are often cloned into a vector. Alternatively, the methods provided by the present invention for the treatment of

Alzheimer's disease are targeted at the suppression of the immune response. As described herein above, the presence of an antibody specific for an endogenous antigen, specifically the presence of anti-aldolase antibody may indicate a deleterious autoimmune processes leading to the observed pathologies of Alzheimer's disease. Without wishing to be bound to a specific mechanism, the anti-aldolase antibodies may enter brain cells, bind the enzyme and hinder its function, liking the presence of antibodies to reduced glucose utilization.

According to certain embodiments, the present invention provides a method for the treatment of Alzheimer's disease comprising suppressing an immune response to aldolase in a patient.

Suppression of the immune response of a subject to specific antigen may be attained via various routes.

One route employs a direct hindrance of the antibody activity, such that its antigen-binding efficacy is reduced or completely abolished. This may be achieved by the administration of antibodies against the anti-antigen antibody (anti-aldolase antibody according to the present invention). Such antibodies may be produced by any suitable method as is known to a person skilled in the art. In addition, any compound capable of interfering with the binding of anti-aldolase antibody to aldolase can serve as a suppressor according to the present invention.

Alternatively, soluble antigen or immunogenic fragment therefrom which compete with the natural autoantigen and thus reduce the undesirable reactivity of the antibody can be administered. However, in taking this approach one should be aware that antigen administration may lead to the stimulation of the immune response and thus to exacerbation rather than improvement of the antibody-mediated disease symptoms.

Administration of specific fragment of aldolase may be therefore preferable. Such antigen fragments may decrease the presence of free anti-aldolase antibodies by direct interactions. Administration of specific antigen fragment can suppress the immune response also via the suppression of antibody production as described for example, in

U.S. Patent No. 6,759,385.

Suppression of a specific immune response can be also achieved via oral administration of an antigen. Oral tolerance describes the observation that repetitive oral administration of an antigen reduced or inhibited the immune response specific for the particular antigen administered. Recently, the antigen-specific tolerance induction has been utilized as a treatment for various autoimmune diseases. For example, the repetitive oral administration of type II collagen (CII) or basic protein (MBP) has been reported to be effective for the treatment of collagen-induced arthritis (CIA) or experimental allergic encephalomyelitis (EAE), respectively.

According to the present invention, Alzheimer's disease can be monitored and treated by repetitive oral administration of aldolase to patients and the following measurements of the anti-aldolase antibody titer. Reduction in the anti-aldolase antibody titer is correlated with a positive treatment outcome; this may be also examined for correlation with cognitive functions, wherein lack of deterioration or an improvement in the cognitive function is considered as a positive outcome. Several factors may affect the effectiveness of tolerance induction, including suitable formulation of the antigen for oral intake and further absorbance, as described, for example, in WO 01/12222.

Direct removal of circulating auto-anti-aldolase antibodies from the serum of an Alzheimer's patient may be also employed, as described for example in U.S. Patent Application No. 20030152570 for the removal of autoantibodies against human glial fibrillary acidic protein (GFAP) and glyceraldehyde-3 -phosphate dehydrogenase (GAPDH). Specifically, passing the serum of an Alzheimer's disease patient through affinity columns containing aldolase can lower anti-aldolase antibody levels in the patient's serum.

As described herein above, one problem in treating patients suffering from Alzheimer's disease is the inaccuracy or delay in the disease diagnosis, resulting in a sub-optimal treatment regime. The present invention advantageously discloses methods for the diagnosis of Alzheimer's disease and methods for treatment based on the diagnosis outcome. Accordingly, patients amenable to treatment according to the methods of the present invention are those diagnosed to have in their serum anti- aldolase antibodies.

Effective treatment regime depends upon many different factors, including means of administration, target site, physiological state of the patient, and other medications administered. Treatment dosages need to be titrated according to the desired outcome (induction or suppression of the immune response) to optimize safety and efficacy. When an immunogen is administered, its amount depends on whether adjuvant is also administered, with higher dosages being required in the absence of adjuvant. The timing of treatment employment can vary significantly according to the amount of anti-aldolase antibodies present in a patient's sample after the treatment.

Agents for modulating an immune response can be administered by parenteral, topical, intravenous, oral, subcutaneous, intraperitoneal, intranasal or intramuscular means for prophylactic and/or therapeutic treatment. The most typical route of administration is subcutaneous although others can be equally effective. The next most common is intramuscular injection. This type of injection is most typically performed in the arm or leg muscles. Intravenous injections as well as intraperitoneal injections, intraarterial, intracranial, or intradermal injections are also effective in modulating an immune response.

Agents for modulating the immune response against aldolase according to the methods of the present invention can optionally be administered in combination with other agents that are at least partly effective in treatment of Alzheimer's disease.

Additional advantage of the methods of treatment of the present invention is that the administered agents are targeted at the immune system of the patient, and thus do not have to cross the blood-brain barrier, as other agents for the treatment of Alzheimer's disease which should be targeted to the damaged area of the brain.

Immunogenic agents of the invention, such as peptides or small polypeptides, are sometimes administered in combination with an adjuvant. A variety of adjuvant types can be used in combination with a peptide, such as aldolase, to elicit an immune response. Preferred adjuvant types augment the intrinsic response to an immunogen without causing conformational changes in the immunogen that affect the qualitative form of the response. Preferred adjuvants include alum, 3 De-O-acylated monophosphoryl lipid A (MPL), QS21, a triterpene glycoside or saponin isolated from the bark of the Quillaja Saponaria Molina tree found in South America (see U.S. Patent No. 5,057,540). Other adjuvants are oil in water emulsions (such as squalene or peanut oil), optionally in combination with immune stimulants, such as monophosphoryl lipid A. Another adjuvant is CpG (Bioworld Today, Nov. 15, 1998). Alternatively, aldolase or a fragment thereof can be coupled to an adjuvant. For example, a lipopeptide version of aldolase can be prepared by coupling palmitic acid or other lipids directly to the N- terminus of aldolase as described for hepatitis B antigen vaccination. However, such coupling should not substantially change the conformation of aldolase so as to affect the nature of the immune response thereto. Adjuvants can be administered as a component of a therapeutic composition with the active, immunogenic agent, or can be administered separately, before, concurrently with, or after administration of the immunogenic agent. The adjuvant can be administered as a component of a therapeutic composition with an active agent or can be administered separately, before, concurrently with, or after administration of the therapeutic agent.

EXAMPLES Materials and methods

Patient selection: Forty-five patients with Alzheimer's disease were randomly selected from the patients admitted to Internal Medicine A, Rabin Medical Center, Hasharon Hospital, Israel. All patients had dementia and were previously diagnosed as suffering from Alzheimer's disease. Patients with multiple cerebro-vascular accidents or

Parkinson's disease were excluded. Control sera were obtained from elderly patients with preserved cognitive functions, from healthy blood donors and from patients with multiple sclerosis (MS). Sera were obtained after informed consent from patients or from legal guardians.

Tissue isolation. Samples of tissues were homogenized using 1% Nonidet P-40 in 0.9% NaCl, 50 niM Tris, 1 mM EDTA, containing protease inhibitors (Sigma, Rehovot, Israel). Brain, heart, liver, thymus, spinal cord, intestine and fat tissue were homogenized with a tissue homogenizer in this buffer.

Antigens: Rabbit muscle aldolase and glutamic-oxaloacetic transaminase type I from porcine heart were purchased from Sigma (Rehovot, Israel). Purified human glial fibrillary acidic protein was purchased from Biodesign International. Complete

Freund's adjuvant was prepared with incomplete Freund's adjuvant into which 4 mg/ml

Mycobacterium tuberculosis H37Ra (Difco, Detroit, MI) was added.

Western blotting: Cell suspensions of thymocytes or tissue homogenates were lyzed in lysis buffer. The protein concentration was determined using the Bio-Rad Dc protein assay, based on the Lowry method (Bio-Rad laboratories, Hercules, CA). From cell and tissue lysates, 50 μg of protein were loaded in each well. After electrophoresis in 12% SDS gel in a mini-gel apparatus (Bio-Rad), the gels were electro-transferred to nitrocellulose membranes (Schleicher and Schuell, Dassel, Germany).

The nitrocellulose membranes were washed with distilled water for 5 min, and then blocked for 60 min. using a blocking solution composed of 2% milk powder (blotting grade blocker, non-fat dry milk, Bio-Rad), in PBS. After 3 X 10 min washes in PBS/0.05% Tween 20 (Sigma), patient sera (diluted 1/1000) were incubated with the membranes in blocking solution for 60 min. Following another series of washes in PBS/0.05% Tween 20 (3 X 10 min), the membranes were incubated with a secondary antibody (Peroxidase conjugated goat anti-human IgG H+L; Jackson Immuno-Research, West Grove, PA.) at a 1/2500 dilution in blocking solution for 60 min. After another 3 X lO min washes, the membranes were incubated with the ECL reagent (for 2 min) and exposed to X-ray film for 15-90 seconds. For size determination, pre-stained broad range protein standard markers were used (Fermentas Inc, Hanover, MD). Q Sepharose Ion exchange chromatography: A brain lysate was obtained from

Lewis rats. A free-flow column was packed to a volume calculated as a ratio of 10 mg protein per 1 ml of Q Sepharose free-flow beads (Pharmacia LKB, Sweden). After equilibration of the column with 3 volumes of 20 mM Tris-HCl, the lysate was loaded and the flow-through fraction collected. The proteins bound to the Q Sepharose column were eluted with increasing concentrations of NaCl (0.1-2.0 M). The different fractions were run on SDS-PAGE, and the protein bands were examined in Western-blots. The 42-kDa band was found in the flow through fraction. The enriched fraction was lyophilized run in gel and subjected to enzymatic digestion and mass spectrometry.

In Gel digestion and Mass-Spectrometry: The identified band was excised from the gel and subjected to trypsin digestion, and peptide fragments were analyzed by the Mass Spectrometry unit of the Weizmann Institute, Rehovot, Isreal, using Matrix- assisted laser desorption/ionization (MALDI) mass spectrometer. Analysis was performed with Bruker REFLEX™ reflector time-of-flight instrument with SCOUT™ multiprobe (384) inlet and grindless delayed extraction ion source. The protein was identified using ProFound program (version 4.10.5, The Rockefeller University Edition). Enzyme inhibition assay: Aldolase activity was measured after incubation of the enzyme with fructose 1 ,6-diphosphate and hydrazine (Sigma) (Jagannathan, V., et al., 1956. Biochem J 63:94-105). The test serum was first incubated with enzyme for 1 h at 37⁰C, and then the mixture was added to the hydrazine solution. The substrate, at concentrations from 16μM to 12 mM, was added immediately before the start of readings. The product was measured by the change in absorbance at 240 nm in a Power Wave micro plate spectrophotometer (Bio-Tek Instruments). Change in absorbance was measured every 6 seconds for several minutes in microtiter wells. Control assays were performed without serum or with control serum.

Animals: Inbred female Lewis rats and mice were supplied from the Weizmann Institute animal breeding center and were used at 2-3 months of age.

Animal immunization: Group of eight female Lewis rats was immunized in both hind footpads with 50 μg of rabbit muscle aldolase (Sigma) in complete Freund's adjuvant (CFA). CFA was composed of incomplete Freund's adjuvant (Difco, Detroit, MI) supplemented with 4 mg/ml of mycobacterium tuberculosis H37Ra (Difco). The rats were observed for signs of disease from day 10 post-immunization. Twenty-five days after immunization, the rats were sacrificed and their tissues were prepared for histological examination. The tissues (heart, muscle, liver, cerebrum, cerebellum and spinal cord) were embedded in paraffin, and sections were stained with hematoxylin and eosin. Groups of six female NOD and six female C57BL mice were injected sub cutaneously with aldolase in CFA (50 μg/mouse). On the day of immunization and after 48 h, the mice received 200 ng of pertussis toxin intraparenteraly. The immunized mice were cored for clinical signs for three weeks, and then they were scarified and tissue were analyzed for histochemical lesions.

T Cell proliferation assay: T-cell proliferation assay was performed by seeding 5x10⁴ line cells (at the 4^th day in propagation phase) with 5x10⁵ irradiated (2500R) thymocytes as antigen presenting cells, in stimulation medium for 3 days, in 96 micro- titter round bottom wells (Nunc, Rosklide, Denmark). Stimulation medium was composed of DMEM supplemented with 2 mercaptoethanol (5x10"⁵ M), L-glutamine (2 mM), sodium pyruvate (1 mM), penicillin (100 u/ml), streptomycin (100 μg/ml), nonessential amino acids (1 ml/100 ml, Bio Lab Jerusalem, Israel), and autologous serum 1% (v/v) (Mor, F., and Cohen, I. R., 1993. J Clin Invest 92:2199-2206). The cultures were incubated in quadruplicate for 72 hours at 37°C in humidified air containing 7% CO2. Each well was pulsed with 1 μCi of [³H] thymidine (10 ci/mmol specific activity, Amersham, Buckinghamshire, England) for the final 4 hours. The cultures were then harvested using a MicroMate 196 Cell Harvester and cpm was determined using a Matrix 96 Direct Beta Counter using avalanche gas (98.7% helium; 1.3% C4H10) ionization detectors (Packard Instrument Company, Meriden, CT, USA). The results of proliferation are expressed as cpm.

Aldolase T cell line: Popliteal lymph node cells from rats immunized 25 days previously with aldolase in CFA were stimulated in vitro with aldolase (10 μg/ml) in stimulation medium, as described (Mor, F., and Cohen, I. R., 1995. J Immunol 155:3693-3699.). The T-cell line was expanded by stimulation every 10-12 days with antigen and irradiated thymocytes as antigen presenting cells (Mor and Cohen 1993, supra). Lewis rats were injected with 2x10⁷ T cell line blasts, and were clinically scored for two weeks after inoculation. Tissues were examined by histology 10 days after inoculation. ELISA to aldolase: ELISA microtiter plates (Maxisorp, Nunc) were coated with antigen (rabbit muscle aldolase or as a control enzyme of a similar molecular size, 10 μg/ml pig heart glutamic-oxaloacetic transaminase, in 0.1 M carbonate buffer) for 1 hr in 37⁰C. Next, blocking was done with 2% low fat milk powder (Bio-Rad) for 1 hr at 37°C. After washing with PBS/Tween, sera were diluted 1/70 in 2% milk and incubated for 1 hr at 37⁰C. Following 3 washes (0.05% Tween-20 in PBS), a secondary antibody (anti human IgG coupled to alkaline phosphatase, diluted 1/2000 in 2% milk) was added for 1 hr at 37°C. In the next step, the microtiter plate wells were washed with PBS/Tween, and incubated with alkaline phosphatase substrate tablet (Sigma) in diethanolamine buffer for 20-30 min. Color (OD) was read with ELISA reader at 405 nm. Sera were considered positive if the OD value exceeded the mean +2SD of control sera: mean ± SD; OD of control sera was 0.26 ± 0.075. An OD >0.41 indicated a positive result.

ELISA with addition of fructose 1,6-diphosphate: To test the effect of enzyme substrate on the binding of antibodies to aldolase, test wells were coated with aldolase in fructose 1,6-diphosphate (12 mM) in 0.1 M Tris, pH 7.3, or in 0.1 M Tris without fructose. Blocking, sera dilution, and secondary antibodies were done in 2% milk (Bio- Rad) as above. Sera from Alzheimer's disease patients were diluted 1/50 and 1/250.

Example 1: Detection of compound(s) reactive with serum of AD patients

Lysates of rat tissues were run in polyacrylamide gel electrophoresis (PAGE), followed by transfer to nitrocellulose paper. To identify IgG antibodies to tissue components, the serum of a typical patient with Alzheimer's disease was analyzed. The serum was tested in immunoblot against a panel of rat tissues. Figure 1 shows a positive reaction of the serum to a 42 kDa band in extracts of brain, heart, thymus, spinal cord and fat. No reactivity with this band was observed with lysates of liver and intestine.

Forty-four additional sera from patients with Alzheimer's disease were tested in immunoblot against brain and heart lysates (Table 1). Twenty-two additional patients were found to be strongly positive for reactivity to the 42 kDa band. A similar analysis of 20 healthy blood donors and 25 elderly patients without dementia were negative for antibodies to the 42 kDa band in Western blots (not shown). No correlation between the presence of the 42 kDa band and specific clinical manifestation of Alzheimer's disease was found. Table 1 : Clinical information regarding the Alzheimer's disease patients

# Age Sex Clinical Information Aldolase reactivity

1 75 F Fall Head trauma COPD 0.4810

2 76 F Pneumonia Respirator 0.2920

3 86 F Urinary infection 0.1910

4 83 F URI 0.1460

5 79 F Pseudomem Colitis 0.2930

6 97 F Bilat Pneumonia respirator 0.5190

7 92 F Pneumonia 2.5820

8 83 F Pneumonia, old TB 1.7140

9 98 F Fever 0.4010

10 84 F AIz Gastrostom CD colitis 0.3430

11 84 F ARF 1.3060

12 90 F TIA 1.3270

13 71 F Mild dementia 0.1550

14 95 M #hip CRF 0.2730

15 96 F FUO 1.6040

16 89 F Pneumonia 0.2390

17 80 M Dementia 0.3800

18 77 F CVA 0.2740

19 87 M Hyponatremia 0.2650

20 90 F Fever 0.3500

21 88 F Dementia 0.4270

22 83 M Dementia 0.4740

23 79 F Dementia 2.2320

24 78 F Dementia 0.2070

25 80 F Pulmonary edema 0.2340

26 83 F General deterioration 1.1780

27 92 F Bronchitis 2.6880

28 88 F Dementia 1.5320

29 84 F Pneumonia 0.2140

30 94 F Dementia 0.3790

31 77 M Dementia mild 0.9160

32 81 M Dementia 0.7360

33 94 M Syncope, dementia 0.3260

34 81 F suspected NPH Dementia not certain 0.1900

35 78 F Dementia mild 0.4410

36 85 M Severe Dementia 0.3100

37 80 M Dementia 0.2140

38 78 F Anemia Diverticulosis 0.5190

39 95 F Urosepsis Dementia mild 0.2140

40 75 F Dementia mild, Hypercalcemia 0.1740

41 81 F Severe Dementia 0.2110

42 83 M Dementia Osteomyelitis 0.1780

43 88 M Dementia, Chest pain 0.1600

44 87 F Pneumonia, Dementia 0.2550

45 78 M Dementia 2.1210 The detection of aldolase antibodies in 50% of patients can have several explanations. First, the clinical diagnosis of AD is not definite and is given after ruling out other diseases characterized by dementia. A definite diagnosis can only be made at autopsy (Nussbaum and Ellis, supra). Thus, in some of the anti-aldolase-negative patients, dementia might have been caused by other mechanisms. Second, it is possible that the AD population is heterogeneous in terms of the immune system's participation. It is interesting to note that in other studies, when antibodies were found in AD patients the proportion of positive patients was similar to proportions described herein: around 50% (Fernandez-Shaw C. et al., 1997. J Neuroimmunol 77:91-98; Hyman et al., supra; Tanaka J. et al., 1989. Acta Neurol Scand 80:554-560). Third, in the example described herein, the antibody reactivity was tested at a single time point. It is possible that some of the samples that did not react with the 42 kDa band were taken a time point in which reactivity was lost as part of the determinant spreading mechanism operative in autoimmune diseases (James, J. A., and Harley, J. B., 1998. Immunol Rev 164:185- 200). Samples taken from the same patients at an earlier stage may have had a positive reaction.

Human tissues were tested to verify that the antibody detected to the rat tissue antigen was an autoantibody. As can be seen in Figure 2, the band was clearly present in human brain lysate and was absent from human liver and skin. Thus, the pattern of tissue reactivity was similar for rat and human tissues, indicating that the IgG antibody detected was an autoantibody.

Example 2: Identification of the 42 kDa band

To identify the 42 kDa antigen, the lysate of rat brain that showed the highest level of expression of the antigen was used. The lysate was subjected to anion exchange chromatography and the 42 kDa protein was found not to bind to quaternary ammonium

(mono Q Sepharose fast flow Pharmacia Biotechnology, LKB₅ Sweden). The band was then collected from the flow-through and lyophilized. In the next step, the lyophilized material was separated by PAGE. The 42 kDa band was excised from the gel and was subjected to in-gel digestion and mass spectrometry. The mass spectrometry detected 18 different peptides that together covered 39% of the rat Aldolase A sequence (Table 2,

Figure 3). The protein was identified by searching a comprehensive non-redundant protein database using the ProFound program (version 4.10.5, The Rockefeller University Edition). This finding identified the protein to be rat aldolase A with high degree of probability (probability l.Oe + 000; Z score 2.33). Aldolase A is conserved in evolution. The amino acid sequence of rate aldolase A (SEQ ID NO:1; gi6978487) is 97% identical to the sequence of rabbit Aldolase A (SEQ ID NO:2; gi34577112) and shows 96% identity to human aldolase A (SEQ ID NO:3; 113608). An alignment of these three sequences is shown in Figure 4.

To confirm that the serum reacted to intact aldolase A, purified rabbit muscle aldolase (Sigma) was used. Various amounts of the rabbit aldolase were run in a gel in parallel to the brain lysate. As can be seen in Figure 5, the serum obtained from AD patients stained a band of identical size in both the aldolase and tissue preparations.

Table 2: Mass spectrometry of 42 kDa band.

Example 3: ELISA assays for detecting anti-aldolase antibodies in a serum

To simplify the assay for antibody reactivity to aldolase, 45 sera samples of AD patient, 25 sera samples of normal elders and 30 samples of patients with multiple sclerosis were tested to rabbit aldolase in the ELISA assay. The wells were coated with 1 μg of aldolase and the sera (diluted 1/70 in 2% non-fat milk (Bio-Rad) in PBS) was incubated in PBS. 23 of the 45 patients suffering from AD showed positive reactivity to aldolase (Figure 6). There was a strong correlation between positive reaction in Western blot (42 kDa band) and positive ELISA reactivity to aldolase. Among the normal elders, only 1 of 25 patients showed low aldolase reactivity, and in the group of 30 multiple sclerosis patients 2 of 30 showed low positive reactivity. The differences in reactivity between AD and control groups were highly significant (mean ± SD; AD Patients, 0.719 ± 0.706; control elderly subjects, 0.26 ± 0.075; MS patients 0.33 ± 0.146; 2 tailed t test, p value of AD vs. MS was 0.00132; AD vs. elder controls was 0.00121).

It should be noted that the clinical diagnosis of Alzheimer's disease is not certain and definite diagnosis can only be made pathologically. Among patients with dementia, in various studies, 40-82% have Alzheimer's disease (Nussbaum and Ellis, supra).

Therefore, it is likely that some of the examined patients suffer from dementia related to other causes.

Example 4: Inhibition of enzyme activity by anti-aldoϊase positive serum

The effect of anti-aldolase antibodies on aldolase activity was measured as described in "material and methods" herein above. The reciprocal enzyme VO was calculated and plotted against the reciprocal of the substrate concentration (Lineweaver- Burke plot), and the change in Km was calculated. As shown in Figure 7, sera from AD patients inhibited aldolase enzyme activity causing an increase in Km from 0.435 mM to 0.869 mM (with serum from AD7) and 1.239 (with serum from AD45). This increase in Km is compatible with competitive inhibition of enzyme activity. A similar phenomenon of inhibition of enzymes by auto-antibodies to transglutaminase and mitochondrial M2 has previously been described (Esposito, C, F. et al., 2002. Gut 51:177; Schmit, P., G. et al., 1999. Clin Chem 45:2287). Example 5: Effect of added substrate on the binding of anti-aldolase antibodies to aldolase

To test the effect of the substrate fructose 1 ,6 diphosphate on antibody binding to aldolase, the ELISA assay was performed coating the enzyme in the substrate solution. Figure 8 shows that in all AD sera tested, the binding of anti-aldolase antibody was significantly enhanced by the addition of the substrate. Similar analysis of antibody binding in elderly controls did not show significant differences with relation to the presence of fructose 1 ,6 diphosphate. Crystallography studies have shown a significant conformational change in aldolase after binding fructose 1,6 biphosphate (Dalby, A., Z. et al., 1999. Protein Sci 8:291.). Thus, the AD antibodies may actually target the aldolase conformation induced by the binding of fructose 1,6 diphosphate. This finding can be interpreted to suggest that the in-vivo immune response to the enzyme was driven by the enzyme-substrate complex.

Example 6: Examination of side effects of immunization with aldolase in Lewis rat

To test whether induction of autoimmunity to aldolase might be pathogenic, Lewis rats were immunized with rabbit aldolase in CFA. Lewis rats were selected for this assay as they are known to be susceptible to several experimental autoimmune diseases (such as: adjuvant arthritis (Quintana F. J. et al., 2002. J Immunol 169:3422- 3428), experimental autoimmune encephalomyelitis (Mor, F., and Cohen, I. R., 1992. J Clin Invest 90:2447-2455), myocarditis (Li Y. et al., 2004. J Immunol 172:3225-3234), uveitis (Mor et al., 2003, supra) and others (Verhagen C. et al., 1999. Invest Ophthalmol Vis Sci 40:2191-2198). The immunized rats did not manifest clinical signs of muscle weakness or paralysis. Histological examination of various tissues (heart, muscle, liver, cerebrum, cerebellum, spinal cord) showed normal organ architecture without inflammation. T cell proliferation from immunized rats showed antigen-specific reactivity to aldolase (Figure 9). To test whether antibodies to aldolase were induced in the immunized rats the immuno-blot of rat tissue lysates was repeated with serum from aldolase-injected rat. As is shown in Figure 10, serum from aldolase-immunized rat detected a band of identical size. It is known that CNS pathology, absent in active autoimmunization, can be mediated by activated T-cell lines. However, an anti-aldolase T cell line of the ThI phenotype did not cause disease upon adoptive transfer (data not shown). Histological analysis of brain, spinal cord, muscle and heart of the rats after inoculation with the aldolase-specific T cell line did not show signs of inflammation.

To further test the pathogenic potential of aldolase immunization, six NOD and six C57BL mice were inoculated with aldolase in CFA (50 μg/mouse, with 200 ng pertussis toxin) injected intraperitoneally on the day of immunization and after 48 hrs.

NOD mice are known to spontaneously develop type I diabetes and thyroiditis.

Moreover, both NOD and C57BL mice are susceptible to experimental autoimmune encephalomyelitis. None of the mice developed clinical signs of CNS or muscle disease, and histological analysis of brain, spinal-cord, muscle and heart did not reveal signs of inflammation.

The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without undue experimentation and without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. The means, materials and steps for carrying out various disclosed functions may take a variety of alternative forms without departing from the invention.

Claims

1. A method for diagnosing Alzheimer's disease comprising: a. providing a sample from a subject; b. contacting the sample with aldolase or an active fragment thereof, under conditions such that an immune reaction can occur to form an antigen-antibody complex; c. determining the presence of anti-aldolase antibodies in said sample; wherein the presence of anti-aldolase antibodies in said subject's sample is indicative of Alzheimer's disease.

2. The method according to claim 1, wherein the presence of anti-aldolase antibodies is determined by a method selected from the group consisting of Western blot, ELISA, radioimmunoassay, and immunofluorescence assay.

3. The method according to claim 1, wherein determination of the presence of anti-aldolase antibodies in the sample further comprises: i. contacting the antigen-antibody complex with a detection antibody such that the detection antibody binds to said anti-aldolase-antibodies; and ii. detecting the binding of said detecting antibody to said anti-aldolase antibodies; wherein said binding of said detecting antibody to said anti-aldolase- antibodies is indicative of Alzheimer's disease.

4. The method according to claim 3, wherein the detection antibody further comprises at least one conjugated enzyme selected from the group consisting of horseradish peroxidase, alkaline phosphatase, urease, glucoamylase and β-galactosidase.

5. The method according to claim 1, wherein the aldolase is selected from the group consisting of aldolase A and aldolase C.

6. The method according to claim 1, wherein the sample is selected from the group consisting of blood, plasma, serum, serous fluid, saliva, urine and cerebrospinal fluid (CSF).

7. The method according to claim 1, wherein the subject is a human subject.

8. The method according to claim 7, wherein the human subject is selected from the group consisting of a subject displaying pathology resulting from Alzheimer's disease, a subject suspected of displaying pathology resulting from Alzheimer's disease, and a subject at risk of displaying pathology resulting from Alzheimer's disease.

9. The method according to claim 1, for diagnosing Alzheimer's disease selected from the group consisting of late onset Alzheimer's disease, early onset Alzheimer's disease, familial Alzheimer's disease and sporadic

Alzheimer's disease.

10. A kit for diagnosing Alzheimer's disease comprising an immobilized support, at least one type of aldolase or an active fragment thereof, and at least one detection antibody.

11. The kit according to claim 10, wherein the immobilized support is coated with the at least one aldolase or the active fragment thereof.

12. The kit according to claim 11, wherein the aldolase is selected from the group consisting of aldolase A and aldolase C.

13. The kit according to claim 10, wherein the kit comprises an enzyme-linked immunosorbent assay kit.

14. The kit according to 10, further comprising components selected from the group consisting of needles, sample collection tubes, microtiter plates, and instructions.

15. A method for assessing efficacy of a treatment of Alzheimer's disease in a patient comprising: a. determining a baseline amount of anti-aldolase antibodies in a first sample obtained from the patient before receiving the treatment; b. determining the amount of the anti-aldolase antibodies in a second sample obtained from said patient after receiving said treatment; wherein a change in the amount of said anti-aldolase antibodies is correlated with a positive treatment outcome.

16. A method for assessing efficacy of a treatment of Alzheimer's disease in a patient comprising: a. determining the amount of anti-aldolase antibodies in a sample obtained from a control population; b. determining the amount of anti-aldolase antibodies in a sample obtained from the patient after receiving the treatment; wherein a lack of significant difference between the amount of the anti- aldolase antibodies in the sample obtained from said patient compared to the amount of said anti-aldolase antibodies in the sample obtained from the control population indicates a positive treatment outcome.

17. The method according to any one of claims 15-16, wherein the anti-aldolase antibodies are directed against aldolase selected from the group consisting of aldolase A and aldolase C.

18. A method for treating Alzheimer's disease comprising modulating the immune response of a patient suffering from Alzheimer's disease towards aldolase.

19. The method according to claim 18, comprising inducing an immune response against at least one type of aldolase in a patient.

20. The method according to claim 19, wherein the immune response is actively induced by administering to the patient an immunogenic effective amount of at least one type of aldolase or an active fragment thereof.

21. The method according to claim 20 wherein the aldolase or fragment thereof is administered with an adjuvant that enhances the immune response to said aldolase or active fragment thereof.

22. The method according to claim 19, wherein the immune response is actively induced by administering to the patient an effective dose of a nucleic acid sequence encoding aldolase or an active fragment thereof, wherein the nucleic acid is expressed in the patient to produce an immunogenic amount of aldolase or active fragment thereof.

23. The method according to claim 19, wherein the immune response is passively induced by administering to the patient at least one type of anti- aldolase antibody or an active fragment thereof.

24. The method according to claim 19, wherein the immune response is passively induced by administering to the patient a nucleic acid sequence encoding an anti-aldolase antibody or an active fragment thereof, wherein the nucleic acid is expressed in the patient to produce a therapeutic amount of anti-aldolase antibodies.

25. The method according to claim 19 wherein the immune response is induced by removing T-cells from the patient, contacting the T-cells with aldolase or a peptide derived thereof under conditions in which said T-cells are primed, and reintroducing said T-cells in said patient.

26. The method according to claim 18, comprising suppressing an immune response against at least one type of aldolase in a patient.

27. The method according to claim 26, wherein the immune response is suppressed by administering a therapeutically effective amount of at least one type of anti anti-aldolase antibody peptide comprising at least part of an aldolase epitope.

28. The method according to claim 27, wherein the anti anti-aldolase peptide is selected from the group consisting of a soluble aldolase or an active fragment thereof; an antibody against anti-aldolase antibody; and a peptide capable of suppressing the synthesis of anti-aldolase antibody.

29. The method of claim 26, wherein the immune response is suppressed by T- cell vaccination with patient-derived aldolase-specific T cells.

30. The method of claim 26, wherein the immune response is suppressed by direct removal of circulating -anti-aldolase auto antibodies from the serum of a patient.