PL203431B1 - Pharmaceutical composition and use of an immunogenic agent - Google Patents

Description

Description of the invention The invention relates to a pharmaceutical composition and the use of an immunogenic agent effective in inducing an immune response comprising anti-Aβ antibodies for the preparation of a medicament for the treatment or prevention of a disease characterized by amyloid logs. Alzheimer's disease (AD) is a progressive disease that causes senile dementia. See generally Selkoe, TINS 16, 403-409 (1993); Hardy et al., WO 92/13069; Selkoe,J. Neuropathol. Exp. Neurol. 53, 438-447 (1994); Duff et al., Nature 373, 476-477 (1995); Games et al., Nature 373, 523 (1995). In general, the disease can be divided into two categories: late-onset, which appears in old age (from the age of 65), and early-onset, which develops before old age, i.e. between 35 and 60 years of age. In both types of disease, the pathology is the same, but the abnormalities appear to be much more serious and more extensive in cases where the disease begins at a younger age. The disease is characterized by two types of damage to the brain: senile plaques and neurofibrillary tangles. Senile plaques are areas of disorganized neuropil up to 150 µm wide with extracellular amyloid logs occurring in the center, visible during microscopic analysis of brain tissue sections. Neurofibrillary bundles are intracellular tau proteins consisting of two filaments wrapped in pairs around each other. The main component of platelets is a peptide called A ß or ß-amyloid peptide. Aβ-peptide is an internal 39-43 amino acid fragment of a precursor protein called amyloid precursor protein (APP). Several mutations of the APP protein have been associated with the occurrence of Alzheimer's disease. See e.g. Goate et al., Nature 349, 704 (1991) (valine 717 to isoleucine); Chartier Harlan et al., Nature 353, 844 (1991) (valine 717 to glycine); Murrell et al., Science 254, 97 (1991) (valine 717 to phenylalanine); Mullan et al., Nature Genet. 1, 345 (1992) (double mutation changing lysine E 595 - -methionine E 596 into asparagine E 595 -leucine E 596). These mutations are believed to cause Alzheimer's disease as a result of increased or altered processing of APP into Aß, in particular the processing of APP into increased amounts of long forms of Aß (i.e. Aß1-42 and Aß -1-43). Mutations in other genes, such as the presenilin genes, PS1 and PS2, are thought to indirectly affect APP processing by producing increased amounts of long forms of Aβ (see Hardy, TINS 20, 154 (1997) )). These observations indicate that Aβ, especially its long form, is a causal element in Alzheimer's disease. McMichael, EP 526511, proposed the administration of homeopathic doses (less than or equal to 10-2 mg/day) of Aβ to patients with pre-existing AD. In a typical human with about 5 liters of plasma, even the higher limit of this dose is expected to produce a concentration no greater than 2 pg/ml. The normal concentration of Aβ in human plasma is 50 - 200 pg/ml (Seubert et al., Nature 359, 325-327 (1992). Due to the fact that the dose proposed in EP 526511 does little to change the level of endogenous Aβ in the circulation and because EP 526511 does not recommend the use of an adjuvant, it seems unlikely that any therapeutic effect will occur. In contrast, the invention relates to the treatment or prevention of an amyloidogenic disease by administering Aβ or another immunogen to a patient under conditions that induce a favorable immune response in the patient. The invention relates to a pharmaceutical composition characterized by comprising an immunogenic agent effective in inducing an immune response comprising anti-Aβ antibodies in a patient and a pharmaceutically acceptable adjuvant, the agent being selected from the group consisting of (i) Aβ, (ii) a fragment of at least five contiguous amino acids of Aβ42 and (iii) a nucleic acid encoding (i) or (ii); and the adjuvant is selected from the group consisting of aluminum, aluminum hydroxide, aluminum phosphate, aluminum sulfate, 3-de-O-acylated monophosphorylated lipid A, M-CSF and GM-CSF, oil-in-water emulsions such as squalene or peanut oil , MF59, SAF, CpG, polymeric or monomeric amino acids such as poly(glutamic acid) or polylysine, muramyl peptides (e.g. N-acetylmuramyl-L-threonyl-D-isoglutamine (thr-MDP), N-acetylnormuramyl-L-alanyl-D-isoglutamine (nor-MDP), N-acetylmuramyl-L-alanyl-D-isoglutaminyl-L-alanine -2-(1'-2'dipalmitoyl-sn-glycero-3-hydroxyphosphoryloxy)ethylamine (MTP-PE), N-acetylglucosaminyl-N-acetylmuramyl-L-A1-D-isoglu-L-Ala-di- palmitoxypropylamide (DTP-DPP)) and other components of bacterial cell walls, such as trehalose dimycolinate (TDM), cell wall skeleton (CWS), MPL+CWS, saponin adjuvants (QS21), PL 203 431 B1 3 ISCOM (complexes immunostimulants), cytokines such as interleukins (IL-1, IL-2 and IL-12), macrophage colony-stimulating factor (M-CSF), tumor necrosis factor (TNF); and A ß42 has the natural human sequence: H 2 N-Asp-Ala-Glu-Phe-Arg-His-Asp-Ser-Gly-Tyr-Glu-Val-His-His-Gln-Lys-Leu-Val -Phe-Phe-Ala-Glu-Asp-Val-Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu-Met-Val-Gly-Gly-Val-Val-Ile-Ala-OH . Preferably, the agent is encapsulated in a particle. More preferably, the particle is a polylactide-polyglycolide (PLPG) copolymer particle. In a preferred embodiment, A ß is A ß43, A ß42, A ß41, A ß40 or A ß39. The Aβ fragment is preferably derived from the N-terminal half of Aβ. The A ß fragment preferably comprises A ß1-5, and more preferably is A ß1-5. Thus, more preferably the A ß fragment is A ß1-6, or A ß1-12. Preferably, the A ß fragment is selected from the group consisting of A ß1-5, A ß1-6, A ß1-12, A ß13-28, A ß17-28, A ß25-35, A ß33-42, A ß35-40 and A ß35-42. In a preferred embodiment, the composition contains at least 10 Pg, or at least 20 Pg of Aβ, or at least 50 Pg of Aβ, or at least 100 Pg of Aβ or a fragment thereof. The invention also provides the use of an immunogenic agent effective in inducing an immune response comprising anti-Aβ antibodies for the preparation of a medicament for the treatment or prevention of a disease characterized by amyloid logs in a patient, wherein the agent contains (i) Aβ, (ii) a fragment of at least five contiguous A ß42 amino acids; or (iii) a nucleic acid encoding (i) or (ii); and A ß42 has the natural human sequence: H 2 N-Asp-Ala-Glu-Phe-Arg-His-Asp-Ser-Gly-Tyr-Glu-Val-His-His-Gln-Lys-Leu-Val -Phe-Phe-Ala-Glu-Asp-Val-Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu-Met-Val-Gly- Gly-Val-Val-Ile-Ala-OH . In a preferred embodiment, the medicament further comprises a pharmaceutically acceptable adjuvant selected from the group consisting of aluminum, aluminum hydroxide, aluminum phosphate, aluminum sulfate, 3-de-O-acylated monophosphoryl lipid A, M-CSF and GM-CSF, oil in water such as squalene or peanut oil, MF59, SAF, CpG, polymeric or monomeric amino acids such as poly(glutamic acid) or polylysine, muramyl peptides (e.g. N-acetylmuramyl-L-threonyl-D-isoglutamine (thr-MDP), N-acetylnormuramyl-L-alanyl-D-isoglutamine (nor-MDP), N-acetylmuramyl-L-alanyl- -D-isoglutaminyl-L-alanine -2-(1'-2'di-palmitoyl-sn-glycero-3-hydroxyphosphoryloxy)ethylamine (MTP-PE), N-acetylglucosaminyl-N-acetylmuramyl-L-A1-D-isoglu-L-Ala-dipalmitoxypropylamide ( DTP-DPP)), or other bacterial cell wall components such as trehalose dimycolinate (TDM), cell wall skeleton (CWS), MPL+CWS, saponin adjuvants (QS21), ISCOM (immunostimulatory complexes), cytokines such such as interleukins (IL-1, IL-2 and IL-12), macrophage colony-stimulating factor (M-CSF), tumor necrosis factor (TNF). In a preferred embodiment, the agent is encapsulated in a particle, which is more preferably a polylactide-polyglycolide (PLPG) copolymer particle. In a preferred embodiment, A ß is A ß43, A ß42, A ß41, A ß40 or A ß39. Preferably, the Aβ fragment is derived from the N-terminal half of Aβ. In a preferred embodiment, the A ß fragment comprises A ß1-5. More preferably, the Aβ fragment is Aβ1-5, or Aβ1-6, or Aβ1-12. In a preferred embodiment, the Aβ fragment is selected from the group consisting of Aβ1-5, Aβ1-6, Aβ1-12, Aβ13-28, Aβ17-28, Aβ25-35, Aβ33-42, Aβ35-40 and Aß35-42. In a preferred embodiment, the amount of sc Aβ or fragment thereof is at least 10 Pg, or at least 20 Pg, or at least 50 Pg, or at least 100 Pg. Preferably the patient is a human. In a preferred embodiment, the disease is Alzheimer's disease. In another preferred use, the patient remains asymptomatic. In a preferred embodiment, the patient is less than 50 years of age. In another preferred embodiment, the patient has inherited risk factors indicative of susceptibility to Alzheimer's disease, and in another preferred embodiment, the patient has no known risk factors for Alzheimer's disease. In a more preferred use, Aß is present in aggregated form. Preferably, the drug is administered orally, subcutaneously, intramuscularly, topically or intravenously. More preferably, the drug is administered intramuscularly or subcutaneously. PL 203 431 B1 4 In a more preferred embodiment, the agent is an effective dose of a nucleic acid encoding Aβ or a fragment of at least five contiguous amino acids of Aβ42, wherein the nucleic acid is expressed in the patient to produce Aβ or a fragment of least five adjacent amino acids A ß42 causing an immune response. More preferably, the drug is administered topically. More preferably, the drug is applied topically in the form of a patch. In a more preferred use, the patient is monitored for immune response. Methods of preventing or treating diseases characterized by amyloid deposition in a patient result in the induction of an immune response against a peptide component of the amyloid logs in the patient. Such induction of a response may occur actively by administration of an immunogen, or passively by administration of an antibody or an active fragment or derivative of an antibody. In some patients with an amyloid log there is a concentration of A ß peptide and the disease is Alzheimer's disease. In some methods, the patient is asymptomatic. In some methods, the subject is over 50 years of age. In some methods, the patient has inherited risk factors indicating susceptibility to Alzheimer's disease. These risk factors include variable alleles of the PS1 and PS2 presenilin genes and variable forms of APP. In other methods, there are no known risk factors for Alzheimer's disease. In the treatment of patients suffering from Alzheimer's disease, one treatment approach involves administering a dose of Aβ-peptide to the patient to induce an immune response. Sometimes Aβ peptide is administered with an adjuvant that enhances the immune response to Aβ peptide. It could be a lun or MPL. The dose of Aβ-peptide administered to the patient is typically at least 1 or 10 µg when administered with adjuvant and at least 50 µg when administered without adjuvant. It may also be at least 100 µg. The Aβ peptide may also be Aβ1-42. Sometimes Aβ-peptide is administered in aggregated or dissociated form. The therapeutic agent may also be an effective dose of a nucleic acid encoding Aβ or an active fragment thereof or a derivative thereof. A nucleic acid encoding Aβ or a fragment thereof is expressed in a patient to produce Aβ or an active fragment thereof that induces an immune response. Sometimes nucleic acid is administered through the skin, possibly in the form of a patch. The therapeutic agent can be found by searching a library of compounds to identify a compound that interacts with Aβ antibodies and administering the compound to the patient to induce an immune response. The immune response may be directed against the Aβ peptide in the aggregated form rather than against the Aβ peptide in the dissociated form. For example, the immune response may consist of antibodies that bind the aggregated form of Aβ-peptide but do not bind the dissociated Aβ-peptide. The immune response may involve T cells binding Aβ complexed with MCHI or MCHII on CD8 or CD4 cells, or is induced by administration of an anti-Aβ antibody to the patient. An immune response can also be induced by harvesting T cells from a patient, exposing the T cells to Aβ-peptide under conditions in which the T cells are activated, and then reintroducing the T cells into the patient. The drug is usually administered orally, intranasally, intradermally, subcutaneously, intramuscularly, topically or intravenously. After administration of the drug, the patient can be monitored to determine the immune response. If during monitoring there is a decrease in the immune response over time, the patient may be given one or more subsequent doses of the drug. The pharmaceutical compositions may contain Aβ and an excipient suitable for oral administration and other routes, or an agent effective to induce an immune response against Aβ in a patient and a pharmaceutically acceptable adjuvant. The agent may sometimes be Aß or its active fragment. The adjuvant may be a solid powder, and sometimes it is an oil-in-water emulsion. Aβ or its active fragment may also be a component of a polylactide-polyglycolide copolymer (PLPG) or other particle. It is possible to combine Aβ or an active fragment thereof with a conjugate molecule to promote delivery of Aβ into the patient's bloodstream and/or promote an immune response against Aβ. The conjugate may, for example, promote the induction of an immune response against Aβ and may be cholera toxin, immunoglobulin, attenuated diphtheria toxin CRM 197 (Gupta, Vaccine 15, 1341-3 (1997)). The pharmaceutical composition may contain an agent effective to induce an immune response against Aβ in the patient, but the composition should not contain complete Freund's adjuvant. The agent may also contain a viral vector encoding Aβ or an active fragment thereof that effectively induces an immune response against Aβ. Suitable viral vectors may be: herpes virus, adenovirus, adeno-satellite virus, retrovirus, Sindibs virus, Semliki Forest virus, cowpox virus or avian pox virus. In methods for preventing and treating Alzheimer's disease, an effective dose of Aβ-peptide is administered to a patient. Aβ or antibodies directed against it can be used to produce a drug that prevents or treats Alzheimer's disease. You can also evaluate the effectiveness of a method of treating a patient's Alzheimer's disease. The basic amount of anti-Aβ antibodies in the patient's tissue samples is determined before the agent is administered. The amount of anti-Aβ-peptide specific antibodies in the patient's tissue samples after treatment with the agent can be compared to the basal amount of anti-Aβ-peptide-specific antibodies. The amount of anti-A ß peptide-specific antibodies measured after treatment, which is significantly higher than the basal amount of anti-A ß peptide-specific antibodies, indicates a positive treatment result. In assessing the effectiveness of methods for treating Alzheimer's disease in a patient, the basic amount of anti-Aß-specific antibodies can be determined in the patient's tissue samples before the agent is administered. The amount of anti-Aβ-peptide-specific antibodies in patient tissue samples after treatment with the agent can be compared to the basal amount of anti-Aβ-peptide-specific antibodies. A decrease in the amount or no significant difference between the amount of anti-Aβ peptide-specific antibodies measured after treatment and the basal amount of anti-Aβ peptide-specific antibodies indicates a negative treatment result. In another way to assess the effectiveness of the treatment of Alzheimer's disease in a patient, a control amount of anti-Aβ-specific antibodies can be determined in tissue samples from a control population. The amount of anti-Aβ-peptide-specific antibodies in the patient's tissue samples after treatment with the agent can be compared to a control amount of anti-Aβ-peptide-specific antibodies. The amount of anti-A ß peptide-specific antibodies measured after treatment, which is significantly higher than the control amount of anti-A ß peptide-specific antibodies, indicates a positive treatment result. In another way to assess the effectiveness of the treatment of Alzheimer's disease in a patient, a control amount of anti-Aβ-specific antibodies can be determined in tissue samples from a control population. The amount of anti-Aβ-peptide-specific antibodies in the patient's tissue samples after administration can be compared with a control amount of anti-Aβ-peptide-specific antibodies. The lack of a significant difference between the amount of anti-A ß peptide-specific antibodies measured after the start of treatment and the control amount of anti-A ß peptide-specific antibodies indicates a negative treatment result. Other methods of monitoring a patient for Alzheimer's disease or susceptibility to the disease may include detecting an immune response against Aβ-peptide in a sample obtained from the patient. Sometimes a patient is given a drug that is effective in treating or preventing Alzheimer's disease, and the level of response determines the patient's future treatment regimen. In another way of assessing the effectiveness of the treatment of Alzheimer's disease in a patient, it is possible to determine the amount of antibodies specific to the A-β peptide in a tissue sample of the patient treated with the agent. This amount can be compared with a control amount determined in a population of patients whose symptoms of Alzheimer's disease improve or disappear after treatment with the agent. A patient's value at least equal to the control value indicates a positive response to treatment. Kits for such assessments may typically contain a reagent that specifically binds to anti-Aβ antibodies or stimulates the proliferation of Aβ-reactive T cells. The invention will become more understandable from the attached drawings, Fig. Figure 1: Antibody titer after injection into A ß1-42 transgenic mice. Fig. 2: Hippocampal amyloid burden. Based on computer-assisted quantitative image analysis of immunoreactive brain areas, the percentage of the hippocampal region area occupied by amyloid plaques was determined, determined on the basis of reactivity with mA ß 3D6 specific for A ß. The values for individual mice are divided into study groups. The horizontal line for each group indicates the median value of the distribution. Fig. 3 Neuritic dystrophy in the hippocampus. Based on computer-assisted quantitative image analysis of immunoreactive brain areas, the percentage of the hippocampal region area occupied by degenerating le neurites was determined, determined by their interaction with human APP-specific mA ß 8E5. Values for individual mice are given for the group treated with AN1792PL 203 431 B1 6 and the control group treated with PBS. The horizontal line for each group indicates the median value of the distribution. Fig. 4 Astrocytosis in the extracallosal cortex. Based on computer-assisted quantitative image analysis of immunoreactive brain areas, the percentage of the cortical region area occupied by astrocytes positive for glial fibrillary acidic protein (GFAP) was determined. Values for individual mice are given by dividing them into study groups, and median values for groups are indicated by horizontal lines. Fig. 5 Geometric mean antibody titers against Aβ1-42 after immunization over a range of eight doses of AN1792 containing 0.14, 0.4, 1.2, 3.7, 11, 33, 100 or 300 µg. Fig. 6 Kinetics of the antibody response after AN1792 immunization. Titers were expressed as geometric mean values for 6 animals in each group. Fig. 7 Quantitative image analysis of cortical amyloid burden in mice exposed to PBS and AN1792. Fig. 8 Quantitative image analysis of neuritic plaque burden in mice exposed to PBS and AN1792. Fig. 9 Quantitative image analysis of the percentage of retrocallosal cortex affected by astrocytosis in mice exposed to PBS and AN1792. Fig. 10 Lymphocyte proliferation assay on spleen cells in mice exposed to AN1792 (upper graph) and PBS (lower graph). Fig. 11 Total Aß level in the cortex. Scatterplot of individual Aβ profiles in mice immunized with Aβ or APP derivatives in combination with Freund's adjuvant. Fig. 12 Cortical amyloid load was determined on the basis of computer-controlled quantitative image analysis of immunoreactive brain areas of mice immunized with A ß peptide conjugates - A ß1-5, A ß1-12, A ß13-28, full-length A ß aggregates of AN1792 ( A ß1-42) and AN1528 (A ß1-40) and the PBS-treated control group. Fig. 13 Geometric mean titers of Aβ-specific antibodies for groups of mice immunized with Aβ or APP derivatives in combination with Freund's adjuvant. Fig. 14 Geometric mean titers of Aβ-specific antibodies for groups of guinea pigs immunized with AN1792 or its palmitolated derivative in combination with various adjuvants. Fig. 15 Aβ levels in the cortex of 12-month-old PDAPP mice treated with AN1792 or AN1528, with different adjuvants. The term "substantially identical" means that two protein sequences, preferably aligned using programs such as GAP or BESTFIT using default gap weights, have at least 65 percent sequence identity, preferably at least 80 or 90 percent sequence identity, more preferably at least 95 percent sequence identity or more (e.g. 99 percent sequence identity or more). Preferably, residue positions that are not the same differ by substitution with conservative amino acids. When aligning sequences, one of the sequences is usually used as a reference sequence against which the sequences under study are compared. Using a sequence comparison algorithm, the test and reference sequences are entered into the computer, if necessary, the subsequence coordinates are determined, and then the parameters of the software algorithm are determined. The sequence comparison algorithm then calculates the percentage of identity of the test sequence(s) to the reference sequence based on the established program parameters. Optimal alignment of the compared sequences can be performed, e.g. using the local homology algorithm of Smith and Waterman, Adv. Appl. Math. 2:482 (1981), the homology matching algorithm of Needeleman and Wunsch, J. Moth. Biol. 48:443 (1970), looking for similarities with the methods of Pearson and Lipman, Proc. Natl. Acad. Sci. USA 85: 2444 (1988), using computerized versions of these algorithms (GAP, BESTFIT, FASTA and TFASTA in the Wisconsin Genetics Software Package, Genetics Computer Group, 575 Science Dr. , Madison, WI) or by visual inspection (see mainly Ausubel et al., supra). One example of an algorithm suitable for determining the percentage of sequence similarity and identity is the BLAST algorithm described by Altschul et al., J. Moth. Biol. 215:403-410 (1990). Software for performing the BLAST algorithm is publicly available through the National Center for Biotechnology Information (http://www. ncbi. nlm. nih. gov/). Typically, the default program parameters can be used to perform sequence comparison, but customized parameters can also be used. For amino acid sequences, the BLAST program uses as default a word length (W) of 3, an expectation (E) of 10 and a scoring matrix of BLOSUM62 (see Henikoff and Henikoff, Proc. Natl. Acad. Sci. USA 89, 10915 (1989)). For the purpose of classification based on n amino acids, conservative and non-conservative, amino acids are grouped as follows: Group I (hydrophobic, side chains): norleucine, met, ala, val, leu, ile; Group II (biethnic, hydrophilic side chains): cys, ser, thr; Group III (acidic, side chains): asp, glu; Group IV (basic, side chains): asn, gln, his, lys, arg; Group V (amino acids influencing the orientation of the chain): long, pro and Group VI (aromatic side chains): trp, tyr, phe. Conservative substitutions include substitutions between amino acids of the same class. Non-conservative substitutions include changes from an amino acid of one class to an amino acid of another class. The therapeutic agents contained in the compositions of the invention are typically substantially pure. This means that the agent is typically at least 50% (by weight) pure and is substantially free of interfering proteins or contaminants. Sometimes the compositions are at least 80% (by weight), more preferably at least 80 or about 95% (by weight) pure. However, using standard protein purification techniques, it is possible to obtain protein preparations that are at least 99% homogeneous. Specific binding of two units means an affinity of at least 106, 107, 108, 109M-1 or 1010M-1. Affinity values greater than 10 8 M -1 are preferred. The term "antibody" is used herein to refer to intact antibodies as well as their binding fragments. Typically, fragments compete for antigen binding with the intact antibodies from which they originate. Additionally, antibodies or their binding fragments may be chemically linked or expressed as fusion proteins with other proteins. APP 695, APP 751 and APP 770 refer to polypeptides of 695, 751 and 770 amino acids, respectively, encoded by the human APP gene. See Kang et al., Nature 325, 773 (1987); Ponte et al., Nature 331, 525 (1988), and Kitaguchi et al., Nature 331, 530 (1988). Amino acids within the human amyloid precursor protein (APP) are assigned numbers according to the sequence of the APP770 isoform. Terms such as Aβ39, Aβ40, Aβ41, Aβ42 and Aβ43 denote Aβ peptides containing amino acids 1-39, 1-40, 1-41, 1-42 and 1-43. The term "epitope" or "antigen determinant" means a place on an antigen to which B and/or T cells respond. B-cell epitopes can be formed from two adjacent or non-adjacent amino acids placed next to each other by a tertiary assembly of a protein. Epitopes formed from adjacent amino acids are usually retained upon exposure to denaturing solvents, whereas epitopes formed by tertiary splicing disappear upon exposure to denaturing solvents. An epitope typically includes at least 3, and more often at least 5 or 8-10 amino acids in a unique spatial conformation. Methods for determining the spatial conformation of epitopes include, for example: X-ray crystallography and two-dimensional nuclear magnetic resonance. See e.g. Epitope Mapping Protocols in Methods in Molecular Biology, vol. 66, ed. Glenn E Morris (1996). Antibodies recognizing the same epitope can be identified by a simple immunoassay showing the ability of one antibody to block the binding of another antibody to the target antigen. T cells recognize continuous epitopes of approximately 9 amino acids in length for CD8 cells or approximately 13-15 amino acids in length for CD4 cells. Epitope-recognizing T cells can be identified in in vitro assays measuring antigen-dependent proliferation, assayed by 3H-thymidine incorporation in sensitized T cells, in response to the epitope (Burke et al., J . Inf. Dis. 170, 1110-19 (1994)), antigen-dependent death (cytotoxic T-cell assay, Tigges et al., J. Immunol. 156, 3901-3910) or cytokine secretion. The term "immune" or a response with "immune" means the development of a favorable humoral (antibody-mediated) and/or cellular (mediated by antigen-specific T cells or their secretory products) response directed against the amyloid peptide in the recipient patient. . Such a response may be an active response triggered by the administration of an immunogen, or a passive response triggered by the administration of an antibody or sensitized T cells. The cellular immune response is triggered by the presentation of polypeptide epitopes in association with Class I or Class II MHC molecules to activate antigen-specific CD4+ helper T cells and/or CD8+ cytotoxic T cells. The response may also include activation of monocytes, macrophages, natural killer cells, basophils, dendritic cells, astrocytes, microglial cells, eosinophils, or other components of innate immunity. The occurrence of a cell-mediated immune response may be assessed by proliferation assays (CD4 + T cells) or CTL (cytotoxic T lymphocytes) assays (see Burke, PL 203 431 B1 8 supra; Tiggers, supra). The relative contributions of the humoral and cellular responses to the protective or therapeutic effect of an immunogen can be distinguished by separately isolating IgG and T cells from an immunized syngeneic animal and measuring the protective or therapeutic effect in the second animal. An "immunogenic agent" or "immunogen" is capable of eliciting an immune response against itself, optionally in combination with an adjuvant, upon administration to a patient. The term "naked polynucleotide" means a polynucleotide not complexed with a colloidal material. Naked polynucleotides are sometimes cloned into plasmid vectors. The term "adjuvant" means a compound which, when administered together with an antigen, enhances the immune response to the antigen, but when administered alone does not induce an immune response to the antigen. Adjuvants can enhance the immune response through several different mechanisms, including lymphocyte recruitment, B and/or T cell stimulation, and macrophage stimulation. The term "patient" means a human or other mammal undergoing prophylaxis or treatment. Disintegrated or monomeric Aβ means soluble, monomeric Aβ peptide units. One way to prepare monomeric Aß is to dissolve the lyophilized peptide in pure DMSO with ultrasonic disintegration of the compounds. The resulting solution is centrifuged to remove insoluble particles. Aggregated Aß is a mixture of oligomers in which the monomeric units are held together by non-covalent bonds. Means or methods "comprising" one or more of the enumerated elements may include other elements not specifically mentioned. For example, an Aβ-peptide containing agent includes both the isolated Aβ-peptide and the Aβ-peptide as a component of a longer polypeptide sequence. The invention relates to therapeutic agents and methods of preventing and treating diseases characterized by the accumulation of amyloid logs. Amyloid logs contain peptides aggregated into insoluble masses. The nature of the peptides varies in different diseases, but in most cases the aggregate has the structure of a β-folded sheet and is stained with Congo Red. Diseases characterized by amyloid logs include Alzheimer's disease (AD), both early and late onset. In both diseases, amyloid logs contain a peptide called Aß, which accumulates in the brain of sick people. Examples of other diseases characterized by amyloid logs are SAA amyloidosis, hereditary Iceland syndrome, multiple myeloma and spongiform encephalopathies, including mad cow disease, Jakob's Creutzfeldt disease, sheep encephalopathy and mink spongiform encephalopathy. (see Weissmenn et al., Curr. Opinion. Neurobiol. 7, 695-700 (1997); Smits et al., Veterinary Quarterly 19, 101-105 (1997)), Nathanson et al., Am. J Epidemiol. 145, 959-969 (1997)). The peptides that form aggregates in these diseases are, for the first three, serum amyloid A, cystantin C, IgG light chain - and prion proteins for the rest. The therapeutic agents contained in the pharmaceutical compositions according to the invention induce an immunological response against Aβ peptide. These agents include Aβ-peptide itself and variants, analogs and mimetics of Aβ-peptide that induce and/or cross-react antibodies against Aβ-peptide and antibodies or T cells reactive with Aβ-peptide. The induction of an immune response may be active, e.g. when an immunogen is administered to the patient to induce antibodies or T cells reacting with Aß, or passively, e.g. when the patient is given an antibody that binds Aβ itself. A ß also known as ß-amyloid peptide or A4 peptide (see US 4,666,829; Glenner and Wong, Biochem. Biophys. Res. Commun. 120, 1131 (1984), is a 39-43 amino acid long peptide that is the main component of the characteristic plaques in Alzheimer's disease. A ß is produced by the processing of the larger APP protein by two enzymes called ß and ? secretases. (Look. Hardy, TINS 20, 154 (1997)). Known mutations in APP associated with Alzheimer's disease occur proximal to sites ß or ? secretase or within Aß. For example, position 717 lies proximal to the site of APP cleavage by the secretase e? during processing to A ß, and positions 670/671 lie too proximal to the site of cleavage by ß secretase. Mutations are thought to cause AD by affecting the cleavage reactions that produce Aß, so that they increase the amount of the 42/43 amino acid form of Aß produced. Aß also has the extraordinary ability to perpetuate and activate both the classical and alternative complement cascades. In particular, it binds to Clq and ultimately to C3bi. This connection facilitates binding to macrophages, leading to the activation of B cells. Additionally, C3bi further degrades and binds to CR2 on B cells in a T cell-dependent manner, leading to a 10,000-fold increase in T cell activation. This mechanism causes Aß to produce a greater immune response than other antigens. The therapeutic agent contained in the pharmaceutical composition may be any naturally occurring form of Aβ-peptide, and particularly the human form of α-peptide (i.e., Aβ39, Aβ40, Aβ41, Aβ42, or Aβ43). The sequences of these peptides and their relationship to the precursor APP are shown in Fig. 1 in Hardy et al., TINS 20, 155-158 (1997). For example, A ß42 has the sequence: H 2 N-Asp-Ala-Glu-Phe-Arg-His-Asp-Ser-Gly-Tyr-Glu-Val-His-His-Gln-Lys-Leu-Val-Phe- Phe-Ala- Glu-Asp-Val-Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu-Met-Val-Gly-Gly-Val-Val-Ile-Ala-OH A ß41, A ß40 and A ß39 differ from A ß42 by omitting Ala, Ala-Ile and Ala-Ile-Val, respectively, at the C-terminus. Aß43 differs from Aß42 in the presence of a threonine residue at the C-terminus. The therapeutic agent may also be an active fragment or analogue of the natural Aβ peptide, containing an epitope that induces a similar protective or therapeutic immune response when administered to a human. Immunogenic fragments typically have a continuous sequence of at least 3, 5, 6, 10 or 20 contiguous amino acids of the natural peptide. Immunogenic fragments include A ß1-5, 1-6, 1-12, 13-28, 17-28, 25-25, 35-40 and 35-42. Fragments from the N-terminal half of Aβ are preferred in some methods. Analogues include allelic, species and induced variations. Analogs typically differ from naturally occurring peptides at one or more places, often by conservative substitutions. Analogs typically share at least 80 or 90% sequence identity with natural peptides. Some analogues also contain unnatural amino acids or modifications of the N- or C-terminal amino acids. Examples of unnatural amino acids are a, a-disubstituted amino acids, N-alkylamino acids, lactic acid, 4-hydroxyproline, α-carboxyglutamate, e-N,N,N-trimethyl-lysine, e-N-acetyllysine, O-phosphoserine, N-acetylserine, N- Formylmethionine, 3-methylhistidine, 5-hydroxylysine, α-N-methylarginine. The prophylactic or therapeutic effects of fragments and analogues can be selected using transgenic animal models, as described below. Aβ, its fragments, analogues and other amyloidogenic peptides can be synthesized by solid-phase peptide synthesis or by recombinant expression, or they can be obtained from natural sources. Automatic protein synthesizers are commercially available from many suppliers, such as Applied Biosystems, Foster City, California. Recombinant expression can be performed in bacteria such as E. coli, yeast, insect cells or mammalian cells. Recombinant expression procedures are described by Sambrook et al., Molecular Cloning: A Laboratory Manual (C. S H P Press, NY 2nd ed. , 1989). Some forms of A ß peptide are also commercially available (e.g. American Peptides Company, Inc. , Sunnyvale, CA and California Peptide Research, Inc. Napa, CA). Therapeutic agents also include longer polypeptides including, e.g. A ß peptide, active fragment or analogue together with other amino acids. For example, the Aβ peptide may be present in the inactive APP protein or a segment thereof, such as the C-100 fragment starting at the N-terminus of Aβ and extending to the APP terminus. Such polypeptides can be tested for their prophylactic or therapeutic effects in animal models as described below. The Aβ-peptide, analog, active fragment or other polypeptide may be administered in an associated form (ie, as an amyloid peptide) or in a dissociated form. Therapeutic agents also include multimers of monomeric immunogenic agents. In a further embodiment, an immunogenic peptide, such as Aβ, may be used as a viral or bacterial vaccine. The nucleic acid encoding the immunogenic peptide is introduced into the genome or episome of the virus or bacteria. Optionally, the nucleic acid is introduced in such a way that the immunogenic peptide is expressed as a secretory protein or a fusion protein with an external surface protein of a virus or a transmembrane protein of a bacterium, so that the peptide is exposed. Viruses or bacteria used in such methods should be non-pathogenic or attenuated. Suitable viruses include adenoviruses, HSV, cowpox and fowlpox. A fusion of the immunogenic peptide with HBsAg from HBV is particularly suitable. Therapeutic agents also include peptides and other compounds that do not necessarily share significant sequence similarity with Aβ but nevertheless act as Aβ mimetics and induce a similar immune response. You may know e.g. test for suitability any peptides or proteins forming β-pleated sheets. Anti-idiotypic antibodies may also be used against monoclonal antibodies against Aβ or other amyloidogenic peptides. Such anti-Id antibodies imitate the antigen and produce an immunological response to it (see Essential Immunology (ed. Roit, Blackwell Scientific Publications, Palo Alto, ed. 6) p. 181). PL 203 431 B1 10 It is also possible to test random libraries of peptides or other compounds for suitability. Combinatorial libraries can be generated for many types of compounds, which can be synthesized step-by-step. Such compounds include polypeptides, β-fold mimetics, polysaccharides, phospholipids, hormones, prostaglandins, steroids, aromatic compounds, heterocyclic compounds, benzodiazepines, oligomeric N-substituted glycines and oligocarbamates. Large combinatorial libraries of compounds can be constructed by the coded synthetic library method described in Affymax, WO 95/12608, Affymax, WO 93/06121, Columbia University, WO 94/0851, Pharmacopeia, WO 95/35503 and Scripps, WO 95/30642 (each of which is cited herein by reference for all uses). Peptide libraries can also be constructed using phage display methods. See e.g. Devlin, WO 91/18980. Initially, combinatorial libraries and other compounds are tested for suitability by determining their ability to bind to antibodies or lymphocytes (B or T) known to be specific for Aβ or other amyloidogenic peptides. For example, initial screening may be performed using any polyclonal sera or monoclonal antibodies against Aβ or other amyloidogenic peptides. The compounds identified in these studies are then further analyzed for their ability to induce antibodies or reactive lymphocytes against Aβ or other amyloidogenic peptides. For example, multiple dilutions of serum can be tested on microtiter plates previously coated with Aβ peptide and a standard ELISA can be performed to detect reactive antibodies to Aβ. The compounds can then be tested for their prophylactic or therapeutic effectiveness in transgenic animals predisposed to amyloidogenic disease, as described in the Examples. Such animals include, e.g. mice carrying the 717 APP mutation described by Games et al., supra, and mice carrying the Swedish APP mutation, such as those described by McConlogue et al., US 5,612,486 and Hsiao et al., Science 274, 99 (1996); Staufenbiel et al., Proc. Natl. Acad. Sci. USA 94, 13287-13292 (1997); Sturchler-Pierrat et al., Proc. Natl. Acad. Sci. USA 94, 13287-13292 (1997); Brochlet et al., Neuron 19, 939-945 (1997). The same research approach can be applied to other potential agents such as the Aβ fragments described above, Aβ analogues and longer Aβ-containing peptides. The therapeutic agents contained in the pharmaceutical compositions of the invention also contain antibodies that specifically bind Aβ. Such antibodies may be monoclonal or polyclonal antibodies. Some of these antibodies bind specifically to the aggregated form of Aβ and do not bind to the dissociated form. Some of them are related to the dissociated form, not related to the aggregated form. Some are associated with both aggregated and dissociated forms. Production of non-human monoclonal antibodies, e.g. mouse or rat, can be achieved, for example, by immunizing the animal with Aß. See Harlow and Lane, Antibodies, A Laboratory Manual (CSHP NY, 1988) (referenced here for all uses). Such an immunogen may be obtained from a natural source by peptide synthesis or recombinant expression. Humanized forms of murine antibodies can be created using recombinant DNA techniques by combining the CDR regions of non-human antibodies with human constant regions. See Queen et al., Proc. Natl. Acad. Sci. USA 86, 10029-10033 (1989) and WO 90/07861 (referenced herein for all applications). Human antibodies can be obtained by phage exposure methods. See e.g. Dower et al., WO 91/17271; McCafferty et al., WO 92/01047. These methods produce phage libraries whose members display various antibodies on their external surfaces. Antibodies are usually displayed as Fv or Fab fragments. Phages displaying antibodies with the required specificity are selected by enriching their affinity for Aß or its fragments. Human anti-Aβ antibodies can also be produced from non-human transgenic mammals carrying transgenes encoding at least a segment of the human immunoglobulin locus and an inactivated endogenous immunoglobulin locus. See Lonberg et al., WO93/12227 (1993); Kucherlapati, WO 91/10741 (1991) (each of which is incorporated herein by reference for all uses n). Human antibodies can be selected in competitive binding experiments or otherwise, as having the same epitope specificity as specific mouse antibodies. Such antibodies are particularly likely to exhibit the advantageous functional properties of murine antibodies. Human antibodies are polyclonal so that they can be obtained in the form of serum from patients immunized with the immunogenic agent. Furthermore, such polyclonal antibodies can be concentrated by affinity purification using Aβ or other amyloid peptide as the affinity reagent. PL 203 431 B1 11 Human or humanized antibodies can be designed to have an IgG, IgD, IgA or IgE constant region and any isotype, including IgG1, IgG2, IgG3 and IgG4. Ia 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 Fv, or as single antibody chains, in which the variable domains of the light and heavy chains are joined together by a spacer. The therapeutic agents contained in the pharmaceutical compositions of the invention also include Aβ-peptide binding T cells. For example, T cells can be activated against Aβ-peptide by expressing a human MHC class I gene and a human β-2-microglobulin gene from an insect cell line where the empty complex is formed on the cell surface and can bind Aβ-peptide . T cells that are exposed to the cell line become specifically activated against the peptide. See Peterson et al., US 5,314,813. Insect cell lines expressing MHC class II antigen can similarly be used to activate CD4 T cells. The preparation of therapeutic agents for the treatment of other amyloidogenic diseases is governed by the same or analogous principles. In general, the agents listed above for use in the treatment of Alzheimer's disease may also be used for the treatment of early-onset Alzheimer's disease associated with Down syndrome. In mad cow disease, prion peptide, its active fragments or analogues and anti-prion peptide antibodies are used instead of Aβ-peptide, its active fragments or analogues and anti-Aβ-peptide antibodies used in the treatment of Alzheimer's disease. In the treatment of multiple myeloma, IgG light chains and their analogues and antibodies against them are used, etc. in case of other diseases. Some immune-inducing agents contain the appropriate epitope to induce an immune response against amyloid logos, but are too small to be immunogenic. In this situation, the immunogenic peptide can be combined with a suitable carrier to facilitate the induction of an immune response. Suitable carriers include serum albumin, hemocyanin from the mollusk Fisurella. keyhole limpet), immunoglobulin molecules, thyroglobulin E, ovalbumin E, tetanus toxin or toxins from other pathogenic bacteria such as diphtheria, E. coli, cholera or H. pylori or attenuated toxin derivatives. Other vehicles for stimulating or enhancing the immune response include cytokines such as IL-1, IL-1α and β peptides, IL-2, αlNF, IL-10, GM-CSF, and chemokines such as M1P1α and β and RANTES . Immunogenic agents can also be combined with peptides that improve transport through tissues, as described in O'Mahony, WO 97/17613 and WO 97/17614. Immunogenic agents can be linked to carriers by chemical cross-linking. Techniques for linking the immunogen to the carrier include the formation of disulfide bridges using N-succinymidyl-3-(2-pyridylthio)propionate (SPDP) and succimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate (SMCC) ( if there is no thiol group in the peptide, it can be introduced by adding cysteine). These reagents form disulfide bonds between themselves and the cysteine residues of the peptide on one protein and an amide bond through the E-amide group of lysine or another free E-amine group in other amino acids. Many of these disulfide/amide bonding agents are described in Immun. Rev. 62, 185 (1982). Other difunctional coupling agents form thioethers rather than disulfide bridges. Many of these thioether formers are commercially available and include the reactive esters of 6-maleimidocaproic acid, 2-bromoacetic acid, 2-iodoacetic acid and 4-(maleimidomethyl)cyclohexane-1-carboxylic acid. The carboxyl groups can be activated by combining them with succinimide or the sodium salt of 1-hydroxyl-2-nitro-4-sulfonic acid. Immunogenic peptides can also be expressed as fusion proteins with carriers. The immunogenic peptide can be linked to the carrier at the N-terminus, C-terminus or in the middle. Additionally, multiple repeats of the immunogenic peptide may be present in the fusion protein. An immune response directed against amyloid logos can also be induced by administering nucleic acids encoding Aβ peptide or other peptide immunogens. Such nucleic acid may be DNA or RNA. The nucleic acid segment encoding the immunogen is typically linked to regulatory elements, such as a promoter and enhancer, that enable expression of the DNA segment in the patient's intended target cells. For expression in blood cells, which is required to induce an immune response, promoter and enhancer elements from immunoglobulin light and heavy chain genes or the promoter and enhancer of the CMV major intermediate are suitable for direct expression. The combined regulatory elements and coding sequences are often cloned into a vector. PL 203 431 B1 12 Many viral vector systems are available, including retroviral systems (see e.g. Lawrie and Tumin, Cur. Opinion. Genet. Develop. 3, 102-109 (1993)), adenoviral vectors (see e.g. Bett et al.,J. Virol. 67, 5911 (1993)), adeno-satellite virus vectors (see e.g. Zhou et al.,J. Exp. Med. 179, 1867 (1994)), viral vectors of the pox family including vaccinia virus, avipox virus, alphavirus viral vectors such as those derived from Sindibs and Semliki Forest viruses (see, e.g., Dubensky et al., J. Virol. 70, 508-519 (1996)) and wart viruses (Ohe et al., Human Gene Therapy 6, 325-333 (1995); Woo et al., WO 94/12692 and Xiao and Brandsma, Nucleic Acids. Res. 24, 2630-2622 1996)). The DNA encoding the immunogen or the vector containing it can be encapsulated in liposomes. Suitable lipids and related analogues are described in US 5,208,036, 5,264,618, 5,279,833 and 5,283,185. Vectors and DNA encoding the immunogen may also be adsorbed or bound to appropriate particulate carriers, such as, for example, polymethylmethacrylate, polylactates and poly(lactate-coglycolides), see e.g. McGee et al., J. Micro Encap. (1996). Gene therapy vectors or naked DNA can be delivered in vivo by administration to a specific patient, usually systemically (e.g. intravenously, intraperitoneally, intranasally, intragastricly, intradermally, intramuscularly, subcutaneously or by intracranial infusion) or topically (see e.g. US 5,399,346). DNA can also be administered using a gene gun. See Xiao and Brandsma, supra. DNA encoding the immunogen is deposited on the surface of microscopic metal beads. The microprojectiles are accelerated by a shock wave or expanded helium and penetrate the tissues to a depth of several cell layers. It is suitable e.g. The Accel™ Gene Delivery Device manufactured by Agacetus, Inc. Middleton WI. Furthermore, naked DNA may pass through the skin into the blood simply by applying the DNA to chemically or mechanically irritated skin (see WO 95/05853). In another embodiment, vectors encoding immunogens can be delivered to cells ex vivo, such as cells explanted from a single patient (e.g. lymphocytes, bone marrow aspirate, tissue biopsy) or universal donor hematopoietic stem cells, and then reimplant these cells into the patient, usually after selecting for cells that have the vector attached. Treatable patients include those at risk for the disease but who have not developed symptoms, as well as patients who have developed symptoms. When it comes to Alzheimer's disease, virtually everyone is at risk of developing Alzheimer's disease if he or she lives long enough. Therefore, the present methods can be used prophylactically in the general population without determining the risk of an individual patient. The present methods are particularly useful for patients with known genetic risk for Alzheimer's disease. Such patients include people who have relatives who have had the disease, as well as people whose risk is determined by analyzing genetic and biochemical markers. Genetic markers for risk of Alzheimer's disease include mutations in the APP gene, particularly mutations at position 717 and positions 670 and 671 called Hardy and Swedish mutations, respectively (see Hardy, TINS, supra). Other risk markers are mutations in the presenilin, PS1 and PS2 and ApoE4 genes, family history of AD, hypercholesterolemia or prior arterial disease. People currently suffering from Alzheimer's disease can be recognized by their characteristic dementia and by the presence of the risk factors described above. Additionally, many diagnostic tests are available to identify people with AD. These include measurements of CSF t and A ß42 levels. Elevated T levels and decreased A ß42 levels indicate the presence of sc AD. Patients with Alzheimer's disease can also be diagnosed according to the MMSE and ADRDA criteria, as described in the examples section below. In asymptomatic patients, treatment can be started at any age (e.g. 10, 20, 30). However, it is usually not necessary to start treatment until the patient is 40, 50, 60 or 70 years old. Treatment usually involves administering multiple doses over a period of time. Treatment can be monitored by determining antibody or activated T or B cell responses to the drug (e.g., A β-peptide) over time. If the response wanes, a stronger dose is indicated. For patients with potential Down syndrome, treatment may begin before birth by giving the drug to the mother, or soon after birth. In preventive applications, pharmaceuticals or drugs are administered to a patient susceptible to or at risk of a particular disease in an amount sufficient to eliminate or reduce the risk or delay the onset of the disease. In therapeutic applications, pharmaceuticals or drugs are administered to a patient who is suspected of having such a disease or who has already suffered from such a disease, in an amount sufficient to cure or at least partially e-PL 203 431 B1 13 partial inhibition of the symptoms of the disease and its complications. The amount appropriate to achieve this is defined as the therapeutically or prophylactically effective dose. In both treatment and prophylaxis modes, agents are usually administered in several doses until a sufficient immune response is achieved. Typically, the immune response is monitored and subsequent doses are administered when the immune response begins to wane. Effective dosages of the agents of the invention for the treatment of the conditions described above vary depending on a variety of factors, including the method of administration, the target site, the physiological condition of the patient, whether the patient is a human or an animal, other drugs being taken , and on whether the treatment is preventive or therapeutic. Typically the patient is a human, but in some diseases, such as mad cow disease, the patient may be a non-human mammal such as a cattle. Therapeutic doses should be titrated to optimize safety and effectiveness. The amount of immunogen depends on whether an adjuvant is also administered, with higher doses required in the absence of an adjuvant. The amount of SC immunogen to be administered is sometimes 1 to 500 Pg per patient, and more often 5 to 500 Pg per injection when administered to humans. Sometimes a higher dose of 1 - 2 mg per injection is used. Typically, when administered to humans, 10, 20, 50 or 100 µg per injection is used. Injection intervals could vary significantly from once a day to once a year, and up to once a decade. On any given day on which a dose of immunogen is administered, the dose is greater than 1 µg/patient, and usually greater than 10 µg/ml if an adjuvant is also administered, and greater than 10 µg/patient patient, and typically 100 µg/patient in the absence of adjuvant. The typical treatment regimen involves immunization followed by booster injections at 6-week intervals. Another treatment regimen involves immunization followed by booster injections at 1, 2 and 12 months. Another treatment regimen involves injections every 2 months for life. In addition, booster injections may be irregular and based on monitoring the immune response. For passive immunization with antibodies, doses range from 0.0001 to 100 mg/kg, and more often 0.01 to 5 mg/kg of the recipient's body weight. Doses of nucleic acids encoding immunogens range from 10 ng to 1 g, 100 ng to 100 mg, 1 µg to 10 mg or 30-300 µg of DNA per patient. Doses for infectious viral vectors range from 10 - 109 or more virions per dose. Agents for eliciting an immune response may be administered parenterally, topically, intravenously, orally, subcutaneously, intraperitoneally, intranasally or intramuscularly for prophylactic and/or therapeutic treatment. The most common route of administration is subcutaneous, but others may be equally effective. The next most common route is intramuscular injections. This type of injections is most often performed in the muscles of the arms or legs. So, intravenous injections, as well as intraperitoneal, intraarterial, intracranial or intradermal injections are effective in generating an immune response. In some methods, the agents are injected directly into the specific tissue where the logs have accumulated. Additionally, agents of the invention may be administered in combination with other agents that are at least partially effective in treating amyloidogenic disease. In the case of Alzheimer's disease and Down syndrome, where amyloid logs occur in the brain, the agents of the invention may be administered in combination with other agents improving the penetration of the agents of the invention across the blood-brain barrier. Immunogenic agents of the invention, such as peptides, are sometimes administered in combination with an adjuvant. Many different adjuvants can be used in combination with a peptide such as Aβ to induce an immune response. Preferred adjuvants enhance the internal response to the immunogen without causing conformational changes in the immunogen that would affect the quality of the response. Preferred adjuvants include a lun, de-O-acylated monophosphorylated lipid A (MPL) (see GB 2220211). QS21 is a triterpene glycoside or saponin isolated from the bark of the Quillaja Saponaria Molina tree growing in South America (see Kensil et al., in Vaccine Design: The Subunit and Adjuvant Approach (ed. Powell and Newman, Plenum Press, NY, 1995); United States Patent No. 5,057,540). Other adjuvants include oil-in-water emulsions (e.g. squalene or peanut oil), optionally in combination with immunostimulants such as monophosphorylated lipid A (see Stoute et al., N. Engl. Med. 336, 86-91 (1997)). Another adjuvant is CpG (Bioworld Today, November 15, 1998 ). Furthermore, Aß may be conjugated to an adjuvant. For example, a lipopeptide version of Aβ can be obtained by conjugating palmitic acid or other lipids directly to the N-terminus of Aβ as described for hepatitis B antigen vaccines (Livingston, J. Immunol. 159, 1383-1392 (1997)). However, such conjugation should not substantially change the conformation of A ß so that it would also affect the nature of the response to it. Adjuvants may be administered as a component of the therapeutic agent together with the active agent or separately, before, simultaneously with, or after administration of the therapeutic agent. A preferred class of adjuvants are aluminum salts such as aluminum hydroxide, aluminum phosphate, aluminum sulfate. Such adjuvants may be used with or without other specific immunostimulants, such as MPL or 3-DMP, QS21, polymeric or monomeric amino acids such as polyglutamic acid or polylysine. Another class of adjuvants are oil-in-water emulsion preparations. Such adjuvants may be used with or without other specific immunostimulants, such as muramyl peptides (e.g., N-acetylmuramyl-L-threonyl-D-isoglutamine (thr-MDP), N-acetylnormuramyl-L-alanyl-D-isoglutamine (nor-MDP), N-acetylmuramyl-L-alanyl-D-isoglutaminyl-L- alanine-2-(1'-2'dipalmitoyl-sn-glycero-3-hydroxyphosphoryloxy)ethylamine (MTP-PE), N-acetyl-glucosaminyl-N-acetylmuramyl-L-Al-D-isoglu-L-Ala-dipalmitoxypropylamide (DTP-DPP) tera- mid™) or other components of bacterial cell walls. Oil-in-water emulsions include (a) MF59 (WO 90/14837), containing 5% squalene, 0.5% Tween 80 and 0.5% Span 85 (optionally containing various amounts of MTP-PE) in the form submicron particles formed using a microfluidizer such as a Model 110Y microfluidizer (Microfluidics, Newton MA), (b) SAF, containing 10% squalene, 0.4% Tween 80, 5% Pluronic L121 block polymer, and thr-MDP , prepared as a submicron emulsion by microfluidization or vortexed to produce an emulsion of larger particle sizes, and (c) Ribi™ adjuvant system (RAS), (Ribi Immunochem, Hamilton, MT) containing 2% squalene, 0.2% Tween 80 and one or more bacterial cell wall components from the group consisting of monophosphoryl lipid A (MPL), trehalose dimycolinate (TDM) and cell wall skeleton (CWS), preferably MPL+CWS (Detox ™). Another class of preferred adjuvants are saponin adjuvants such as Stimulon™ (qs21, Aquila, Worcester, MA) or particles made therefrom such as ISCOM (immunostimulatory complexes) and ISCOMATRIX. Other adjuvants include complete Freund's adjuvant (CFA) and incomplete Freund's adjuvant (IFA). Other adjuvants include cytokines such as interleukins (IL-1, IL-2 and IL-12), macrophage colony-stimulating factor (M-CSF), tumor necrosis factor (TNF). The adjuvant may be administered with the immunogen in one preparation before, simultaneously with, or after administration of the immunogen. The immunogen and adjuvant may be packaged and provided in the same vial or may be placed in separate vials and mixed prior to use. The immunogen and adjuvant are usually packaged with a label indicating the intended therapeutic use. If the immunogen and adjuvant are packaged separately, the package will usually include instructions for mixing before use. The choice of adjuvant and/or carrier depends on the stability of the adjuvanted vaccine, the route of administration, the dosing schedule, and the effectiveness of the adjuvant in the vaccinated species and in humans. A pharmaceutically acceptable adjuvant is one that has been approved or is acceptable for administration to humans by the appropriate regulatory authority. For example, Freund's complete adjuvant is not suitable for administration to humans. A lun, MPL and QS21 are favourable. Optionally, one or more adjuvants may be used simultaneously. Preferred combinations include a lun with MPL, a lun with QS21, MPL with QS21, and a lun, QS21 and MPL together. Additionally, Freund's incomplete adjuvant (Chung et al., Advanced Drug Delivery Reviews 32, 173-186 (1998)) may be used, optionally in combination with any ingredient selected from lunu, QS21 and MPL and all combinations thereof. The compositions of the invention are often administered as pharmaceutical compositions containing the therapeutically active agent and various pharmaceutically acceptable ingredients. See Remington's Pharmaceutical Science (ed. 15, Mack Publishing Company, Easton, Pennsylvania, 1980). The preferred form depends on the intended route of administration and therapeutic use. The compositions may also contain, depending on the formulation required, pharmaceutically acceptable, non-toxic carriers or diluents, which are defined as carriers commonly used in the formulation of pharmaceutical compositions for administration to humans and animals. etom. The diluent is selected so that it does not affect the biological activity of the agent. Examples of such diluents are distilled water, phosphate-buffered saline, Ringer's solution, dextrose solution and Hank's solution. Furthermore, the pharmaceutical agent or preparation may also contain other carriers, adjuvants or non-toxic, non-therapeutic, non-immunogenic stabilizers and the like. However, some reagents suitable for administration to animals, such as Freund's complete adjuvant, are not usually included in human formulations. PL 203 431 B1 15 Pharmaceuticals may also contain large, slowly metabolized macromolecules such as proteins, polysaccharides, polylactic acids, polyglycolic acids and copolymers (such as latex-functionalized sepharose, agarose, cellulose, etc. . ), polymeric amino acids, amino acid copolymers and lipid aggregates (such as oil droplets or liposomes). These carriers may also act as immunostimulants (i.e. adjuvants). For parenteral administration, the compositions of the invention may be administered as injectable doses of solutions or suspensions of the substances in a physiologically acceptable diluent with a pharmaceutical carrier which may be a sterile liquid such as water, oils, saline, glycerin or ethanol. Additionally, auxiliary substances such as wetting or emulsifying agents, surfactants, pH buffering substances, etc. may be present in the preparations. Other ingredients of pharmaceuticals include those derived from petroleum, animal, plant or synthetic sources, e.g. peanut oil, soybean oil and mineral oil. Generally, glycols such as propylene glycol or polyethylene glycol are preferred liquid carriers, especially for injectable solutions. Typically, they are prepared as injectable preparations, as liquid solutions or suspensions; It is also possible to prepare solid forms suitable for dissolving or dispersing in liquid vehicles prior to injection. The formulation may also be emulsified or encapsulated in liposomes or microparticles such as polylactide, polyglycolide or copolymer to enhance the action of the adjuvant, as described above (see Langer, Science 249, 1527 (1990) and Hanes, Advanced Drug Delivery Reviews 28, 97-119 (1997). The agents of the invention may also be administered as depot injections or as implant preparations, which may be prepared in such a way as to enable sustained or pulsed release of the active ingredient. Additional formulations suitable for other modes of administration include oral, intranasal and intravenous formulations, suppositories and transdermal formulations. In the case of suppositories, binders and carriers include e.g. polyalkylene glycols or triglycerides; such suppositories can be prepared from mixtures containing the active ingredient in an amount from 0.5% to 10%, preferably 1%-2%. Oral preparations contain excipients such as mannitol, lactose, starch, magnesium stearate, sodium saccharin, cellulose and pharmaceutical grade magnesium carbonate. These agents are in the form of solutions, suspensions, tablets, pills, capsules, delayed-release preparations or powders and contain as much as 10%-95% of the active ingredient, preferably 25%-70%. Topical administration can be achieved via a transdermal or intradermal route. Topical administration may be favored by simultaneous administration of cholera toxin or its detoxified derivatives or subunits, or similar bacterial toxins (see Glenn et al., Nature 391, 851 (1998)). Co-administration can be achieved by using the ingredients in a mixture or combined molecules obtained by chemical cross-linking or expression of a fusion protein. Alternatively, transdermal delivery can be achieved using skin patches or transferosomes (Paul et al., Eur. J Immunol. 25, 3521-24 (1995); Cevc et al., Biochem. Biophys. Acta 1368, 201-15 (1998)). It is possible to detect an immune response against Aβ peptide in a patient suffering from or susceptible to Alzheimer's disease. Such methods are particularly useful for monitoring the course of treatment administered to a patient. The methods can be used to monitor both therapeutic treatment in patients who develop symptoms and prophylactic treatment in patients who do not develop symptoms. It is possible to determine the value of the patient's basic immune response before administering a dose of the agent and compare it with the value of the immune response after treatment. A significant increase (that is, greater than the typical margin of error experienced in repeated measurements of the same sample, expressed as one standard deviation from the mean of these measurements) in the value of the immune response signals a positive treatment outcome (i.e. that administration of the agent induced or enhanced an immune response a). If the value of the immune response does not change significantly or decreases in strength, it indicates a negative treatment result. Generally, in patients initially treated with the agent, an increase in the immune response is expected after subsequent doses, which may eventually reach a plateau. Generally, administration of the agent is continued as the immune response increases. Reaching a plateau indicates that treatment may no longer be continued or the dose or frequency of administration may be reduced. It is also possible to establish a control value (i.e. mean with standard deviation) of the immune response for the control population. Typically, people in the control population had not received any prior treatment. The values of the immune response measured in the patient after administration of the therapeutic agent are compared with the control value. A significant increase compared to the control value (that is, greater than one standard deviation from the mean of these measurements) signals a positive treatment result. No significant increase or decrease indicates a negative treatment result. Generally, administration of the agent is continued until the immune response begins to increase relative to the control value. As before, reaching a plateau relative to control values indicates that treatment may be continued or the dose or frequency of administration may be reduced. Control value of the immune response (e.g. mean and standard deviation) can also be determined from a control population of individuals who have undergone treatment with the drug and whose immune responses have plateaued in response to treatment. The values of the immune response measured in the patient are compared with the control value. If the patient's measured level does not differ significantly (e.g. more than one standard deviation) from the control value, treatment may not be continued. If the patient's level is significantly below the control value, further administration of the agent is indicated. If the patient's levels remain below the control value, a change in treatment regimen may be indicated, e.g. use of another adjuvant. A patient who is not currently on treatment but has completed a period of treatment may also be monitored for immune response to determine whether resumption of treatment is required. The value of the immune response measured in the patient can be compared with the value of the immune response previously achieved in the patient during the treatment period. A significant reduction compared to previous measurements (that is, greater than the typical margin of error in repeated measurements of the same sample) indicates that treatment should be resumed. Furthermore, the value measured in the patient can be compared with a control value (mean plus standard deviation) determined for the patient population after completing the treatment period. In addition, the values measured in the patient can be compared with a control value in a population of patients treated prophylactically who did not develop symptoms of the disease or treated therapeutically and who improved the characteristics of the disease. In all these cases, a significant reduction relative to control levels (that is, greater than z standard deviation) indicates that the patient's treatment should be resumed. The tissue collected from the patient for analysis is usually blood, plasma, serum, mucus or cerebrospinal fluid. The sample is analyzed for indicators of immune response to any form of Aβ-peptide, typically Aβ42. The immune response can be determined based on the presence, e.g. l antibodies or T cells that specifically bind A β-peptide. The ELISA methods used to detect antibodies that specifically bind Aβ-peptide are described in the Examples section. Methods for detecting reactive T cells have been described above (see Definitions). Diagnostic kits can be prepared to implement the diagnostic methods described above. Typically, such kits contain an agent that specifically binds anti-Aβ antibodies or reacts with Aβ-specific T cells. The set may also include a tag. For the detection of anti-Aβ antibodies, the label is usually in the form of labeled anti-idiotypic antibodies. For antibody detection, an agent previously bound to the solid phase can be provided, such as wells in a microtiter plate. For the detection of reactive T cells, the label can be provided as 3H-thymidine to measure the proliferative response. The kits usually contain labels with instructions on how to use the kit. The label may also include a graph or other form correlating the levels of the measured tracer with anti-Aβ antibodies or Aβ-reactive T cells. The term label refers to any written or recorded material included with or otherwise accompanying the kit at any time during its manufacture, transportation, sale and use. For example, the term label includes advertising leaflets and brochures, packaging materials, manuals, audio and video cassettes, computer disks, as well as inscriptions printed directly on the kits accompanying the kit at any time during its manufacture, transport, sale and use. For example, the term label includes advertising leaflets and brochures, packaging materials, manuals, audio and video cassettes, computer disks, as well as inscriptions printed directly on the sets. EXAMPLES I. Preventive efficacy of Aβ against AD These examples describe the administration of Aβ42 peptide to transgenic mice overexpressing APP with a mutation at position 717 (APP 717V—F), predisposing them to the development of Alzheimer's neuropathology. The preparation and characterization of these mice (PDAPP mice) are described in Games et al., Nature, supra. In these animals, in the form of heterozygotes, Aß begins to accumulate from the age of 6 months. At the age of 15 months, they show log levels of Aß comparable to those observed in Alzheimer's disease. PDAPP mice were injected with either aggregated Aβ42 (aggregated Aβ42) or phosphate-buffered saline. Aggregated Aβ 42 was selected due to its ability to induce antibodies to multiple Aβ epitopes. AND. Methods 1. Source of mice Thirty heterogeneous female PDAPP mice were randomly divided into the following groups: 10 mice injected with aggregated A ß 42 (one died in transport), 5 mice injected with PBS/adjuvant or PBS, and 10 control mice no injections were given. Five mice were injected with ethos of plasma amyloid protein (SAP). 2. Preparation of immunogens Preparation of aggregated A ß 42: 2 mg A ß 42 (US Peptides Inc, batch K-42-12) was dissolved in 0.9 ml of water and adjusted to 1 ml by adding 0.1 ml of 10xPBS. The mixtures were then vortexed and incubated overnight at 37°C under conditions in which the peptide aggregates. Any unused Aβ was stored as a dry lyophilized powder at -20°C until the next injection. 3. Preparation of injections 100 µg of aggregated A ß 42 in PBS per mouse was emulsified in a 1:1 ratio with complete Freund's adjuvant (CFA) in a final volume of 400 µl of emulsion for the first immunization, and then a booster dose of this was administered. same amount of immunogen in incomplete Freund's adjuvant (IFA) after 2 weeks. Two additional doses of IFA were administered at 1-month intervals. Subsequent immunizations were performed at monthly intervals in 500 μl of PBS. Injections were performed intraperitoneally (i. Mr. ). PBS injections were administered in the same order and the mice were injected with the 1:1 PBS/adjuvant mixture at a volume of 400 μl per mouse or 500 μl of PBS per mouse. SAP injections were similarly administered in the same order using doses of 100 μg per injection. 4. Mouse blood titration, tissue preparation and immunohistochemistry The above methods are described in General Materials and Methods below. B Results PDAPP mice were administered aggregated A ß 42 (aggregated A ß 42), SAP peptides or phosphate-buffered saline. One group of mice was treated as a positive control and did not receive injections. Titers from mice in the aggregated Aβ 42 group were monitored each month from the fourth booster until the mice reached one year of age. Mice were sacrificed at the age of 13 months. At all time points tested, 8 of 9 mice in the aggregated Aβ 42 group developed high antibody titers, which remained high throughout the series of injections (titers greater than 1/10,000). The ninth mouse had a low but measurable titer of approximately 1/1000 (Fig. 1, table 1). Mice injected with etho SAPP had titers of 1:1000 to 1:30000 against this immunogen, with only one mouse having a titer exceeding 1:100000. Titers against aggregated Aβ42 were measured in mice treated with PBS at 6, 10 and 12 months of age. Titers against aggregated A ß 42 in PBS mice at 1/100 dilutions were only 4 times the baseline value at one data point and were less than 4 times the baseline value at the remaining data points (Table 1). The SAP-specific response was negligible at these time points and all titers were less than z 300. Seven of nine mice in the aggregated Aβ1-42 group had no detectable amyloid in their brains. However, brain tissue from mice in the SAP and PBS groups contained many 3D6-positive amyloid logs in the hippocampus, as well as in the frontal and cingulate cortices. The pattern of logs was similar to that of untreated control mice, with the characteristic presence of damage-sensitive subregions such as the outer molecular layer of the hippocampal gyrus embassy. One of the mice from the group administered A ß1-42 had a significantly reduced amyloid burden bordering the hippocampus. An isolated plaque was identified in another mouse treated with Aβ1-42. Quantitative image analysis of hippocampal amyloid load showed a significant reduction in the agni eta axis in animals treated with AN1792 (Fig. 2). The median amyloid load values for the PBS group (2.22%) and for the untreated control group (2.65%) were significantly higher than for mice immunized with AN1792 (0.00%, p =0.0005). However, the median sc value for the group immunized with SAP peptides (SAPP) is 5.74%. The brain tissue of untreated control mice contained abundant Aβ logs, revealed by the Aβ-specific monoclonal antibody (mAb) 3D6, in the hippocampus and also in the extracallosal cortex. A similar pattern of amyloid logs was also observed in mice immunized with SAPP or PBS (Fig. 2). Moreover, in all three latter groups, a significant proportion of damage-sensitive brain subregions classically observed in AD, such as the outer molecular layer of the hippocampal gyrus embassy, was observed. Brains that lacked Aβ logs also lacked the neuritic plaques typically seen in PDAPP mice with the human anti-APP 8E5 antibody. All brains from the remaining groups (injected with SAP, PBS or not injected) contained many neuritic plaques typical of untreated PDAPP mice. A small number of neuritic plaques were present in one of the AN1792-treated mice, and a single cluster of dystrophic neurites was found in the second AN1792-treated mouse. Image analysis for the hippocampus, shown in Fig. 3, showed the actual elimination of dystrophic neurites in mice treated with AN1792 (median 0.00%) compared to PBS recipients (median 0.28%, p=0.0005). Astrocytosis, a characteristic of the inflammation accompanying plaques, did not occur in the brains of the group administered A ß1-42. The brains of mice from other groups contained significant numbers of clustered GFAP-positive astrocytes typical of Aβ-associated gliosis. Some of the GFAP-reactive histological preparations were counterstained with Thioflavin a S to localize Aß from the logs. GFAP-positive astrocytes were associated with Aβ platelets in SAP, PBS, and untreated control mice. No such association was found in platelet-negative mice treated with Aβ1-42, whereas minimal platelet-associated gliosis was observed in one of the AN1792-treated mice. Image analysis, shown in Fig. 4 for the retrocallosal cortex, confirmed that the reduction in astrocytosis was significant, with a median value of 1.56% for mice treated with AN1792 compared to median values greater than 6% for groups immunized with SAP peptides, PBS or untreated ( p=0.0017). Data from a subset of Aβ1-42 and PBS mice showed a lack of platelet-associated MHC II immunoreactivity in Aβ1-42 mice, consistent with the absence of an Aβ-related inflammatory response. Fragments of mouse brains were treated with mAβs specific for MAC-1, a cellular surface protein. MAC-1 (CD11b) is a member of the integrin family and exists as a heterodimer with CD18. The CD11b/CD18 complex is present on monocytes, macrophages, neutrophils and NK cells (Mak and Simard). The MAC-1-reactive cell type found in the brain is most likely microglia, based on the similar morphology and phenotype in MAC-1 immunoreactive fragments. Platelet-associated MAC-1 labeling was lower in the brains of AN1792-treated mice compared to the PBS control group, an observation consistent with the absence of an Aβ-related inflammatory response. C Conclusions The lack of Aβ plaques and reactive neuronal and glial changes in the brains of mice administered Aβ1-42 indicate that amyloid is not accumulated in their brains, or that its minimal amount is accumulated, and that no pathological consequences such as gliosis and neurite pathology occurred. PDAPP mice treated with Aβ1-42 showed essentially the same lack of pathology as control non-transgenic mice. Thus, injections of Aß1-42 are very effective in preventing or clearing brain tissue of the human form of Aß and in eliminating subsequent neuronal or inflammatory degenerative changes. Therefore, administration of Aβ-peptide has therapeutic benefits in the prevention of AD. II. Dose-response studies Groups of 5-week-old female Swiss Webster mice (N=6 per group e) were immunized intraperitoneally with 300, 100, 33, 3.7, 1.2, 0.4 or 0.13 µg of A ß prepared in CFA/IFA. Three doses were given two weeks apart, followed by a fourth dose one month later. The first dose was emulsified with CFA, and the remaining doses were emulsified with IFA. Blood was collected from the animals for titer measurement 4-7 days after each immunization, starting after the second dose. Blood was additionally collected from animals from the set of three groups, immunized with 11, 33 or 300 µg of antigen, at approximately monthly intervals for 4 months after the fourth immunization in order to monitor the disappearance of the antibody response in various ranges of vaccine doses. These animals received five additional immunizations 7 months after the start of the study. The animals were sacrificed one week later to measure the antibody response to AN1792 and perform toxicological analysis. PL 203 431 B1 19 At doses from 300 to 3.7 µg, a decreasing response was observed with dose, and at the two lower doses no response was observed. The average antibody titer values were approximately 1:1000 after three doses and approximately 1:10000 after four doses of 11-300 μg of antigen (see Fig. 5). Antibody titers increased significantly after the third immunization for all groups except the lowest dose group, with GMT increases ranging from 5 to 25 times. Low antibody responses were then detected even in recipients of 0.4 µg doses. The 1.2 and 3.7 µg groups had comparable titers with a GMT of approximately 1,000, and the four highest doses grouped together with a GMT of approximately 25,000, except for the 33 µg dose group with a lower GMT of 3,000 . After the fourth immunization, the increase in titer was more moderate for all groups. A clear dose response was observed in the lower antigen dose groups from 0.14 µg to 11 µg, ranging from undetectable antibodies for 0.14 µg recipients to a GMT of 36,000 for 11 µg recipients. Again, the titers of the four highest groups from 11 to 300 µg clustered together. Therefore, for two consecutive immunizations, the antibody titer depends on the antigen dose in a wide range from 0.4 to 300 μg. After the third immunization, titers from the highest four-dose groups were comparable and remained as a plateau after additional immunization. One month after the fourth immunization, titers were 2- to 3-fold higher in the 300 μg group than those measured in blood collected 5 days after immunization (Fig. 6). This observation suggests that the peak anamnestic antibody response occurred later than 5 days after immunization. A smaller (50%) increase was observed during this time for the 33 µg group. In the 300 µg dose group, two months after the last dose, GMT gradually decreased by approximately 70%. After another month, the antibody titer decreased less rapidly, by 45% (100 µg) and by approximately 14% for the 33 and 11 µg doses. Therefore, the rate of decline in circulating antibody titers after cessation of immunization is biphasic, with a sharp decline in the first month after the peak response followed by a more gentle decline. The antibody titers and response kinetics of these Swiss Webster mice were similar to those of young, heterozygous, PDAPP transgenic mice immunized in a similar manner. Doses effective in inducing an immune response in humans are typically similar to those effective in mice. III. Search for therapeutically effective agents against emerging AD This test was designed to test immunogenic agents for activity in stopping or reversing the neuropathological characteristics of AD in aged mice. Immunizations with A 42 amino acids (AN1792) were initiated at a time point at which amyloid plaques were already present in the brains of PDAPP mice. Over time in the study, untreated PDAPP mice developed many AD-like neurodegenerative changes (Games et al., supra, and Johnson-Wood et al., Proc. Natl. Acad. Sci. USA 94, 1550-1555 (1997)). The deposition of Aß in amyloid plaques is associated with a degenerative neuronal response, including inappropriate axonal and dendritic elements, called dystrophic neurites. Amyloid logs surrounded by and containing dystrophic neurites are called neuritic plaques. In both AD and PDAPP mice, dystrophic neurites have distinctive globular structures, are immunoreactive with a set of antibodies recognizing APP and cytoskeletal components, and exhibit complex intracellular degenerative changes at the level of ultrastructural. These characteristics allow for disease-relevant, selective and repeatable measurements of neuritic plaque formation in PDAPP brains. The dystrophic neuronal component of PDAPP neuritic plaques is easily visualized using antibodies specific for human APP (mA ß 8E5) and is easily measured by computer-aided image analysis. Therefore, in addition to measuring the effect of AN1792 on the formation of amyloid plaques, the impact of this treatment on the development of neuritic dystrophy was monitored. Astrocytes and microglia are non-neuronal cells that respond to and reflect the degree of neuronal damage. GFAP-positive astrocytes and MHC II-positive microglia are frequently observed in AD, and their activation increases with disease severity. Therefore, the development of reactive astrocytes and microgliosis in AN1792-treated mice was monitored. AND. Materials and methods Forty-eight heterozygous female PDAPP mice, 11 to 11.5 months of age, obtained from Charles River, were randomly divided into two groups: 24 mice were immunized with 100 μg of AN1792 and 24 were immunized with PBS, in each case combination with Freund's adjuvant. The AN1792 and PBS groups were divided again at approximately 15 months of age. At 15 months of age, approximately half of each of the AN1792 and PBS groups were sacrificed (n=10 and 9, respectively), and the remainder continued to receive immunizations until the end at approximately 18 months of age. ecy (n=9 and 12, respectively). PL 203 431 B1 20 During the study, 8 animals died (5 AN1792, 3 PBS). In addition to the immunized animals, untreated PDAPP mice aged 1 year (n=10), 15 months (n=10) and 18 months (n=10) were included in the experiment for comparison in ELISA measurements of α- and APP in brains; additionally, one-year-old animals were included for immunohistochemical analysis. The methodology was as in Example 1, except where otherwise indicated. AN1792 from US Peptides series 12 and California Peptides series ME0339 were used to prepare the antigen for 6 immunizations administered 15 months ago. California Peptides series ME0339 and ME0439 were used for 3 additional immunizations administered between 15 and 18 months. For immunization, 100 μg of AN1792 was emulsified in 200 μl of PBS, or PBS alone, in a 1:1 ratio with complete Freund's adjuvant (CFA) or incomplete Freund's adjuvant (IFA) or PBS in a final volume of 400 μl. The first immunization was performed with CFA as an adjuvant, the next 4 doses were administered with IFA, and the final 4 doses were administered with PBS alone without the addition of adjuvant. A total of 9 immunizations were performed over a 7-month period, with two-week breaks for the first three doses and then four-week breaks for the remaining doses. In the group treated for 4 months, who died at the age of 15 months, only the first 6 immunizations were administered. B Results Effect of AN1792 treatment on amyloid load The results of AN1792 treatment on cortical amyloid load determined by quantitative image analysis are shown in Fig. 7. The median value for cortical amyloid load was 0.28% in the group of untreated 12-month-old PDAPP mice, which corresponded to the plaque burden in the mice at the beginning of the study. At 18 months of age, amyloid burden increased more than 17-fold to 4.87% in PBS-treated mice, while AN1792-treated mice had a significantly reduced amyloid burden of 0.01%, significantly less than at 12 months of age. month-old untreated mice and 15- and 18-month-old groups treated with PBS. Amyloid burden was significantly reduced in AN1792 recipients at both months 15 (96% reduction, p=0.003) and 18 (99% reduction, p=0.0002). Typically, amyloid logs in the cortex of PDAPP mice began in the frontal and retrocallosal cortex (RSC), progressed ventrolaterally, and involved the temporal and retrocalcortex (EC). Little or no amyloid was found in the EC of 12-month-old mice, i.e. at the age around which the first dose of AN1792 was administered. After 4 months of treatment with AN1792, amyloid logs significantly decreased in RSC, and the progressive proportion of EC was completely eliminated by AN1792 treatment. The latest observation showed that AN1792 completely stopped the progression of amyloid, which would normally attack the temporal cortex and echo chamber, and also stopped and possibly reversed the deposition in the RSC. A significant effect of AN1792 treatment on the development of cortical amyloid burden in PDAPP mice was shown for the 18-month-old group that was treated for 7 months. There was an almost complete absence of amyloid in the cortex in AN1792-treated mice, with a complete absence of scattered plaques and a reduction in solid plaques. 2. Cellular and morphological changes accompany AN1792 treatment. This population of Aβ-positive cells has been found in regions of the brain that typically contain amyloid logs. It was significant that very few or no cortical amyloid plaques were found in several AN1792 recipient brains. Most of the Aβ immunoreactivity turned out to be associated with cells with large, lobulated or adhesive bodies. Phenotypically, these cells resemble activated microglia or monocytes. They were immunoreactive with antibodies recognizing ligands expressed by activated monocytes and microglia (MHC II and CD11b), and sometimes they were bound to the walls or lumen of blood vessels. Comparison of closely adjacent fragments labeled with antibodies specific for Aβ and MHC II revealed that similar patterns of these cells were recognized by both classes of antibodies. Detailed examination of the brains of AN1792-treated mice revealed that MHC II-positive cells were confined to the vicinity of the limited amyloid remaining in these animals. Under the fixation conditions used, the cells were not immunoreactive with antibodies recognizing T cell ligands (CD3, CD3e) or B cells (CD45RA, CD45RB) or common leukocyte antigen (CD45), but were reactive with antibodies recognizing leukosialin e (CD43), which cross-reacts with monocytes. No such cells were found in any of the mice treated with PBS. PDAPP mice consistently developed severe amyloid logs in the outer molecular layer of the hippocampal gyrus embassy. The logs formed a distinct streak within the perforation zone, a region typically containing amyloid plaques in AD. The characteristic occurrence of these logs in PBS-treated mice was reminiscent of those previously characterized in untreated PDAPP mice. Amyloid logs consisted of both dispersed and solid plaques in a continuous band. However, in many AN1792-treated mouse brains, this pattern was significantly altered. The amyloid logs in the hippocampus did not contain any scattered amyloid and the banding pattern was partially destroyed. Instead, there were many unusual speckled structures reacting with anti-Aß antibodies, several of which turned out to be amyloid-containing cells. MHC II-positive cells were often observed in the vicinity of extracellular amyloid in AN1792-treated animals. The pattern of Aβ-positive amyloid binding was very similar in several AN1792-treated mouse brains. The distribution of these monocyte cells was limited to the neighborhood of amyloid logs and was completely absent in other brain regions lacking Aβ plaques. Quantitative image analysis of MHC II and MAC I labeled fragments showed a trend towards increased reactivity in the RSC and hippocampus in AN1792-treated mice, compared to the PBS group, which reached a significant value for reactivity measurements. MAC 1 in the hippocampus. These results indicate active, cell-directed amyloid removal in brain regions where plaques occur. 3. Effect of AN1792 on Aß levels: ELISA assays. (a) Cortical levels In untreated PDAPP mice, the median total cortical Aβ level was 1600 ng/g at 12 months of age, increasing to 8700 ng/g at 15 months of age (Table 2). At the age of 18 months, the value is 22,000 ng/g, which means that it increased more than 10 times during the experience. Animals treated with PBS had 8,600 ng/g of total Aß at 15 months of age, which increased to 19,000 ng/g at 18 months of age. In comparison, AN1792-treated animals had 81% less total Aβ at 15 months of age (1600 ng/g) than the PBS-immunized group. Significantly less (0=0.0001) total Aß (5200 ng/g) was found at 18 months when comparing the AN1792 and PBS groups (Table 2), corresponding to a 72% reduction in the amount of Aß that would normally be performed. Similar results were obtained when comparing cortical A ß42 levels, as it was found that the AN1792-treated group contained significantly less A ß42, but in this case the differences between the AN1792 and PBS groups were significant in both (p=0.04 ), as well as 18 months acu (p=0.0001, table 2). T able 2 Median A ß Levels (ng/g) in Cortex Untreated PBS AN1792 Age Total A ß Aß42 (n) Total A ß Aß42 (n) Total A ß A ß42 (n) 12 1600 1300 (10) 15 8700 8300 (10) 8600 7200 (9) 1600 1300* (10) 18 22200 18500 (10) 19000 15900 (12) 5200** 4000** (9) *p = 0.0412 **p = 0.0001 ( b) Hippocampal levels In untreated PDAPP mice, the median hippocampal levels of total Aβ at 12 months of age were 15,000 ng/g, which increased to 51,000 ng/g at 15 months of age and continued to increase agaj ac 81,000 ng/g at 18 months of age (Table 3). Similarly, mice immunized with PBS had 40,000 ng/g and 65,000 ng/g at 15 and 18 months of age, respectively. In animals treated with AN1792, a lower total amount of SC Aß was found, i.e. 25,000 ng/g and 51,000 ng/g at the age of 15 and 18 months, respectively. The value for the AN1792-treated group at 18 months of age was significantly lower than that for the PBS-treated group (p=0.0105; Table 3). A ß42 measurements gave the same pattern of results, that is, the levels in the AN1792-treated group were significantly lower than those in the PBS-treated group (39,000 ng/g vs. 57,000 ng/g, respectively; p=0.0022) in age 18 months (Table 3). PL 203 431 B1 22 T able 3 Median A ß levels (ng/g) in hippocampus Untreated PBS AN1792 Age Total A ß A ß42 (n) Total A ß Aß42 (n) Total A ß A ß42 (n) 12 15500 11100 (10) 15 51500 44400 (10) 40100 35700 (9) 24500 22100 (10) 18 80800 64200 (10) 65400 57100 (12) 50900* 38900** (9) *p = 0, 0105 **p = 0.0022 (c) Cerebral levels In 12-month-old untreated PDAPP mice, the median total Aβ level was 15 ng/g (Table 4). At the age of 15 months, this median increased to 28 ng/g, and at the age of 18 months to 35 ng/g. In animals treated with PBS, the median value of total Aβ was 21 ng/g at 15 months of age and 43 ng/g at 18 months of age. In AN1792-treated animals, 22 ng/g of total Aß at 15 months of age and significantly less (p=0.002) total Aß at 18 months of age (25 ng/g) were found than in the corresponding group. im the PBS group (Table 4). T able 4 Mean Cerebral A ß Levels (ng/g) Untreated PBS AN1792 Age (months) Total A ß (n) Total A ß (n) Total A ß (n) 12 15.6 ( 10) 15 27.7 (10) 20.8 (9) 21.7 (10) 18 35.0 (10) 43.1 (12) 24.8* (9) *p=0.0018 4. Effect of AN1792 treatment on APP levels APP-a and the full-length APP molecule contain all or part of the Aß sequence and therefore could potentially be influenced by the production of an immune response driven by AN1792. Previous studies have found a slight increase in APP levels with increasing neuropathology in PDAPP mice. In the cortex, levels of both APP-α/FL (full length) and APP-α remained essentially unchanged during treatment, except that APP-α levels were reduced by 19% in mice aged 18 months in the group treated with AN1792 compared to the group treated with PBS. APP values in 18-month-old animals from the AN1792 group did not differ significantly from those for 12- and 15-month-old untreated animals and 15-month-old animals treated with PBS. In all cases, APP values remained within the range normally found in PDAPP mice. 5. Effect of AN1792 treatment on neurodegenerative and glial pathology. Neuritic plaque burden was significantly reduced in the frontal cortex of AN1792-treated mice compared to the PBS-treated group at both 15 (84%; p=0.03) and 18 months of age (55 %; p=0.01) (fig. 8). The median neuritic plaque burden increased from 0.32% to 0.49% in the PBS group between 15 and 18 months of life. In contrast, the development of neuritic plaques in the AN1792-treated group was significantly reduced, with median neuritic plaque burden values of 0.05% and 0.22% at 15 and 18 months of age, respectively. AN1792 immunizations appeared to be well tolerated, and reactive astrocytosis decreased significantly in RSCs in AN1792-treated mice compared to the PBS-treated group at both ages 15 (56%; p=0.011) and 18 months (39%; p=0.028) (fig. 9). The median percentage of astrocytosis in the PBS group increased between 15 and 18 months from 4.26% to 5.21%. AN1792 treatment reduced the development of astrocytosis at both time points to 1.89% and 3.2%, respectively. This suggests that neuropil was not destroyed by the clearance process. PL 203 431 B1 23 6. Antibody responses l As described above, 11-month-old heterozygous PDAPP mice (n=24) received a series of 5 immunizations with 100 μg AN1792 emulsified with Freund's adjuvant, administered intraperitoneally at weeks 0, 2, 4, 8 and 12, and the sixth immunization was performed with PBS alone (without Freund's adjuvant) at week 16. As negative controls, a set of age-matched 24 mice was prepared, which were immunized with PBS emulsified with the same adjuvants and administered on the same schedule. Blood was collected from the animals 3-7 days after each immunization, starting with the second dose. Antibody responses to AN1792 were measured by ELISA. Geometric mean titers (GMT) for animals immunized with AN1792 were approximately 1900, 7600 and 45000 after the second, third and last (sixth) doses, respectively. After the sixth immunization, no Aβ-specific antibodies were found in control animals. About half of the animals were treated for another 3 months, immunizing them at approximately 20, 24 and 27 weeks. Each dose was administered in a medium of PBS alone, without Freund's adjuvant. The mean antibody titers did not change during this time. In fact, antibody titers remained stable in the period from the fourth to the eighth blood collection, corresponding to the period from the fifth to the ninth injection. To determine whether Aβ-specific antibodies generated by immunization were detected in the serum of AN1792-treated mice such that they were associated with amyloid deposited in the brain, a panel of histological preparations from mice treated with AN1792 and PBS were treated with antibodies specific for mouse IgG. Unlike the PBS group, Aβ plaques in the brains of AN1792-treated mice were coated with endogenous IgG. These differences between both groups were observed for both 15- and 18-month-old mice. Particularly striking was the lack of labeling in the PBS group, despite the presence of a high amyloid burden in these mice. These results show that immunization with synthetic Aβ protein produces antibodies that recognize and bind to Aβ in amyloid plaques in vivo. 7. Cellular immune responses Spleens were collected from nine AN1792-immunized mice and 12 PBS-immunized PDAPP mice at 18 months of age 7 days after the ninth immunization. Spleen lymphocytes were isolated and cultured for 72 hours in the presence of A ß40, A ß42 or A ß40-1 (reverse sequence protein). Mitogen Con A served as a positive control. Optimal responses were obtained using 1.7 µM protein. Cells from all nine AN1792-treated mice proliferated in response to A ß1-40 or A ß1-42 proteins, with equal levels of incorporation of both proteins (Fig. 10, top graph). There was no response to the protein with the reverse sequence A ß40-1. Cells from control animals did not respond to any of the Aβ proteins (Fig. 10, lower graph). C Conclusions The results of this study demonstrated that immunization with AN1792 of PDAPP mice bearing amyloid logs slows and prevents progressive amyloid deposition and inhibits the consequent neuropathological changes in the brains of aged PDAPP mice. AN1792 immunizations significantly inhibit the development of amyloid in structures that are normally subject to amyloidosis. Therefore, administration of Aβ-peptide has a positive effect in the treatment of AD. VI. Screening for Aβ fragments 100 9-11 month old PDAPP mice were immunized with nine different regions of APP and Aβ to determine which epitopes were involved in the response. Nine different immunogens and one control were administered i. Mr. , as described above. Immunogens contain 4 conjugates of human A peptides ß 1-12, 13-28, 32-42, 1-5, all linked via a cysteine link to sheep anti-mouse IgG antibodies, APP polypeptide amino acids 592-695, aggregated human A ß1-40, aggregated human A ß25-35 and aggregated A ß42 from rodents. Aggregated Aβ42 and PBS were used as controls. There were 10 mice for each treatment group. Titers were monitored as above, and mice were sacrificed at the end of 4 months of immunization. After death, histochemistry, Aß levels and toxicology were determined. AND. Materials and methods 1. Preparation of immunogens Preparation of conjugated A ß peptides: 4 human A ß peptide conjugates (amino acids 1-5, 1-12, 13-28 and 33-42, each linked to sheep anti-mouse IgG antibodies) were prepared by cysteine coupling that artificially added to the Aβ peptide using sulfo-EMCS cross-linking agent. Aβ peptide derivatives were synthesized with the following terminal amino acid sequences. In each case, the location of the inserted cysteine is indicated by underlining. PL 203 431 B1 24 The β13-28 peptide A derivative also had, as indicated, two glycines added before the C-terminal cysteines of α. peptide A ß1-12 NH 2 -DAEFRHDSGYEVC COOH peptide A ß1-5 NH 2 -DAEFRC COOH peptide A ß33-42 NH 2 -C-aminoheptanoic acid-GLMVGGVVIA COOH peptide A ß13-28 Ac-NH-HHQKLVFFAEDVGSNKGGC-COOH For preparation for the conjugation reaction, 10 mg of sheep anti-mouse IgG (Jackson ImmunoResearch Laboratories) was dialyzed overnight against 10 mM sodium borate buffer, pH 8.5. The separated antibodies were then concentrated to a volume of 2 ml using an Amicon Centriprep tube. Ten mg of sulfo-EMCS [N(e-maleimidocuproyloxy)-succinimide] (Molecular Sciences Co. ) was dissolved in 1 ml of deionized water. A 40-fold molecular excess of sulfo-EMCS was added dropwise to the sheep anti-mouse IgG antibody with stirring, and the solution was then stirred for another 10 minutes. Activated sheep anti-mouse IgG antibodies were purified and buffer exchanged by passing through a 10 ml gel filtration column (Pierce Presto Column, obtained from Pierce Chemicals) equilibrated with 0.1 M NaPO4, 5 mM EDTA, pH 6, 5. Fractions containing antibodies, identified by measuring absorbance at 280 nm, were pooled and diluted to a concentration of approximately 1 mg/ml, using 1.4 mg per OD as the extinction coefficient. A forty-fold molecular excess of A ß peptide was dissolved in 20 ml of 10 mM NaPO 4, pH 8.0, except for A ß peptide33-42, 10 mg of which was first dissolved in 0.5 ml of DMSO and then diluted to 20 ml 10 mM NaPO 4 buffer. Each peptide solution was added to 10 ml of activated sheep anti-mouse IgG and rocked at room temperature for 4 hours. The resulting conjugates were concentrated to a final volume of less than 10 ml using an Amicon Centriprep tube and then dialyzed against PBS buffer to replace the buffer and remove free peptides. The conjugates were passed through 0.22 µ filters for sterilization and then divided into equal 1 mg fractions and stored frozen at -20°C. Conjugate concentrations were determined using the BSA protein assay (Pierce Chemicals) with horse IgG as a standard curve. The conjugation was confirmed by an increase in the molecular weight of the conjugated peptides compared to activated anti-mouse IgG antibodies. The A ß1-5 sheep anti-mouse IgG conjugate preparation contains 1 combined conjugates from two conjugation reactions, the rest is a single preparation. 2. Preparation of Aggregated Peptides A ß Peptides Human 1-40 (AN1528; California Peptides Inc. , series ME0541), human 1-42 (AN1792; California Peptides Inc. , lots ME0339 and ME0439), human 25-35 and rodent 1-42 (California Peptides Inc. , batch ME0218) were freshly solubilized for the preparation of each set of injections from freeze-dried powders that were stored dried at -20°C. For this purpose, 2 mg of peptide was added to 0.9 ml of deionized water and the mixtures were vortexed to produce a relatively homogeneous solution or suspension. Of the four peptides, the only one soluble at this stage was 1 AN1528. Equal volumes of 100 µl of 10x PBS (1x PBS: 0.15 NaCl, 0.01 M sodium phosphate, pH 7.5) were then added and then AN1528 started to precipitate. The suspension was vortexed again and incubated overnight at 37°C until used the next day. Preparation of pBx6 protein: The expression plasmid encoding pBx6, a fusion protein consisting of the 100 amino acid N-terminal leader sequence from bacteriophage MS-2 polymerase and amino acids 592-695 of APP (ßAPP), was constructed as described in Oltersdorf et al., J. Biol. Chem. 265, 4492-4497 (1990). The plasmid was transfected into E. coli and the protein was expressed after promoter induction. The bacteria were lysed in 8M urea and pBx6 was partially purified by preparative SDS PAGE. Fractions containing pBx6 were identified by Western blotting using rabbit polyclonal antibodies against pBx6, collected, concentrated using an Amicon Centriprep tube, and dialyzed against PBS. The purity of the preparation, determined by staining Coomassie Blue SDS PAGE, is approximately 5 to 10%. B Results and their discussion 1. Design studies n One hundred female and male, 9- to 11-month-old heterozygous transgenic PDAPP mice were obtained from the Charles River Laboratory and the Taconic Laboratory. Mice were divided into 10 groups for immunization with different regions of Aβ or APP together with Freund's adjuvant. The animals were divided by gender, age, parents and source within the group as closely as possible. The immunogens included 4 human sequence-derived Aβ peptides, 1-5, 1-12, 13-28, and 33-42, each conjugated to a sheep anti-mouse IgG antibody; 4 aggregated Aβ peptides, human 1-40 (AN1528), human 1-42 (AN1792), human 25-35 and rodent 1-42; and a fusion polypeptide called pBx6, containing APP amino acids 592-695. Ten groups were immunized with PBS in combination with adjuvant as a control. For each immunization, 100 μg of each Aβ peptide was emulsified in 200 μl of PBS or 200 μg of the APP derivative pBx6 in the same volume of PBS, or with PBS alone in a 1:1 ratio (vol. ) with complete Freund's adjuvant (CFA) in a final volume of 400 µl for the first immunization, followed by booster doses with the same amount of immunogen in incomplete Freund's adjuvant (IFA) in the next four doses and PBS for new dose. Immunization was administered intraperitoneally on a biweekly basis for the first 3 doses, and then on a monthly basis. Blood was collected from the animals 4-7 days after each immunization, starting with the second dose, for antibody titer measurements. The animals were sacrificed approximately one week after the final dose. 2. Aβ and APP levels in the brain After 4 months of immunization with different Aβ peptides or an APP derivative, the brains were removed from the saline-perfused animals. One half of the hemisphere was prepared for immunohistochemical analysis, and the other one was used to determine the levels of Aβ and APP. To measure the concentration of different forms of β-amyloid peptide and amyloid precursor protein, hemispheres were cut into pieces and homogenates of the hippocampus, cortex, and cerebral regions were prepared in 5 M guanidine. They were diluted and the level of amyloid or APP was determined by comparing them to a series of dilutions of Aβ-peptide or APP standards with known concentrations in the ELISA format. The mean concentration of total Aβ for PBS-immunized controls was 5.8-fold higher in the hippocampus than in the cortex (median 24,318 ng/g hippocampal tissue compared to 4,221 ng/g cortex). The median level in the brain of the control group (23.4 ng/g tissue) was approximately 1000 times lower than in the hippocampus. These levels were similar to those previously described for PDAPP heterozygous transgenic mice of this age (Johnson-Woods et al., 1997, supra). For cortex, treatment group sets had mean total levels of Aß and Aß1-42 that were significantly different from the control group (p <0.05), animals receiving AN1792 peptides, rodent A ß1-42, or the A ß1-5 conjugate are shown in Figure 11. Median total A ß levels decreased by 75%, 79%, and 79%, respectively. 61% compared to controls for these treatment groups. There were no discernible correlations between Aß-specific antibody titers and Aß levels in the cortical region of the brain for any of these groups. In the hippocampus, the mean reduction in total Aß with AN1792 treatment (46%, p=0.0543) was not as great as that observed in the cortex (75%, p=0.0021). However, since the rate of n reduction was much higher in the hippocampus than z in the cortex, the net reduction was 11,186 ng/g tissue in the hippocampus versus 3,171 ng/g tissue in the cortex. For groups of animals receiving Aß1-42 from rodents or Aß1-5, the mean total Aß levels decreased by 36% and 26%, respectively. However, given the fact that the groups were small and due to the variability of amyloid peptide levels among individual animals within the group, these changes were not significant. When measuring Aß1-42 in the hippocampus, none of the changes induced by treatment were significant. Therefore, due to the lower Aß load on the cortex, changes in this region are a much more sensitive indicator of the effects of treatment. Changes in Aβ levels measured by ELISA in the cortex were similar, but not the same, to the results of the immunohistochemical analysis (see below). Total Aß was also measured in the cerebrum, a region not usually affected in AD pathology. None of the mean Aβ concentrations of any of the groups immunized with the different Aβ peptides or the APP derivative differed from those of the control group in this brain region. This result suggests that treatment does not affect non-pathological Aß levels. The concentration of APP was also determined by ELISA in the cortex and cerebrum of treated and control animals. Two different APP tests were used. The first, called APP-a/FL, recognizes both APP-a (a, the secreted form of APP that has been taken within the A ß sequence) and the full-length form of APP (FL), while while the other recognizes only APP-α. In contrast to the treatment-accompanied reduction in Aβ in the treatment group, APP levels remained unchanged in all treated animals compared to controls. These results indicate that immunization with Aβ peptides does not remove APP and that the therapeutic effect is rather specific for Aβ. In summary, total Aβ and Aβ1-42 levels were significantly reduced in the cortex by treatment with AN1792, rodent Aβ1-42, or Aβ1-5 conjugate. In the hippocampus, total Aß was significantly reduced only by AN1792 treatment. No other treatment-related changes in Aβ or APP levels in the hippocampal, cortical, or cerebral regions were significant. 2. Histochemical analysis Brains from a subset of six groups were prepared for immunohistochemical analysis, 3 groups immunized with A ß peptide conjugates - A ß1-5, A ß1-12 and A ß13-28; 3 groups immunized with full-length Aβ aggregates - AN1792 and AN1528 and a control group treated with PBS. The results of image analysis for the amyloid load of brain histological sections from these groups are shown in Fig. 12. A significant reduction in the amyloid load of cortical regions was found in the 3 treatment groups compared to control animals. The greatest reduction in amyloid load was observed in the groups receiving AN1792, where the mean value was reduced by 97% (p=0.001). A significant reduction was also observed for animals treated with AN1528 (95%, p=0.005) and the A ß1-5 peptide conjugate (67%, p=0.02). The results obtained by measuring total Aβ or Aβ1-42 by ELISA and amyloid load by image analysis differ to some extent. AN1528 treatment had a significant effect on the level of cortical amyloid load measured by quantitative image analysis, but had no effect on the concentration of total Aß measured by ELISA in the same region. The difference between these two results is probably related to the specificity of the tests. Image analysis only measures insoluble Aß aggregated in the plates. In contrast, ELISA measures all forms of Aß, both soluble and insoluble, monomeric and aggregated. Since the pathology of the disease is believed to be related to the insoluble form of Aß bound to platelets, the image analysis technique may have greater sensitivity in assessing the effects of treatment. However, because ELISA is a faster and easier test, it is very useful in the search for new drugs. Furthermore, this may mean that the treatment-related reduction in Aß is greater for platelet-bound than for total Aß. To determine whether Aβ-specific antibodies generated by immunization in treated animals reacted with brain amyloid deposits, a subset of histological sections from treated and control animals were exposed to antibodies specific for murine IgG. Unlike the PBS group, plates containing Aβ were coated with endogenous IgG in animals immunized with Aβ-Aβ1-5, Aβ1-12 and Aβ13-28 peptide conjugates; and full-length A ß units - AN1792 and AN1528. The brains of animals immunized with other Aβ peptides or the APP pBx6 peptide were not analyzed in this assay. 3. Measurement of antibody titers l Blood was collected from mice 4-7 days after each immunization, starting with the second immunization, for a total of 5 times. Antibody titers binding to A ß1-42 were measured using the sandwich ELISA method on plastic multiwell plates coated with A ß1-42. As shown in Figure 13, peak antibody titers were produced after the fourth dose for those 4 vaccines that induced the highest AN1792-specific antibody titers: AN1792 (peak GMT: 94647), AN1528 (peak GMT: 88231), conjugate A ß1-12 (peak GMT 47216) and rodent A ß1-42 (peak GMT: 10766). Titers for these groups decreased to some extent after the fifth and sixth doses. For the remaining five immunogens, peak titers reached after the fifth and sixth doses and were much lower than those obtained for the four groups of the highest titers: conjugate A ß1-5 (peak GMT: 2356), pBx6 (peak GMT: 1986), conjugate A ß13-28 (peak GMT: 1183), conjugate A ß33-42 (peak GMT: 658), A ß25-35 (peak GMT: 125). Antibody titers were also measured against homologous peptides using the same sandwich ELISA format for a subset of immunogens, immunized groups A ß1-5, A ß13-28, A ß25-35, A ß33-42 and rodent A ß1- 42. These titers were approximately the same as those measured against A ß1-42, with the exception of rodent immunogen A ß1-42, for which antibody titers against the homologous immunogen were approximately 2-fold higher. The amount of AN1792-specific antibody titer in individual animals or the average value for treatment groups was unrelated to the effectiveness measured as a reduction in Aß in the cortex. 4. Lymphoproliferative responses Aβ-dependent lymphoproliferation was measured using spleen cells collected approximately one week after the final sixth immunization. Freshly harvested cells, 10 5 per well, were cultured for 5 days in the presence of A ß1-40 at a concentration of 5 μM for stimulation. Cells from a subset of seven of the ten groups were cultured in the presence of the reverse sequence A peptide β40-1. As a positive control, additional cells were cultured with the T cell mitogen, PHA, and as a negative control, cells were cultured without the added peptide. Lymphocytes from most animals proliferated in response to PHA. No significant responses were found to the reverse sequence A peptide ß40-1. Cells from animals immunized with higher aggregated A ß peptides, AN1792, rodent A ß1-42 and AN1528, proliferated strongly after stimulation with A ß1-40 with the highest cmp in AN1792 recipients. In one of the animals in each group immunized with A ß1-12, A ß13-28 and A ß25-35 conjugates, cells proliferated in response to A ß1-40. In the remaining groups receiving conjugates A ß1-5, A ß33-42 and pBx6 or PBS, there were no animals responding and stimulated with A ß. These results are summarized in table 5 below. T able 5 Immunogen Conjugate Amino acids Aß Animals corresponding to ace Aß1-5 yes 5-mer 0/7 Aß1-12 yes 12-mer 1/8 Aß13-28 yes 16-mer 1/9 Aß25-35 11-mer 1/ 9 Aß33-42 yes 10-mer 0/10 Aß1-40 40-mer 5/8 Aß1-42 42-mer 9/9 rodent A ß1-42 42-mer 8/8 pBx6 0/9 PBS 0-mer 0/ 8 These results indicate that AN1792 and AN1528 most strongly stimulate T cell responses, most likely with the CD4 + phenotype. The lack of an Aβ-specific T cell response in animals immunized with Aβ1-5 is not surprising since the peptide epitopes recognized by CD4 + T cells are usually 15 amino acids long, although shorter peptides may sometimes act c with lower effectiveness. Therefore, most of the helper T cell epitopes for the four peptide conjugates are located in the IgG portion of the conjugate and not in the Aβ region. This hypothesis is supported by the very low frequency of proliferative responses for animals from each of these treatment groups. Because the Aβ1-5 conjugate was effective in significantly reducing Aβ levels in the brain, in the apparent absence of Aβ-specific T cells, a key effector immune response triggered by immunization with this the peptide turns out to be an antibody. The lack of T cells and the low antibody response to the pBx6 fusion protein, containing APP amino acids 592-695 including all A ß amino acids, may be due to the poor immunogenicity of a particular preparation. The poor immunogenicity of A ß25-35 aggregate is likely due to the peptide being too small to be likely to contain a good T cell epitope to aid in the induction of an antibody response. If this peptide were conjugated to a carrier protein would probably be more immunogenic. V. Preparation of polyclonal antibodies for passive protection. 20 non-transgenic mice immunized with Aβ or other immunogen, additionally with adjuvant, were sacrificed at the age of 4-5 months. Blood from immunized mice was collected. Alternatively, IgG has been isolated from other blood components. Immunogen-specific antibodies were partially purified by affinity chromatography. An average of 0.5-1 mg of immunogen-specific antibodies was obtained per mouse, for a total of 5-10 mg. VI. Passive immunization with antibodies to Aβ Groups of 7-9 month old PDAPP mice were administered 0.5 mg in PBS of polyclonal anti-Aβ antibodies or specific monoclonal anti-Aβ antibodies, as shown below. Monoclonal antibodies can be prepared against the fragment by injecting mice with the fragment or a longer form of Aβ, preparing hybridomas, and screening the hybridomas for an antibody that specifically binds the required Aβ fragment without binding other effects. fragments of A ß.PL 203 431 B1 28 T able 6 Epitope antibody 2H3 A ß1-12 10D5 A ß1-12 266 A ß13-28 21F12 A ß33-42 Mouse polyclonal antihuman A ß42 against aggregated A ß42 was administered to animals by 4 months of intraperitoneal preparations, as this was needed to maintain antibodies in circulation at concentrations, measured as ELISA titers, greater than 1/1000, determined by ELISA against A ß42 or another immunogen. Titers were monitored as above and the mice were sacrificed at the end of 4 months of injections. After death, histochemistry, determination of Aβ levels and toxicology were performed. 10 mice were used in each group. VII. Comparison of Different Adjuvants These examples compare CFA, Lun, Oil-in-Water Emulsions and MPL in terms of their ability to stimulate an immune response. A. Materials and methods 1. Study design One hundred six-week-old female Hartley guinea pigs obtained from Elm Hill were divided into 10 groups for immunization with AN1792 or its palmitoylated derivative, combined with various adjuvants. Seven groups were immunized by injection of AN1792 (33 μg, unless otherwise stated) combined with a) PBS, b) Freund's adjuvant, c) MPL, d) squalene, e) MPL/squalene, f) low a dose a with a Lun or g) a high dose a with a Lun (300 µg AN1792). Two groups were immunized by injection of a palmitolated derivative of AN1792 (33 μg) combined with a) PBS or b) squalene. Finally, the tenth group received PBS alone, without antigen and additional adjuvant. For the group receiving Freund's adjuvant, the first dose was emulsified with CFA and the remaining 4 doses with IFA. The antigen was administered at a dose of 33 μg to all 11 groups, except the high-dose alum group, which received 300 μg of AN1792. Immunizations were performed intraperitoneally for CFA/IFA and intramuscularly into the quadriceps muscle of the hind limb, alternating on the right and left sides for all other groups. The first three doses were administered on a two-week schedule, followed by two doses one month apart. Blood was collected 6-7 days after each immunization, starting with the second dose, to measure antibody titer I. 2. Preparation immunogens Two mg of A ß42 (California Peptide, lot ME0339) were added to 0.9 ml of deionized water and the mixture was vortexed to form a relatively homogeneous suspension. 100 µl of 10x PBS (1x PBS, 0.15 M) was added NaCl, 0.01 M sodium phosphate, pH 7.5). The suspension was vortexed again and incubated overnight at 37°C until used the next day. Unused Aß1-42 was stored with a desiccant as a lyophilized powder at -20°C. The palmitoylated derivative of AN1792 was obtained by coupling palmitic anhydride, suspended in dimethylformamide, with the N-terminal amino acid of AN1792, before removing the resulting peptide from the resin by treatment with hydrofluoric acid. To prepare vaccine doses with complete Freund's adjuvant (CFA) (group 2), 33 µg of AN1792 was emulsified in 200 µl of PBS in a 1:1 (v/v) ratio with CFA in a final volume of 400 µl for the first immunization. For subsequent immunizations, the antigen was similarly emulsified with incomplete Freund's adjuvant (IFA). To prepare the MPL vaccine doses for groups 5 and 8, lyophilized powder (Ribi ImmunoChem Research, Inc., Hamilton, MT) was added to 0.2% aqueous triethylamine solution to a final concentration of 1 mg/ml and the entire sc was vortexed. The mixture was heated to 65 to 70°C for 30 seconds to produce a slightly opaque and homogeneous micelle suspension. The solution was freshly prepared for each set of injections. For each injection in group 5, 33 µg of AN1792 in 16.5 µl of PBS, 50 µg of MPL (50 µl), and 162 µl of PBS were mixed in a borosilicate tube immediately before use. To prepare vaccine doses from a small amount of oil-in-water emulsion, AN1792 in PBS was added to 5% squalene, 0.5% Tween 80, 0.5% Span 85 in PBS to the final concentration in a single -PL 203 431 B1 29 dose of 33 µg AN1792 in 250 µl (group 6). The mixture was emulsified by passing it through a two-chamber hand-held device 15 to 20 times until emulsion droplets were obtained with a diameter similar to that of a standard 1 µm latex bead when analyzed microscopically. the obtained suspension was opalescent, milky white. Fresh soil emulsions were prepared for each series of injections. For group 8, MPL in 0.2% triethylamine was added at a concentration of 50 Pg per dose to the squalene-detergent mixture for emulsification as described above. For the palmitoyl-NH-A derivative (group 7), 33 µg per dose of palmitoyl-NH-A ß1-42 was added to squalene and vortexed. Tween 80 and Span 85 were then added and vortexed. The mixtures were added to PBS to reach final concentrations of 5% squalene, 0.5% Tween 80, 0.5% Span 85 and the mixtures were emulsified as above. To prepare doses of alum vaccines (groups 9 and 10), AN1792 in PBS was added to Alhydrogel (aluminum hydroxide gel, Accurate, Wetsbury, NY) to reach a concentration of 33 μg (low dose, group 9) or 300 µg (high dose, group 10) AN1792 per 5 mg of lunu, in a final dose volume of 250 µl. The suspension was stirred gently for 4 hours at room temperature. 3. Measurements of antibody titers l Blood was collected from guinea pigs 6-7 days after immunization, starting after the second immunization, and this was done 4 times. Antibody titers against Aβ42 were measured by ELISA as described in the general materials and methods. 4. Tissue preparations After approximately 14 weeks, all guinea pigs were given CO 2. Cerebrospinal fluid was collected and the brains were removed, and three brain regions were dissected (hippocampus, cortex and cerebellum), which were used to measure total Aß concentration using the ELISA method. B. Results 1. Antibody Responses A wide range of effectiveness of the various adjuvants was observed as measured by antibody response assays to AN1792 following immunization. As shown in Figure 14, when AN1792 was administered in PBS, no antibody was detected after two or three immunizations, and small responses were detected after the fourth and fifth doses with a geometric mean titer (GMT) of only approximately 45. Oil-in-water emulsion produced moderate titers after the third dose (GMT 255), which were maintained after the fourth dose (GMT 301) and decreased after the final dose (GMT 54). There was a clear antigenic dose response for AN1792 bound to flax, with 300 Pg being more immunogenic at all time points than 33 Pg. At peak antibody response, after the fourth immunization, the difference between the two doses was 43% with a GMT of approximately 1940 (33 µg) and 3400 (300 µg). The antibody response to 33 µg of AN1792 plus MPL was very similar to that produced by an almost 10-fold higher dose of antigen (300 µg) associated with flax. The addition of MPL to the oil-in-water emulsion reduced the strength of the vaccine compared to the vaccine with MPL as the only adjuvant by as much as 75%. The palmitoylated derivative AN1792 was completely non-immunogenic when administered in PBS and gave average titers when administered in an oil-in-water emulsion with GMT of 340 and 105 for the third and fourth blood draws. The highest antibody titers were produced by Freund's adjuvant with a peak GMT of approximately 87,000, which was almost 30 times higher than the GMT of the next strongest vaccines, MPL and high dose AN1792/a lun. The most promising adjuvants identified in this study are MPL and alun. Of the two, MPL appears to be advantageous because a 10-fold lower dose of antigen was necessary to generate the same antibody response as that obtained with alun. The response can be enhanced by increasing the dose of antigen and/or adjuvant and optimizing the immunization regimen. The oil-in-water emulsion was a very weak adjuvant for AN1792, so the addition of the oil-in-water emulsion to the MPL adjuvant reduced the intrinsic activity of the MPL adjuvant itself. 2. Levels of Aß in the brain At approximately 14 weeks of age, guinea pigs were deeply anesthetized, cerebrospinal fluid (CSF) was collected, and the brains were removed from the animals in a subset of groups immunized with Freud's adjuvant (group 2), MPL (group 5). ), and from a high dose of 300 µg AN1792 (group 10) and from a control group immunized with PBS (group 3). To measure Aβ peptide levels, one hemisphere was dissected and homogenates of the hippocampus, cortex, and brain regions were prepared in 5 M guanidine. They were then diluted and determined by comparison with a series of dilutions of standard Aβ protein with known concentrations, in the ELISA format. Levels of Aß in the hippocampus, cortex, and cerebrum were very similar for all groups, despite the wide range of antibody responses to Aß induced by these vaccines. Mean tissue Aß levels were measured to be approximately lo 25 ng/g in the hippocampus, 21 ng/g in the cortex and 12 ng/g in the cerebrum. Therefore, the presence of high circulating titers of anti-Aß antibodies for almost 3 months in some of these animals did not change the overall levels of Aß in their brains. Aß levels in CFS were similar between groups. The lack of clear effects of AN1792 immunization on endogenous Aß indicates that the immune response is focused on pathological forms of Aß. VIII. Immune response to various adjuvants in mice Six-week-old female Swiss Webster mice were used for these studies with 10-13 animals per group. Immunizations were performed intraperitoneally on days 0, 14, 28, 60, 90 and 20, at doses with a volume of 200 µl. PBS was used as a buffer for all stimulations. Blood was collected from the animals 7 days after each immunization, starting after the second dose, for analysis of antibody titers in the ELISA test. The treatment regimen for each group is given in Table 7. T able 7 Experimental Design Betabloc 010 Group N a Adjuvant b Dose Antigen Dose (µg) 1 10 MPL 12.5 µg AN1792 33 2 10 MPL 25 µg AN1792 33 3 10 MPL 50 µg AN1792 33 4 13 MPL 125 µg AN1792 33 5 13 MPL 50 µg AN1792 150 6 13 MPL 50 µg AN1528 33 7 10 PBS AN1792 33 8 10 PBS - 9 10 emulsified squalene 5% AN1792 33 10 10 mixed squalene 5% AN1792 33 11 10 a lun 2 mg AN1792 33 12 13 MPL+a lun 50 µg/2 mg AN1792 33 13 10 QS21 5 µg AN1792 33 14 10 QS21 10 µg AN1792 33 15 10 QS21 25 µg AN1792 33 16 13 QS21 25 µg AN1792 150 17 13 QS21 25 µg AN1528 33 18 13 QS21+MPL 25 µg/ 50 µg AN1792 33 19 13 QS21+a lun 25 µg/ 2 mg AN1792 33 References: a Number of mice in each group at baseline b Adjuvant indicated you. PBS was used as a buffer for all preparations. Group 8 received no antigen or adjuvant. PL 203 431 B1 31 ELISA titers of anti-Aβ42 antibodies for each group are shown in Table 8 below. T able 8 Geometric means of antibody titers l Week n of blood collections Treatment group 2.9 5.0 8.7 12.9 16.7 1 248 1797 2577 6180 4177 2 598 3114 3984 5287 6878 3 1372 5000 7159 1233 3 12781 4 1278 20791 14368 20097 25631 5 3288 26242 13229 9315 23742 6 61 2536 2301 1442 4504 7 37 395 484 972 2149 8 25 25 25 25 25 9 25 183 74 4 952 1823 10 25 89 311 513 817 11 29 708 2618 2165 3666 12 198 1458 1079 612 797 13 38 433 566 1080 626 14 104 541 3247 1609 838 15 212 2630 2472 1224 1496 16 183 2616 6680 2085 1631 17 28 201 375 222 1540 18 31699 15544 23095 6412 9059 19 63 243 554 299 441 The table shows that the highest titres were obtained for groups 4, 5 and 18, in which the adjuvants were lo 125 µg MPL, 50 µg MPL and QS21 plus MPL. IX. Therapeutic efficacy of various adjuvants Therapeutic efficacy studies were conducted on PDAPP transgenic mice, with a set of adjuvants suitable for use in humans, to determine their ability to enhance the immune response against Aβ and induce immune-directed clearance from amyloid logs from the brain. One hundred and eighty male and female, 7.5 to 8.5 month old, heterozygous PDAPP transgenic mice were obtained from Charles River Laboratories. Mice were divided into 9 groups containing 15 to 23 animals per group for immunization with AN1792 and AN1528 in combination with different adjuvants. The animals were divided so that the sex, age and parents of the animals within the group were as close as possible. Adjuvants used were alun, MPL and QS21, each combined with two antigens, and Freund's adjuvant (FA) combined with AN1792 only. An additional group was immunized with AN1792 in PBS buffer with thymerosal preservative without adjuvant. The ninth group, as a negative control, was immunized with PBS alone. Preparation of aggregated peptides: human A ß1-40 (AN1528; California Peptides Inc., Napa, CA; lot ME0541), human A ß1-42 (AN1792; California Peptides Inc., lot ME0439) peptides, freshly solubilized for preparation of from a set of injections of freeze-dried powders that were stored dried at -20°C. For this purpose, 2 mg of the peptide was added to 0.9 ml of deionized water and the mixture was vortexed to prepare a relatively homogeneous solution or suspension. AN1528 was soluble at this step, unlike AN1792. Then equal volumes of 100 µlPL 203 431 B1 32 10x PBS were added (1x PBS: 0.15 NaCl, 0.01 M sodium phosphate, pH 7.5) and then AN1528 started to precipitate. vortexed again and incubated overnight at 37°C until used the next day. To prepare doses of alum vaccines (groups 1 and 5), Aβ peptide in PBS was added to Alhydrogel (2% aqueous aluminum hydroxide gel, Sargeant, Inc., Clifton, NJ) to reach a concentration of 100 μg A β-peptide per 1 mg of lun. 10x PBS was added to a final dose volume of 200 µl in 1x PBS. The suspension was gently stirred for approximately 4 hours at room temperature before injection. To prepare doses of MPL vaccines (groups 2 and 6), lyophilized powder (Ribi Immuno-Chem Research, Inc., Hamilton, MT; lot 67039-E0896B) was added to 0.2% aqueous triethylamine solution to a final conc. 1 mg/ml and vortexed. The mixtures were heated to 65 to 70°C for 30 s to obtain a slightly opaque and homogeneous micelle suspension. The solution was stored at 4°C. For each injection set, 100 µg of peptide per dose in 50 µl of PBS, 50 µg of MPL per dose (50 µl), and 100 µl of PBS per dose were mixed in a borosilicate tube immediately before use. To prepare vaccine doses from QS21 (groups 3 and 7), freeze-dried powder (Aquila, Framingham, MA; lot A7018R) was added to PBS, pH 6.6-6.7 to a final concentration of 1 mg/ml and wano. The solution was stored at -20°C. For each set of injections, 100 µg of peptide per dose in 50 µl of PBS, 25 µg of QS21 per dose in 25 µl of PBS, and 125 µl of PBS per dose were mixed in a borosilicate tube immediately before use. To prepare doses of vaccines with Freund's adjuvant (group 4), 100 μg of AN1792 was emulsified in 200 μl of PBS in a 1:1 (v/v) ratio with complete Freund's adjuvant (CFA) in a final volume of 400 μl for the first immunization. For subsequent immunizations, the antigen was similarly emulsified with incomplete Freund's adjuvant (IFA). For vaccines containing adjuvants alun, MPL or QS21, 100 µg per dose of AN1792 or AN1528 was combined with alun (1 mg per dose) or MPL (50 µg per dose) or QS21 (25 µg per dose), in a final volume of 200 µl of PBS and the vaccination was administered subcutaneously on the side between the shoulder blades. For the FA group, 100 μg of AN1792 was emulsified in a 1:1 (v/v) ratio with complete Freund's adjuvant (CFA) in a final volume of 400 μl and administered intraperitoneally for the first immunization, followed by booster doses of this same amount of immunogen in incomplete Freund's adjuvant (IFA) for five consecutive doses. For the group receiving AN1792 without adjuvant, 10 μg of AN1792 was combined with 5 μg of thimerosal in a final volume of 50 μl of PBS and administered subcutaneously. The ninth control group received only 200 μl of PBS by subcutaneous injection. Immunizations were performed biweekly for the first 3 doses, and then monthly, i.e. on days 0, 16, 28, 56, 85 and 112. Blood was collected from the animals 6-7 days after each immunization. , starting with the second dose, for measurement of antibody titers. Animals were sacrificed approximately one week after the final dose. The results were determined in an ELISA test measuring the levels of Aβ and APP in the brain and based on immunohistochemical assessment of the presence of amyloid plaques in histological sections of the brain. Additionally, titers of specific antibodies against Aß and Aβ-dependent, proliferative and cytokine responses were determined. Table 9 shows that the highest anti-A ß1-42 antibody titers were produced by FA from AN1792, titers that peaked after the fourth immunization (peak GMT: 75386) and then decreased by 59% after the final , sixth immunization. The peak antibody titer produced by MPL with AN1792 was 62% lower than that produced by FA (peak GMT: 28867) and so was reached early during immunization, after three doses, and decreased thereafter. was up to 28% of the peak value after the sixth immunization. The peak antibody titer generated by QS21 combined with AN1792 (GMT: 1511) was approximately 5-fold lower than that obtained with MPL. Furthermore, the kinetics of the response were slower when additional immunization was necessary to achieve a peak response. The titers produced by AN1792-bound alum were slightly higher than those obtained with QS21, and the response kinetics were faster. For AN1792 administered in PBS with thymerosal, the frequency and size of changes were slightly higher than those obtained for PBS alone. The peak titers produced by MPL and AN1528 (peak GMT 3099) were approximately 9-fold lower than those of AN1792. AN1528 associated with acorn was slightly immunogenic, with low titers produced in only a few animals. No antibody response was observed in control animals immunized alone. (12/21) b 1081 (17/20) 2366 (21/21) 1083 (19/21) 572 (18/21) MPL/AN1792 6241 (21/21) 28867 (21/21) 11242 (21/21) ) 5665 (20/20) 8204 (20/20) QS21/AN1792 30 (1/20) 227 (10/19) 327 (10/19) 1511 (17/18) 1188 (14/18) CFA/AN1792 10076 (15/15) 61279 (15/15) 75386 (15/15) 41628 (15/15) 30574 (15/15) Alun/AN1528 25 (0/21) 33 (1/21) 39 (3/20) 37 (1/20) 31 (2/20) MPL/AN1528 184 (15/21) 2591 (20/21) 1653 (21/21) 1156 (20/20) 3099 (20/20) QS21/AN1528 29 ( 1/22) 221 (13/22) 51 (4/22) 820 (20/22) 2994 (21/22) PBS+thymerosal 25 (0/16) 33 (2/16) 39 (4/16) 37 (3/16) 47 (4/16) PBS 25 (0/16) 25 (0/16) 25 (0/15) 25 (0/12) 25 (0/16) References: a Geometric mean antibody titers l measured relative to A ß1-42. b Number of responders per group e. The results of treatment with AN1792 or AN1592 with different adjuvants or thymerosal on cortical amyloid load in 12-month-old mice determined by a ELISA method are shown in Fig. 15. In PBS control mice, PDAPP mean level of total Aβ in the bark at the age of 12 months is 1817 ng/g. Significantly reduced Aβ levels were observed in mice treated with AN1792 plus CFA/IFA, AN1792 plus Aβ, AN1792 plus MPL, and QS21 plus AN1792. The reduction in Aβ axis was statistically significant (p <0.05) only for AN1792 plus CFA/IFA. However, as shown in Examples I and III, the effect of immunization on reducing Aβ levels was significantly greater in 15- and 18-month-old mice. Therefore, at least treatment with AN1792 plus a lun, AN1792 plus MPL, and AN1792 plus QS21 is expected to reach statistical significance in aged mice. In comparison, AN1792 plus the preservative thymerosal produced mean levels of Aβ almost the same as in PBS-treated mice. Similar results were obtained when comparing cortical A ß42 levels. The mean A ß42 level in the PBS controls is 1624 ng/g. Marked reductions in mean levels of 403, 1149, 620, and 714 were observed in mice treated with AN1792 plus CFA/IFA, AN1792 plus a lun, AN1792 plus MPL, and AN1792 plus QS21, respectively, with the reduction reaching statistical significance (p =0.05) for the group treated with AN1792 plus CFA/IFA. The mean value in the group treated with AN1792 with thymerosal was 1619 ng/g A ß42. X. Toxicity Analysis After completion of the tests described in Examples 2, 3 and 7, tissues were collected for histopathological evaluation. In addition, hematological and chemical analyzes were performed on the final blood samples from Examples 3 and 7. Most major organs were assessed, including the brain, lungs, lymphoid tissue, gastrointestinal tract, liver, kidneys, adrenal glands, and sex glands. Although occasional lesions were observed in the animals examined, no obvious differences were found in either the affected tissues or the severity of the lesions between AN1792-treated and untreated animals. There were no unique histopathological lesions in AN1782-immunized mice compared to PBS-treated or untreated mice. There were also no differences in the chemical analysis profile between the groups treated with PL 203 431 B1 34 adjuvant and the animals treated with PBS in Example 7. However, significant increases in several hematological parameters were observed between animals treated with AN1792 with Freund's adjuvant in Example 7 in compared to animals treated with PBS, but this type of effect was expected from Freund's adjuvant treatment and the associated peritonitis and does not indicate any adverse effect of AN1792 treatment. Detailed examination of the brain pathology of PDAPP mice was performed not as part of the toxicological evaluation but as part of the endpoints of the efficacy study. None of these studies revealed any signs of adverse effects on brain morphology. These results indicate that AN1792 treatment is well tolerated and at least largely free of side effects. XI. Prevention and treatment of patients Phase I single-dose trials were conducted to determine safety. The drug was administered in increasing doses to various patients starting at a dose of approximately 0.01, the level of presumed efficacy, and increased three-fold until the level reached 10 times the effective murine level. doses. Phase II trials were conducted to determine therapeutic efficacy. Patients in early to mid-stage Alzheimer's disease were selected using the Alzheimer's disease and Related Disorders Association (ADRDA) criteria for AD likelihood. Eligible patients scored in the Mini-Mental State Exam (MMSE) range of 12-26. Other selection criteria were that patients could survive the test duration and the absence of complicating data, such as concomitant use of medications that could influence treatment. The basic assessment of patients' functioning was performed using classic psychometric measurements, such as MMSE and ADAS, which is a general scale for assessing the condition and functioning of patients with Alzheimer's disease. These psychometric scales provide a measure of the progression of Alzheimer's disease. Appropriate quality of life scales can also be used to monitor treatment. The progression of the disease can also be monitored by MRI. Patients' blood profiles can also be monitored, including tests for antigen-specific antibody and T-cell responses. After basic measurements, patients are started on treatment. They were randomly assigned and treated with either the drug or a placebo. Patients were monitored for at least 6 months. Efficacy was defined as a significant reduction in progress in the treatment group relative to the placebo group. A Phase II trial was conducted to evaluate the transition of patients from non-Alzheimer's early memory loss, sometimes called age-related memory impairment (AAMI), to probable Alzheimer's disease, as defined by the ADRDA criteria. Patients at high risk of progressing to Alzheimer's disease were selected from a non-clinical population by screening reference populations for early signs of memory loss or other difficulties related to pre-Alzheimer's symptoms, family history of Alzheimer's disease, genetic factors risk factors, age, gender and other characteristics that indicate a high risk of Alzheimer's disease. Baseline scores for appropriate measures including the MMSE and ADAS were collected, along with other measures designed to assess a more normal population. These patient populations were divided into two appropriate groups with a comparison of placebo versus drug dose variants. The fate of patients from these populations was followed at intervals of approximately six months, and the end point for each patient was whether, at the end of the observation, the person would progress to the probable phase of Alzheimer's disease determined on the basis of the ADRDA criterion. XII. General materials and methods 1. Measurements of antibody titer l Blood was collected from mice by making a small puncture in the tail vein, and approximately 200 µl of blood was collected in a microcentrifuge tube. Blood was collected from guinea pigs by first shaving the hind shin area, then puncturing the metatarsal vein with an 18-gauge needle and collecting the blood into microcentrifuge tubes. The blood was allowed to clot for 1 hour at room temperature (RT), vortexed, and then centrifuged at 14,000 x g for 10 minutes to separate the clot from the serum. The sera were transferred to clean microcentrifuge tubes and stored at 4°C until titer determination. Antibody titers were measured using the ELISA method. 96-well microtiter plates (Costar EIA plates) were coated with 100 μl of a solution containing 10 μg/ml A ß42 or SAPP or other antigens as indicated in each individual case in Well Coating Buffer (0, 1 M sodium phosphate, pH 8.5, 0.1% sodium azide) and kept overnight at RT. The fluid was aspirated from the plates and the serum was added to the wells, starting with a 1/100 dilution in Specimen Diluent (0.014 M sodium phosphate, pH 7.4, 0.15 M NaCl, 0.6 % bovine serum albumin, 0.05% thimerosal). Seven consecutive 3-fold dilutions of the samples were made directly on the plates to reach a final dilution of 1/218,700. The diluted preparations were incubated in the coated wells of the plate for 1 hour at RT. The plates were then washed 4 times with PBS containing 0.05% Tween 20. Then a second antibody, goat anti-mouse Ig, conjugated with horseradish peroxidase (obtained from Boehringer Mannheim), was added to the wells. in an amount of 100 µl of a 1/3000 dilution in Specimen Diluent and incubated for 1 hour at RT. The plates were again washed 4 times with PBS, Tween 20. To develop the chromogen, 100 μl of Slow TMB (3,3',5,5'-tetramethyl-benzidine obtained from Pierce Chemicals) was added to each well and incubated for 15 minutes at RT. The reaction was stopped by adding 25 µl of 2M H 2 SO 4 . The color intensity was then read in Molecular Devices Vmax at 450 nm-650 nm. Titers were defined as the reciprocal of the serum dilution resulting in half the maximum OD. Typically, the maximum OD was read from an initial dilution of 1/100, except in cases of very high titers where a higher initial dilution was necessary to establish the maximum OD. If the 50% point was between two dilutions, linear extrapolation was performed to determine the final titer. To calculate the geometric mean antibody titer, titers lower than z 100 were conventionally designated as a titer value of 25. 2. Lymphocyte proliferation test Mice were anesthetized with isoflurane. The spleen was removed and washed twice in 5 ml of PBS containing 10% heat-inactivated fetal bovine serum (PBS-FBS), homogenized in 50 μ Centricon Unit (Dako A/S, Denmark) in 1.5 ml of PBS-FBS. FBS for 10 seconds at 10 rpm in Medimachine (Dako) and then filtered through a 100 µ nylon sieve. Spleen lymphocytes were washed once with 15 ml of PBS-FBS, then pelleted by centrifugation at 200 x g for 5 minutes. Red blood cells were lysed by suspending the pellet in 5 ml of buffer containing 0.15 M NH 4 Cl, 1 M KHCO 3, 0.1 M NaEDTA, pH 7.4 for 5 minutes at RT. The leukocytes were then washed as described above. Freshly isolated spleen cells (105 per well) were cultured in triplicate sets in 96-well U-bottomed tissue culture microtiter plates (Corning, Cambridge, MA) in RPMI 1640 medium ( JRH Biosciences, Lenexa, KS) supplemented with 2.05 ml of L-glutamine, 1% α-penicillins/streptomycins and 10% heat-inactivated FBS, for 96 hours at 37°C. Various peptides A ß, A ß1-16, A ß1-40, A ß1-42 or the reverse amino acid sequence A ß40-1 were also added at doses ranging from 5 µM to 0.18 µM in four steps. . Cells in control wells were cultured with concanavalin A (Con A) (Sigma, catalog no. C-5275, at a concentration of 1 µg/ml) without adding protein. 3 H-thymidine (1 µCi/well obtained from Amersham Corp., Arlington Heights IL) was added to the cells for the last 24 hours. Cells were then collected on UniFilter plates and radioactivity was measured sc with a Top Count Microplate Scintillation Counter (Packard Instruments, Downers Grove, IL). The results were expressed as pulses per minute (cpm) of radioactivity incorporated into the insoluble macromolecules. 4. Preparation of brain tissues After killing the animals, the brains were removed and one hemisphere was prepared for immunohistochemical analysis, and from the other hemisphere, three brain regions were dissected (hippocampus, cortex and cerebellum) and used to measure the concentration with different Aβ proteins and APP forms using specific ELISA tests (Johnson-Wood et al., supra). Tissues intended for ELISA tests were homogenized in 10 volumes of ice-cold guanidine buffer (5.0 M guanidine-HCl, 50 mM Tris-HCl, pH 8.0). The homogenates were mixed by gentle shaking in an Adams Nutator (Fisher) for 3-4 hours at RT and stored at -20°C before Aβ and APP determination. Previous experiments have shown that analytical preparations were stable under these storage conditions and that synthetic protein Aβ (Bachem) could be quantitatively recovered after mixing homogenates of control brain tissue from mouse litters (Johnson-Wood and others, supra). 5. Measurement of A ß levels Brain homogenates were diluted 1:10 with ice-cold Casein Diluent (0.25% casein, PBS, 0.05% sodium azide, 20 µg/ml aprotinin, 5 mM EDTA pH 8.0, 10 µg /ml leupeptin) and then centrifuged at 16,000 x g for 20 minutes at 4°C. Synthetic Aβ peptide standards (amino acids 1-42) and APP standards were prepared to contain 0.5 M guanidine and 0.1% bovine serum albumin (BSA) in the final preparation. The "total" A ß sandwich ELISA used monoclonal antibodies (mA ß) 266, specific for amino acids 13-28 A ß (Seubert et al.) as a capture antibody, and biotinylated mA ß 3D6, specific for amino acids 1-5 A ß (Johnson-Wood et al.) as a reporter antibody. 3D6 mA ß does not recognize secreted APP or full-length APP, but only detects A ß with an N-terminal aspartic acid. This test has lower than the sensitivity limit of ~ 50 µ g/ml (11 µ M) and does not show cross-reactivity with endogenous mouse A ß protein at concentrations up to 1 ng/ml (Johnson-Wood et al., supra The A ß1-42-specific sandwich ELISA uses mA ß 21F12, specific for amino acids 33-42 A ß (Johnson-Wood et al.) as the capture antibody. Biotinylated mA ß 3D6 is also with the antibody reporter in this assay, which has a lower sensitivity limit of approximately 125 µ g/ml (28 µ M, Johnson-Wood et al.). For A ß ELISA tests, 96-well wells immunoassay plates (Costar) were coated with 100 µl of mA ß 266 (at a concentration of 10 µg/ml) or mA ß 21F12 (at a concentration of 5 µg/ml) with overnight incubation at RT. The solution was removed by aspiration and the wells were blocked by adding 200 μl of 0.25% human serum albumin in PBS buffer for at least 1 hour at RT. The blocking solution was removed and the plates were stored dry at 4°C until use. Before use, the plates were hydrated with Wash Buffer [Tris-buffered saline (0.15 M NaCl, 0.01 M Tris-HCl, pH 7.5), plus 0.05% Tween 20]. Samples and standards were added in triplicate equal parts of 100 µl per well and then incubated overnight at 4°C. The plates were washed at least 3 times with Wash Buffer between each test step. Biotinylated mA ß 3D6, diluted to 0.5 µl/ml in Casein Assay Buffer (0.25% casein, PBS, 0.05% Tween 20, pH 7.4) was added and incubated in the wells for 1 hour e in RT. Avidin-horseradish peroxidase conjugate (Avidin-HRP obtained from Vector, Burlingame, CA) diluted 1:4000 in Casein Assay Buffer was added for 1 hour at RT. The colorimetric substrate, Slow TMB-ELISA (Pierce), was added and allowed to react for 15 minutes at RT, after which the enzymatic reaction was stopped by adding 25 µl of 2N H 2 SO 4 . The reaction product was determined using Molecular Devices Vmax measuring the difference in absorption at 450 nm and 650 nm. 6. Measurement of APP levels Two different APP tests were used. The first, called APP-a/FL, recognizes both APP-alpha (a) and the full-length (FL) forms of APP. The second test recognizes only APP-a. The APP-a/FL test recognizes the secreted form of APP including the first 12 amino acids A ß. Because the reporter antibody (2H3) is not specific for the α-clamp site located between amino acids 612-613 of APP695 (Esch et al., Science 248, 1122-1124 (1990)), this test also recognizes complete APP length (APP-FL). Preliminary experiments with immobilized APP antibodies against the cytoplastic tail of APP-FL to remove APP-FL from brain homogenates suggested that approximately 30-40% of APP-a/FL APP is FL (data not presented). The capture antibody in both the APP-a/FL and APP-a assays is mA ß 8E5 raised against amino acids 444 to 592 of the APP695 form (Games et al., supra). The mA ß reporter for the APP-a/FL assay is mA ß 2H3, a specific form of APP695 for amino acids 597-608 (Johnson-Wood et al., supra), and the reporter antibody for the APP-a test is the biotinylated derivative of mA ß 16H9, prepared against amino acids 605 to 611 APP. The lower limit of sensitivity of the APP-a/FL test is 11 ng/ml (150 µM) (Johnson-Wood et al.), and for the APP-a-specific test is 22 ng/ml (0.3 nM). . For both APP assays, wells of 96-well EIA plates were coated with mA β 8E5 as described above for mA β 266. Purified, recombinant secreted APP- α was used as a standard for the APP- α assay and the APP- α/FL assay (Esch et al. , supra). Brain homogenate samples in 5 M guanidine were diluted 1:10 in ELISA Specimen Diluent (0.014 M phosphate buffer, pH 7.4, 0.6% bovine serum albumin, 0.05% thymerosal, 0.5 M NaCl, 0, 1% NP40). They were then diluted 1:4 in Specimen Diluent containing 0.5 M guanidine. The diluted homogenates were centrifuged at 16,000 x g for 15 seconds at RT. APP standards and samples were added to the plates in duplicate of the same amounts and incubated for 1.5 hours at RT. Biotinylated 2H3 and 16H9 reporter antibodies were incubated with the samples for 1 hour at RT. Streptavidin e-alkaline phosphatase (Boehringer Mannheim) diluted 1:1000 in Specimen Diluent was incubated in the wells for 1 hour at RT. The fluorescent substrate, 4-methyl-umbelliferyl phosphate, was added and incubated for 30 minutes at RT, and then the plates were read in a Cytofluor tm 2350 fluorimeter (Millipore) at 365 nm excitation and 450 nm emission. 7. Immunohistochemistry Brains were fixed for 3 days at 4°C in 4% paraformaldehyde in PBS, and then stored for 1-7 days at 4°C in 1% paraformaldehyde, PBS before sectioning. 40 micron thick coronal histological sections were cut on a vibratome at RT and stored in antifreeze buffer (30% glycerol, 30% ethylene glycol in phosphate buffer) at -20°CPL 203 431 B1 37 before processing a immunohistochemistry. For each brain, 6 fragments at the level of the dorsal hippocampus, each separated by consecutive 240 µm gaps, were incubated overnight with one of the following antibodies: (1) biotinylated anti-A ß (mA ß, 3D6 , specific for human Aß) diluted to a concentration of 2 µg/ml in PBS and 1% horse serum; or (2) biotinylated mAβ, specific for human APP, 8E5, diluted to a concentration of 3 μg/ml in PBS and 1.0% horse serum; or (3) glial fibrillary acidic protein-specific mAβ (GFAP; Sigma Chemical Co.) diluted 1:500 in 0.25% Triton X-100 and 1% horse serum in Tris-buffered saline, pH 7, 4 (TBS); or (4) mA ß specific for CD11b, MAC-1 antigen, (Chemicon International) diluted 1:100 in 0.25% Triton X-100 and 1% rabbit serum in TBS; or (5) mA β specific for MHC II antigen, (Pharmigen) diluted 1:100 in 0.25% Triton X-100 and 1% rabbit serum in TBS; or (6) CD 43-specific rat mAβ, (Pharmingen) diluted 1:100 with 1% rabbit serum in PBS; or (7) rat mAβ specific for CD 45RA, (Pharmingen) diluted 1:100 with 1% rabbit serum in PBS; or (8) rat monoclonal Aβ specific for CD 45RB, (Pharmingen) diluted 1:100 with 1% rabbit serum in PBS; or (9) rat monoclonal Aβ specific for CD 45, (Pharmingen) diluted 1:100 with 1% rabbit serum in PBS; or (10) biotinylated hamster polyclonal Aβ specific for CD3e, (Pharmingen) diluted 1:100 with 1% rabbit serum in PBS; or (11) CD3-specific rat mAβ, (Serotec) diluted 1:200 with 1% rabbit serum in PBS; or with (12) a PBS solution containing no primary antibodies, containing 1% normal horse serum. Histological sections exposed to the antibody solutions listed in 1, 2 and 6-12 above were previously treated a solution of 1.0% Triton X-100, 0.4% hydrogen peroxide in PBS for 20 minutes at RT to block endogenous peroxidases. They were then incubated overnight at 4°C with primary antibodies. Sections treated with 3D6 or 8E5 or CD3e mA ß were then reacted for 1 hour at RT with the horseradish peroxidase-avidin-biotin complex with the components of the set "A" and "B" diluted 1:75 in PBS (Vector Elite Standard Kit, Vector Labs, Burlingame, CA.). Sections treated with antibodies specific for CD 45RA, CD 45RB, CD 45, CD3 and a PBS solution without primary antibodies were incubated for 1 hour at RT with biotinylated anti-rat IgG antibodies (Vector) diluted 1:75, respectively. in PBS or biotinylated anti-mouse IgG antibodies (Vector) diluted 1:75 in PBS. The sections were then reacted for 1 hour at RT with the horseradish peroxidase-avidin-biotin complex with kit components "A" and "B" diluted 1:75 in PBS (Vector Elite Standard Kit, Vector Labs, Burlingame, CA.). Sections were developed in 0.01% hydrogen peroxide, 0.05% 3,3'-diaminobenzidine (DAB) at RT. Sections intended for incubation with antibodies specific for GFAP, MAC-1 and MHC II were previously treated with 0.6% hydrogen peroxide at RT to block endogenous peroxidases and then incubated overnight at 4°C with primary antibodies lami. Sections treated with GFAP antibody were incubated for 1 hour at RT with biotinylated anti-mouse IgG antibodies produced in horses (Vector Laboratories; Vectastain Elite ABC Kit) diluted 1:200 in TBS. The sections were then incubated for 1 hour with a peroxidase-avidin-biotin complex (Vector Laboratories; Vectastain Elite ABC Kit) diluted 1:1000 in TBS. Sections incubated with MAC-1 and MHC II-specific mAβ antibodies as primary antibodies were sequentially reacted for 1 hour at RT with biotinylated anti-rat IgG antibodies generated in rabbits, diluted 1:200 in TBS , then incubated for 1 hour with the horseradish peroxidase-avidin-biotin complex diluted 1:1000 in TBS. Sections incubated with antibodies specific for GFAP, MAC-1 and MHC II were developed by incubating them at RT with 0.05% DAB, 0.01% hydrogen peroxide, 0.04% nickel chloride, TBS for 4 and 11 minutes, respectively. . Immunolabeled sections were mounted on glass slides (VWR, Superfrost slides), air-dried overnight, immersed in Propar (Anatech), and coverslipped using AC Permount (Fisher) as a mounting medium. To counterstain Aβ plates, a subset of GFAP-positive sections were placed on Superfrost slides and incubated in aqueous 1% Thioflavin S (Sigma) for 7 minutes after immunohistochemical processing. Then, the sections were dehydrated and cleaned in Propar, after which coverslips were placed on them and mounted using Permount.PL 203 431 B1 38 8. Image analysis Videometric 150 Image Analysis System was used for quantitative assessment of immunoreactive sections ( Oncor, Inc. Gaithersburg, MD) interfaced with a Nikon Microphot-FX microscope via a CCD e-video camera and a Sony Trinitron monitor. The image of the sections was stored in a video buffer and a color and saturation threshold was determined to select and count the total pixel area occupied by the immunolabeled structures. For each slice, the hippocampus was manually outlined and the total pixel area occupied by the hippocampus was calculated. The percentage of amyloid load was measured as: (fraction of the hippocampal area containing mA-immunoreactive ß 3D6) x 100. Similarly, the percentage of neuritic load was measured as: (fraction of the hippocampal area containing dystrophic mA-reactive neurites ß 8E5) x100. A C-Imaging System (Comprix, Inc., Cranberry Township, PA) using the Simple 32 Software Application was connected to a Nikon Microphot-FX microscope via an e-Optronics camera and used to quantify the percentage of retrocal- loxal cortex involved by GFAP- positive astrocytes and MAC-1- and MHC II-positive microglia. An image of the immunoreactive sections was stored in a video buffer and a monochrome threshold was determined to select and count the total pixel area occupied by immunolabeled cells. For each section, the retrocallosal cortex (RSC) was manually outlined and the total pixel area occupied by the RSC was calculated. The percentage of astrocytosis was defined as: (fraction of the RSC area occupied by GFAP-reactive astrocytes) x 100. Similarly, the percentage of microgliosis was defined as: (fraction of the RSC area occupied by MAC-1 and MHC II-reactive microglia) x 100. For all image analyzes 6 sections at the level of the dorsal hippocampus, each separated by consecutive 240 µm gaps, were quantified for each animal. In all cases, the medicinal status of the animals was unknown to the observer. Although the above invention has been described in detail for the purpose of explanation and understanding, it is obvious that certain modifications may be made within the scope of the appended claims. All references and patent documents cited are hereby incorporated by reference in their entirety. - media for all purposes to the extent they are mentioned.PL 203 431 B1 39PL 203 431 B1 40 PL PL PL

Claims (54)

1. Claims 1. A pharmaceutical composition characterized by comprising an immunogenic agent effective to induce an immune response comprising anti-Aβ antibodies in the patient and a pharmaceutically acceptable adjuvant, the agent being selected from the group consisting of: (and ) A ß (ii) a fragment of at least five contiguous amino acids A ß42; and (iii) a nucleic acid encoding (i) or (ii); and the adjuvant is selected from the group consisting of aluminum, aluminum hydroxide, aluminum phosphate, aluminum sulfate, 3-de-O-acylated monophosphoryl lipid A, M-CSF and GM-CSF, oil-in-water emulsions such as squalene or peanut oil, MF59, SAF, CpG, polymeric or monomeric amino acids such as poly(glutamic acid) or polylysine, muramyl peptides (e.g. N-acetylmuramyl-L-threonyl-D-isoglutamine (thr-MDP), N-acetylnor-muramyl-L-alanyl-D-isoglutamine (nor-MDP), N-acetylmuramyl-L-alanyl-D-isoglutaminyl-L-alanine-2-(1'-2'dipalmitoyl-sn-glycero-3 -hydroxyphosphoryloxy)ethylamine (MTP-PE), N-acetylglucose-minyl-N-acetyl-muramyl-L-A1-D-isoglu-L-Ala-dipalmitoxypropylamide (DTP-DPP)) and other cell wall components bacterial, such as trehalose dimycolinate (TDM), cell wall skeleton (CWS), MPL+CWS, saponin adjuvants (QS21), ISCOM (immunostimulatory complexes), cytokines such as interleukins (IL-1, IL-2 and IL-12), macrophage colony-stimulating factor (M-CSF), tumor necrosis factor (TNF); and A ß42 has the natural human sequence: H 2 N-Asp-Ala-Glu-Phe-Arg-His-Asp-Ser-Gly-Tyr-Glu-Val- -His-His-Gln-Lys-Leu- Val-Phe-Phe-Ala-Glu-Asp-Val-Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu-Met-Val- -Gly-Gly-Val-Val-Ile-Ala -OH. 2. The composition according to claim 1, characterized in that the agent is encapsulated in a particle. 3. The composition according to claim 2, characterized in that the particle is a polylactide-polyglycolide (PLPG) copolymer particle. 4. The composition according to claim 1, characterized in that A ß is A ß43, A ß42, A ß41, A ß40 or A ß39. 5. The composition according to claim 1, characterized in that the A ß fragment comes from the N-terminal half of A ß. 6. The composition according to claim. 1, characterized in that the A ß fragment contains A ß1-5. 7. The composition according to claim. 5, characterized in that the A ß fragment is A ß1-5. 8. The composition according to claim. 5, characterized in that the A ß fragment is A ß1-6. 9. The composition according to claim 1. 5, characterized in that the A ß fragment is A ß1-12. 10. The composition according to claim. 1, wherein the A ß fragment is selected from the group consisting of A ß1-5, A ß1-6, A ß1-12, A ß13-28, A ß17-28, A ß25-35, A ß33-42 , A ß35-40 and A ß35-42. 11. The composition according to claim. 1-10, characterized in that it contains at least 10 µg of A ß or a fragment thereof. 12. The composition according to claim. 1-10, characterized in that it contains at least 20 µg of A ß or a fragment thereof. 13. The composition according to claim 1-10, characterized in that it contains at least 50 µg of A ß or a fragment thereof. 14. The composition according to claim 1. 1-10, characterized in that it contains at least 100 µg of A ß or a fragment thereof. 15. Use of an immunogenic agent effective in inducing an immune response comprising antibodies against Aβ for the manufacture of a medicament for the treatment or prophylaxis of a disease characterized by amyloid logs in a patient, characterized in that the agent comprises: (i) Aβ (ii) a fragment of at least five contiguous A ß42 amino acids; or (iii) a nucleic acid encoding (i) or (ii); and A ß42 has the natural human sequence: H 2 N-Asp-Ala-Glu-Phe-Arg-His-Asp-Ser-Gly-Tyr-Glu-Val-His-His-Gln-Lys-Leu-Val -Phe-Phe-Ala-Glu-Asp-Val-Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu-Met-Val- Gly-Gly-Val-Val-Ile-Ala-OH . 16. Use according to claims. 15, wherein the medicament further comprises a pharmaceutically acceptable adjuvant selected from the group consisting of aluminum, aluminum hydroxide, aluminum phosphate, aluminum sulfate, 3-de-O-acylated monophosphorylated lipid A, M-CSF and GM-CSF, oil emulsions in water, such as squalene or peanut oil, MF59, SAF, CpG, polymeric or monomeric amino acids, PL 203 431 B1 41 such as poly(glutamic acid) or polylysine, muramyl peptides (e.g. N-acetylmuramyl-L-threonyl- D-isoglutamine (thr-MDP), N-acetylnormuramyl-L-alanyl-D-isoglutamine (nor-MDP), N-acetylmuramyl-L-alanyl-D-isoglutaminyl-L-alanine-2-(1'-2' di-palmitoyl-sn-glycero-3-hydroxyphosphoryloxy)ethylamine (MTP-PE), N-acetylglucosaminyl-N-acetylmuramyl-L-A1-D-isoglu-L-Ala-di-palmitoxypropylamide (DTP-DPP)) , or other bacterial cell wall components such as trehalose dimycolinate (TDM), cell wall skeleton (CWS), MPL+CWS, saponin adjuvants (QS21), ISCOMs (immunostimulatory complexes), cytokines such as interleukins (IL -1, IL-2 and IL-12), macrophage colony-stimulating factor (M-CSF), tumor necrosis factor (TNF). 17. Use according to claims. 15, wherein the agent is encapsulated in the particle. 18. Use according to claims. 16, wherein the agent is encapsulated in the particle. 19. Use according to claim. 17, wherein the particle is a polylactide-polyglycolide (PLPG) copolymer particle. 20. Use according to claim. 18, wherein the particle is a polylactide-polyglycolide (PLPG) copolymer particle. 21. Use according to claim. 15, wherein A ß is A ß43, A ß42, A ß41, A ß40 or A ß39. 22. Use according to claim. 15, wherein the Aβ fragment is derived from the N-terminal half of Aβ. 23. Use according to claim 15, wherein the Aβ fragment comprises Aβ1-5. 24. Use according to claim 22, wherein the A ß fragment is A ß1-5. 25. Use according to claim. 22, wherein the A ß fragment is A ß1-6. 26. Use according to claim. 22, wherein the A ß fragment is A ß1-12. 27. Use according to claim 15, wherein the Aβ fragment is selected from the group consisting of Aβ1-5, Aβ1-6, Aβ1-12, Aβ13-28, Aβ17-28, Aβ25-35, Aβ33-42, Aβ35- 40 and A ß35-42. 28. Use according to claim 15-27, wherein the amount of sc A ß or fragment thereof is at least 10 µg. 29. Use according to claim. 15-27, wherein the amount of sc Aβ or fragment thereof is at least 20 µg. 30. Use according to claim. 15-27, wherein the amount of sc A ß or fragment thereof is at least 50 µg. 31. Use according to claim 15-27, wherein the amount of sc A ß or fragment thereof is at least 100 µg. 32. Use according to claim 15-27, in which the patient is a human. 33. Use according to claim 28, wherein the patient is a human. 34. Use according to claim 29, wherein the patient is a human. 35. Use according to claim 30, wherein the patient is a human. 36. Use according to claim 31, wherein the patient is a human. 37. Use according to claim 15-27, wherein the disease is Alzheimer's disease. 38. Use according to claim 28, wherein the disease is Alzheimer's disease. 39. Use according to claim 29, wherein the disease is Alzheimer's disease. 40. Use according to claim 30, wherein the disease is Alzheimer's disease. 41. Use according to claim 31, wherein the disease is Alzheimer's disease. 42. Use according to claim 15-27, in which the patient has no symptoms. 43. Use according to claim 28, in which the patient is asymptomatic. 44. Use according to claim 29, in which the patient is asymptomatic. 45. Use according to claim 30, in which the patient is asymptomatic. 46. Use according to claim 31, in which the patient is asymptomatic. 47. Use according to claim 15-27, in which the patient is less than 50 years old. 48. Use according to claim 28, in which the patient is less than 50 years old. 49. Use according to claim 29, in which the patient is less than 50 years old. 50. Use according to claim 30, in which the patient is less than 50 years old. 51. Use according to claim 31, in which the patient is less than 50 years old. 52. Use according to claim 15-27, wherein the patient has inherited risk factors indicating susceptibility to Alzheimer's disease. 53. Use according to claim 28, wherein the patient has inherited risk factors indicating susceptibility to Alzheimer's disease. 54. Use according to claim 29, wherein the patient has inherited risk factors indicating susceptibility to Alzheimer's disease.PL 203 431 B1 4255. Use according to claim 29. 30, wherein the patient has inherited risk factors indicating susceptibility to Alzheimer's disease.56. Use according to claim 31, wherein the patient has inherited risk factors indicating susceptibility to Alzheimer's disease.57. Use according to claim 15-27, wherein the patient has no known risk factors for Alzheimer's disease.58. Use according to claim 28, wherein the patient has no known risk factors for Alzheimer's disease.59. Use according to claim 29, wherein the patient has no known risk factors for Alzheimer's disease.60. Use according to claim 30, wherein the patient has no known risk factors for Alzheimer's disease.61. Use according to claim 31, wherein the patient has no known risk factors for Alzheimer's disease.62. Use according to claim 21, in which A ß occurs in aggregated form.63. Use according to claim 15-27, wherein the drug is administered orally, subcutaneously, intramuscularly, topically or intravenously.64. Use according to claim 28, wherein the drug is administered orally, subcutaneously, intramuscularly, topically or intravenously.65. Use according to claim 29, wherein the drug is administered orally, subcutaneously, intramuscularly, topically or intravenously.66. Use according to claim 30, wherein the drug is administered orally, subcutaneously, intramuscularly, topically or intravenously.67. Use according to claim 31, wherein the drug is administered orally, subcutaneously, intramuscularly, topically or intravenously.68. Use according to claim 63, in which the drug is administered intramuscularly or subcutaneously.69. Use according to claim 64-67, in which the drug is administered intramuscularly or subcutaneously.70. Use according to claim 15-20, wherein the agent is an effective dose of a nucleic acid encoding Aβ or a fragment of at least five contiguous amino acids Aβ42, wherein the nucleic acid is expressed in the patient to produce Aβ or a fragment of least five adjacent amino acids A ß42 causing an immunological response 71. Use according to claim 70, in which the drug is administered topically.72. Use according to claim 71, in which the drug is applied topically in the form of a patch.73. Use according to claim 15-27, in which the patient is monitored for immune response.74. Use according to claim 28, wherein the patient is monitored for immune response.75. Use according to claim 29, wherein the patient is monitored for immune response.76. Use according to claim 30, wherein the patient is monitored for immune response.77. Use according to claim 31, in which the patient is monitored for immune response.PL 203 431 B1 43 DrawingsPL 203 431 B1 44PL 203 431 B1 45PL 203 431 B1 46PL 203 431 B1 47PL 203 431 B1 48PL 203 431 B1 49PL 203 431 B1 50PL 203 431 B1 51PL 203 431 B1 52PL 203 431 B1 53PL 203 431 B1 54PL 203 431 B1 55PL 203 431 B1 56 Publishing Department of the Polish Office of the Republic of Poland Price PLN 6.00 per number PL PL PL