JP2016094422A - Compound and method for treating alzheimer's disease and familial dementia - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide protein for treating Alzheimer's disease, familial Danish dementia, and familial British dementia in mammals including human.SOLUTION: There is provided use of Bri2 (integral membrane protein 2B, ITM2B) for reducing coagulation of Aβ-peptide to amyloid fibril. Protein to be used is selected from: protein containing amino acid sequence which has at least 70% of identity to the residue of 90 to 236 of human-derived Bri2; and protein containing amino acid sequence which has at least 70% of identity to one of a Brichos domain of Bri2 derived from human, chimpanzee, bovine, swine, mouse or rat. However, isolated protein does not contain amino acid sequence having at least 70% of identity to the residue of 1 to 89 of human-derived Bri2, or to human ABri23.SELECTED DRAWING: Figure 1

Description

  The present invention relates to the field of medicine. More specifically, the invention relates to pharmaceuticals and treatments for the treatment of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals such as humans.

  Increasing numbers of neurodegenerative conditions such as Alzheimer's disease and familial British or Danish dementia are associated with protein misfolding and aggregation. These diseases are characterized by protein deposition in the brain parenchyma and cerebral arteries and occur in genotype or sporadic form. Although these diseases have a variety of clinical symptoms, they share some common pathological features such as the presence of neuronal defects, protein aggregates, and tau tangles. From a biochemical point of view, the proteins involved tend to form a β-sheet structure and tend to aggregate in amyloid fibrils. Alzheimer's disease and familial British or Danish dementia display several similar neuropathological features. Amyloid plaques, neurofibrillary tangles, Congoamyloid-satisfied vasculopathy and neurodegeneration.

  Alzheimer's disease is one of the most common causes of dementia in humans. It is a chronic and fatal disease with neuronal degeneration of the affected patient's brain characterized by the presence of amyloid plaques consisting of extracellular deposits of amyloid β-peptide (Aβ-peptide). Neuronal atrophy caused by Aβ aggregation results in a deficiency of acetylcholine and other signaling substances. Aβ-peptide with 40-42 amino acid residues is produced by processing of amyloid precursor protein (APP, 695-770 amino acid residues), a type I membrane protein normally expressed by neurons of the central nervous system Although known, the reasons for this processing are not always fully understood. The released Aβ peptide contains part of the transmembrane region of APP (Aβ residues 29-40 / 42) and is a mismatched helix, ie a helix composed of amino acids with a high propensity to form β-strands including. Aβ is prone to misfolding and aggregation if it deviates from its stabilizing membrane environment.

  Bri2 (SEQ ID NO: 1, also called integral membrane protein 2B, ITM2B) is a 266-residue type II membrane protein with ubiquitous expression (FIG. 1) whose function and folding structure are unknown. Bri2 is proteolytically cleaved at three locations; cleavage by furin in the C-terminal region generates a 23-residue peptide (ABri23), and processing of the ectodomain by ADAM10 is performed from the membrane-bound N-terminal portion to Brichos. Domain release results, and transmembrane cleavage by SPPL2a / 2b liberates intracellular domains. Familial British and Danish dementia results from mutations in the Bri2 gene, which results in the loss of the stop codon and then two different 11-residue extensions of the C-terminal part, and furin cleavage Later, it results in the generation of 34-residue peptides (ABri and ADan, respectively) on behalf of normally released ABri23. The longer the peptide, the more likely it is to aggregate into amyloid fibrils and deposit in brain tissue or cerebral blood vessels, with concomitant neuronal loss and dementia.

  Recent studies have shown that Bri2 and Aβ co-localize with amyloid plaques in the brain parenchyma and cerebral blood vessels, suggesting that the protein interacts at some stage during misfolding and aggregation To do. When using transfected cell lines, Bri2 was found to interact with APP and regulate APP processing by increasing the fragments produced by β-secretase. Generation of a fusion protein comprising Bri2 and Aβ40 indicates that the Bri protein can affect Aβ aggregation, and when using a transgenic mouse model, it is suggested that ABri23 interacts with Aβ42 and prevents its aggregation (Kim et al., J. Neurosci. 28: 6030-6036 (2008); WO 2009/009396 pamphlet). It has also been shown that Aβ production can be reduced or prevented by proteins containing the first 102 amino acid residues of Bri2 (WO 2006/138355).

  Current therapeutic approaches to the treatment of Alzheimer's disease are primarily directed to the treatment of the symptoms, choline replacement therapy, eg, inhibition of acetylcholinesterase, low molecular weight inhibitors that interact with soluble Aβ oligomers, and already formed A so-called β-sheet breaker that prevents extension of the formed β-sheet structure.

Another strategy that has been proposed to prevent aggregation has been to use molecules that are functionally defined as chaperones. Chaperones play an important role by helping to fold proteins correctly in complex intracellular environments. Many molecular chaperones, such as heat shock proteins (Hsp), are known to be important in the folding process and have been extensively studied. Some of these chaperones are clearly associated with and can influence the amyloid fibril formation of certain polypeptides. Aggregation of Aβ _1-42 is inhibited by Hsp90 or the combination Hsp70 / Hsp40 (CG Evans et al., J Biol Chem 281: 33182-33191, 2006). In addition, extracellular chaperone clusterins (apolipoprotein J) are a number of polypeptides including Aβ (E Matsubara et al., Biochem J 316 (Pt2): 671-679, 1996) and fragments of prion proteins (S McHattie and N Edington, Biochem Biophys Res Commun
259: 336-340 (1999), which has been shown to inhibit fibril formation. The role of structurally diverse chaperones in preventing amyloid disease has not been established, and several reports have even shown that protein chaperones promote amyloid fibril formation (eg, SK DevBurman et al., Proc Nat Acad Sci USA 94: 13938-13943, 1997). In addition to molecular chaperones, the action of chemical and pharmacological chaperones has been studied in the context of misfolding diseases (diseases caused by misfolding). No effective therapy using chaperones or other means has been found so far for any amyloid disease.

  Monoclonal antibodies against Aβ peptide prevent aggregation into neurotoxic fibrils and dissolve already formed amyloid. However, antibody therapy is very expensive and involves a variety of serious side effects. Vaccination with β-amyloid in a transgenic mouse model of Alzheimer's disease showed a significant reduction in the number of amyloid plaques and overall amyloid burden, and even some improvement in cognitive ability.

  The object of the present invention is to reduce the aggregation of Aβ-peptides on amyloid fibrils.

  It is also an object of the present invention to reduce the formation of amyloid plaques consisting of extracellular deposition of Aβ-peptide in the mammalian brain.

  Another object of the present invention is to provide new therapeutic options for the treatment of Alzheimer's disease in mammals, including humans.

  It is also an object of the present invention to provide a novel therapeutic option for the treatment of familial Danish dementia and / or familial British dementia in mammals including humans.

  With respect to these and other objects that will become apparent from the description below, the present invention provides, according to the first aspect, residues 90-236 of human-derived Bri2 (SEQ ID NO: 2) and human (SEQ ID NO: 5), chimpanzee (sequence No. 6) isolated from the group of proteins consisting of Bri2's Brichos domain from bovine (SEQ ID NO: 7), pig (SEQ ID NO: 8), mouse (SEQ ID NO: 9) and rat (SEQ ID NO: 10) Provide protein.

  Surprisingly, it has been found that this isolated protein has the ability to reduce amyloid fibril formation and / or reduce Aβ-peptide aggregation. This is particularly surprising considering the structural disparity between the target ABri23 (SEQ ID NO: 4) and the Aβ peptide (SEQ ID NO: 11-12). The present invention is based on the surprising insights about the previously unknown substrate specificity of this isolated protein that contains the Brichos domain of Bri2, but does not contain the ABri23 sequence, as disclosed herein. Yes.

  In one embodiment, the isolated protein is selected from the group of proteins consisting of residues 90-236 of Bri2 from human (SEQ ID NO: 2); and the Brichos domain of Bri2 from human (SEQ ID NO: 5) . In certain embodiments, the isolated protein consists of residues 90-236 of Bri2 from human (SEQ ID NO: 2) or the Brichos domain of Bri2 from human (SEQ ID NO: 5).

  The isolated protein according to the present invention is useful as a medicament in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia, particularly in mammals including humans It is. In a preferred embodiment, the isolated protein according to the present invention is useful for the treatment of Alzheimer's disease.

  The invention, according to another aspect, is derived from a human for use in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans. A protein comprising an amino acid sequence having at least 70% identity to residues 90-236 (SEQ ID NO: 2) of Bri2; and human (SEQ ID NO: 5), chimpanzee (SEQ ID NO: 6), bovine (SEQ ID NO: 7) ), Porcine (SEQ ID NO: 8), mouse (SEQ ID NO: 9) and rat (SEQ ID NO: 10) from a protein comprising an amino acid sequence having at least 70% identity to any one of Bri2's Brichos domains An isolated protein selected from the group consisting of residues 1 to 89 of human-derived Bri2 Provided that it does not contain an amino acid sequence having at least 70% identity to said; and said protein does not contain an amino acid sequence having at least 70% identity to human ABri23 (SEQ ID NO: 4) ). In a preferred embodiment, the isolated protein according to the present invention is useful for the treatment of Alzheimer's disease.

  In one embodiment, an isolated protein for use according to the invention comprises a protein comprising an amino acid sequence having at least 70% identity to residues 90-236 of Bri2 from human (SEQ ID NO: 2) And a protein comprising an amino acid sequence having at least 70% identity to the Brichos domain of Bri2 from human (SEQ ID NO: 5).

  In certain embodiments, the isolated protein for use according to the invention is human (SEQ ID NO: 5), chimpanzee (SEQ ID NO: 6), bovine (SEQ ID NO: 7), pig (SEQ ID NO: 8), mouse (SEQ ID NO: 8). No. 9) and selected from the group consisting of proteins comprising an amino acid sequence having at least 90% identity to the Brichos domain of Bri2 from rat (SEQ ID NO: 10). In certain embodiments, the isolated protein for use according to the present invention is human (SEQ ID NO: 5), chimpanzee (SEQ ID NO: 6), bovine (SEQ ID NO: 7), pig (SEQ ID NO: 8), mouse ( Selected from the group consisting of proteins comprising any one of the Brichos domains of Bri2 from SEQ ID NO: 9) and rat (SEQ ID NO: 10).

  In certain embodiments, an isolated protein for use according to the present invention consists of amino acid residues less than or equal to 200, such as less than or equal to 150. In certain embodiments, an isolated protein for use in accordance with the present invention consists of more than 90 amino acid residues.

  According to a related aspect, the present invention produces a medicament for the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans. There is provided the use of an isolated protein according to the present invention to do so. In a preferred embodiment, the condition is Alzhiber disease.

  According to a related aspect, the present invention provides a pharmaceutical composition comprising a therapeutically effective amount of an isolated protein according to the present invention and a suitable pharmaceutical carrier for them. The pharmaceutical composition is particularly useful as a medicament in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia, in mammals including humans. In a preferred embodiment, the pharmaceutical composition according to the invention is useful for the treatment of Alzheimer's disease.

  According to another aspect, the present invention treats a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in a mammal, including a human in need thereof. A method is provided comprising administering to said mammal a therapeutically effective amount of an isolated protein according to the present invention or a pharmaceutical composition according to the present invention. In a preferred embodiment, the condition is Alzheimer's disease.

  In one embodiment, the treatment is selected from the group consisting of prophylactic, palliative and curative treatment.

[List of attached sequences]
SEQ ID NO: 1 human Bri2
SEQ ID NO: 2 human Bri2 (90-236)
SEQ ID NO: 3 human Bri2 (1-89)
Sequence number 4 Human ABri23 [Bri2 (244-266)]
SEQ ID NO: 5 Human Bri2 _Brichos [Bri2 (137-231)]
SEQ ID NO: 6 Chimpanzee Bri2 _Brichos
SEQ ID NO: 7 Bovine Bri2 _Briochos
SEQ ID NO: 8 Pig Bri2 _Briochos
SEQ ID NO: 9 Mouse Bri2 _Briochos
SEQ ID NO: 10 Rat Bri2 _Briochos
SEQ ID NO: 11 human Aβ _1-40 peptide SEQ ID NO: 12 human Aβ _1-42 peptide SEQ ID NO: 13 forward PCR primer SEQ ID NO: 14 reverse PCR primer SEQ ID NO: 15 synthetic peptide

Detailed Description of the Invention

  Bri2 (SEQ ID NO: 1) (also called integral membrane protein 2B (ITM2B)) contains an evolutionarily conserved Brichos domain spanning residues 137-231 (SEQ ID NO: 5). Brichos domains have been found in more than 10 different protein families that are functionally unrelated and expressed in different tissues. The name Brichos refers to the identification of domains in Bri, chondromodulin-1 associated with chondrosarcoma, and pulmonary surfactant protein C precursor (proSP-C) involved in respiratory disease. All of the Brichos-containing proteins identified thus far are type II membrane proteins, and the Brichos domain is located in the C-terminal, ER lumenal region.

  Surprisingly, it has been found that proteins containing the Brichos domain of mammalian Bri2 (ITM2B) and structurally similar proteins have the ability to reduce amyloid fibril formation and aggregation of Aβ-peptides and ABri / ADan peptides. It was issued.

  The present invention provides isolated proteins that are useful as pharmaceuticals. The isolated protein is useful for the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans. In a preferred embodiment, the isolated protein is useful for the treatment of Alzheimer's disease. The treatment may be prophylactic, palliative or curative treatment.

  According to a first aspect, the present invention relates to residues 90-236 of human-derived Bri2 (SEQ ID NO: 2); and human (SEQ ID NO: 5), chimpanzee (SEQ ID NO: 6), bovine (SEQ ID NO: 7), Provided is an isolated protein selected from the group of proteins consisting of the Brichos domain of Bri2 from pig (SEQ ID NO: 8), mouse (SEQ ID NO: 9) and rat (SEQ ID NO: 10). In certain embodiments, the isolated protein is selected from the group of proteins consisting of residues 90-236 of Bri2 from human (SEQ ID NO: 2); and the Brichos domain of Bri2 from human (SEQ ID NO: 5) Is done. In certain embodiments, the isolated protein consists of residues 90-236 of Bri2 from human (SEQ ID NO: 2) or the Brichos domain of Bri2 from human (SEQ ID NO: 5).

  The invention, according to another aspect, comprises a protein comprising an amino acid sequence having at least 70% identity to residues 90-236 of human-derived Bri2 (SEQ ID NO: 2); and human (SEQ ID NO: 5), chimpanzee (SEQ ID NO: 6), bovine (SEQ ID NO: 7), pig (SEQ ID NO: 8), mouse (SEQ ID NO: 9) and rat (SEQ ID NO: 10) from at least 70% relative to any one of Bri2's Brichos domains An isolated protein selected from the group consisting of proteins comprising amino acid sequences having the same identity is provided.

  As used throughout the specification and claims, the term “% identity” is calculated as follows: Query sequence is converted to target sequence using CLUSTAL W algorithm (Thompson, JD, Higgins, DG and Gibson, TJ, Nucleic Acid Research, 22: 4673-4680 (1994)). Align with each other. A comparison is made over the window corresponding to the shortest of the aligned sequences. The amino acid residues at each position are compared and the percentage of locations in the query sequence that have the same correspondence in the target sequence is reported as% identity.

  As used throughout the specification and claims, the term “% similarity” is similar to the hydrophobic residues Ala, Val, Phe, Pro, Leu, IIe, Trp, Met and Cys; The basic residues Lys, Arg and His are similar; the acidic residues Glu and Asp are similar; the hydrophilic uncharged residues Gln, Asn, Ser, Thr and Tyr are similar Except as calculated for “% identity”. The remaining natural amino acid Gly is not similar to any other amino acid in this context.

  Throughout this description, alternative embodiments according to the present invention satisfy the corresponding percentage of similarity instead of a specific percentage of identity. Other alternative embodiments meet a particular percentage of identity and another higher percentage of similarity selected from the group of preferred percentages of identity for each sequence. For example, an isolated protein sequence may be 70% similar to another protein sequence; or it may be 70% identical to another sequence; or it may be another sequence May be 70% identical and even 90% similar.

  For the avoidance of doubt, the amino acid sequence having at least a given identity to any one of residues 90-236 of Bri2 from human or the Brichos domain of Bri2 is greater than or equal to 70, for example, Consists of amino acid residues greater than or equal to 80, for example greater than or equal to 90. A preferred size range is 70-100 amino acid residues, such as 80-100 amino acid residues, for example 90-100 amino acid residues.

  The Brichos domain of Bri2 from human (SEQ ID NO: 5), chimpanzee (SEQ ID NO: 6), bovine (SEQ ID NO: 7), pig (SEQ ID NO: 8), mouse (SEQ ID NO: 9) and rat (SEQ ID NO: 10) is highly Note that the alignment in FIG. 2 is noted. Without wishing to be bound by any particular theory, it is believed that the Brichos domain has the desired activity with respect to Aβ and ABri / ADan peptides. Isolated proteins according to the present invention are human (SEQ ID NO: 5), chimpanzee (SEQ ID NO: 6), bovine (SEQ ID NO: 7), pig (SEQ ID NO: 8), mouse (SEQ ID NO: 9) and rat (SEQ ID NO: 10). Preferably, it is selected from the group consisting of proteins comprising amino acid sequences having at least 80%, preferably at least 90%, for example at least 95% identity to any one of the Brichos domains of Bri2 derived from . In a preferred embodiment, the isolated protein according to the invention is human (SEQ ID NO: 5), chimpanzee (SEQ ID NO: 6), bovine (SEQ ID NO: 7), pig (SEQ ID NO: 8), mouse (SEQ ID NO: 9) and All amino acid residues conserved in the Brichos domain of Bri2 from rat (SEQ ID NO: 10), ie, residues 42, 76 and 82 (full length Bri2, corresponding to residues 178, 212 and 218 of SEQ ID NO: 1) All of the amino acid residues of SEQ ID NO: 5. In certain embodiments, the isolated protein according to the invention is human (SEQ ID NO: 5), chimpanzee (SEQ ID NO: 6), bovine (SEQ ID NO: 7), pig (SEQ ID NO: 8), mouse (SEQ ID NO: 9). And a protein comprising any one of Bri2's Brichos domains from rat (SEQ ID NO: 10), ie, it is one of these Brichos domains, preferably one of the human Brichos domains (SEQ ID NO: 5) including.

  In contrast to the prior teaching, the isolated protein according to the present invention does not comprise an amino acid sequence having at least 70% identity to residues 1 to 89 (SEQ ID NO: 3) of Bri2 from human. In certain embodiments, an isolated protein according to the invention does not comprise an amino acid sequence having at least 50% identity to residues 1-89 of Bri2 from human. This is because the isolated protein according to the present invention shows a high similarity or identity to residues 90-236 of Bri2 from human (SEQ ID NO: 2) and / or (SEQ ID NO: 5 10) the mammalian Bri2 Brichos domain from 10) and optionally one or more other amino acid sequences (other amino acid sequences are highly similar to residues 1-89 of human-derived Bri2 (SEQ ID NO: 3)) Or may not exhibit gender or identity).

  For the avoidance of doubt, amino acid sequences shorter than 10 amino acid residues are considered irrelevant because they are excluded from the isolated protein according to the invention. Thus, an isolated protein according to the invention is an amino acid consisting of more than 10 amino acid residues having at least a given identity to residues 1 to 89 (SEQ ID NO: 3) of Bri2 from humans Does not contain an array.

  Furthermore, the isolated protein according to the invention does not contain amino acid sequences having at least 70% identity to residues 244 to 266 of human-derived Bri2, ie human ABri23 (SEQ ID NO: 4). In certain embodiments, an isolated protein according to the present invention does not comprise an amino acid sequence having at least 50% identity to the residue human ABri23 (SEQ ID NO: 4). As indicated above, this is a core amino acid sequence in which the isolated protein according to the present invention shows a high similarity or identity to residues 90-236 (Seq ID No. 2) of Bri2 from human And / or the mammalian Brichos domain of Bri2 from (SEQ ID NO: 5-10) and optionally one or more other amino acid sequences (this other amino acid sequence is highly similar to human ABri23 (SEQ ID NO: 4)) Or may not exhibit gender or identity).

  For the avoidance of doubt, amino acid sequences shorter than 10 amino acid residues are considered irrelevant because they are excluded from the isolated protein according to the invention. Thus, an isolated protein according to the present invention does not include an amino acid sequence consisting of more than 10 or equal amino acid residues having at least a given identity to human ABri23 (SEQ ID NO: 4).

  In a preferred embodiment, an isolated protein for use in accordance with the present invention comprises a protein comprising an amino acid sequence having at least 70% identity to residues 90-236 of Bri2 from human (SEQ ID NO: 2) And a protein comprising an amino acid sequence having at least 70% identity to the Brichos domain of Bri2 from human (SEQ ID NO: 5).

  A protein comprising a core amino acid sequence having one or more identities with the Bri2 target sequence as indicated above is an addition that does not interfere with the function of the core amino acid sequence, ie, the interaction with Aβ and ABri / ADan proteins The amino acid sequence may further be included. The additional amino acid sequence may be linked to the N-terminus of the core amino acid sequence, to the C-terminus of the core amino acid sequence, or both. It may be linked via an amino acid side chain, for example via a disulfide bond. Additional amino acid sequences may be non-functional in nature, but may confer additional functionality to the resulting protein, such as solubility, stability, or desired affinity. Both the core amino acid sequence and any additional amino acid sequences may be chemically modified, including post-translational chemical modifications.

  In one embodiment, the isolated protein according to the present invention is selected from the group of proteins consisting of the amino acid sequences having the identity shown above. That is, the isolated protein consists of the desired core amino acid sequence having one or more identities with the Bri2 target sequence as shown above. The core amino acid sequence may be chemically modified, including post-translational chemical modifications.

  In certain embodiments, an isolated protein according to the invention is less than or equal to 500, such as less than or equal to 250, such as less than or equal to 200, such as less than or equal to 150, or even It consists of 100 amino acid residues. In certain embodiments, an isolated protein according to the invention consists of amino acid residues that are greater than or equal to 80, such as greater than or equal to 90, such as greater than or equal to 100. A preferred size range is 80-200 amino acid residues, for example 90-150 amino acid residues, for example 90-100 amino acid residues.

It has been experimentally shown herein that recombinant human Bri2 (90-236) binds to ABri23. None of the region of Bri2 (90-236) that binds to the ABri23 peptide is known. Without wishing to be bound by any particular theory, it is believed that it is the Brichos domain in Bri2 (which is encompassed by Bri2 (90-236)) that mediates binding to ABri23. It is interesting to note that ABri23 has a high β-strand propensity. Since all but one of the known Brichos domains is followed by a C-terminal peptide segment with a high β-strand propensity, the Brichos domain can bind to a peptide segment with a high β-strand propensity. Binding of the non-cleavable region corresponding to ABri23 to the Brichos domain in full-length Bri2 is likely to facilitate the formation of a disulfide bridge between two Cys in ABri23 compared to the formation of disulfide in free ABri23 . If so, the Brichos domain of Bri2 functions as a chaperone that facilitates the correct folding of another part of the same proprotein. The substrate specificity of Bri2 (90-236) is unique in that it does not bind to any of the tripeptides composed exclusively of hydrophobic residues under gas phase conditions. The three long peptides to which Bri2 (90-136) binds have a particular motif in common (see Table 1). Both ABri23 and Aβ _1-40 contain an internal segment similar to the KFFEYNGKKFFE (SEQ ID NO: 15) segment by flanking hydrophobic residues with charged residues.

The ability of Bri2 (90-236) to bind to Aβ _1-40 is interesting because Bri2 was involved in binding to Aβ and APP processing. With regard to binding to Aβ, it has been suggested that ABri23 can bind to Aβ as such and prevent its aggregation (Kim et al., J. Neurosci. 28: 6030-6036 (2008)). When electrospray mass spectrometry was used, no binding between ABri23 and Aβ could be detected, but Bri2 (90-236) was clearly found to bind to Aβ _1-40 . In addition, Bri2 (90-236) reduces Aβ _1-40 aggregation and fibril formation even in substoichiometric amounts. It is noted that both Bri2 and Aβ are expressed in neural tissue and they can interact in vivo.

Recently, Bri2 affects the proteolytic processing of APP to Aβ, but it has been shown that Bri2 itself needs to be proteolytically processed before it can interfere with APP processing (Matsuda et al. Neurobiol Aging. (2009), doi: 10.016 / j.neurobiolaging. 2009.08.005). Current results provide a possible explanation for these findings. Both ABri23 and Aβ _1-40 bind to Bri2 (90-236), but clearly ABri23 binds more strongly. Although not wishing to be bound by any particular scientific theory, we do that in Bri2, the ABri23 region binds to the Brichos domain, which prevents the interaction between Bri2 and APP. I recommend that. Proteolytic release of the ABri23 peptide creates an empty Bri2 binding pocket for binding to the Aβ region of APP. Binding of Bri2 to the Aβ region of APP is likely to reduce its processing by secretase.

  According to another aspect, the present invention provides a pharmaceutical composition comprising a therapeutically effective amount of an isolated protein according to the present invention and a suitable pharmaceutical carrier for them. The pharmaceutical composition is useful as a pharmaceutical product. The pharmaceutical composition is useful for the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals including humans. In particular, the pharmaceutical composition is useful for the treatment of Alzheimer's disease in mammals including humans.

  According to a related aspect, the present invention produces a medicament for the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans. There is provided the use of an isolated protein according to the present invention to do so. In a preferred embodiment, the condition is Alzheimer's disease.

  Isolated proteins according to the present invention can be incorporated into pharmaceutical compositions. Such compositions typically comprise an isolated protein according to the present invention and a suitable pharmaceutically acceptable carrier. As used herein, “suitable pharmaceutical carriers” include solvents, dispersion media, coatings, isotonic and absorption delaying agents that are compatible with pharmaceutical administration. Supplementary active compounds can also be incorporated into the compositions.

  A pharmaceutical composition is formulated to be compatible with its intended route of administration. Examples of routes of administration include parenteral (eg, intravenous, intradermal, subcutaneous), oral, intranasal (eg, inhalation), transdermal, transmucosal, intrathecal, intraventricular (eg, the cisterna magna) In-line filtered Omaya reservoir shunts surgically placed in space), and rectal administration.

  Potentially useful parenteral delivery systems for the composition include slowly dissolving polymer particles, implantable infusion systems, and liposomes. Solutions or suspensions used for parenteral use include the following ingredients: sterile diluent (water for injection, etc.), saline, fixed oil, polyethylene glycol, glycerin, propylene glycol or other synthetic solvents; antibacterial agents ( Benzyl alcohol or methyl paraben); antioxidants (such as ascorbic acid or sodium bisulfite); chelating agents (such as ethylenediaminetetraacetic acid); buffers (such as acetate, citrate or phosphate) and osmotic pressure regulators (Such as sodium chloride or dextrose). The pH can be adjusted with acids or bases, such as hydrochloric acid or sodium hydroxide. The parenteral preparation can be enclosed in ampoules, disposable syringes or multiple dose vials made of glass or plastic.

  Treatment of conditions of Alzheimer's disease, familial Danish dementia and familial British dementia can also be performed by direct delivery of the isolated protein according to the present invention to the central nervous system, preferentially the brain.

  Pharmaceutical compositions suitable for injectable use include sterile aqueous solutions (where water soluble) or dispersions and sterile powders for the extemporaneous preparation of sterile injectables or dispersions. For intravenous administration, suitable carriers include physiological saline, bacteriostatic water, Cremophor EL ™ or phosphate buffered saline (PBS). In all cases, the composition must be sterile and must be fluid to the extent that easy syringability exists. It should be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacteria and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (for example, glycerol, propylene glycol, and liquid polyethylene glycol, and the like), and suitable mixtures thereof. The proper fluidity is maintained, for example, by coating the isolated protein particles onto the particles (eg lecithin) according to the invention, by maintaining the required particle size in the case of dispersion and using a surfactant. Can be done. Prevention of the action of microorganisms can be achieved by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, ascorbic acid, thimerosal, and the like. In many cases, it will be preferable to include isotonic agents in the composition. Examples of such agents include sugars, polyhydric alcohols (such as mannitol and sorbitol), and sodium chloride. Prolonged absorption of injectable compositions can be brought about by including in the composition an agent that delays absorption, for example, aluminum monostearate or gelatin.

  Sterile injectables can be prepared by incorporating the isolated protein according to the invention in the required amount in a suitable solvent, optionally with one or a combination of the components listed above, followed by filter sterilization. . Generally, dispersions are prepared by incorporating the isolated protein according to the present invention into a sterile vehicle that contains a basic dispersion medium and other components required from those listed above. In the case of sterile powders for the preparation of sterile injectables, the preferred methods of preparation are vacuum drying and lyophilization, which are from the previously sterile filtered solution in addition to the isolated protein according to the invention. A powder consisting of additional desired ingredients is produced.

  Oral compositions generally include an inert diluent or an edible carrier. For oral therapeutic administration, the isolated protein according to the invention can be incorporated with excipients and used in the form of tablets, troches, or capsules, eg, gelatin capsules.

  Pharmaceutically compatible binding agents, and / or adjuvant materials can be included as part of the composition. Tablets, pills, capsules, lozenges, etc. can be any of the following components or compounds of similar nature, ie binders (such as microcrystalline cellulose, gum tragacanth or gelatin); excipients (such as starch or lactose) ); Disintegrant (such as arginic acid, Primogel, or corn starch); lubricant (such as magnesium stearate or Sterotes); glidant (such as colloidal silicon dioxide); sweetener (such as sucrose or saccharin); or aroma An agent (such as peppermint, methyl salicylate, or orange flavor) may be included.

  For administration by inhalation, the compounds are delivered in an aerosol spray form from a pressurized container or dispenser containing a suitable propellant, eg, carbon dioxide, or a nebulizer.

  Systemic administration can also be by transmucosal or transdermal means. For transmucosal or transdermal administration, penetrants appropriate to the barrier to be permeated are used in the formulation. Such penetrants are generally known in the art and include, for example, for transmucosal administration, surfactants, bile salts, and fusidic acid derivatives. Transmucosal administration can be accomplished through the use of nasal sprays or suppositories. For transdermal administration, the isolated protein according to the invention is formulated into ointments, salves, gels, or creams as is generally known in the art.

  Isolated proteins according to the invention can also be prepared in the form of suppositories (eg, with conventional suppository bases such as cocoa butter and other glycerides) or retention enemas for rectal delivery.

  In one embodiment, an isolated protein according to the present invention is prepared with a controlled release formulation comprising a carrier that protects the compound against rapid removal from the body, such as an implant and a microencapsulated delivery system. . Biodegradable, biocompatible polymers can be used, such as ethylene vinyl acetate, polyanhydrides, polyglycolic acid, collagen, polyorthoesters, and polylactic acid. Methods for preparing such formulations will be apparent to those skilled in the art. Liposomal suspensions (including liposomes targeted by monoclonal antibodies to cells specifically affected by Alzheimer's disease, familial Danish dementia or familial British dementia) are also used as pharmaceutically acceptable carriers. Can be used. These can be prepared according to methods known to those skilled in the art.

  It is advantageous to formulate oral or parenteral compositions in dosage unit form for ease of administration and uniformity of dosage. Dosage unit form as used herein refers to physically discrete units suitable as unit dosages for the subject being treated, each unit being associated with the desired pharmaceutical carrier and the desired treatment. Contains a predetermined amount of an isolated protein according to the present invention, calculated to produce an effect.

The toxic and therapeutic effects of isolated proteins according to the present invention determine, for example, LD ₅₀ (a lethal dose for 50% of the population) and ED ₅₀ (a therapeutically effective dose in 50% of the population). Can be determined by standard pharmaceutical procedures in cell cultures or laboratory animals. Suitable animal models such as, for example, Churchler-Pierrat et al., Rev Neurosci, 10: 15-24, 1999; Seabrook et al., Neuropharmacol 38: 1-17, 1999; DeArmond et al., Brain Pathology 5: 77-89. 1995; Telling, Neuropathol Appl Neurobiol 26: 209-220, 2000; and Price et al., Science 282: 1079-1083, 1998, can be used.

The dose ratio between toxic and therapeutic effects is the therapeutic index can be expressed as the ratio LD ₅₀ / ED _50. Compounds that exhibit high therapeutic indices are preferred. Compounds that exhibit toxic side effects can be used, but target such compounds to sites of affected tissue to minimize potential damage to unaffected cells and thereby reduce side effects Care should be taken to design the delivery system.

Data obtained from cell culture assays and animal studies can be used to formulate a series of doses for use in humans. Dose preferably compounds, without having little or no toxicity within a range of circulating concentrations that include the ED _50.

The dosage may vary within this range depending on the dosage form used and the route of administration used. For any compound used in the method of the invention, the therapeutically effective dose can be estimated initially from cell culture assays, for example, in which fibril formation or cell death is observed. The dose can be formulated in animal models to obtain a circulating plasma concentration range that includes the IC ₅₀ (ie, the concentration of the test compound that achieves half-maximal inhibition of symptoms) determined in cell culture. Such information can be used to more accurately determine useful doses in humans. The concentration in plasma can be measured, for example, by high performance liquid chromatography.

  As defined herein, a therapeutically effective amount (ie, effective dose) of an isolated protein according to the invention is about 0.1 to 100 mg / kg body weight, more preferably about 1 to 100 mg / kg. Body weight, even more preferably in the range of about 1 to 50 mg / kg body weight. The compound can be administered to the subject over an extended period of time, for example, over the lifetime of the subject. A dosage of 1 mg / kg to 100 mg / kg is usually appropriate, for example in the case of antibodies designated to act in the brain.

  In some cases, the compound is administered at a rate of about 1 to 10 weeks, preferably 2 to 8 weeks, more preferably about 3 to 7 weeks, and even more preferably about 4 to 5 or 6 weeks. Can be administered once. The compound can also be administered chronically. Certain factors, including but not limited to, the severity of the disease or disorder, previous treatment, the subject's general health and / or age, and the presence of other diseases are necessary to effectively treat the subject Those skilled in the art will appreciate that the dose and timing taken may be affected. Moreover, treatment of a subject with a therapeutically effective amount of a compound can include a single treatment or, preferably, can include a series of treatments.

  Recombinant isolated proteins according to the present invention comprising human Bri2 (90-236) and Bri2 Brichos domains for administration to mice or humans expressing human APP can be prepared in several ways. The recombinant protein can be purified as described in Example 1. Several methods are envisioned to increase the likelihood that the protein will cross the vascular brain barrier (BBB).

  Several major strategies have become apparent for drug passage through the BBB. They use an endogenous transport system by receptor-mediated transcytosis or with specific receptors for eg glucose, amino acids or peptides. Peptides are particularly attractive as vectors for carrying a variety of loads across the BBB. Many different peptides have been shown to cause endocytosis (typically via LDL-receptors) and to deliver cargo across the BBB. Some of these peptides are amphiphilic, positively charged cell penetrating peptides (CPPs such as penetratin, ApoE derived peptides, etc.), but they can also be highly toxic at high doses. Others such as the SynB family are also positively charged but have no hydrophobic moieties. A drawback with many of the endocytosis-triggered peptides is that they need to be relatively large to form a stable α-helix in order to be efficient, which correlates with efficient uptake. That seems to be. The advantage of delivery by transcytosis is that the load is very substantial and very variable. A route in which specific endogenous peptides that have been shown to cross the BBB by a saturated transport system act as vectors for drug delivery is also a viable alternative. Some such relatively short peptides, such as MIF-1 (Pro-Leu-Gly, derived from oxytocin) and Peptide T (8 residues, derived from the HIV envelope), efficiently transcend the BBB. Shown to be transported. For a description of methods for delivery across the BBB, see de Boer AG and Gaillard PJ, Clin Pharmacokitet. 46: 553-76, 2007; de Boer AG and Gaillard PJ, Annu Rev Pharmacol Toxicol. 47: 323-55, 2007; Pardridge WM, Drug Discov Today. 12: 54-61, 2007. In the current case, the peptide or protein can be mixed with human Bri2 (90-236) or Bri2 Brichos domain, or alternatively they can be covalently linked to human Bri2 (90-236) or Bri2 Brichos domain It is envisaged that it can be expressed.

  In other formulations, the human Bri2 (90-236) or Bri2 Brichos domain can be linked to nanoparticles for delivery across the BBB (Lockman PR, et al., Drug Dev Ind Pharm. 28: 1-13, 2002). Year; Tosi G et al., Expert Opin Drug Deliv. 5: 155-74, 2008).

  Modifications such as lipidation can also be used to stabilize proteins and enhance uptake and tissue penetration (eg, into the brain). Methods for lipidation of antibodies are described in Cruikshank et al., J Acquired Immunology Syndrome Hum Retrovirol 14: 193, 1997.

  When an isolated protein according to the present invention is administered to an animal (eg, human) to treat Alzheimer's disease, familial Danish dementia or familial British dementia, a physician, veterinarian, or research One will, for example, first formulate a relatively low dose and then increase the dose until a suitable response is obtained. Furthermore, the specific dose level for any particular animal subject is the activity of the particular compound used, the subject's age, weight, general health, sex, and diet, time of administration, route of administration, excretion rate, It will be understood that it depends on a variety of factors, including any drug combination and the degree of expression or activity to be modulated.

  The pharmaceutical composition of the invention can be included in a container, pack, or dispenser together with instructions for administration. For example, the instructions can include use of the composition to treat an individual having or at risk for Alzheimer's disease, familial Danish dementia or familial British dementia.

  According to another aspect, the present invention provides a method of treating Alzheimer's disease, familial Danish dementia or familial British dementia, including a human in need thereof, comprising a therapeutically effective amount Of the isolated protein according to the present invention or the pharmaceutical composition according to the present invention is provided to said mammal.

  In certain embodiments, the treatment may be a prophylactic treatment. In other specific embodiments, the treatment may be palliative treatment. In certain embodiments, the treatment may be a curative treatment.

  The present invention provides both prophylactic and therapeutic methods for treating subjects at risk for (or affected by) Alzheimer's disease, familial Danish dementia or familial British dementia. As used herein, the term “treatment” refers to the application or administration of an isolated protein according to the invention to a patient, or Alzheimer's disease, familial Danish dementia or familial British dementia, Defined as the application or administration of an isolated protein according to the present invention to an isolated tissue or cell line from a patient having a disease symptom or predisposition to a disease and predisposing to that disease, disease symptom or disease predisposition Cure, heal, alleviate, relieve, alter, treat, remedy, improve, improve, or improve It has a purpose to affect them.

  In one aspect, the invention relates to a disease or condition associated with fibril formation caused by Aβ peptide and / or ABri / ADan peptide by administering to the subject an isolated protein according to the invention that reduces aggregation of the polypeptide. A method of preventing (ie, reducing the risk of developing a disease or condition, or reducing the rate of appearance of symptoms associated therewith). A subject at risk of Alzheimer's disease, familial Danish dementia or familial British dementia can be identified, for example, by any suitable diagnostic or prognostic assay or combination thereof known in the art. Administration of a prophylactic agent can be performed prior to the manifestation of symptoms characteristic of the disease, such that the disease is prevented or, alternatively, delayed in its progression.

  The isolated protein according to the present invention provides a patient with a therapeutically effective dose to prevent, treat or ameliorate disorders including fibril formation associated with Alzheimer's disease, familial Danish dementia or familial British dementia. Can be administered. A therapeutically effective dose refers to that amount of a compound sufficient to result in amelioration of the symptoms of the disorder. The toxicity and therapeutic efficacy of such compounds can be determined by standard pharmaceutical procedures as described above.

  The protein according to the invention is expressed in gene vectors, for example in order to transfect cells in the nervous system, preferably in the brain, such that the isolated protein is expressed by these cells in the central nervous system, It is also contemplated that it can be administered by using a plasmid or virus. This is useful for the treatment of Alzheimer's disease, familial Danish dementia or familial British dementia.

  The invention will now be further illustrated by the following non-limiting examples.

Example 1 Expression and Purification of Recombinant Bri2 (90-236) cDNA corresponding to human Bri2 residues 90-236 (SEQ ID NO: 2) was converted to forward primer 5′-GGTGCCATGGGAATA-3 ′ (SEQ ID NO: 13) and reverse primer 5 Amplification was performed from PCR ready human brain cDNA library (Ambion) using '-CTCTAGAGGATCCCCT-3' (SEQ ID NO: 14) (both from DNA technology AIS, Aarhus, Danmark). After digestion with BamH1 and Nco1, the amplified cDNA is subjected to pET-encoding His _6- , thioredoxin-, and S-tags upstream of the insert for increased solubility and ease of purification by affinity chromatography. Subcloned into the 32c vector (Novagen, Madison, WI). After transformation into E. coli strain Origami (DE3) pLysS (Novagen, Madison, Wis.), The selected bacterial colonies were OD at 30 ° C. in Luria-Bertani (LB) medium containing 100 μg / ml ampicillin. _The culture was continued for 16 hours until ₆₀₀ reached 0.8. Protein expression was then induced by adding 0.25 mM isopropylthiogalactoside (IPTG) and the cells were left at 25 ° C. for 6 hours. Cells are then harvested by centrifugation at 5000-6000 g for 20 minutes, resuspended in 20 mM sodium phosphate buffer, pH 7.0 containing 5 mM imidazole, and stored at −80 ° C. until use. did.

The bacterial pellet was sonicated and then centrifuged at 6000 g for 30 minutes. The supernatant was filtered through a 0.2 μm filter and 3 ml of nickel-nitrotriacetic acid-agarose (Qiagen Ltd., West Sussex) equilibrated in 20 mM sodium phosphate buffer, pH 7.0 containing 5 mM imidazole. , UK) column. The column was washed with 5-50 mM imidazole until the OD at 280 nm of the eluate was almost zero. The fusion protein was then eluted with 100 mM imidazole in the same buffer, collected and dialyzed against 20 mM sodium phosphate buffer, pH 7.0. The His ₆ -and thioredoxin tags were removed by cleavage with thrombin (from bovine plasma, Merck, Germany) at an enzyme / protein weight ratio of 0.002, incubated at 20 ° C. for 2 hours, and on a Ni-column. Removed by passing again. The eluted target protein was analyzed by SDS-PAGE, natural gel electrophoresis, and circular dichroism (CD) spectroscopy. Far-UV CD spectroscopy was performed using a J-820 spectrophotometer (Jasco, Japan) with a protein concentration of 25 μM and an optical path length of 0.1 cm in 2 mM phosphate buffer (pH 7.0).

  The fragment corresponding to Bri2 positions 90-236 (SEQ ID NO: 2) was expressed as a soluble fusion protein together with hexahistidine, thioredoxin and S-tag in E. coli and purified by immobilized metal affinity chromatography. After cleavage with thrombin and removal of affinity and lytic tags, analyzed by SDS and native gel electrophoresis, approximately 30 mg S-tagged Bri2 (90-236) with> 90% purity per liter of bacterial culture. Was obtained (FIG. 3).

FIG. 3 shows SDS-PAGE (A) with and without reduction (+) and native gel electrophoresis of recombinantly expressed Bri2 (90-236) with dithiothreitol (DTT). As shown in FIG. 3, analysis of non-reduced Bri2 (90-236) shows that the major fraction of the protein is monomeric and the multipolymer type can be removed by reduction (+). This suggests that the two Cys residues of Bri2 (90-236) preferentially form intramolecular disulfide bonds. The CD spectrum of Bri2 (90-236) (FIG. 4) shows that the protein is mainly folded into an α-helix / disordered structure. This is in good agreement with the expected secondary structure of the same region, suggesting a predominantly irregular structure and nearly equal content of α-helix and β-sheet. In FIG. 4, the average molar residual axial ratio (θ) is expressed as kdeg × cm ² / dmol.

Example 2-Binding of peptides to Bri2 (90-236) examined by ESI-MS Prior to electrospray ionization mass spectrometry (ESI-MS), a spin column with a 3 kDa cutoff limit (Nanosep, Pall Corp., East) Hills, NY, USA) was used to rebuffer purified Bri2 (90-236) (SEQ ID NO: 2) in 10 mM ammonium acetate, pH 7.0. Proteins and peptides were mixed directly at 22 ° C. prior to analysis at a final protein concentration of 20 μm and a final peptide concentration of 50 μM. Data were acquired using a QTOF Ultimate API mass spectrometer (Waters, Milford, Mass., USA) equipped with a Z-spray source operating in positive ion mode. Samples were introduced by nanoelectrospray using a metal-plated borosilicate glass capillary needle (Proxeon, Denmark). The source temperature was 80 ° C., the capillary voltage was 1.7 kV, and the cone and RF lens 1 potentials were 100 and 38 V, respectively. The mass spectrometer was operated in single reflector mode at 10,000 resolution (full width half maximum resolution) and the mass scale was calibrated with myoglobin. The scan was acquired at a rate of 1 scan per 2 seconds between 500 and 4000 m / z. The impinging gas was 5.2 × 10 ⁻⁵ mbar argon. Mass spectra were smoothed using Waters MassLynx software.

All of the peptides were purchased from Thermo Electron (Darmstadt, Germany) with the exception of KFFEYNGKKFFE (SEQ ID NO: 15), ABri23 (SEQ ID NO: 4) and Aβ _1-40 (SEQ ID NO: 11). KFFEYNGKKFFE was purchased from Interactiva (Ulm, Germany), and Aβ _1-40 and disulfide-linked ABri23 were purchased from Bachem (Bubedorf, Switzerland).

The peptides were acetylated at the N-terminus and amidated at the C-terminus, with the exception of KFFEYNGKKFFE, ABri23 and Aβ _1-40 . All compositions of the peptides were verified by ESI-MS and amino acid analysis. Peptide YYY was dissolved to a final concentration of 10 mM in 30% acetonitrile. VVV, FFF and LLL were dissolved in 50% isopropanol to a final concentration of 10 mM. KKK, GGG and AAA were dissolved in water to a final concentration of 10 mM, while KFFEYNGKKFFE and ABri23 were dissolved to a final concentration of 5.6 mM and 1 mM in water, respectively. All peptide samples were stored at −20 ° C. with the exception of Aβ _1-40, which was dissolved directly to a final concentration of 1 mM in water prior to analysis.

ESI-MS binding experiments were performed to determine whether Bri2 (90-236) could bind to peptides ABri23 and Aβ _1-40 . To this end, Bri2 (90-236) is added to a final concentration of 20 μM Bri2 (90-236) and 50 μM of each peptide with ABri23, Aβ _1-40 , or an equimolar mixture of ABri23 and Aβ _1-40. Mixed and analyzed by ESI-MS. Mass spectra were recorded to investigate the presence and stoichiometry of protein-peptide complexes in the gas phase.

The ESI-MS spectrum of 20 μM recombinant Bri2 (90-236) without peptide shows a series of peaks at m / z 2040.6, 2267.3, and 2550.6, from a protein with a molecular mass of 20397 ± 2 Da The monomeric charge states of [M + 10H] ¹⁰⁺ , [M + 9H] ⁹⁺ and [M + 8H] ⁸⁺ were shown (FIG. 5A).

Addition of a 2.5-fold molar excess of oxidized ABri23 (50 μM; theoretical mass: 2627.9 Da) to Bri2 (90-236) protein (20 μM) resulted in [M + 10H] ¹⁰⁺ and [M + 9H] ⁹⁺ Bri2 (90- 236) 1: 1 Bri2 with a calculated monoisotopic mass of 23028.4 Da, resulting in an almost complete shift of the peaks to m / z 2303.4 and m / z 2559.4, divided by 10 or 9 charges, respectively This corresponds to the mass of (90-236) / ABri23 complex (FIG. 5B). Recombinant Bri2 (90-236) and ABri23 heteromers were observed with charges of 10, 9, and 8. Only a small amount of free recombinant Bri2 (90-236) was observed for the corresponding [M + 10H] ¹⁰⁺ , [M + 9H] ⁹⁺ and [M + 8H] ⁸⁺ charge states, and under the ESI-MS conditions recombinant Bri2 (90-236). 236) showed almost complete saturation with ABri23. The exact assignment of the Bri2 (90-236) / ABri23 complex was verified by collision-induced dissociation of the m / z 2303.4 ion, and Bri2 (90-90) with charges of 8, 9 and 10 at collision voltages exceeding 40 eV. 236) and dissociated into ABri23 having 1 or 2 charges.

Similarly, a 2.5-fold excess addition of freshly dissolved Aβ _1-40 (50 μM; theoretical mass 4328.8 Da) to Bri2 (90-236) protein (20 μM) resulted in a charge of 9 and 10, respectively. This resulted in the appearance of peaks at m / z 2750.0 and m / z 2475.0, corresponding to a 1: 1 complex of Bri2 (90-236) and Aβ _1-40 (FIG. 5C). Only a small amount of recombinant Bri2 (90-236) / Aβ _1-40 complex was observed for [M + 10H] ¹⁰⁺ and [M + 9H] ⁹⁺ charge states. In the Bri2 (90-236) / ABri23 complex, collision-induced dissociation of the m / z 2475.0 ion leads to Bri2 (90-236) with 9 and 10 charges, and Aβ _1-40 with 3 charges. This resulted in dissociation of the complex (data not shown).

The addition of ABri23 resulted in almost complete saturation of Bri2 (90-236) with ABri23, but the addition of Aβ _1-40 at the same protein / peptide ratio was only a few in the complex with Aβ _1-40. Only resulted in the formation of Bri2 (90-236) (FIGS. 5B and C). Competition experiments with both peptides present in equimolar amounts supported this observation and there was visible formation of the Bri2 (90-236) / ABri23 complex, but Bri2 (90-236) / Aβ _{1− The} signal corresponding to the ₄₀ complex was only minor (FIG. 5D). FIG. 5D shows the ESI-MS spectrum of 20 μM recombinant Bri2 (90-236) in the presence of 50 μM Aβ _1-40 and ABri23. Almost all detectable recombinant Bri2 (90-236) has a small peak corresponding to recombinant Bri2 (90-236) in complex with Aβ _1-40 , despite being complexed with ABri23. [M + 10H] ¹⁰⁺ charge states can be observed. This suggests that Bri2 (90-236) binds preferentially to ABri23, or that the Bri2 (90-236) / ABri23 complex is more stable under the conditions used for mass spectroscopy. To do.

To further investigate the substrate specificity of Bri2 (90-236), it has aromatic (YYY, FFF), hydrophobic (VVV, LLL), charged (KKK) or small uncharged (AAA, GGG) side chains Binding was tested using homotripeptides while maintaining water solubility. FIG. 6 shows the ESI-MS spectrum of 20 μM recombinant Bri2 (90-236) in the presence of 50 μM of various peptides. The peptide sequence is shown in each spectrum. The symbols ^* and ^** indicate peaks corresponding to recombinant Bri2 (90-236) with one or two peptide ligands, respectively. No interaction was observed for FFF, VVV, LLL, KKK, AAA, or GGG at a peptide / protein ratio of 2.5. Only YYY and KFFEYNGKKFFE were found to form a complex with recombinant Bri2 (90-236) under ESI-MS conditions. In the case of YYY, a peak corresponding to a complex of Bri2 (90-236) and one or two YYY molecules is observed (FIG. 6), and Bri2 (90-236) interacts with this tripeptide in the gas phase. Indicates that it can act. Bri2 (90-236) also binds to the peptide KFFENYGKKFFE (FIG. 6).

Example 3 Effect of Bri2 (90-233) on Aβ _1-40 Aggregation and Fibril Formation 25 μM Aβ _1-40 (SEQ ID NO: 11) was converted to 1: 1, 2: 1, or 10: 1 Aβ / Bri2 (90-236) molar ratio for 48 hours at 37 ° C. with or without recombinant Bri2 (90-236) (SEQ ID NO: 2) in 20 mM phosphate buffer, pH 7.0 with 200 rpm agitation Incubated. Aβ _1-40 was dissolved in 250 μM stock solution with 100% DMSO and diluted to working concentration. For thioflavin (ThT) fluorescence measurements, 10 μl aliquots are removed at different time points, 10 μM ThT (Aldrich) is added, and measured with a FarCyte fluorescence plate reader (GE Healthcare) (emission wavelength is 480 nm, excitation wavelength is 440 nm) did. ThT was measured in two ways.

For analysis of soluble Aβ _1-40 and Aβ aggregate ultrastructures, aliquots were removed and centrifuged at 3300 g for 9 minutes. The supernatant was analyzed by SDS-PAGE, the pellet was resuspended in 200 μl of distilled water, 2 μl of suspension was added onto a 200 mesh copper electron microscope grid and stained with 2% uranyl acetate for 30 seconds, then Allowed to dry at 20 ° C. A Hitachi H7100 microscope operated at 75 kV was used for inspection and photography.

In the absence of Bri2 (90-236), Aβ _1-40 begins to form β-sheet rich aggregates after 7 hours, as judged by ThT fluorescence. However, when incubated with Bri2 (90-236), no ThT positive aggregates were seen within the 24 hours tested, regardless of the Aβ _1-40 / Bri2 (90-236) ratio. FIG. 7 shows the ThT fluorescence of Aβ _1-40 alone (solid line) and mixed with recombinant Bri (90-236) in ratios of 1: 1, 2: 1, and 10: 1 (dotted line and dashed line). .

Similarly, co-incubation with Bri2 (90-236) was observed for Aβ that remained in solution even after 3 weeks of incubation, as judged by SDS-PAGE of the supernatant obtained by centrifugation at 3300 g. Brought _1-40 . FIG. 8 shows time zero (left gel) and mixed alone (lane 1) or with recombinant Bri2 (90-236) in ratios of 1: 1, 2: 1, and 10: 1 (lane 2). -4) SDS-PAGE of the supernatant obtained after 5 days of incubation at 37 ° C. with 25 μM Aβ _1-40 (right gel).

Electron microscopy of the pellet formed after 5 days shows that Aβ _1-40 formed amyloid-like fibrils and that co-incubation with Bri2 (90-236) produces lower amounts of fibrils. It was. FIG. 9 shows the appearance of Aβ _1-40 incubated alone (A) or recombinant Bri2 (90-236) at a 1: 1 molar ratio for 5 days (B). Also shown is recombinant Bri2 (90-236) incubated alone (C). The scale bar represents 100 μm in A and 50 μm in B and C.

Example 4- Effect of Bri2 (90-236) on fibril formation of Aβ _1-40 and Aβ _1-42 Aβ _1-40 (SEQ ID NO: 11) and Aβ _1-42 (SEQ ID NO: 12) were synthesized from synthetic genes in E. coli. In Walsh et al., FEBS J. et al. Purified in batch format using ion exchange and size exclusion steps as described in 2009, 276, 1266-1281. The purified peptide was divided into 20-30 identical aliquots and frozen. The monomer was then purified peptide immediately before starting each experiment described below to remove traces of aggregates formed during freezing and thawing and to replace the buffer with that used in each experiment. Isolated by gel filtration. Monomers were collected on ice in low binding Ep tubes (Axygene) and concentrations determined by absorbance or amino acid analysis after acid hydrolysis. Monomers were used as such or diluted to the desired concentration for each experiment. Bri2 (90-236) (SEQ ID NO: 2) was expressed and purified as described in Example 1.

Aggregation kinetics were tested by recording the fluorescence intensity of thioflavin T (ThT) as a function of time on a plate reader (BMG Labtech, Offenberg, Germany FluoStar Omega). Fluorescence was recorded using bottom optics in a 96 well half area PEG coated black polystyrene plate (Corning 3881) with a transparent bottom using a 440 nm excitation filter and a 480 nm emission filter. Aβ monomer is 20 mM Na-phosphate, 200 μM EDTA, 0.02% NaN ₃ (pH 7.4 for Aβ _1-40 and pH 8.0 for Aβ _1-42 ), and the same Dilute to 6 or 8 μM for Aβ _1-40 in buffer and 3 μM for Aβ _1-42 and supplement with 20 μM ThT from 2 mM stock and isolated by gel filtration as described above. .

  Each well in a 96 well plate contains 10 μl of buffer (20 mM Tris / HCl pH 7.4) or 10 times the concentration of Bri2 (90-236) protein in the final concentration of 20 mM Tris / HCl pH 7.4 or Either 10 μl of control protein was added. 90 μl of ice-cold Aβ monomer solution is then added to each well and the plate is immediately placed in a plate reader at 37 ° C. and fluorescence is read every 6 minutes with continuous shaking at 100 rpm between readings. It was.

Aβ _1-40 was tested alone or together with Bri2 (90-236) at concentrations ranging from 60 nM to 6 μM. Aβ _1-42 was tested alone or in conjunction with Bri2 (90-236) at concentrations ranging from 20 nM to 6 μM.

ThT was used as a reporter for fibril formation in kinetic experiments monitoring ThT fluorescence as a function of time for Aβ alone or Aβ with different concentrations of Bri2 (90-236) protein. Examples of aggregation kinetics for Aβ _1-40 alone and with 0.01 or 0.03 molar equivalents of Bri2 (90-236) are shown in FIGS. 10A-C, respectively. Clearly, the lag time for Aβ _1-40 aggregation increases extensively in the presence of Bri2 (90-236), but the elongation rate is not significantly affected. A very large effect on lag time is observed at concentrations much lower than the equimolar concentration of Bri2 (90-236) relative to Aβ _1-40 . An intermediate point in the aggregation process, t1 _{/ 2,} was obtained from each kinetic trace by fitting a sigmoid function to the data. Half-time increased from 9.0 ± 0.6 hours for 6 μM Aβ _1-40 alone to 14.2 ± 0.2 for 6 μM Aβ with 60 nM Bri2 (90-236). In the presence of 170 nM Bri2 (90-236), the half time was extended approximately 4.5 times to 40.5 ± 2.0 hours. The delayed effect increases with increasing Bri2-Brichos concentration, and when the molar ratio exceeds 0.1 (1 Bri2 (90-236) per 10 Aβ _1-40 molecules), the lag time is 1 week It becomes difficult to actually quantify.

Examples of kinetic tracking by ThT fluorescence for Aβ _1-42 alone and with 0.05 and 0.1 molar equivalents of Bri2 (90-236) are shown in FIGS. Bri2 (90-236) delays aggregation of Aβ _{1-42 in} less than equimolar amounts of Bri2 (90-236) protein. At a molar ratio of 0.1 (1 Bri2 (90-236) per 10 Aβ _1-42 ), the lag time and half time double as compared to the undisturbed case, but the extension rate is The same is true in all cases. Although a strong effect is seen for Aβ _1-42 aggregation kinetics, it is clear that higher concentrations of Bri2 (90-236) protein are required to exert the same effect on Aβ _1-40 aggregation It is.

A control experiment was set up to test the aggregation kinetics of Aβ _1-40 and Aβ _1-42 in the presence of three proteins (antithrombin, cystatin and single chain monelin mutant). Each control protein was added at 0.1 and 1 molar equivalent to Aβ _1-40 and Aβ _1-42 , and aggregation was followed by the ThT assay. In all cases, the effect observed for Aβ aggregation was small compared to that seen for the same amount of Bri2 (90-236) (data not shown).

Aggregation of 8 μM Aβ _1-40 gave ThT fluorescence intensity as a function of time in 37 ° C., 20 mM Na-phosphate, 200 μM EDTA, 20 μM ThT, 0.02% NaN ₃ with 100 rpm shaking. Monitored by recording. Before the start of the experiment or at different time points ranging from 0.3 to 11.2 hours after the start of the experiment, 800 nM Bri2 (90-236) was added from the concentrated stock solution. Clearly, the aggregation process can be delayed by Bri2 (90-236) protein, even if added somewhere during the lag time. When Bri2 (90-236) is added during the early part of the sigmoid transition, the process appears to stop without further growth of the ThT positive aggregation. When added close to the midpoint of the transition, the Bri2 (90-236) protein causes the process to decrease its speed and proceed at a lower rate. If added at the end of the transition, no effect is seen.

The figure which shows the schematic of Bri2 (sequence number 1) processing. The figure which shows the alignment of Bri2-Brichos amino acid sequence (sequence number 5-10) of some mammals. Natural gel electrophoresis (B) of (+) and without (−) SDS-PAGE (A) with reduction by dithiothreitol (DTT) and Bri2 (90-236) (SEQ ID NO: 2) expressed recombinantly FIG. The figure which shows CD spectrum of recombinant Bri2 (90-236) (sequence number 2). Recombinant Bri2 (90-236) (SEQ ID NO: 2), Aβ _1-40 (SEQ ID NO: 11) (C), and ABri23 and Aβ ₁ alone (A) and in the presence (B) of ABri23 (SEQ ID NO: 4) _The figure which shows the ESI-MS spectrum of both (D) _-40 . The figure which shows the ESI-MS spectrum of recombinant Bri2 (90-236) (sequence number 2) in presence of various peptides containing sequence number 15. Figure 2 shows thioflavin T (ThT) fluorescence of Aβ _1-40 (SEQ ID NO: 11) alone (solid line) and mixed with recombinant Bri2 (90-236) (SEQ ID NO: 2) at different ratios (dotted line and dashed line). SDS of supernatants obtained at different time points (lanes 2-4) Aβ _1-40 (SEQ ID NO: 11) alone (lane 1) and mixed with recombinant Bri2 (90-236) (SEQ ID NO: 2) in different ratios -The figure which shows PAGE. Aβ _1-40 (SEQ ID NO: 11), recombinant Bri2 (90-236) (SEQ ID NO: 2) (C), or a combination of Aβ _1-40 and Bri2 (90-236) at a molar ratio of 1: 1 for 5 days The figure which shows the electron microscopic external appearance of (B). Bri2 (90-236) (SEQ ID NO:) for fibril formation of Aβ _1-40 (SEQ ID NO: 11) (AC) and Aβ _1-42 (SEQ ID NO: 12) (DF) in thioflavin T (ThT) fluorescence assay The figure which shows the effect of 2).

Aggregation of 8 μM Aβ _1-40 gave ThT fluorescence intensity as a function of time in 37 ° C., 20 mM Na-phosphate, 200 μM EDTA, 20 μM ThT, 0.02% NaN ₃ with 100 rpm shaking. Monitored by recording. Before the start of the experiment or at different time points ranging from 0.3 to 11.2 hours after the start of the experiment, 800 nM Bri2 (90-236) was added from the concentrated stock solution. Clearly, the aggregation process can be delayed by Bri2 (90-236) protein, even if added somewhere during the lag time. When Bri2 (90-236) is added during the early part of the sigmoid transition, the process appears to stop without further growth of the ThT positive aggregation. When added close to the midpoint of the transition, the Bri2 (90-236) protein causes the process to decrease its speed and proceed at a lower rate. If added at the end of the transition, no effect is seen.
Below, the claims at the beginning of the filing of the present application are appended as embodiments.
[1] Residues 90 to 236 of human-derived Bri2 (SEQ ID NO: 2), Bri2 domain of human-derived Bri2 (SEQ ID NO: 5), Brichos domain of chimpanzee-derived Bri2 (SEQ ID NO: 6), derived from bovine Bri2's Brichos domain (SEQ ID NO: 7), porcine-derived Bri2's Brichos domain (SEQ ID NO: 8), mouse-derived Bri2's Brichos domain (SEQ ID NO: 9) and rat-derived Bri2's Brichos domain (SEQ ID NO: 10) An isolated protein selected from the group of proteins.
[2] The isolated according to [1], selected from the group of proteins consisting of residues 90 to 236 of human-derived Bri2 (SEQ ID NO: 2) and the Brichos domain of human-derived Bri2 (SEQ ID NO: 5) Protein.
[3] The isolated protein according to [2], consisting of residues 90 to 236 (SEQ ID NO: 2) of Bri2 derived from human.
[4] The isolated protein according to [2], consisting of a Brichos domain (SEQ ID NO: 5) of Bri2 derived from human.
[5] The isolated protein according to any one of [1] to [4] for use as a pharmaceutical product.
[6] The isolation according to [5] for use in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals including humans. Protein.
[7] The isolated protein according to [6], wherein the condition is Alzheimer's disease.
[8] For producing a medicament for the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals including humans, [1] to [1] Use of the isolated protein according to any one of [4].
[9] The use according to [8], wherein the condition is Alzheimer's disease.
[10] A pharmaceutical composition comprising a therapeutically effective amount of the isolated protein of any one of [1] to [4] and a suitable pharmaceutical carrier for them.
[11] The pharmaceutical composition according to [10] for use as a pharmaceutical product.
[12] The pharmaceutical composition according to [11] for use in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals including humans object.
[13] The pharmaceutical composition for use according to [12], wherein the condition is Alzheimer's disease.
[14] Residue 90 of human-derived Bri2 for use in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans A protein comprising an amino acid sequence having at least 70% identity to ~ 236 (SEQ ID NO: 2); and a Bri2 domain of Bri2 from human (SEQ ID NO: 5), a Brichos domain of Bri2 from chimpanzee (SEQ ID NO: 6) ), The Brichos domain of Bri2 from bovine (SEQ ID NO: 7), the Brichos domain of Bri2 from pig (SEQ ID NO: 8), the Brichos domain of Bri2 from mouse (SEQ ID NO: 9) and the Brichos domain of Bri2 from rat (SEQ ID NO: 9) Any one of number 10) A protein comprising an amino acid sequence having at least 70% identity to said amino acid (provided that said protein is an amino acid having at least 70% identity to residues 1 to 89 of human-derived Bri2 (SEQ ID NO: 3)) An isolated protein selected from the group consisting of: no sequence, wherein the protein does not comprise an amino acid sequence having at least 70% identity to human ABri23 (SEQ ID NO: 4).
[15] a protein comprising an amino acid sequence having at least 70% identity to residues 90-236 of human-derived Bri2 (SEQ ID NO: 2); and against the Brichos domain of human-derived Bri2 (SEQ ID NO: 5) An isolated protein for use according to [14], selected from the group consisting of a protein comprising an amino acid sequence having at least 70% identity.
[16] Bri2's Brichos domain (SEQ ID NO: 5) derived from human, Bri2's Brichos domain (SEQ ID NO: 6) derived from chimpanzee, Bri2's Brichos domain (SEQ ID NO: 7) derived from bovine, Bricho's domain of Bri2 derived from pig (SEQ ID NO: 7) SEQ ID NO: 8), comprising an amino acid sequence having at least 90% identity to any one of the Brichos domain of Bri2 derived from mouse (SEQ ID NO: 9) and the Brichos domain of Bri2 derived from rat (SEQ ID NO: 10) An isolated protein for use according to any one of [14] to [15], selected from the group consisting of proteins.
[17] Bri2 domain of Bri2 derived from human (SEQ ID NO: 5), Brichos domain of Bri2 derived from chimpanzee (SEQ ID NO: 6), Brichos domain of Bri2 derived from bovine (SEQ ID NO: 7), Brichos domain of Bri2 derived from pig (SEQ ID NO: 7) SEQ ID NO: 8), selected from the group consisting of a protein comprising any one of the Brichos domain of Bri2 derived from mouse (SEQ ID NO: 9) and the Brichos domain of Bri2 derived from rat (SEQ ID NO: 10), [16] Isolated protein for use as described.
[18] An isolated protein for use according to any one of [14] to [17], consisting of 200 or fewer amino acid residues.
[19] The isolated protein for use according to [18], comprising no more than 150 amino acid residues.
[20] The isolated protein for use according to any one of [14] to [19], comprising 90 or more amino acid residues.
[21] The isolated protein for use according to any one of [14] to [20], wherein the condition is Alzheimer's disease.
[22] For the manufacture of a medicament for the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans [14]- [20] Use of the isolated protein according to any one of [20].
[23] The use according to [22], wherein the condition is Alzheimer's disease.
[24] A therapeutically effective amount for use in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans [14] A pharmaceutical composition comprising the isolated protein of any one of to [20] and a suitable pharmaceutical carrier for them.
[25] The pharmaceutical composition according to [24], wherein the condition is Alzheimer's disease.
[26] A method of treating a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans, in need of treatment, comprising: An effective amount of the isolated protein according to any one of [1] to [4] and [14] to [20] or the pharmaceutical composition according to any one of [10] and [24]. Administering to the mammal.
[27] The method according to [26], wherein the condition is Alzheimer's disease.
[28] The method of any one of [26] and [27], wherein the treatment is selected from the group consisting of prophylactic, palliative and curative treatment.

Claims (28)

  Residues 90 to 236 of human-derived Bri2 (SEQ ID NO: 2), Bri2 domain of human-derived Bri2 (SEQ ID NO: 5), Brichos domain of Bri2 derived from chimpanzee (SEQ ID NO: 6), Brichos of Bri2 derived from bovine A group of proteins consisting of a domain (SEQ ID NO: 7), a Bri2 Brichos domain (SEQ ID NO: 8) from porcine, a Bri2 Brichos domain (SEQ ID NO: 9) from mouse, and a Bri2 Brichos domain (SEQ ID NO: 10) from rat An isolated protein selected from.   2. The isolated protein of claim 1 selected from the group of proteins consisting of residues 90-236 of human-derived Bri2 (SEQ ID NO: 2) and the Brichos domain of human-derived Bri2 (SEQ ID NO: 5).   The isolated protein according to claim 2, consisting of residues 90 to 236 of human-derived Bri2 (SEQ ID NO: 2).   The isolated protein according to claim 2, which consists of the Brichos domain (SEQ ID NO: 5) of Bri2 derived from human.   The isolated protein according to any one of claims 1 to 4, for use as a medicament.   6. An isolated protein according to claim 5 for use in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans. .   7. The isolated protein of claim 6, wherein the condition is Alzheimer's disease.   Any of claims 1-4 for the manufacture of a medicament for the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans. Use of an isolated protein according to claim 1.   Use according to claim 8, wherein the condition is Alzheimer's disease.   A pharmaceutical composition comprising a therapeutically effective amount of the isolated protein of any one of claims 1 to 4 and a suitable pharmaceutical carrier therefor.   11. A pharmaceutical composition according to claim 10 for use as a medicament.   12. A pharmaceutical composition according to claim 11 for use in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals including humans.   13. A pharmaceutical composition for use according to claim 12, wherein the condition is Alzheimer's disease.   Residues 90-236 of human-derived Bri2 for use in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans ( A protein comprising an amino acid sequence having at least 70% identity to SEQ ID NO: 2); and a Bri2 domain of Bri2 from human (SEQ ID NO: 5), a Brichos domain of Bri2 from chimpanzee (SEQ ID NO: 6), bovine Brichos domain from Bri2 (SEQ ID NO: 7), Brichos domain from pig 2 (SEQ ID NO: 8), Brichos domain from Bri2 from mouse (SEQ ID NO: 9) and Brichos domain from rat Bri2 (SEQ ID NO: 10) For any one of A protein comprising an amino acid sequence having at least 70% identity (provided that said protein has an amino acid sequence having at least 70% identity to residues 1 to 89 (SEQ ID NO: 3) of Bri2 derived from human) An isolated protein selected from the group consisting of: and not comprising an amino acid sequence having at least 70% identity to human ABri23 (SEQ ID NO: 4).   A protein comprising an amino acid sequence having at least 70% identity to residues 90-236 of human-derived Bri2 (SEQ ID NO: 2); and at least 70 to the Brichos domain of human-derived Bri2 (SEQ ID NO: 5) 15. An isolated protein for use according to claim 14, selected from the group consisting of proteins comprising amino acid sequences having% identity.   Brichos domain of human derived Bri2 (SEQ ID NO: 5), Brichos domain of chimpanzee derived Bri2 (SEQ ID NO: 6), Brichos domain of bovine derived Bri2 (SEQ ID NO: 7), Brichos domain of Bri2 derived from pig (SEQ ID NO: 8) ), A protein comprising an amino acid sequence having at least 90% identity to any one of the Brichos domain of Bri2 (SEQ ID NO: 9) derived from mouse and the Brichos domain of Bri2 (SEQ ID NO: 10) derived from rat 16. Isolated protein for use according to any one of claims 14 to 15, selected from the group.   Brichos domain of human derived Bri2 (SEQ ID NO: 5), Brichos domain of chimpanzee derived Bri2 (SEQ ID NO: 6), Brichos domain of bovine derived Bri2 (SEQ ID NO: 7), Brichos domain of Bri2 derived from pig (SEQ ID NO: 8) ), A Brichos domain of Bri2 (SEQ ID NO: 9) from mouse, and a Brichos domain (SEQ ID NO: 10) of Bri2 from rat (SEQ ID NO: 10). Isolated protein for.   18. An isolated protein for use according to any one of claims 14 to 17 consisting of no more than 200 amino acid residues.   19. An isolated protein for use according to claim 18 consisting of no more than 150 amino acid residues.   20. An isolated protein for use according to any one of claims 14 to 19, consisting of 90 or more amino acid residues.   21. An isolated protein for use according to any one of claims 14 to 20, wherein the condition is Alzheimer's disease.   21. Any of claims 14-20 for the manufacture of a medicament for the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans. Use of an isolated protein according to claim 1.   23. Use according to claim 22, wherein the condition is Alzheimer's disease.   21. A therapeutically effective amount of claim 14-20 for use in the treatment of a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in mammals, including humans. A pharmaceutical composition comprising an isolated protein according to any one of the above and a suitable pharmaceutical carrier for them.   25. A pharmaceutical composition according to claim 24, wherein the condition is Alzheimer's disease.   A method of treating a condition selected from the group consisting of Alzheimer's disease, familial Danish dementia and familial British dementia in a mammal, including a human, in need of treatment, comprising a therapeutically effective amount of 25. Administering the isolated protein of any one of claims 1-4 and 14-20 or the pharmaceutical composition of any one of claims 10 and 24 to the mammal. Method.   27. The method of claim 26, wherein the condition is Alzheimer's disease.   28. A method according to any one of claims 26 and 27, wherein the treatment is selected from the group consisting of prophylactic, palliative and curative treatments.