Patent Application
20160030553
The present invention is related to an allergen preparation.
Common allergens are pollens, house dust mites, moulds, drugs, foods and animal hair and dander.
The most common allergy diseases are rhinitis, asthma and atopic dermatitis. Allergic asthma is a chronic inflammatory disorder. Symptomatic treatment of allergic disorders is effected by use of antihistaminis, β-antagonists and corticosteroids.
Furthermore, the so called “specific” immunotherapy is based on a hyposensitization. Typically, patients are administered with subcutaneous injection of the specific offending allergens. Treatment is started with small allergen doses and the doses are increased. Treatment is typically maintained for several years. This type of treatment suffers from poor patient compliance and has been questioned due to safety reasons because a patient can suffer from severe anaphylactic reactions.
In addition to methods comprising repeated subcutaneous injections there are also oral hyposensitization methods.
U.S. Pat. No. 4,822,611 discloses a method for treating allergies comprising oral treatment with allergens. It describes the use of commercially available “bulk” allergenic extracts showing batch-to-batch variation and differences in extracts from different manufactures. The preparation of these extracts is not described.
GB 1 247 614 discloses a method of extracting an allergen. The aim of this method is to have a more complete and effective allergenic extract by including all extractable components of the allergen.
U.S. Pat. No. 5,770,698 discloses a process for purifying extracts of allergenically active proteins. The spectrum of
WO 99/22762 discloses a similar method; therefore, the product comprises large amounts of non-protein impurities, too.
On the other hand, there has been a tendency to develop highly specific preparations based on single epitopes. For example, WO 00/58349 discloses an isolated and purified peptide comprising a leucin positioned two peptide bonds away from a tyrosine/arginine pair. These peptides can be used to prepare a pharmaceutical composition to accomplish treatment or prophylaxis, in this case especially directed to allergy in dogs.
On the one hand, methods are used to purify a specifically identified single allergenic molecule. On the other hand, people are trying to produce allergenic extracts as complete as possible.
According to the first alternative, it is always possible that the allergen preparation lacks the relevant epitopes to induce tolerance in a determined patient. The second alternative has a drawback of batch-to-batch variability and of the presence of compounds able to trigger immune response like DNA molecules, carbohydrates, lipids of complexes thereof.
WO 2008/000793 describes a method of purifying allergens overcoming at least some of the drawbacks of prior art, especially to provide antigens from natural allergens with a significant reduced capability to trigger allergenicity reaction compared to the crude allergen extract but able to stimulate T-cells as well.
WO 2012/172037 discloses a method for the production of hydrolyzed allergens.
Despite significant progress, there is still a need to improve immunogenicity of allergen preparations, especially in the treatment of allergies.
It is an object of the present invention to provide allergen preparations having an improved immunogenicity and their use for the therapeutical applications for treating allergy.
The problem is solved by the provision of an allergen preparation comprising at least one allergen in an oil-in-water emulsion.
Oil-in-water emulsions are known in the art in the context of vaccine preparations; see WO 95/17210 and WO 2008/043774 and references cited therein.
It has been found, that adjuvants may improve the efficiency of an allergen preparation, thereby reducing the necessary amount of the allergen in the preparation. This improves safety. It has further been discovered that adjuvants like Al(OH)3 are not able to bind all allergen proteins/peptides in a similar way. That may negatively influence the efficiency in that some allergens show an improved stimulation of T-cells and B-cells, whereas others show a reduced stimulation. This problem is especially important, if not only a single purified allergen, but a mixture a allergenic proteins or hydrolysates of allergenic proteins is used.
An embodiment of the invention is an allergen preparation comprising an allergen in an oil-in-water emulsion. The allergen may be for example an allergen extract, a purified allergen extract, a denatured allergen extract or a hydrolyzed allergen extract.
Preferably, the allergen preparation comprises a metabolizable oil, water and one or more surfactants.
Preferably the metabolizable oil is selected from the group consisting of squalene, squalane, soybean oil, sesame oil and Miglyol 810 oil.
Preferably, the one or more surfactants surfactants is selected from the group consisting of Tween 80, CAMPUL POE-O low PV surfactant, SOLITOL HS15 surfactant, PLURONIC F68 block co-polymer, sodium cholate, glycerodeoxy cholate, sphingomyelin, sphingosine, 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine, L-a-phosphatidylethanolamine, 1,2-dipalmitoyl-sn-glycero-3phosphocholine and egg phosphatidyl choline, sorbitan trioleate or a mixture thereof.
Preferably, the concentration of the allergen is 0.1 to 200 μg/ml in the preparation (at 25° C.).
Preferably, the oil content of the preparation is 1 to 10% (w/w) of the preparation.
The amount of the at least one surfactant is preferably 1 to 30 (w/w) of the oil.
Preferred examples of o/w emulsions are e.g.
In a further embodiment, the o/w emulsion comprises at least squalene, an aqueous solvent and a polyoxyethylene alkyl ether.
In one embodiment, the o/w emulsions are prepared free of allergens. A solution comprising the allergen is then combined with the o/w emulsion at a ratio of 1:9 to 9:1 (w/w).
In a preferred embodiment, the allergen is an allergen extract, a purified allergen extract, a denatured allergen extract or a hydrolyzed allergen extract.
A preferred method for the production of the allergen extract of the present invention comprises the steps of
In some embodiments, the method is followed by
After the step d), a second denaturing step may be performed. For this denaturing step a second denaturing agent is used which can be the same or have different composition from step c). In a preferred embodiment the reducing agent used for the second denaturation step is TCEP.
It is preferred that the pH for the second denaturing step is set between 1.5 and 9.0. In a preferred embodiment the pH is lower than 7.0 or lower than 5.0 or lower than 3.0 but preferably higher than 1.0. Denaturing is preferably performed for at least 15 minutes, preferably at least 30 minutes and more preferably at least 60 minutes at a temperature between 15 and 40° C., preferably between 20 and 37° C.
In contrast to the methods of prior art, the methods produce allergen extracts which comprise predominantly proteins without purifying the extract to a single peptide or protein.
In contrast to the products of prior art the products of the invention have following advantages:
As starting materials, different natural occurring allergens can be used. Typical natural starting materials are milk, venom, egg, weed, grass, tree, shrub, flower, vegetable, grain, fungi, fruit, berry, nut, seed, bean, fish, shellfish, seafood, meat, spices, insect, mite including house dust mite, mould, animal, pigeon tick, worm, soft coral, animal dander, nematode, Hevea brasiliensis, and mixtures thereof.
Preferred allergens used in this invention are especially grass pollen, house dust mite, ragweed pollen, cow milk, egg white and peanuts. Preferably, the peanuts are selected among the Arachis genus, preferably from hypogaea species, more preferably from hypogaea and fastigiata. Sub-species comprise Virginia, Spanish, Valencia varieties and/or hydrids such as Runner or even transgenic peanuts obtained by genetic engineering. Preferably, a mixture of at least 2, preferably 3 species/sub-species/varieties/hybrids and/or transgenic peanuts is used. In a preferred embodiment the red seed coat (tegument) of the peanuts has been removed.
Alternatively, synthetic sources of allergens as starting materials can be used. Synthetic sources of allergens means biotechnological produced proteins like recombinant proteins and/or genetically modified organisms.
Preferably, the source comprises a mixture of allergens.
The allergen preparation of the present invention can be used for the preparation of a pharmaceutical composition and/or food composition for inducing tolerance and desensitization. Induction of tolerance can be used to cure or prevent allergic reactions.
The allergic reaction to be treated or prevented depends on the source of allergens, i.e. allergy to peanuts are prevented or treated by using allergens from peanuts, whereas allergy to grass pollen are treated with allergens from grass pollen.
After extraction of the material, the extract is purified to remove non-protein components such as sugars, lipids, nucleic acids and the like. Typical, several different proteins are present in the protein fraction of the purified extract.
According to prior art, one protein is purified and the other remaining proteins are “impurities”.
In contrast thereto, it is the aim of the present invention to purify the proteins together. The relative amounts of the proteins in the purified extract can be easily measured using methods like SDS-PAGE followed by densitometry.
For 60% of total weight of the proteins, it is necessary to count the two most dominant proteins at least, i.e. no single protein is 60% (w/w) or more of all proteins. More preferably, 60% of all proteins are formed by the at least 3 dominant proteins, preferably by the at least 4 dominant proteins and more preferably by at least 5, 6, 7, 8, 9 or 10 proteins.
For example, there are the following proteins:
Protein 1: 27%
Protein 2: 13%
Protein 3: 34%
Protein 4: 19%
Protein 5: 17%
The most dominant proteins forming together at least 60% (≈60% or more) are proteins 3+1 (34+27=61%).
Furthermore, the total protein content of the purified extract is at least 60% by weight; preferably the content is at least 70% by weight or 80% by weight, more preferably 90% by weight of the purified extract.
Extraction is preferably performed with aqueous solutions. Suitable salts are salts such as but not restricted to carbonate, bicarbonate, phosphate, acetate, TRIS and HEPES.
Also in contrast to many other extraction methods, it is preferred that the amount of extraction medium is comparatively large, i.e. at least 20 times the weight of the natural source of allergens, preferably 100 time the weight or more.
Purifying of the extract may be performed by one or more of the following:
In a preferred embodiment ion exchange chromatography is used wherein in case of a cation exchanger the loading solution has a pH between the pKa of the acidic function of the cation exchanger and the pKa of the protein having the lowest pKa of the proteins in the extract. In case of an anion exchanger the pH is between the pKa of the basic function of the anion exchanger and the pKa of the protein having the highest pKa of the proteins constituting the extract.
Through this method all proteins bind to the ion exchanger while the neutral impurities and the impurities with the same charge as the ion exchange resin will be removed.
In a preferred embodiment, at least one purification step is performed with a solution comprising one or more of a tenside and/or a denaturing agent. The tenside may be non-ionic, anionic, cationic or amphoteric. Suitable denaturing agents are chaotropic agents, reducing agents and mixtures thereof. Suitable denaturing agents are for example urea, guanidinium chloride, ethylene glycol, isopropanol. A suitable concentration of urea is 3 M or more, preferably 4 M or more. A suitable concentration of guanidinium is preferably 2 M, preferably 3 M or more. A suitable concentration of ethylene glycol and/or isopropanol is 5% or more, more preferably 10% or more, up to 20% by weight.
In some cases, the production of the purified extract is sufficient. Extracts of this type may be used to produce ex vivo/in vivo and in vitro diagnostics, prophylactic and therapeutic treatment of allergic diseases.
In some embodiments, the method is further comprises a step of
This step may follow after denaturation (first or second) or after refining.
It could be shown that some allergens show better hydrolyzation after a two step denaturation.
The advantages of the product obtained thereby are that the peptides are the digestion result of denatured proteins.
In some embodiments, the hydrolysis is followed by
Due to a specified size calibration they have a reduced potency to induce immediate allergic reaction and pro-inflammatory reaction as well.
Denaturing, if necessary is preferably performed in the presence of chaotropic agents, reducing agents or mixtures thereof. Suitable chaotropic agents are for example urea and guanidinium chloride. Typical reducing agents are for example dithiotriethol, β-mercaptoethanol, thio-glycerol and mixtures thereof.
The hydrolysing step is typically performed with an enzyme. Suitable enzymes are for example pepsin, trypsin, chymotrypsin. This hydrolyzing step can be performed in the presence of a chaotropic agent, preferably urea or guanidinium chloride, too. During hydrolysing the concentration of urea and guanidinium chloride should be below 4 M, preferably below 3M.
The hydrolyzing step can also be performed in presence of a reducing agent, preferably TCEP. During hydrolysis, the concentration of TCEP is preferably below 10 mM. Preferably, pepsin is used. More preferably, pepsin at a pH range of 1.0-3.0 is used.
In the size calibration step, peptides with a molecular weight larger than 10,000 Da or smaller than 1,000 Da, are removed to some extent.
The peptides of the purified hydrolysate, therefore, comprise peptides with a molecular weights between 1,000 and 10,000 Da. Suitable methods for removing large or small peptides are ultrafiltration and size exclusion chromatography. Again this size exclusion chromatography may be performed in the presence of a chaotropic agent, for example urea, guanidinium chloride, ethylene glycol, isopropanol and mixtures thereof.
Preferably, less than 10% of the peptides have a molecular weight above 10.000 Da and less than 20% of the peptides have a molecular weight below 1.000 Da so that 70%, or more preferably 80% of the peptides are between 10.000 Da and 1.000 Da.
One advantage of the hydrolysate is that the peptides are the digestion result of purified denatured proteins. They have a reduced potency to induce immediate allergic reactions and co-inflammatory reactions as well.
A further embodiment of the invention is an allergen extract obtainable by the method of the present invention. Typically also in this extract the most dominant proteins by weight, which form together at least 60% by weight of all the proteins, are at least 2 proteins, preferably at least 3 or 4 proteins or more preferred at least 5, 6, 7, 8, 9 or 10 proteins. The purity is seen by a Optical Density 260 nm:Optical Density 280 nm-ratio of <1, preferably <0.9, more preferably between 0.75 and 0.9.
A further embodiment is an allergen hydrolysate obtainable by the method. It can be used for
The allergen extract of the present invention can be used for the preparation of a pharmaceutical composition and/or food composition for inducing tolerance. Induction of tolerance can be used to cure or prevent allergic reactions.
An embodiment of the present invention is a pharmaceutical composition comprising the allergen preparation of the present.
Additionally, pharmaceutical composition may comprise one or more of the following substances: nucleoside triphosphates, nucleoside diphosphates, nucleoside monophosphates, nucleic acids, peptide nucleic acids, nucleosides or analogs thereof, immunosuppressive cytokines, compounds inducing expression of immunoproteasomes, 1,25-dihydroxyvitamin D3 or analogs thereof, lipopolysaccharides, endotoxins, heat shock proteins, thioredoxin with either NADPH or NADP-thioredoxin reductase, dithiothreitol, adrenergic receptor agonists such as salbutanol, adrenergic receptor antagonists such as butoxamine, compounds that regulate the expression of the adhesion molecule ICAM-1, N-acetyl-L-cysteine, γ-L-glutamyl-L-cysteinyl-glycine (reduced L-glutathione), alpha-2-macroglobulins, inducers for Foxp3 gene expression, flavonoids, isoflavonoids, pterocarpanoids, stilbenes such as resveratrol, tachykinin receptor antagonists, chymase inhibitors, vaccine adjuvant like CpG or MPL or tolerogenic adjuvant like zymosan, beta-1,3-glucan, regulatory T-cell inducer, a muco-adhesive agent for attaching the particle to the intestinal mucosal lining such as a plant lectin, zinc, zinc salts, polysaccharides, vitamins and bacterial lysates.
“Extracting” as used herein is a treatment of an allergen source with an extraction medium including water, buffer or organic solvents to separate soluble ingredients from a non-soluble residue. The use of aqueous systems (comprising at least 50% H2O) is preferred.
“Denaturing” as used herein is a process in which the proteins lose their quaternary, tertiary and secondary structure, especially this term refers to the treatment with one or several denaturing agents.
A further embodiment of the present invention is a pharmaceutical composition comprising the allergen preparation of the present invention. Additionally, the pharmaceutical composition may comprise one or more of the following substances: nucleoside triphosphates, nucleoside diphosphates, nucleoside monophosphates, nucleic acids, peptide nucleic acids, nucleosides or analogs thereof, immunosuppressive cytokines, compounds inducing expression of immunoproteasomes, 1,25-dihydroxyvitamin D3 or analogs thereof, lipopolysaccharides, endotoxins, heat shock proteins, thioredoxin with either NADPH or NADP-thioredoxin reductase, reducing agent, dithiothreitol, adrenergic receptor agonists such as salbutanol, adrenergic receptor antagonists such as butoxamine, compounds that regulate the expression of the adhesion molecule ICAM-1, N-acetyl-L-cysteine, γ-L-glutamyl-L-cysteinyl-glycine (reduced L-glutathione), alpha-2-macroglobulins, inducers for Foxp3 gene expression, flavonoids, isoflavonoids, pterocarpanoids, stilbenes such as resveratrol, tachykinin receptor antagonists, chymase inhibitors, vaccine adjuvant or immunomodulators like CpG, aluminum hydroxide, calcium phosphate, TLR-4 agonists (i.e. MPL) and TLR-9 agonists or tolerogenic adjuvant like zymosan, beta-1,3-glucan, regulatory T-cell inducer, a muco-adhesive agent for attaching the particle to the intestinal mucosal lining such as a plant lectin, zinc, zinc salts, polysaccharides, vitamins and bacterial lysates or particles displaying surface linked antibodies.
In a preferred embodiment, the pharmaceutical composition is prepared for subcutaneous administration, nasal administration, epicutaneous administration, intralymphatic administration, oral administration, for sublingual drug delivery, or for enteric drug delivery.
All references cited herein, including WO 2008/000783 and WO 2012/172037, are incorporated by reference to the full extent to which the incorporation is not inconsistent with the express teachings herein.
The method of the present invention is further exemplified by the following, non-limiting examples.
1% (w/v) pollen (Lolium perenne from ALLERGON) was added to sodium bicarbonate (12.5 mM) and incubated 2 h under stirring. The solution was then clarified and filtrated by adding celite (ACROS) at 2% (w/v) and passing through a 0.2 μm filter. This sample constitutes the crude extract.
The presence of allergens in the extract was analyzed by western blotting using pollen allergic patient sera. IgG and IgE epitopes are visualised with anti-human IgG or IgE antibodies.
As shown on
The said crude extract was acidified to pH 3.0 and Tween 20 (0.1%, v/v) was added. This sample constitutes the acidified extract.
The allergen extract was purified by:
A sartobind S− membrane (SARTORIUS) was equilibrated with 28× Bed volume (By) of sodium bicarbonate 12.5 mM, citrate 30 mM, pH 3.0, Tween 20 0.1% (v/v). The said acidified extract was loaded on the equilibrated membrane. The column was washed first with 35× Bv of sodium bicarbonate 12.5 mM, citrate 30 mM, pH 3.0, Tween 20 0.1% (v/v) and then washed with 42× By of sodium bicarbonate 12.5 mM, citrate 30 mM, pH 3.0. The proteins were eluted with carbonate 0.1 M, sodium chloride 0.5 M, pH 9.15. The presence of proteins was followed the OD at 280 nm. The fractions of interest were pooled.
This step was performed at 0-4° C.
A quantity of ammonium sulfate to reach 90% of saturation was added to the product under stirring. The stirring was stopped after the complete dissolution of the salt. The suspension was incubated overnight and centrifuged 2 times during 15 min at 10,000 g. The supernatant was each time carefully discarded.
The pellets were resuspended at 9 mg/ml in urea 6 M, DTT 10 mM, Tris.HCl 0.1 M, pH 8.0 and incubated at 37° C. for 1 h.
The denatured sample was loaded on the column and the proteins were eluted with Tris.HCl 25 mM, urea 1.5 M, pH 8.0.
The presence of proteins was followed by the OD measurement at 280 nm The fractions of interest were pooled to constitute the purifed denatured allergen extract.
The purified allergen extract was further analysed. The protein content (BCA Assay) and the dry weight were determined in order to evaluate the protein purity. The purification efficiency was also followed by the removal of carbohydrates (Orcinol test) and by the decrease of the ratio OD260/OD280.
As shown in table 1, the purification process allows
The extract was hydrolyzed using the following protocol:
The said purified allergen extract was acidified to pH 2.0. The digestion was performed at 2.5 mg/ml of pollen proteins and 1 Eu. Ph. U of pepsin (MERCK) for 337 mg of proteins, at 37° C., during 2 h.
In order to eliminate the peptides with a MW ≧10,000 Da and MW ≦1,000 Da, the hydrolysate was purified by
The efficiency of the purification was controlled by size exclusion HPLC. A BioSep-SEC S2000 column (PHENOMENEX) was equilibrated with Na2HPO4 50 mM—SDS 0.5% (w/v) pH 6.8 at a flow rate of 1 ml/min. The peptides were detected at 214 nm.
The 10 kDa and 1 kDa limits were calculated from a calibration curve as exemplified in
As shown on
Allergenicity properties of the pollen crude extract (according to example 1), purified pollen proteins (according to example 2) and purified pollen peptides (according to example 4) were assessed by measuring their capacity to induce basophile degranulation.
The test was performed in vitro on fresh human blood samples from pollen allergic volunteers incubated with increasing concentrations of pollen crude extract, purified proteins and purified peptides. Basophile degranulation was assessed by measuring, by flow cytometric method, the expression of the gp53 protein marker on the cell membrane of activated cells (i.e. IgE positive cells). This protein is normally present within the membrane of the granules in resting cells and appears on the cell surface upon cell activation (due to the fusion of the granule membrane with the cytoplasmic membrane). It therefore becomes detectable by labeled specific anti-gp53 antibodies. As shown on
To analyze the effect of adjuvants, the immunogenicity of peanut peptides or denatured peanut protein together with different adjuvants was analyzed.
Treatment of Mice Seven-week-old female naïve Balb/c mice were injected subcutaneously, once a week for 6 weeks, with peanut peptides (100 μg) or peanut proteins (25 μg) alone or in combination with different adjuvants: a squalene-based oil-in water emulsion, aluminium hydroxide (500 μg Al3+ per injection), aluminium phosphate (500 μg Al3+ per injection) and calcium phosphate (200 μg Ca2+ per injection). One group of mice receiving a solution of placebo was also included in the study. Blood samples were collected on days 0, 14, 28, 49 and 63 to measure immunoglobulin level induced by treatments.
Dosage of Immunoglobulins G (IgG) Specific for Peanut Proteins in Animal Serum
Microtiter plates were coated with peanut proteins (2 μg/ml) in carbonate buffer, over night at 4° C., washed and blocked for 1 hour at 37° C. with a solution of PBS 0.05% Tween containing a non relevant protein. Wells were incubated with serial dilutions of serum samples (from 1/100 to 1/4374000), for 1 hour at 37° C. Bound IgG were detected with anti-mouse IgG coupled to horseradish peroxydase (incubation of 1 hour at 37° C.). After washing, plates were incubated with TMB substrate and the reaction was stopped with 1M H3PO4. Absorbance was measured at 450 nm and 650 nm.
The results are expressed as titre of peanut-specific IgG which corresponds to inverse of the serum dilution giving an optical density of 0,3.
Preparation of Peanut Peptides
Preparation of peanut allergens and hydrolyzed peptides was performed in accordance with the method described in WO 2012/172037, incorporated by reference.
Results
As shown in
No production of peanut-specific IgG was observed after 6 injections of 100 μg peanut peptides alone or adsorbed on calcium phosphate and aluminium phosphate (
| Number | Date | Country | Kind |
|---|---|---|---|
| 13160006.6 | Mar 2013 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2014/055516 | 3/19/2014 | WO | 00 |
