U.S. patent application number 14/435262 was filed with the patent office on 2015-09-10 for compositions for immunotherapy.
The applicant listed for this patent is HAL ALLERGY HOLDING B.V.. Invention is credited to Dirk Jan Elbertus Opstelten, Joanna Paulina Maria van der Kleij.
Application Number | 20150250870 14/435262 |
Document ID | / |
Family ID | 47071270 |
Filed Date | 2015-09-10 |
United States Patent
Application |
20150250870 |
Kind Code |
A1 |
van der Kleij; Joanna Paulina Maria
; et al. |
September 10, 2015 |
Compositions for Immunotherapy
Abstract
The present invention relates to compositions which can be used
in immunotherapy and especially to compositions which can be used
in immunotherapy for mammals suffering from a peanut allergy. The
present invention further relates to the use of the present
compositions for the treatment of a mammal suffering from an
allergy by immunotherapy and the use of the present compositions in
a prophylactic treatment for desentizing the immune system of a
mammal for an allergen. Specifically, the present invention relates
compositions suitable for immunotherapy comprising an allergen,
wherein substantially 100% of said allergen in said composition is
complexed with aluminum. The allergen, e.g. peanut kernel protein
extract, is preferably reduced and alkylated in these
compositions.
Inventors: |
van der Kleij; Joanna Paulina
Maria; (Haarlem, NL) ; Opstelten; Dirk Jan
Elbertus; (Oegstgeest, NL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HAL ALLERGY HOLDING B.V. |
Leiden |
|
NL |
|
|
Family ID: |
47071270 |
Appl. No.: |
14/435262 |
Filed: |
October 19, 2012 |
PCT Filed: |
October 19, 2012 |
PCT NO: |
PCT/EP2012/070810 |
371 Date: |
April 13, 2015 |
Current U.S.
Class: |
424/275.1 ;
424/757 |
Current CPC
Class: |
A61K 2039/55505
20130101; A61K 39/35 20130101; A61P 37/08 20180101 |
International
Class: |
A61K 39/35 20060101
A61K039/35 |
Claims
1. Composition suitable for immunotherapy comprising an allergen,
wherein substantially 100% of said allergen in said composition is
complexed, or conjugated, with aluminum.
2. Composition according to claim 1, wherein said allergen is a
peanut kernel protein extract.
3. Composition according to claim 2, wherein said peanut kernel
protein extract is modified by reduction and subsequent
alkylation.
4. Composition according to claim 2 or claim 3, wherein said peanut
kernel protein extract comprises at least Ara h1, Ara h2 and Ara h6
or Ara h2 and Ara h6.
5. Composition according to claim 1, wherein said allergen is an
allergenic protein.
6. Composition according to claim 5, wherein said allergenic
protein is selected from the group consisting of food proteins and
venom proteins.
7. Composition according to any of the claims 1 to 6, said
composition further comprises pharmaceutically acceptable carriers,
diluents and/or excipients.
8. Composition comprising an allergen, wherein substantially 100%
of said allergen in said composition is complexed, or conjugated,
with aluminum, for use in the treatment of a mammal suffering from
an allergy by immunotherapy.
9. Use according to claim 8, wherein said mammal is a human
mammal.
10. Use according to claim 8 or claim 9, wherein said allergen is a
peanut kernel protein extract and said allergy is peanut
allergy.
11. Use according to claim 10, wherein said peanut kernel protein
extract is modified by reduction and subsequent alkylation.
12. Composition comprising an allergen, wherein substantially 100%
of said allergen in said composition is complexed, or conjugated,
with aluminum, for use in a therapeutic treatment for desentizing
the immune system of a mammal for said allergen or the use in a
prophylactic treatment of a mammal with high predisposition for
developing an allergy upon contact with said allergen.
13. Use according to claim 12, wherein said mammal is a human
mammal.
14. Use according to claim 12 or claim 13, wherein said allergen is
a peanut kernel protein extract and the immune system is
desensitized for exposure to peanuts.
15. Use according to claim 14, wherein said peanut kernel protein
extract is modified by reduction and subsequent alkylation.
16. Composition comprising an allergen, wherein substantially 100%
of said allergen in said composition is complexed, or conjugated,
with aluminum, for use in medicine.
17. Method for immunotherapy comprising administering to a mammal
suffering from an allergy, or a mammal at risk of developing an
allergy, a composition comprising an allergen, wherein
substantially 100% of said allergen in said composition is
complexed, or conjugated, with aluminum, in a sufficient amount and
during sufficient time to reduce, or eliminate, an allergic
response of said mammal to said allergen.
18. Method according to claim 17, wherein said mammal is a human
mammal.
19. Method according to claim 17 or claim 18, wherein said allergen
is a peanut kernel protein extract and the allergic response is an
allergic response to peanut exposure.
20. Method according to claim 19, wherein said peanut kernel
protein extract is modified by reduction and subsequent alkylation.
Description
[0001] The present invention relates to compositions which can be
used in immunotherapy and especially to compositions which can be
used in immunotherapy for mammals, such as human mammals, suffering
from peanut allergy. The present invention further relates to the
use of the present compositions for the therapeutic treatment for
desentizing the immune system of a mammal suffering from an allergy
by immunotherapy and the use of the present compositions in a
prophylactic treatment of a mammal with high predisposition to
develop a certain allergy.
[0002] Allergen immunotherapy, also termed hyposensitization
therapy, immunologic desensitization, hyposensibilization, or
allergen-specific immunotherapy, is a form of immunotherapy for
allergic disorders in which the patient is vaccinated with
increasingly larger doses of an allergen, i.e. the substance, or
substances, to which they are allergic, with the aim of inducing
immunologic tolerance.
[0003] Allergen specific immunotherapy is the only treatment
strategy which treats the underlying cause of an allergic disorder.
It is a highly cost-effective treatment strategy and results in an
improved quality of life.
[0004] Immunotherapy has been shown to produce long-term remission
of allergic symptoms, to reduce severity of associated allergic
response, as well to reduce the chances of new sensitizations to
allergens developing. Immunotherapy aims to modulate the immune
system's response to allergens.
[0005] Immunotherapy generally encompasses repeated exposure to a
specific allergen via, for example, sublingual or subcutaneous
routes, thereby providing a desensitization of the allergic patient
to the allergen and thus a reduction in allergic symptoms and use
of symptomatic based treatments.
[0006] The exact mechanism underlying immunotherapy is not fully
known but it is accepted that immunotherapy leads to alteration of
the immune response to an allergen. The modification at least
comprises a change in IgE synthesis and the production of IgE
blocking antibodies reducing the allergic response of the immune
system to specific allergens. Also an increase in conversion of Th2
to Th1/T regulatory cells is observed. At a molecular level, part
of the underlying mechanism relies on the preferential induction of
allergen-specific IgG to neutralize an allergen and a reduction of
allergen-specific IgE.
[0007] Immunotherapy generally involves exposing an allergic
patient to low doses of an allergen. The dose is gradually
increased on a regular, for example weekly, basis, until a
"maintenance" dose is reached. This translates in approximately
four months of weekly injections to reach the maintenance dose.
Once the maintenance dose is reached, the injections are
administered less often, for example once per month for a few
years. Generally, the longer the treatment and the higher the dose,
the greater the therapeutic benefit.
[0008] After successful completion of immunotherapy, long-term
protection can be expected for a period of 3 to 5 years or more.
Therapy can be repeated should symptoms begin to return or if the
individual becomes exposed to new allergens that were not included
in the previous treatment regimen.
[0009] Peanuts are one of the most common foods responsible for
food-induced allergy. A curative treatment for peanut allergy is
not yet available. Specific immunotherapy (SIT) using aqueous
peanut extract displayed an increased tolerance to oral ingestion
of peanuts. However, as reported by Nelson et al. (J. Allergy Clin.
Immunol. 1997 June;99(6 Pt 1):744-51), aqueous peanut extracts
resulted in unacceptable systemic reactions, even during the
maintenance injections. Accordingly, the Nelson et al. concluded:
"For clinical application of this method of treatment, a modified
peanut extract is needed."
[0010] Considering the clinical relevance of immunotherapy, there
is a continuous need in the art for compositions suitable for
immunotherapy and especially immunotherapy effective against peanut
allergy. A perquisite for these compositions is that the
compositions need to be, besides providing an alteration of the
immune response upon exposure to an allergen, safe, i.e. the
compositions must not trigger an allergic reaction and, in the most
severe case, an anaphylactic shock.
[0011] Considering the above need in the art, it is an object of
the present invention, amongst other objects, to provide
compositions suitable for immunotherapy and especially
immunotherapy directed to peanut allergy.
[0012] This object of the present invention, amongst other objects,
is met by a composition suitable for immunotherapy as defined in
the appended claims.
[0013] Specifically, this object of the present invention, amongst
other objects, is met, according to a first aspect, by a
composition suitable for immunotherapy comprising an allergen,
wherein substantially 100% of said allergen in said composition is
complexed with aluminum.
[0014] Within the context of the present invention, an allergen is
defined as an antigen capable of stimulating a hypersensitivity
reaction in atopic mammals through immunoglobulin E (IgE)
responses. Most mammals mount significant immunoglobulin E
responses only as a defense against parasitic infections. However,
some mammals may respond to many common environmental antigens.
This hereditary predisposition is also designated atopy. In atopic
mammals, non-parasitic antigens stimulate undesired IgE production,
resulting in hypersensitivity or allergy.
[0015] Common allergens include antigens found in animal products
such as Fel d 1 (cat allergy), fur and dander, cockroach calyx,
wool and dust mite excretion; drugs such as penicillin,
sulphonamides, and salicylates; foods such as celery and celeriac,
corn or maize, eggs (typically egg white), fruit, pumpkin,
egg-plant, legumes, beans, peas, peanuts, soybeans, milk, seafood,
sesame, soy, tree nuts, pecans, almonds, and wheat; insect stings
such as bee sting venom, wasp sting venom, and mosquito stings;
mold spores; latex; metal; and plant pollen such as grasses and
tree pollen.
[0016] Within the context of the present invention, the terms
"allergen", "allergens", "antigen" and "antigens" are used
interchangeably unless indicated otherwise.
[0017] The present inventors have surprisingly found that when
substantially 100%, such as more than 99%, of an allergen in a
preparation is complexed, or conjugated with, or bound to aluminum,
no clinically relevant allergic reactions, i.e. mast cell-mediated
systemic responses, are observed although the aluminum complexed
allergen is still capable of inducing an IgG response thereby
providing a composition especially suitable to be used in
immunotherapy.
[0018] Mast cell-mediated systemic responses can be readily
measured by a lowering of the body temperature after exposure to an
allergen.
[0019] According to a preferred embodiment of this first aspect of
the present invention, the present aluminum complexed, bound, or
conjugated allergen is a peanut kernel protein extract, preferably
a peanut kernel protein extract being modified by reduction and
subsequent alkylation.
[0020] The present peanut kernel protein extract can be obtained by
a) grinding peanuts for providing a peanut powder; b) incubating
the peanut powder in acetone during 30 minutes using 5 grams peanut
powder per 50 ml acetone for providing a defatted peanut powder; c)
drying the defatted peanut powder; d) suspending the dried peanut
powder in a buffer with a pH between 7 and 9; and e) isolating the
resulting supernatant of step (d) thereby providing a peanut kernel
protein extract.
[0021] Reduction of the present peanut extract can be provided by
contacting the extract with one or more reducing agents chosen from
the group consisting of 2-mercaptoethanol (.beta.-ME),
dithiothreitol (DTT), dithioerythritol, cysteine, homocystein,
tributylphosphine, sulfite, tris(2-carboxyethyl) phosphine (TCEP),
sodium (cyano) borohydride, lye, glutathione, E-mercapto
ethylamine, thioglycollic acid, methyl sulfide, and ethyl
sulfide.
[0022] Subsequent alkylation of the present extract can be provided
by contacting the reduced extract with one or more alkylating
agents chosen from the group consisting of N-ethylmalimide,
cystamine, iodoacetamide, iodoacetic acid, alkylhalogenides;
alkylsulfates; alkenes, preferably terminal alkenes
(H.sub.2C)=C(H)--R, and enzymes.
[0023] According to another preferred embodiment of this first
aspect of the present invention, the present a peanut kernel
protein extract comprises at least the major peanut allergens Ara
h1, Ara h2 and Ara h6.
[0024] Peanut allergenic protein Ara h1 was described as a 63.5 kDa
protein occurring naturally in a trimeric form of approximately 180
kDa through non-covalent interactions. The trimeric Ara h1
structures often aggregate, forming multimers of up to 600-700 kDa.
Peanut allergenic protein Ara h2 migrates as a doublet at
approximately 20 kDa. This doublet consists of two isoforms that
are nearly identical except for the insertion of the sequence
DPYSPS in the higher molecular weight isoform. Peanut allergenic
protein Ara h6, was identified as a protein with a molecular weight
of approximately 15 kDa based on SDS-PAGE and 14,981 Da as
determined by mass spectroscopy.
[0025] According to yet another preferred embodiment of this first
aspect of the present invention, the present allergen is an
allergenic protein, preferably of protein selected from the group
consisting of food proteins or venom proteins.
[0026] The present composition preferably comprises
pharmaceutically acceptable carriers, diluents and/or
excipients.
[0027] Considering the beneficial properties of the present
compositions in immunotherapy, the present invention relates,
according to a second aspect, to a composition comprising an
allergen, wherein substantially 100% of said allergen in said
composition is complexed with aluminum, for use in a therapeutic or
prophylactic treatment of a mammal, preferably a human mammal,
suffering from an allergy by immunotherapy.
[0028] According to an especially preferred embodiment of this
second aspect, the allergen is a peanut kernel protein extract,
preferably modified by reduction and subsequent alkylation, and the
allergy is peanut allergy.
[0029] Considering the beneficial properties of the present
compositions in immunotherapy, the present invention relates,
according to a third aspect, to a composition comprising an
allergen, wherein substantially 100% of said allergen in said
composition is complexed with aluminum, for use in a prophylactic
treatment for desentizing the immune system of a mammal, preferably
a human mammal, for said allergen.
[0030] According to an especially preferred embodiment of this
third aspect, the allergen is a peanut kernel protein extract,
preferably modified by reduction and subsequent alkylation, and the
immune system is desensitized for exposure to peanuts.
[0031] According to a fourth aspect, the present invention relates
to a composition comprising an allergen, wherein substantially 100%
of said allergen in said composition is complexed with aluminum,
for use in medicine.
[0032] According to a fifth aspect, the present invention relates
to a method for immunotherapy comprising administering to a mammal,
preferably a human mammal, suffering from an allergy a composition
comprising an allergen, wherein substantially 100% of said allergen
in said composition is complexed with aluminum, in a sufficient
amount and during sufficient time to reduce, or eliminate, an
allergic response of said mammal to said allergen.
[0033] A typical sufficient amount will be from about 0.1 ng/kg to
10 mg/kg, 10 ng/kg to about 100 .mu.g/kg, or 0.1 .mu.g/kg to 1
.mu.g/kg of the aluminum complexed allergen relative to the body
weight of the individual to which it is administered. Often, a
treatment will comprise starting with the administration of dosages
at the lower end of these ranges and increasing the dosages as the
treatment progresses.
[0034] For desensitization treatment, it is typically necessary for
the patient to receive frequent administrations, e.g., initially
every one, two or three days, gradually reducing to once every two
or three weeks. Other suitable desensitization programs include
subcutaneous injections once every 2-4 weeks the dosage of which
injections may gradually increase over a period of 3-6 months, and
then continuing every 2-4 weeks for a period of up to about 5
years. It is also possible, particular for sublingual
administration, that daily administrations are given.
[0035] Desensitization protocols may also comprise a form of
treatment conventionally known in various equivalent alternative
forms as rapid desensitization, rapid allergen immunotherapy, rapid
allergen vaccination, and rapid or rush immunotherapy. In broad
terms, this procedure aims to advance an allergic patient to an
immunizing or maintenance dose of extract (i.e., allergen) by
administering a series of injections (or via another suitable
carrier) of increasing doses of the allergen at frequent (e.g.
hourly) intervals. If successful, the patient will exhibit an
improved resistance to the allergen, possibly even presenting a
total non-reactivity to any subsequent allergen exposure.
[0036] Various desensitization protocols are known in the art and
may for instance comprise a method of treating a patient having an
immediate hypersensitivity to an allergen using an accelerated
rapid immunotherapy schedule in combination with a method of
pre-treating such patient with prednisone and histamine antagonists
prior to receiving the accelerated immunotherapy.
[0037] According to an especially preferred embodiment of this
fifth aspect, the allergen is a peanut kernel protein extract,
preferably modified by reduction and subsequent alkylation, and the
allergy is peanut allergy.
[0038] The present invention will be further detailed in the
following examples disclosing specifically preferred embodiments of
the present invention. In the examples, reference is made to
figures wherein:
[0039] FIG. 1: shows temperature changes in sensitized mice
challenged with different preparations of peanut extract adsorbed
to aluminum. Temperature changes were measured for 90 minutes after
challenge with 0.6 mg/mouse, 0.6 mg/mouse adsorbed to 0.18 mg/ml
alum, 0.45 mg/mouse alum, 0.9 mg/ml alum or 5.46 mg/ml alum. As a
control sensitized mice were challenged with PBS/alum;
[0040] FIG. 2: shows symptom scores of sensitized mice challenged
with different preparations of peanut extract adsorbed to aluminum.
Symptom scores were assigned after challenge on a scale from 0 (no
symptoms) to 5 (death).
[0041] FIG. 3: shows a schematic overview of the time lime used for
sensitization and challenge;
[0042] FIG. 4: shows the results of an i.p. challenge at day 98 in
vivo mouse model for peanut allergy;
[0043] FIG. 5: shows the results of an i.p. challenge at day 112 in
vivo mouse model for peanut allergy;
[0044] FIG. 6: shows the results mast protease secretion 1 (mMCP-1)
one day after challenge in vivo mouse model for peanut allergy;
[0045] FIG. 7: shows IgE, IgG1 and IgG2a antibody levels in all
groups tested of the in vivo mouse model for peanut allergy.
EXAMPLES
Example 1
Complexing of Aluminum and an Allergen Significantly Increases
Safety
Introduction
[0046] This example demonstrates that the complexing of aluminum
with an allergen significantly increases safety of a composition
used for immunotherapy. This was demonstrated using an antigenic
peanut extract coupled to different concentrations of aluminum
hydroxide. In an in vivo mouse model for peanut allergy, these
different test preparations were analyzed for safety.
Material and Methods
Mice
[0047] Five-week-old specific pathogen-free female C3H/HeOuJ mice
were purchased from Charles River, France. All mice were housed
under specific pathogen-free conditions within the animal care
facility at the Utrecht University, The Netherlands. Experiments
were approved by the Animal Experiments Committee of the Utrecht
University. The diet used contained vegetable protein (including
soy) but was free of peanut proteins.
Test Preparations
[0048] Previous studies have demonstrated that a challenge of 0.6
mg peanut extract (PE) per mouse that is not bound to aluminum
results in a profound anaphylactic response. It is also know that a
challenge with 0.1 mg PE is capable of inducing profound changes in
temperature and symptom score in sensitized mice.
[0049] In a pilot study, the relation between the amount of
aluminum added and the percentage of aluminum complexed peanut
extract was investigated. For this, different amounts of aluminum
hydroxide were added to a sample of peanut extract (100% protein)
and the sample was centrifuged to pellet the aluminum complexed
peanut extract. Subsequently, the percentage free protein in the
supernatant was determined for assessing the amount of pelleted,
thus aluminum complexed, allergen wherein the percentage aluminum
complexed allergen is 100%--the percentage free protein found in
the supernatant.
[0050] The different aluminum concentrations used in the present
example were based on the binding of .about.100% (5.46 mg/ml) or
.about.90% (0.9 mg/ml alum), .about.70% (0.45 mg/ml alum),
.about.40% (0.18 mg/ml alum) of the total extract. A positive
control (0.6 mg/ml PE without alum) was also included.
Sensitization and Challenge
[0051] Mice (n=6) were sensitized by intragastric (i.g.)
administration of 6 mg peanut extract (PE) and 15 .mu.g Cholera
Toxin (CT, List Biological Laboratories, Inc.) in 400 .mu.l PBS per
mouse on days 0, 1, 2, 7, 14, 21, 28. Control mice received PBS
with 15 .mu.g CT/mouse in 400 .mu.l PBS per mouse. On day 42, all
groups of mice were subcutaneously (s.c) challenged in the neck
with 200 .mu.l of the different test preparations or their
respective control.
Assessment of Anaphylaxis
[0052] As an objective parameter of anaphylactic shock, body
temperature was measured by means of rectal thermometry every 10-20
minutes for 90 minutes after s.c. challenge. In addition, clinical
symptoms were scored using a scoring system from 0 (no symptoms) to
5 (death).
Results
[0053] The percentage aluminum complexed peanut extract was
determined and the results are summarized in Table 1 below.
TABLE-US-00001 TABLE 1 Percentage aluminum complex peanut extract
Aluminum hydroxide Percentage Preparation concentration Percentage
free complexed per mouse (mg/ml) protein protein 0.6 mg PE 0 100%
0% 0.6 mg PE 0.18 60% 40% 0.6 mg PE 0.45 30% 70% 0.6 mg PE 0.9 10%
90% 0.6 mg PE 5.46 0% 100%
[0054] A subcutaneous challenge with 0.6 mg non-complexed PE per
mouse resulted a severe anaphylactic shock response in all mice as
measured by their temperature drop (FIG. 1) and clinical symptom
score (FIG. 2). When the peanut preparation was fully (100%)
adsorbed to aluminum, none of the mice showed any signs of
anaphylactic shock symptoms.
[0055] Challenging mice with preparations containing different
amounts of aluminum only securing partial adsorption of PE resulted
in a delayed response in the groups challenged with the preparation
containing 60% and 30% non-adsorbed material. In the group
challenged with the preparation containing .about.10% non-adsorbed
material there was a delay as well as a decrease in the response.
Non-sensitized mice did not respond to any of the challenges (data
not shown) and sensitized mice that were challenged with aluminum
only also showed no response.
Conclusion
[0056] Mice that were sensitized and challenged with preparations
containing similar amounts of PE but varying amounts of alum
responded differently to a challenge. Complete (100%) binding of PE
to aluminum aborted the potency of the peanut extract whereas
partial binding still resulted in an anaphylactic response. The
present example clearly shows the potency of aluminum to prevent
mice from suffering an anaphylactic shock.
Example 2
Complexing of Aluminum and an Allergen Significantly Increases the
Response of the Immune System Resulting to an Increased Efficacy
Profile
Introduction
[0057] This example demonstrates that the complexing of aluminum
with an allergen significantly increases the response of the immune
system resulting to an increased efficacy profile. This was
demonstrated using an antigenic peanut extract coupled to aluminum
hydroxide. In an in vivo mouse model for peanut allergy an
immunotherapy, test preparations were analyzed for efficacy.
Material and Methods
Mice
[0058] Five-week-old specific pathogen-free female C3H/HeOuJ mice
were purchased from Charles River, France. All mice were housed
under specific pathogen-free conditions within the animal care
facility at the Utrecht University, The Netherlands. Experiments
were approved by the Animal Experiments Committee of the Utrecht
University. The diet used contained vegetable protein (including
soy) but was free of peanut proteins.
Sensitization and Challenge
[0059] Mice (n=6 per group) were sensitized by intragastric (i.g.)
administration of 6 mg peanut extract (PE) and 15 .mu.g Cholera
Toxin (CT, List Biological Laboratories, Inc.) in 400 .mu.l PBS per
mouse on days 0, 1, 2, 7, 14, 21, 28. Control mice received PBS
with 15 .mu.g CT/mouse in 400 .mu.l PBS per mouse. From day 42, all
groups of mice were subcutaneously (s.c.) de-sensitized in the
neck, twice a week for six weeks, with 200 .mu.l of the different
test preparations or their respective control (FIG. 3). The test
preparations were tested in a concentration of 0.1 mg/mouse per
injection and were either non-adsorbed or adsorbed to 1.82 mg/ml
aluminum.
Assessment of Anaphylaxis
[0060] As an objective parameter of anaphylactic shock, body
temperature was measured by means of rectal thermometry every 10-20
minutes for 90 minutes after i.p. challenge. One day after
challenge, blood was taken for the measurement of antibodies and
mMCP-1 (mast cell protease 1). On day 98 and 112, mice were
challenge i.p. and their body temperature was followed for 90
minutes after challenge.
Results
[0061] An i.p. challenge was given on day 98 and 112. The data show
that on day 112 both immunotherapy preparations (peanut extract
alone and adsorbed to alum) effectively reduced the anaphylactic
response as measured by the drop in temperature after challenge
(FIG. 5).
[0062] On day 98, the alum-adsorbed extract showed a greater
efficacy compared to the non-adsorbed extract (FIG. 4)
demonstrating that the presence of alum results in a preparation
that reaches efficacy at an earlier time point compared to the
non-alum preparation.
[0063] No differences between the 2 preparations were found in the
secretion of the mast protease 1 (mMCP-1) in the serum one day
after the challenge (FIG. 6). However, immunotherapy with both
preparations was capable of down-regulating mast cell activation,
as the release of mMCP-1 was significantly greater in the group of
allergic mice that did not receive immunotherapy (FIG. 6).
[0064] Antibodies (IgE, IgG1 and IgG2a) were determined in the
serum of all groups (FIG. 7). IgE levels were elevated in all
groups compared to the negative control (PBS). The group
de-sensitized with the alum-adsorbed peanut extract showed a trend
towards an elevated IgE level (Figure 7A) demonstrating a boost of
the immune system after the injection of an alum-adsorbed
preparation.
[0065] Mice that received immunotherapy displayed an increased
level of IgG1 in the serum with comparable levels between the
alum-adsorbed and non-adsorbed extract (FIG. 7B). The increase of
IgG2a levels (comparable with IgG4 in human) is dominated by the
group treated with the alum-adsorbed peanut preparation (FIG.
7C).
Conclusion
[0066] The adsorption of alum to a peanut extract results in a
boost of the immune system leading to an efficacious treatment at
an earlier time point. Without wishing to be bound to any theory,
this could be due to the elevated levels of IgG2a (comparable to
IgG4 in human) in the serum of these mice.
* * * * *