Patent Application
20120100163
The present invention is within the field of immunotherapy, treatment of hypersensitivity immune responses and bystander suppression.
Allergen-specific immunotherapy (SIT) was introduced into clinical medicine almost a century ago for the treatment of type I hypersensitivity immune responses and SIT is currently the only treatment leading to prolonged tolerance against allergens. In SIT, the specific allergen or a cross-reacting allergen thereof is repeatedly administered to the individual, usually either by subcutaneous administration or by sublingual administration, during a longer period, usually more than one year. Typically, the patient experiences lower symptom scores on re-exposure to the allergen(s) after some weeks or months treatment (Allergens and Allergen Immunotherapy 4th Ed, 2008, Ed by R Lockey and D Ledford, Informa healthcare).
One challenge encountered with SIT is that the allergen needs to be identified and that the individual undergoing SIT has significant elevated risk of getting severe systemic adverse reactions like anaphylaxis as well as local adverse reactions like swelling and itching. Therefore, there is a need to improve the treatment of a hypersensitivity immune response.
About 20 years ago, Miller et al (1991) demonstrated the principle of providing peripheral tolerance to an antigen (MBP) (myelin basic protein) in naïve rats not yet sensitized to MBP antigen by treatment of the naïve rats by intra-gastric administration of OVA (an antigen unrelated to MBP) before the rats were exposed to MBP for the first time. Miller et al (1991) found that the rats were only protected from developing EAE, if the rats were co-exposed to the unrelated antigen (OVA) along with being exposed to the MBP for the first time.
Later on several researchers have investigated bystander suppression to an immune response by administering an antigen unrelated to the antigen triggering the immune response.
For example, Dahlman-Hoglund et al (1995) have investigated the suppression of an immune response in naïve rats subsequent to feeding the naïve rats orally with a first antigen prior to challenging the naïve rat to a second antigen so as to trigger an inadvertent immune response. The investigators found that the immune response due to the second antigen was suppressed only where the rats were exposed to a mixture containing both the first antigen and the second antigen at the time of triggering the inadvertent immune response. In contrast, suppression of the immune response was not achieved when the first and second antigens were administered at two separate body parts of the rat.
The publication of Millington et al (2004) relates to feeding mice with a soluble protein (OVA) so as to induce bystander suppression to an unrelated antigen.
Oliveira CR et al (2005) have suggested bystander effect of a non-related antigen as an interesting mechanism to control sensitization to a new allergen in individuals already sensitized to one allergen. The authors have indicated that per-oral pre-treatment with OVA leads to bystander down regulation of specific antibodies towards the allergen, but only when OVA is present at the subsequent immunization.
The publication of Wang Lifang et al (2009) relates to antigen-driven bystander effect that accelerates epicutaneous sensitization with a new protein allergen. The publication of Brimnes et al (2009) relates to the investigation of sublingual immunotherapy in naïve mice. The publication of Kildsgaard et al (2005) relates to the investigation of sublingual immunotherapy in sensitized mice. The publication of Weiner et al (1997) relates to oral tolerance and treatment of autoimmune diseases. The publication of Rask et al (2010) relate to the investigation of sublingual immunotherapy in a mouse model of allergic inflammation. The publication of Brimnes et al (2007) relates to the investigation of sublingual immunotherapy in a mouse model of rhinitis. The publication of Kildsgaard et al (2007) relates to the investigation of sublingual immunotherapy in sensitized mice. The international patent application WO 2004/082710 relates to a product comprising i) a modulator of the Notch signalling pathway; and ii) an allergen or allergen bystander antigen or antigenic determinant thereof, or a polynucleotide coding for an allergen or allergen bystander antigen or antigenic determinant thereof; as a combined preparation for simultaneous, contemporaneous, separate or sequential use for modulation of the immune system.
In contrast to conventional allergen specific immunotherapy where the individual is treated with the specific allergen (incl. a mixture of allergens or cross-reacting allergens thereof) triggering the hypersensitivity immune response, the present invention relates to the treatment, including prophylactic treatment, of a hypersensitivity immune response in an individual with an antigen unrelated to the allergen triggering a hypersensitivity immune response in the individual. That is to say that the present invention also relates to bystander suppression of a hypersensitivity immune response.
The present inventors have provided evidence that a hypersensitivity immune response triggered by exemplary antigens in mice could be significantly reduced if the mice where pre-treated with another antigen unrelated to the “triggering” antigen. Interestingly, the alleviation of the hypersensitivity immune response was also reflected in clinically relevant readouts of an allergic immune response, e.g. reduction in number of sneezes or reduction in airway hyperresponsiveness. Even more interestingly, the alleviation of the hypersensitivity immune response could be demonstrated in mice pre-sensitized to the “triggering” antigen as well as in mice not sensitized to the “triggering” antigen. The inventors have also found that the immune response was only reduceable if the unrelated antigen is available together with the “triggering” antigen at the same time as the mice are challenged/exposed to the “triggering” antigen.
Thus, it may be understood that the present treatment of an immune response with an antigen unrelated to the “triggering” antigen only is workable, if the target organ of the “triggering” antigen is also exposed to the unrelated antigen at the same time as the “triggering” antigen. For example, it might be envisaged that the treatment with an unrelated antigen of an individual suffering from a hypersensitivity immune response due to exposure to an inhalation allergen is only workable, if the unrelated antigen is also exposed to the respiratory tract of the individual.
As recognized by the present inventors, it is a highly challenging task to ensure co-availability/co-exposure of both the antigen triggering the inadvertent immune response and the unrelated antigen at the organ target for the natural exposure of a “triggering” antigen. At least, it is envisaged that where the target organ is the respiratory tract, it is a challenge to ensure co-exposure of a pollen allergen and an unrelated antigen, unless the individual administers the unrelated antigen directly to the respiratory tract concomitantly with the airborne allergen material (e.g. pollen).
Also interestingly, the inventors have found that bystander suppression is more effective if the unrelated antigen is administered to a mucosa of the oral cavity, such as to a mucosa of the sublingual part of the oral cavity, rather than to a mucosa of the gastro-intestinal tract. To the best knowledge of the present inventors, they are the first to realize that bystander suppression is more efficient if the unrelated antigen is administered to a mucosa of the oral cavity.
Thus, a first aspect of the invention relates to a method for treatment or prophylactic treatment of a hypersensitivity immune response a hypersensitivity immune response of the respiratory tract in an individual in need thereof, such as to a method for bystander suppression of a hypersensitivity immune response of the respiratory tract in an individual in need thereof, wherein the immune response is triggered by an allergen upon the individual's exposure to an environmental source material comprising said allergen and wherein
A second aspect of the invention relates to a method for treatment or prophylactic treatment of hypersensitivity immune response of the gastro-intestinal tract in an individual in need thereof, such as to a method for bystander suppression of a hypersensitivity immune response of the gastro-intestinal tract in an individual in need thereof, wherein the immune response is triggered by an allergen upon the individual's exposure to a dietary source material comprising said allergen and wherein
A third aspect of the invention relates to a method for treatment or prophylactic treatment of a hypersensitivity immune response of the skin in an individual in need thereof, such as to a method for bystander suppression of a hypersensitivity immune response of the skin in an individual in need thereof, wherein the immune response is triggered by an allergen upon the individual's exposure to an environmental source material comprising said allergen and wherein;
In a sub aspect thereof, it should be understood that wherein the method/antigen is for use in treatment of a hypersensitivity immune response in an individual, the individual has specific IgE antibodies, such as specific serum IgE antibodies, against the allergen(s). Moreover, it should be understood that this individual does not necessarily present clinical symptoms of the hypersensitivity immune response at the time of treatment, but the individual is sensitized to an allergen.
In another sub aspect thereof, it should be understood that wherein the method/antigen is for use in prophylactic treatment of a hypersensitivity immune response in an individual, the individual does not have specific IgE antibodies, such as specific serum IgE antibodies, against the allergen at the time of initiating the prophylactic treatment. Generally, it is observed that individuals with histories of atopic diseases among their relatives might be in risk of developing a hypersensitivity immune response and many of those individuals will be sensitized to the same allergens as noted in already sensitized individuals. As such, wherein the sub aspect relates to prophylactic treatment of a hypersensitivity immune response, the same unrelated antigen as used in the treatment of individuals already sensitized to an allergen may be applied in the prophylactic treatment of an individual.
As recognized by the present inventors, the requirement of co-availability of both the “triggering” antigen and the unrelated antigen at a target organ can be practiced by various means. In the present invention, co-availability is achieved by by also administering the unrelated antigen to the relevant target organ of allergen exposure, such as by administering the unrelated antigen to the respiratory tract, gastro-intestinal tract or skin, which are recognized as main target organs for environmental allergens via inhalation and contact to skin or for dietary allergens via ingestion of food.
The following terms and phrases shall have the following meaning;
The term “a” or “an” refers to an indefinite number and shall not only be interpreted as “one” but also be interpreted in the meaning “some” or “several”.
The phrase “an allergen” shall be interpreted as one or more allergen(s).
The term “allergen” is meant to designate an allergen capable of eliciting a hypersensitivity immune response in an individual, such as in an animal, such as in a human. The allergen may be a sensitizing allergen or a cross-reacting allergen.
The term “sensitizing allergen” is meant to designate an allergen capable of triggering the immune system to produce IgE antibodies in an individual.
The term “cross-reacting allergen” defines an allergen that responds to IgE antibodies originally created against a sensitizing allergen. That is to say that a cross-reacting allergen is an allergen capable of eliciting a hypersensitivity immune response due to cross-reactive IgE antibodies induced by a sensitizing allergen. For example the allergen Mal d 1 of apples is a protein homologous to Bet v 1 of birch tree pollen, and able to elicit a hypersensitivity immune response in an individual pre-sensitized to bet v 1 allergen due to its ability to trigger mast cells loaded with IgE anti-Bet v 1.
The term “major allergen” shall mean an allergen that causes sensitization in more than 50% of a population of patients having a hypersensitivity immune response triggered by exposure to an allergen source material comprising said allergen.
The term “minor allergen” shall mean an allergen that causes sensitization in less than 50% of a population of patients having a hypersensitivity immune response triggered by exposure to an allergen source material comprising said allergen.
The phrase “antigen unrelated to an allergen” and the term “unrelated antigen” are interchangeable terms and are meant to designate a proteineous antigen distinct and different from an allergen, such as different from a sensitizing allergen as well as a cross-reacting allergen.
The phrase “antigen unrelated to an allergen triggering a hypersensitivity immune response in an individual” is meant to designate a proteineous antigen distinct and different from an allergen, such as different from a sensitizing allergen as well as a cross-reacting allergen capable of triggering a hypersensitivity immune response in the individual.
The phrase “antigen obtainable from a source material” is meant to designate that the antigen is isolated from the source material comprising the allergen or is otherwise isolated/obtained from another source material, but still identical to or at least essentially identical to the unrelated antigen present in the original source material comprising the allergen capable of triggering a hypersensitivity immune response in the individual.
The phrase “antigen derivable from a source material” is meant to designate an antigen identical to or at least essentially identical to the unrelated antigen present in the source material comprising the allergen capable of triggering a hypersensitivity immune response in an individual in need thereof, but reproduced by means of chemical and/or biological methods, such as by peptide synthesis and/or recombinant protein techniques according to methods well known in the art of proteins.
The term “antigen essentially identical to the unrelated antigen” is meant to designate that the antigen is slightly modified in relation to the unrelated molecule that is present or isolated from the source material comprising the allergen. Typical modifications are defined further herein.
The term “bystander suppression” is generally meant to encompass the ability to suppress an immune reaction in an individual towards one antigen (A) by treatment of the individual with another unrelated antigen (B).
The term “tolerance-induced bystander suppression” is generally meant to encompass the ability to suppress an immune reaction in an individual towards one antigen (A) by treatment of the individual with another unrelated antigen (B).
The term “co-availability” as used herein is meant to designate that the unrelated antigen is presented to the same target organ, such as to the same mucosa or skin, as reached by the “triggering” allergen through the natural exposure of a source material comprising the allergen. It does not necessarily mean that the unrelated antigen and the allergen are available or presented to the target organ at the exactly same time, but close enough in time to ensure that bystander suppression takes place. For example, the unrelated antigen is presented to/available at the target organ hours, days or weeks before, or after, the “triggering” allergen reaches the target organ. However, the unrelated antigen is preferably presented to the target organ within a period at least overlapping partly or entirely, such as coinciding partly or entirely, with the period where the triggering allergen is exposed to the same target organ.
The term “co-exposure” as used herein, is meant to encompass that the disease-eliciting antigen, such as the “triggering” allergen, and the unrelated antigen is exposed to the same target organ, e.g. the same mucosa upon the time where the individual is exposed to “triggering” allergen. It does not necessarily mean that the unrelated antigen and the sensitizing allergen are available or presented to the same body part at the same time, but close enough in time, to ensure that the bystander suppression takes place. For example, the unrelated antigen is presented to/available at the target organ hours, days or weeks before, or after, the “triggering” allergen reaches the target organ. However, the unrelated antigen is preferably presented to the target organ within a period at least overlapping partly or entirely, such as coinciding partly or entirely, with the period where the triggering allergen is exposed to the same target organ.
The term “immunotherapy” is meant to encompass therapy, wherein the therapeutically active agent (the immunomodulator) is an antigen. Immunotherapy usually encompass repeatedly administration of a sufficient dose of the antigen, usually in microgram quantities, over a prolonged period of time, usually for months or for years, wherein the antigen is administered daily, weekly, bi-weekly, or monthly.
The term “an individual” is meant to designate a mammal having an adaptive immune system, such as a human, a pet like a dog or a cat, and a farm animal like a horse or cattle.
The phrase “an individual in need of thereof” is meant to encompass an individual having a hypersensitivity immune response, an individual sensitized to an allergen as well as an individual in risk of being sensitized to an allergen or in risk of developing a hypersensitivity immune response. The individual may present clinically symptoms of a hypersensitivity immune response or the individual may only be sensitized to an allergen and not yet presenting clinically symptoms of a hypersensitivity immune response. An individual in risk of being sensitized to an allergen may be identified due to family histories of atopic individuals.
The phrase “an individual sensitized to an allergen” is meant to encompass an individual having specific IgE antibodies, such as serum antibodies, towards the allergen.
The phrase “prophylactic treatment” is meant to encompass treatment, such as by immunotherapy, of an individual with the aim to alleviate a hypersensitivity immune response or completely preventing the individual from developing a hypersensitivity immune response. Prophylactic treatment, such as prophylactic immunotherapy, is therefore initiated before the individual becomes sensitized to an allergen. This may be realized by initiating immunotherapy before the individual has raised detectable serum IgE antibodies capable of binding specifically to the sensitizing allergen or that any other biochemical marker indicative of a hypersensitivity immune response can be detected in biological samples isolated from the individual. Furthermore, prophylactic immunotherapy shall also designate immunotherapy initiated before the individual has evolved clinical symptoms of the disease, such as symptoms of allergic rhinitis or allergic asthma.
The term “treatment” refer to any type of treatment or prevention that imparts a benefit to a subject afflicted with or at risk of developing a hypersensitivity immune response to an allergen of interest, including improvement in the condition of the subject (e.g., in one or more symptoms), delay in the onset of symptoms or slowing the progression of symptoms, etc. As used herein, “treatment” is not necessarily meant to imply cure or complete abolition of symptoms, but refers to any type of treatment that imparts a benefit to a patient.
The phrase “therapeutically effective amount” is meant to designate an amount effective to treat, such as an amount sufficient to achieve the desirable effect. For example, a therapeutically effective amount is the total dose of an unrelated antigen administered during a period of immunotherapy in order to achieve the intended efficacy or the maximal dose tolerated within a give period. The total dose may be divided into single doses administered daily, twice a week, weekly, every second or fourth week or monthly depending on the route of administration. The total dose may be administered in different concentrations. It is expected that a single dose is in the microgram range, such as in the range of 5 to 500 microgram dependent on the unrelated antigen.
The phrase “sensitized to an allergen” is generally meant to encompass that the individual has been exposed to an allergen in a manner that the individual's adaptive immune system displays memory to the allergen, such as has raised detectable IgE antibodies against the allergen or that t-cells stimulated in-vitro are able to proliferate under the presence of the sensitizing allergen.
The term “sublingual route” and the term “sublingual administration” are interchangeable terms meant to designate that the unrelated antigen is administered topically or trans-mucosally to the sublingual mucosa of an individual. Preferably, the unrelated antigen is provided as a pharmaceutical formulation suitable for this purpose, such as a tablet, e.g. fast-disintegrating tablet, or as a solution for drop-wise administration.
The term “adjuvant” refers to a substance that enhances the immune response to an antigen. Depending on the nature of the adjuvant it can promote either a cell-mediated immune response, humoral immune response or a mixture of the two.
As shown in the Example section herein, the present inventors have studied bystander suppression by use of various experimental designs of murine models.
One of the experimental designs is a prophylactic murine model and is used in Examples 1 and 2. This model allows for investigating if prophylactic treatment with one antigen is able to down regulate a systemic inflammatory immune response caused by another antigen (triggering antigen) to which the first antigen is un-related to. Moreover, this model allows for investigating if the down regulation is dependent on the presence of the unrelated antigen at the systemic challenge. As a first step, naïve mice receive sublingual immunotherapy (SLIT) with the unrelated antigen in order to induce tolerance. Subsequently, the effect of the SLIT treatment is evaluated by inducing a systemic immune response by injecting the “triggering” antigen (i.e. allergen) adsorbed to alum intraperitoneally (i.p.). The immune response thus generated is generally characterized by spleenic T-cell proliferation and production of Th2 cytokines upon in vitro re-stimulation with the allergen. Therefore, the immune response generated in this simple prophylactic murine model reflects the human situation, where the individual undergoes prophylactic immunotherapy with the aim of preventing sensitization to a Th2-inducing allergen and/or preventing an immune response triggered by a Th2-inducing allergen.
To study bystander suppression, one group of mice is challenged with both the allergen and the unrelated antigen at the i.p. injection. Bystander suppression will be obtained in the mice, if splenic T-cells derived from mice treated sublingually with the unrelated antigen show reduced T-cell proliferation upon in vitro re-stimulation with the Th2-inducing allergen compared to T-cells derived from mice treated sublingually with placebo (buffer). In the current examples, two single antigens, OVA and Phleum p 5 allergen of grass pollen as well as a mixture of Pheum p allergens (aqueous allergen extract of grass pollen of the species Phleum Pratense) have been used as exemplary unrelated antigens. Two different Th2-inducing allergens, OVA and Phl p extract, have been used as exemplary allergens in triggering a Th2-like immune response in the murine models. For example, where OVA is applied as the unrelated antigen, the mice are challenged with the Phl p allergen extract, and vice versa with OVA as the challenge allergen.
Another experimental design of the prophylactive murine model is adopted in example 3 and 6 with the aim of demonstrating bystander suppression of airway inflammation and thus demonstrating bystander suppression of a clinically relevant immune response, as clinically relevant parameters like the fraction of eosinophils in the lung and airway hyper-reactivity are assessed. In this model, the i.p. injection that follows after the prophylactic SLIT treatment can be regarded as a sensitizing step, because it is followed by an intranasal challenge with the same allergen used at the i.p. sensitizing step. The additional step of intranasal challenge solely serves to induce airway inflammation clinically relevant to allergic asthma and rhinitis.
To study bystander suppression, one group of mice is challenged to both the allergen and the unrelated antigen at the i.p. injection. Bystander suppression will be obtained in mice sublingually treated with the unrelated antigen, if the mice show reduced eosinophilia and/or reduced airway hyper-reactivity compared to mice treated sublingually with placebo (buffer).
An experimental design of a therapeutic model mice model is used in Examples 4 and 5. The mice are first sensitized to the allergen by i.p. injection and subsequently treated by sublingual immunotherapy with an unrelated antigen. To study bystander suppression of a clinically relevant immune response, the mice are then challenged by intranasal installation of the allergen, either alone or together with the unrelated antigen with the aim of developing airway inflammation as may be observed by increased fraction of eosinophils in the lung, increased airway hyper-reactivity or increased sneezing, all relevant clinical symptoms of allergic asthma and rhinitis. Bystander suppression will be obtained in mice sublingually treated with the unrelated antigen, if the mice show reduced eosinophilia and/or reduced airway hyper-reactivity or sneezing compared to mice treated sublingually with placebo (buffer).
The murine models used herein are well known methods used in the field of studying specific allergen immunotherapy (J Brimnes et al, Clinical and Experimental Allergy 37, 488-497, 2007) and are models reasonably predictive for the efficacy in treatment of humans having the same immunological and clinically readouts as presented in the murine models used herein. Notably, the murine model presents many of the clinical and immunological features associated with human allergic rhinitis and asthma, including sneezing, increased airway hyperreactivity, influx of eosinophils as well as elevated levels of IL-5 and antigen specific IgE both locally and systemically (p 489 of J Brimnes et al 2007). The validity of the murine model of Brimnes et al 2007 has been confirmed in the Editorial of the publication in which the Brimnes article appeared, cf. “New allergy intervention strategies: hitting the mucosal road”, U Wiederrnann et al., Clinical and Experimental Allergy 37, 473-475, 2007.
The results presented herein may be summarized as follows:
As may be noted, bystander suppression could only be demonstrated where the mice also are challenged to the unrelated antigen when challenged to the “triggering allergen”. Therefore,
Thus, the present inventors have provided numerous data pointing to the fact that an antigen unrelated to the “triggering” allergen is able to provide bystander suppression of a hypersensitivity immune response, such as airway inflammation. Furthermore, the numerous data provided herein indicates that bystander suppression also is achievable by use of other not yet tested unrelated antigens and that bystander suppression also can be demonstrated with respect to hypersensitivity immune response of the gastro-intestinal tract (food allergy) or of the skin (atopic dermatitis or contact dermatitis). Bystander suppression of a hypersensitivity immune response triggered by a dietary allergen, like an allergen of peanut, milk, egg or soyabean, may be studied using the murine model outlined in Example 8 and bystander suppression of a hypersensitivity immune response triggered by an allergen associated with contact dermatitis or atopic dermatitis may be studied using the murine model outlined in Example 9.
As mentioned, uses and methods of the present invention encompasses the administration of an antigen unrelated to the allergen (i.e. the one or more allergen(s)) triggering a hypersensitivity response to the mucosa of the oral cavity as well as to the target organ for the exposure to the “triggering” allergen.
In principle any antigen can candidate as an unrelated antigen of the present invention as long as the unrelated antigen is different from and distinct to the one or more allergen(s) triggering a hypersensitivity immune response in the particular individual in need of treatment thereof and provided that co-availability of the “triggering” allergen and the unrelated antigen at the target organ is achieved. Therefore, an unrelated antigen of the present invention might be identified by determining whether the unrelated antigen can or cannot, at least in detectable levels, bind to IgE antibodies, such as serum IgE antibodies, obtained from the individual to be treated. Further criteria for the selection of a proper unrelated antigen for use in the present therapy may include that the unrelated cannot, at least in detectable levels, bind to IgE antibodies, such as serum IgE antibodies, obtained from a group of individuals that has specific IgE antibodies, such as specific serum IgE antibodies against an allergen of a pre-selected source material of interest, e.g. grass pollen or pollen of various species and genus.
Therefore, in preferred embodiments of the invention, the antigen is unrelated to the “triggering” allergen(s) in the sense that the antigen cannot, at least in detectable levels, bind to IgE antibodies, such as serum antibodies, obtained from a group of individuals having specific IgE antibodies, such as serum IgE antibodies against said allergen(s).
Specific IgE antibodies against an allergen may be tested by well known methods in the art, such as by use of the RAST test that is a radioimmunoassay test to detect specific IgE antibodies against suspected or known allergens. In such test the suspected allergen is bound to an insoluble material and the patient's serum is added. If the serum contains antibodies to the allergen, those antibodies will bind to the allergen. Radiolabeled anti-human IgE antibody is added where it binds to those IgE antibodies already bound to the insoluble material. The unbound anti-human IgE antibodies are washed away. The amount of radioactivity is proportional to the serum IgE for the allergen. In recent years a more superior test named the ImmunoCAP Specific IgE blood test, which in the literature may also be describe as: CAP RAST, CAP FEIA (fluorenzymeimmunoassay), and Pharmacia CAP. The quantitatively detection limit of such test may be as low as about 0.1 kU/I. For use in the context of the present invention, the quantitative detection limit may be below 1 kU/I, such as below 0.5 kU/I, such as below 0.3 kU/I where the ImmunoCAP® Specific IgE blood test or a comparable test is used.
Preferably, the antigen is unrelated to said allergen(s) in the sense that the individual in need of treatment and/or the group of individuals is/are tested negative for specific IgE antibodies, such as serum IgE antibodies, capable of binding to the antigen. That is to say that the IgE antibodies are at least not detectable or at least not present in quantifiable levels.
Obviously, the antigen might also differentiate from the allergen(s) in the sense that the antigen cannot induce a hypersensitivity immune reaction in the individual in need of treatment and/or the group of individuals. As such, in some embodiments of the invention, the antigen is unrelated to the allergen(s) in the sense that the antigen cannot initiate an immediate skin reaction in the individual in need of treatment and/or the group of individuals upon conducting skin prick testing with various concentrations of the antigen.
Also in still other further embodiments of the invention, the antigen is unrelated to the allergen(s) in the sense that the antigen cannot induce histamine release in an in-vitro basophil/mast cell assay using blood from the individual to be treated or in from a group of individuals.
As mentioned, in some embodiments of the invention, the antigen is unrelated to an allergen defined by the IgE antibodies obtained from a group of individuals rather than from the individual to be treated. A representative amount of such a group may vary. It is though anticipated that a group of individuals consist of a number of individuals of at least 4 individuals, such as of at least 5, 10, 15, 20, 30, 40, 50 or at least 100 individuals. Where it is desirable to select an antigen for use in treatment of a greater group of individuals, the antigen might be different from all sensitizing allergens or cross-reacting allergens thereof to which a group of patients have specific IgE antibodies raised against. Here it might be relevant to test a group of patients of at least 30 patients, more preferably 40, even more preferably 50 individuals. Thus, in interesting embodiments of the invention, a group of individuals have a number of individuals in the range of 30 to 1000 individuals, such as of 30 to 500, such as of 30 to 400, such as of 30 to 300, such as of 30 to 250, such as of 30 to 100.
Also, an unrelated antigen may be identified by determining whether the antigen has a distinct antigenic determinant in relation to the allergen, such as sharing B-cell and/or T-cell epitopes, including conformational epitopes and linear epitopes, with the allergen in question. Therefore, in preferable embodiments of the invention, the antigen is unrelated to said allergen(s) in the sense that the antigen does not share any B-cell or T-cell epitopes with said allergen(s). Epitopes can be “mapped,” the process of identifying and characterizing the minimum molecular structures that are able to be recognized by the immune system, according to methods known in the art, e.g. protein microarrays, ELISPOT or ELISA techniques, etc. In some embodiments, T cell epitopes which bind to MHC class II molecules are mapped with the use of Tetramer Guided Epitope Mapping (TGEM). See U.S. Pat. No. 7,094,555 to Kwok et al., which is incorporated by reference herein in its entirety. Epitopes may also be predicted based upon computer modeling, e.g., the TEPITOPE program. See, e.g., Kwok et al., Trends in Immunology, 2001, 22(11): 583-588.
Therefore, in preferable embodiments of the invention, the unrelated antigen has an amino acid sequence having less than 70% identity, preferable less than 65, 60, such as less than 65, less than 60%, less than 55%, such as less than 50%, such as less than 45%, such as less than 40% identity, such as less than 30%, such as less than 25%, such as less than 20% identity to the amino acid sequence of the allergen.
Furthermore, an unrelated antigen for use in the present invention may preferable not, such as must not bind to IgE antibodies, such as serum IgE antibodies, obtained from the individual to be treated.
Also the unrelated antigen does not bind, at least not in detectable levels, to IgG antibodies, e.g. rabbit anti IgG, raised after immunization of an animal with one or more or all allergen(s) of a pre-selected source material.
As a proteineous antigen, the unrelated antigen inherently possesses immunogenic properties and is recognized by the individual's immune system as foreign. Thus, an unrelated antigen is capable of inducing specific IgG antibodies, such as IgG4 or IgG1 antibodies, IgM or IgA antibodies capable of binding specifically to the unrelated antigen depending on the route of exposure/administration.
The unrelated antigen is a protein by nature, including a glycoprotein, a lipoprotein and post-translational derivatives thereof e.g. phospho-proteins. The unrelated antigen may also be provided as an immunogenic peptide, including a glycopeptide, a lipopeptide and post-translational derivatives thereof e.g. phospho-peptides, provided that this peptide is not identical or homologous to a peptide fragment of an allergen.
Also, in more preferred embodiments of the invention, the unrelated antigen is a water-soluble antigen. In still more interestingly embodiments of the invention, the unrelated antigen is extractable from an aqueous solution having pH in the range of 6 to 8, such as particularly in the range of 6.5 to 7.5, optionally with the presence of saline and/or presence of relevant enzymes. For example, in interesting embodiments of the present invention, the antigen is extractable from an aqueous solution, such as an aqueous saline solution having pH in the range of 6 to 8, such as preferably in the range of 6.5 to 7.5 for a period not exceeding 60 minutes, such as preferably not exceeding 45, 30, 20, 15, 10 or 6 minutes.
According to the invention, the antigen of the invention is unrelated to the allergen triggering the hypersensitivity immune response. Generally, not all of the allergens of an allergen-containing source material are able to trigger a hypersensitivity immune response. Usually, only major allergens are involved. That is to say that in more interesting embodiments of the invention, the antigen of the invention is unrelated to major allergens of one or more allergen-containing source materials. For example, it might be advantageous to select an unrelated antigen that is unrelated to an allergen, such as particularly an allergen present in an allergen-containing environmental source material or an allergen-containing dietary source material.
An unrelated antigen may be found in various source materials including those source materials comprising the one or more allergen(s) capable of triggering a hypersensitivity immune response in an individual in need of treatment or in a group of individuals having specific IgE antibodies, such as serum IgE antibodies, against one or more allergens of a pre-selected source material. However, preferably, the unrelated antigen cannot be obtained or derived from an allergen-containing source material comprising the one or more allergen(s) capable of triggering a hypersensitivity immune response in an individual in need of treatment or in a group of individuals.
Such allergen-containing source material may be naturally occurring source materials like an environmental source material (e.g. pollen, animal dander, venoms and latex) or a dietary source material (e.g. nuts and cereals).
An unrelated antigen found in a source material may be identified by use of well known protein separation techniques bearing in mind that proteins are easily denatured and the three-dimensional structure is easily lost. First of all, the source material comprising the allergen shall be identified. The source material may then be subjected to various extraction protocols, preferably where focus is on isolating a water-soluble unrelated antigen. For example, the unrelated antigen may be extracted from the source material comprising mainly aqueous extraction solvents. That is to say that the unrelated antigen is present in an aqueous extraction fraction of the source material, such as being eluted in an aqueous extraction solvent during chromatographic extraction and purification. Lipid extraction solvents may still be used for the purpose of defatting the source material or removing un-desirable matter. Various fractions from the extraction procedure may then be subjected to methods suitable for detecting the unrelated antigen. Crossed radio-immuno-electrophoresis (CRIE) is a suitable method for this purpose. In brief, a suitable method for providing an unrelated antigen is to provide water-soluble protein extracts of a source material, e.g. pollen, which are then separated by electrophoresis, followed by another electrophoresis through a gel containing IgG antibodies raised against the water-soluble protein extract in question. IgG antibodies can be raised by immunising rabbits. The resulting antibody: antigen complexes (Ab:Ag complexes) can then be visualized by Coomasie blue staining or be incubated with sera from pollen sensitized individuals followed by anti human IgE antibodies, in order to visualize the allergens of the pollen extract. The antigens that are not bound by IgE antibodies from patient's sera are considered to be candidates to an unrelated antigen.
Example 7 herein relates to the detection of unrelated antigens in three difference source materials, namely in grass pollen and in two different species of house dust mites. As noted, several candidates can be detected by means of the procedure outline above.
As mentioned, the unrelated antigen is preferably not derived from an allergen-containing source material, but it should be understood that an unrelated antigen of the present invention may in some embodiments be obtainable from an allergen-containing source material.
Typical examples of allergen-containing source material are among others:
More over, the unrelated antigen is unrelated to one or more of all of the allergens mentioned below:
Cla c 9m Cla c 14, Cla h 2, Cla h 5, Cla h 6, Cla h 7, Cla h 8, Cla h 9, Cla h 10, Cla h 12. Asp fl 13, Asp f 1, Asp f 2, Asp f 3, Asp f 4, Asp f 5, Asp f 6, Asp f 7, Asp f 8, Asp f 9, Asp f 10, Asp f 11, Asp f 12, Asp f 13, Asp f 15, Asp f 16, Asp f 17, Asp f 18, Asp f 22, Asp f 23, Asp f 27, Asp f 28, Asp f 29, Asp f 34, Asp n 14, Asp n 18, Asp n 25; Asp o 13, Asp o 21, Pen b 13, Pen b 26, Pen ch 13, Pen ch 18, Pen ch 20, Pen ch 31, Pen ch 33, Pen ch 35, Pen c 3, Pen c 13, Pen c 19, Pen c 22, Pen c 24; Pen c 30, Pen c 32, Pen o 18, Fus c 1, Fus c 2, Alt a 1, Alt a 3, Alt a 4, Alt a 5, Alt a 6, Alt a 7, Alt a 8, Alt a 10, Alt a 12, Alt a 13, Cand a 1, Cand a 3 and Cand b 2;
It might be summarized that typical examples of environmental source materials originating from pollen are, but not limited to
Typical examples of environmental source materials of animal origin are, but not limited to;
Typical examples of environmental source materials of fungal spores, yeast and moulds are, but not limited to—fungal spores, yeast and moulds of various species from the genus Alternaria, Aspergillus and Cladosporium;
Still other examples of environmental source material are venoms derived from insects, such as venoms from the class of insects named hymenoptera, more specifically from the insects of the family named Apidae (such as honey bees and bumble bees) and the family named Vespidae (such as wasps (the Vespula species), hornets, and paper wasps).
In particular interesting embodiments, the environmental source material is pollen of various species of the genus Ambrosia (ragweeds); of the genus Alder (Alnus); of the genus Betula (Birch); of the genus Olea (Olive Oil Tree); of the genus Cupressus (Redwoods); of the genus Juniperus (Cedar) and of the genus Phleum.
As mentioned, a source material of the invention may also be a dietary inclusive foods, feeds, drinks and industrial produced dietary's. Typical examples, on such source materials are, but not limited to, various species of nuts, such as of the tree nuts including macadamia nuts, brazil nuts, cashews, almonds, walnuts, pecans, pistachios, chestnuts, beechnuts, hazelnuts, pine nuts, gingko nuts and hickory nuts as well as industrial dietary products therof.
Other food sources are cereals containing gluten (i.e. wheat, rye, barley, oats, spelt); fish; crustaceans; egg; peanut; soybeans (soy protein, textured vegetable protein TPV, hydrolysed plant protein, hydrolysed soy protein, hydrolysed vegetable protein); milk and dairy products including lactose (milk sugar); nuts (e.g. almond (Amygdalus communis), hazelnut (Corylus avellana), walnut (Juglans regia), cashew (Anacardium occidentale), pecan nut (Carya illinoiesis), Brazil nut (Bertholletia excelsa), pistachio nut (Pistacia vera), macadamia nut, Queensland nut (Macadamia ternifolia)); celery and other foods of the Umbelliferae family; mustard; and sesame seed as well as industrial dietary products thereof.
As mentioned, the antigen of the invention is used in treatment of a hypersensitivity immune response. More particularly, the hypersensitivity immune response is associated with an allergic disease/allergic immune response, such as a type 1 or a type 4 hypersensitivity immune response.
Typical examples of diseases mediated by a hypersensitivity immune response are, but not limited to, allergic diseases like atopic dermatitis, urticaria, contact dermatitis, allergic conjunctivitis, allergic rhinitis, allergic asthma, anapylaxis, food allergy, drug allergy.
Typical examples of diseases mediated by a type 1 hypersensitivity immune reaction are, but not limited to, allergic diseases like atopic dermatitis, allergic conjunctivitis, allergic rhinitis, allergic asthma, anapylaxis, food allergy, drug allergy and hay fever.
In particularly, a hypersensitivity immune response of the respiratory tract is associated to allergic rhinitis and/or allergic asthma; a hypersensitivity immune response of the gastro-intestinal tract is associated to food allergy and a hypersensitivity immune response of the skin is associated to contact dermatitis and/or atopic dermatitis.
It is anticipated that the administration to mucosa of the oral cavity may be performed by topically delivering the antigen at the surface of an epithelia of the oral cavity from where the antigen is absorbed into the mucosa and sub mucosa. For example, the antigen is administered to the epithelia of the sublingual part including the floor of the mouth from where the antigen is absorbed into the mucosa and sub mucosa. It should be understood that in more interesting embodiments of the invention, the antigen is administered by sublingual administration.
Therefore, in still further embodiments of the invention, the antigen of the invention is administered by sublingual administration, i.e. topically to the sublingual epithelia or directly to the sublingual mucosa. As the sublingual route forms part of the oral cavity, it is also preferred to administer the unrelated antigen to the epithelia or mucosa of the oral cavity, such as by buccal administration. By buccal administration it is the intention to apply a suitable pharmaceutical formulation of the unrelated antigen on a mucosa of the oral cavity, such as the sublingual mucosa, at the upper surface of the tongue, at the gum or at the cheeks, so as to deliver the unrelated antigen to the mucosa of the oral cavity and wherein it is not the intention to deliver the unrelated antigen to the gastro-intestinal tract. Thus, in more preferable embodiments of the invention, the antigen is administered to the mucosa of the oral cavity, such as by sublingual administration, but where the individual is instructed not to swallow the unrelated antigen before a period of at least 1 minute after the administration of the unrelated antigen, such as more preferably, after 2 minutes, 3 minutes, 4 minutes, or 5 minutes of administration of the unrelated antigen.
As mentioned, the unrelated antigen of the invention might be used in the treatment of a hypersensitivity immune reaction. The dosage regimen of relevance might be one usually applied in the field of allergen specific immunotherapy, for example, in terms of selecting doses, number of doses per day, duration of treatment and frequency of administration. Thus, it might be envisaged that the unrelated antigen be administered frequently during a longer period before the desirable effect is achieved, such as administered daily to the mucosa of the oral cavity (e.g. sublingual mucosa) for a period of at least 6 months. Also it is envisaged that where the hypersensitivity immune response is caused by a seasonal allergen, the first dose may be administered before the allergen season.
It is also envisaged that the treatment is initiated by an up-dosing phase where the unrelated antigen is administered in increasingly doses during one day or with days between until a maintenance dose is achieved.
It should be understood that the unrelated antigen is the only antigen administered in the present treatment regiment to the oral cavity. In particularly, the allergen to which the individual has specific IgE antibodies towards shall not be co-administered with the unrelated antigen. Most suitable an allergen is not co-administered with the unrelated antigen at all. It should also be understood that the unrelated antigen is not administered together with a modulator of the Notch signalling pathway either as a combined preparation for simultaneous, contemporaneous, separate or sequential use for modulation of the immune system as described in WO 2004/082710.
As mentioned, it is crucial to the invention, that the individual be co-exposed to the unrelated antigen, at least at the time the individual is exposed to an allergen-containing source material comprising the allergen triggering the hypersensitivity immune response in the individual.
Accordingly, the unrelated antigen is also administered to the target organ, such as the respiratory tract, gastro-intestinal tract, or skin within a period at least coinciding partly or entirely with the individual's exposure to said source material.
The phrase “the antigen is also administered . . . within a period at least coinciding partly or entirely with the individual's exposure to a source material” is meant to designate that the unrelated antigen is administered to the target organ that is exposed to the “triggering” allergen and that the administration of the unrelated antigen shall be performed at least during the entire period of allergen exposure or it might be administered in a part of that period.
Therefore, in various embodiments of the invention, the unrelated antigen is administered to an individual in need thereof by combined administration of the unrelated antigen to the mucosa of the oral cavity and the administration of the same unrelated antigen or a variant thereof performed simultaneously, contemporaneously, separately or sequentially, in either order.
It is not considered that the unrelated antigen need not be administered to the target organ simultaneous and within the same period of time where the target organ is exposed to the allergen, e.g. to the respiratory tract, gastro-intestinal tract, or to the skin, as the time period may be adjusted to as to achieve bystander suppression. That is to say that the phrase “in a period coinciding with the exposure to” is meant to encompass that the unrelated antigen is administered just before exposure, at the start of exposure, at the end of exposure, within the entire period of exposure, almost within in the period of exposure, and now and then during the exposure. For example, the unrelated antigen is presented to the target organ few hours (1-6 hours), few days (1-4 days) or few (1-5 weeks) or few months (1-5 months) before the allerergen exposure takes place at the target organ. However, preferably, the unrelated antigen is administered to, exposed to or available at the target organ substantially within in the same period as the “triggering” allergen, such as at least simultaneously.
For example, where the allergen-containing source material is an airborne environmental source material, e.g. pollen, mite feces, mite crops, animal dander, animal hair, animal stool, that reaches the respiratory tract, the unrelated antigen might additionally be administered to the respiratory tract, such as to the nasal cavity. For example, a dosing regiment may include the administration of the unrelated antigen to the mucosa of the oral cavity, such as in the form of a sublingual tablet, and the additional administration of the unrelated antigen to the nasal cavity, such as in the form of a nasal spray or nasal drops.
Furthermore, where the allergen-containing source material is a dietary source material, e.g. food or a food-containing product, the unrelated antigen might additionally be administered to the gastro-intestinal tract, such as by ingestion or per-oral administration of a tablet or a capsule.
Likewise, where the allergen-containing source material is an environmental source material, e.g. an environmental source material associated with allergic responses of the skin (e.g. a gum or a gum-containing product), the unrelated antigen might additionally be administered to the skin, such as in the form of a crème, paste, gel or plaster.
It should also be understood that the additional administration of the unrelated antigen to the respiratory tract, gastro-intestinal tract, or skin need not be limited to the period of exposure to the allergen, but may additionally take place out-site the period of exposure to the allergen triggering the hypersensitivity immune response.
It is anticipated that in such embodiments, where the unrelated antigen is administered to the mucosa of the oral cavity as well as to either; the respiratory tract, gastro-intestinal tract or skin, this might be performed simultaneously, contemporaneously, separately or by sequentially administering, in either order: i) a therapeutically effective amount of an unrelated antigen to the oral cavity; and ii) an effective amount of the same unrelated antigen or an variant thereof to either the gastro-intestinal tract, gastro-intestinal tract of skin. At least it might be envisaged that the first step in treatment or prophylactic treatment ofis the administration of the unrelated antigen to the mucosa of the oral cavity. Furthermore, the additional administration of the unrelated antigen to the respiratory tract, gastro-intestinal tract or skin is initiated subsequently, such as days, months or years after starting the administration of unrelated antigen to the oral mucosa. Thus, in some embodiments of the invention, the administration of the unrelated antigen to the oral cavity is initiated before the administration of the unrelated antigen to the respiratory tract, gastro-intestinal tract or skin.
It is also envisaged that the additional administration of the unrelated antigen at least be performed during the individual's exposure to the “triggering” allergen, such as during the pollen season or when ingesting allergen-containing foods. It is also envisaged that the additional administration of the unrelated antigen be continued after the administration of the unrelated antigen to the mucosa of the oral cavity has stopped. Thus, in various embodiments of the invention, the administration of the unrelated antigen to the respiratory tract, gastro-intestinal tract, or skin at least be performed during the individual's exposure to an allergen-containing source material of interest, such as to an allergen to which the individual is sensitized to, such as to an allergen triggering a hypersensitivity immune response in the individual or in a group of individuals of interest; the administration of the unrelated antigen to the respiratory tract, gastro-intestinal tract, or skin is initiated in the period of administering the unrelated antigen to the oral cavity and continued after the administration to the oral cavity has stopped; the administration of the unrelated antigen to the oral cavity is performed daily, twice weekly, weekly or twice a month; and/or the administration of the unrelated antigen to the respiratory tract, gastro-intestinal tract, or skin is performed daily, twice weekly, weekly or twice a month.
In interesting embodiments of the invention, the unrelated antigen is administered to the oral cavity, such as by sublingual administration, such as by sublingual administration of a tablet (including fast-disintegrating tablet, freeze-dried tablet) and the same unrelated antigen or a variant thereof is administered to the nasal cavity in the form of a nasal spray or nasal drops.
Slightly differences between unrelated antigen for administration to oral cavity versus administration to the respiratory tract, gastro-intestinal tract or skin. It should also be considered that the unrelated antigen as administered to the respiratory tract, gastro-intestinal tract or skin need not be identical to unrelated antigen administered to the oral cavity. Thus, in some embodiments of the invention, the unrelated antigen that is administered to the respiratory tract, gastro-intestinal tract or skin is a variant of the unrelated antigen of the unrelated antigen administered to the oral cavity or vice versa. However, still preferably, the unrelated antigen used in the step of administering the unrelated antigen to the oral cavity is the same as the unrelated antigen used in the administration of unrelated antigen to the respiratory tract (e.g. nasal cavity), gastro-intestinal tract (e.g. per-oral administration or by ingestion) or to the skin.
However, it is considered that the variant of the unrelated antigen is chemical modified or biologically modified so as to modify its solubility properties, bioavailability properties or stability. Examples are antigen variants with chemical modifications, such as N- or O-linked glycosylation or derivatizing of the N-terminus or of thiol groups of the unrelated antigen. Other examples are antigen variants that are biologically modified, such as by post-translational modifications, such as for example; glycosylation, acetylation, alkylation (methylation, ethylation), biotinylation, glutamylation, glycylation, isoprenylation, lipoylation, phosphopantetheinylation, phosphorylation, sulfation, selenation and C-terminal amidation.
It should be understood that the variant has significant homology or identity to the original unrelated antigen, such as at least 50 percent, 55 percent, 60 percent, 65 percent, 70 percent, 75 percent, 80 percent, 85 percent, 90 percent, 95 percent, 98 percent and/or 100 percent homology or identity with the amino acid sequence of the unrelated antigen administered to the oral cavity.
Exemplary protein variants may be a substitution variant, deletion variant, duplication variant, insertion variant, insertion-deletion variant or frame shift variant or any other suitable variant.
For example, the variant has no more than 30% of the amino acids of the unrelated antigen as administered to the oral cavity subjected to substitution, deletion, duplication, insertion, or a mixture thereof. More preferably no more than 25%, such as even more preferably no more than 20%, such as no more than 15%, such as no more than 10%, such as no more than 5% of the amino acids of the originally detected unrelated antigen are subjected to substitution, deletion, duplication, insertion, or a mixture thereof. Also it is anticipated that a variant of the unrelated antigen that is administered to the oral cavity has less than 20%, such as less than 15%, less than 10, 8, 6, 5, 4, or 3% amino acids subjected to derivatization, such as glycosylation, acetylation, alkylation (methylation, ethylation), biotinylation, glutamylation, glycylation, isoprenylation, lipoylation, phosphopantetheinylation, phosphorylation, sulfation, selenation and C-terminal amidation.
Where the antigen exhibits poor stability to the gastric juice, the unrelated antigen is preferably administered in a form avoiding the contact to the gastric juice, such as in a form preventing the degradation of the unrelated antigen in the gastric juice. This may be accomplished by incorporating the unrelated antigen in pharmaceutical formulations resistant to the gastric juice or by incorporating other pharmaceutical delivery techniques able to avoiding the degradation of proteins in the gastric fluid.
The antigen of the invention may be formulated together with therapeutically inactive ingredients and/or immune-modifying agents like adjuvants. Typically, the formulation is a solid dosage form, such as a fast-disintegrating tablet or a liquid including a solution, a suspension, a dispersion, a gelled liquid. Alternatively, the formulation is an emulsion or a re-dissolvable powder, granulate or lyophilisate, which can be dissolved to form a liquid before being administered.
Excipients for use in formulations are well-known to the person skilled in the art and include solvents, emulsifiers, wetting agents, plasticizers, colouring substances, fillers, preservatives, viscosity adjusting agents, buffering agents, pH adjusting agents, isotonicity adjusting agents, mucoadhesive substances, and the like. Examples of formulation strategies are well-known to the person skilled in the art.
The adjuvant may be any conventional adjuvant, including oxygen-containing metal salts, e.g. aluminium hydroxide, chitosan, heat-labile enterotoxin (LT), cholera toxin (CT), cholera toxin B subunit (CTB), polymerised liposomes, mutant toxins, e.g. LTK63 and LTR72, microcapsules, interleukins (e.g. IL-1 BETA, IL-2, IL-7, IL-12, INFGAMMA), GM-CSF, MDF derivatives, CpG oligonucleotides, LPS, MPL, phosphophazenes, Adju-Phos(R), glucan, antigen formulation, liposomes, DDE, DHEA, DMPC, DMPG, DOC/Alum Complex, Freund's incomplete adjuvant, ISCOMs(R), LT Oral Adjuvant, muramyl dipeptide, monophosphoryl lipid A, muramyl thpeptide, and phospatidylethanolamine.
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Prophylactic Treatment of Naïve mice with an unrelated antigen.
An extract of grass pollen of the species phleum pratense (Phl p) is obtained by extracting defatted grass pollen with an aqueous saline solution.
Female, 6-10 week-old BALB/cJ mice were bred in-house and maintained on a defined diet not containing component cross reacting with antisera to Phl p. Each experimental group consisted of 8 animals.
Naïve mice received sublingual immunotherapy (SLIT) with 40 μg Phl p extract or buffer for two weeks before being immunized to raise an immune response against another antigen. SLIT was performed by holding the scruff of the mice and carefully applying 5 μl of allergen solution under the tongue. The mice were held by the scruff for additional 20 seconds to prevent the animal from swallowing the allergen solution. The mice were then challenged by intraperitoneal injection of either 8 μg Phl p extract mixed with 250 μg chicken ovalbumin (OVA) adsorbed to aluminium hydroxide or of OVA alone adsorbed to aluminium hydroxide so as to develop an immune response. Ten to twelve days later the mice were euthanized, spleens were removed and cells were set up in an in vitro re-stimulation assay. In this assay, cells were stimulated with the antigen triggering an immune response (OVA) in order to evaluate the effect of SLIT treatment of mice with the unrelated antigens present in the Phl p extract on the development of an OVA specific immune response. In alternative experiments mice were SLIT treated with OVA and intraperitoneally injected with Phl p extract mixed with OVA or Phl p extract alone. Following euthanization, spleen cells were re-stimulated by Phl p to evaluate the effect of the sublingual pre-treatment with OVA on the Phl p specific immune response. The experimental outline is depicted in
Spleens were teased into single cell suspension and washed three times in medium. Cells were counted and adjusted to 1.67×106 cells/mL. 3×105 cells were added to each well of a 96 well flat-bottomed culture plate and the cells were stimulated by 0, 5, 25 and 125 μg/mL OVA. The cells were cultured for 6 days at 37° C. and 5% CO2. Proliferation was measured by adding 0.5 μCi of 3H-thymidine to each well for the last 18 hours of the culture period, followed by harvesting the cells and counting the incorporated radiolabel.
Spleens were teased into single cell suspension and washed three times in medium. Cells were counted and adjusted to 3×106 cells/mL. 5×106 cells were added to each well of a 96 well culture plate and the cells were stimulated by 0 and 125 μg/mL OVA. Supernatants were harvested at day 5 and analyzed for the presence of the cytokines IL-4 and IL-5 using a Mesoscale mouse Th1/Th2 ELISA kit.
SLIT Treatment with Phl p
SLIT Treatment with OVA
Together these data demonstrate that suppression of an immune response (characterized by Th2-cytokines) by SLIT treatment of the mice with an antigen unrelated to the antigen triggering the immune response can be obtained, regardless whether OVA or Phl p extract served as model antigens of the unrelated antigen.
Phl p, an extract of grass pollen of the species phleum pratense is obtained by extracting defatted grass pollen with an aqueous saline solution.
Female, 6-10 week-old BALB/cJ mice were bred in-house and maintained on a defined diet not containing component cross reacting with antisera to Phl p. Each experimental group consisted of 8 animals.
Naïve mice were treated daily with 40 μg Phl p extract either by the sublingual or the peroral (intragastric gavache) route for two weeks. The mice were then immunized to raise an immune response against another antigen by intraperitoneal injection. This injection consisted of 8 μg Phl p extract mixed with 250 μg ovalbumin (OVA) adsorbed to aluminium hydroxide. Ten to twelve days later the mice were euthanized, spleens were removed and cells were set up in an in vitro re-stimulation assay. In this assay the cells were stimulated with OVA in order to evaluate the effect of SLIT treatment of with the unrelated antigen Phl p on the OVA specific immune response. The experimental outline is depicted in
Spleens were teased into single cell suspension and washed three times in medium. Cells were counted and adjusted to 1.67×106 cells/mL. 3×105 cells were added to each well of a 96 well flat-bottomed culture plate and the cells were stimulated by 0, 5, 25 and 125 μg/mL OVA. The cells were cultured for 6 days at 37° C. and 5% CO2. Proliferation was measured by adding 0.5 μCi of 3H-thymidine to each well for the last 18 hours of the culture period, followed by harvesting the cells and counting the incorporated radiolabel.
As seen in
Phl p, an extract of grass pollen of the species phleum pratense is obtained by extracting defatted grass pollen with an aqueous saline solution.
Female, 6-10 week-old BALB/cJ mice were bred in-house and maintained on a defined diet not containing component cross reacting with antisera to Phleum pratense (Phl p). Each experimental group consisted of 8 animals.
Naive mice were treated by sublingual immunotherapy (SLIT) with 40 μg Phl p extract for 2 weeks. Subsequently, the mice were immunized by three weekly i.p. injections of either a mix of 10 μg OVA and 8 μg Phl p extract or 10 μg OVA alone adsorbed to aluminium hydroxide. Subsequently, the mice were challenged intranasally (IN) with 50 μg of OVA for four days so as to induce clinically relevant readouts of a Th2-driven immune response. The mice were sacrificed one day after the last challenge and blood, bronchoalveolar fluid (BAL), spleen and cervical lymph nodes were collected for analysis. The experimental outline is depicted in
Clinically relevant readouts, such as airway hyper-reactivity and the fraction of eosinophils, were obtained on the last day of IN challenge.
Airway hyper-reactivity: Using a whole body pletysmograph, airflow obstruction was induced by challenging the mice with increasing concentrations of aerosolized metacholine. Pulmonary airflow obstruction was measured by enhanced pause (penh) in a period of 6 minutes after administration of metacholine. Differential counting of BAL fluid: The BAL fluid was centrifuged and the supernatant was removed. The pellet was re-suspended in PBS and the fraction of eosinophils was determined by an automated cell counter (Sysmex).
Spleens were teased into single cell suspension and washed three times in medium. Cells were counted and adjusted to 1.67×106 cells/mL. 3×105 cells were added to each well of a 96 well flat-bottomed culture plate and the cells were stimulated by 0, 5, 25 and 125 μg/mL OVA. The cells were cultured for 6 days at 37° C. and 5% CO2. Proliferation was measured by adding 0.5 pCi of 3H-thymidine to each well for the last 18 hours of the culture period, followed by harvesting the cells and counting the incorporated radiolabel.
By these experiments, the inventors wanted to examine whether the prophylactic SLIT treatment also had an effect on allergic asthma. In short, naïve mice were SLIT treated with an unrelated antigen (Phl p) or with buffer prior to the induction of allergic asthma. The asthma was induced by first immunizing the mice by i.p. injection with OVA (antigen triggering the immune response) and Phl p together versus OVA alone, followed by intranasal challenge with the same OVA. As demonstrated by the results depicted in
The data in this series of experiments show that prophylactic SLIT treatment with an unrelated antigen suppresses clinically relevant readouts of allergic asthma in mice.
Treatment of Sensitized Mice with an Unrelated Antigen to Reduce Clinical Relevant Symptoms on a Hypersensitivity Immune Response
Phl p, an extract of grass pollen of the species phleum pratense is obtained by extracting defatted grass pollen with an aqueous saline solution.
Female, 6-10 week-old BALB/cJ mice were bred in-house and maintained on a defined diet not containing component cross reacting with antisera to Phleum pratense (Phl p). Each experimental group consisted of 8 animals.
In one set of experiments mice were sensitized by three weekly i.p. injections of 8 μg Phl p extract adsorbed to aluminium hydroxide. Subsequently, the mice were treated by sublingual immunotherapy (SLIT) with 250 μg OVA for 4 weeks, followed by 2 weeks of intranasal challenge with 8 μg Phl p together with 10 μg OVA or Phl p alone. The experimental outline is depicted in
In another set of experiments, mice were sensitized by two weekly i.p. injections of 10 μg OVA adsorbed to aluminium hydroxide. Following this, the mice were SLIT treated with 40 μg Phl p for 4 weeks and subsequently they were intra-nasally challenged for 4 days with 100 μg OVA together with 8 μg Phl p or with 8 μg OVA alone. The experimental outline of this is depicted in
In both sets of experiments, the mice were sacrificed one day after the last challenge and blood, bronchoalveolar fluid (BAL), spleen and cervical lymph nodes were collected for analysis.
Clinically relevant readouts, such as sneezes, airway hyper-reactivity and presence of eosinophils, were obtained on the last day of IN challenge.
Sneezing: The mice were observed in an 8 min-period after intranasal administration of Phl p and the numbers of sneezes were counted during this period.
Airway hyper-reactivity: Using a whole body pletysmograph, airflow obstruction was induced by increasing concentrations of aerosolized metacholine. Pulmonary airflow obstruction was measured by enhanced pause (penh) in a period of 6 minutes after administration of metacholine.
Differential counting of BAL fluid: The BAL fluid was centrifuged and the supernatant was removed. The pellet was re-suspended in PBS and the fraction of eosinophils was determined by an automated cell counter (Sysmex).
Suppression Induced by SLIT Treatment with Phl p
In this set of experiments the inventors wanted to investigate if SLIT treatment with one antigen (Phl p) could prevent clinical signs of asthma induced by another antigen (OVA) in a mouse animal model of asthma. As shown in
Suppression Induced by SLIT Treatment with OVA
In this set of experiments, the inventors investigated if SLIT treatment with an unrelated antigen (OVA) could prevent clinical and immunological signs of asthma induced by another antigen (phl p) in a mouse animal model of rhinitis. In the rhinitis model employed, the primary clinical read-out is the number of sneezes. As shown in
In summary, these results show that it is possible to suppress a clinically relevant readout of allergic rhinitis in mice pre-sensitized to an antigen by SLIT treatment of the mice with an unrelated antigen provided the mice are exposed to both the antigen triggering the allergic rhinitis and the unrelated antigen upon challenging respiratory organ of the mice to the triggering antigen.
Treatment of Sensitized Mice with an Unrelated Antigen to Reduce Clinical Relevant Symptoms on a Hypersensitivity Immune Response
Phl p, an extract of grass pollen of the species phleum pratense is obtained by extracting defatted grass pollen with an aqueous saline solution.
Female, 6-10 week-old BALB/cJ mice were bred in-house and maintained on a defined diet not containing component cross reacting with antisera to Phleum pratense (Phl p). Each experimental group consisted of 8 animals.
Animal experiments
Mice were sensitized by two weekly i.p. injection of 10 μg OVA adsorbed to aluminium hydroxide. Following this, the mice were SLIT treated with 40 μg Phl p for 4 weeks and subsequently they were intra-nasally challenged for 4 days with 50 μg OVA together with 8 μg Phl p or with OVA alone. At the last day of the intranasal challenge, airway hyperresponsiveness was measured using whole body plethysmography. The mice were sacrificed one day after the last challenge and blood, bronchoalveolar fluid (BAL), spleen and cervical lymph nodes were collected for analysis. The experimental outline is depicted in
Clinically relevant readouts, such as airway hyper-reactivity and presence of eosinophils, were obtained on the last day of IN challenge.
Airway hyper-reactivity: Using a whole body pletysmograph, airflow obstruction was induced by increasing concentrations of aerosolized metacholine. Pulmonary airflow obstruction was measured by enhanced pause (penh) in a period of 6 minutes after administration of metacholine.
Differential counting of BAL fluid: The BAL fluid was centrifuged and the supernatant was removed. The pellet was re-suspended in PBS and the fraction of eosinophils was determined by an automated cell counter (Sysmex).
In this set of experiments, the inventors wanted to confirm the results of Example 4.
As observed
Taken together, these results confirm the results of Example 4, and thereby strengthen the observation that an allergic immune response can be suppressed by treatment of pre-sensitized mice with an unrelated antigen.
Prophylactic Treatment of Naïve Mice with an Unrelated Antigen so as to Reduce a Hypersensitivity Immune Response.
Female, 6-10 week-old BALB/cJ mice were bred in-house and maintained on a defined diet not containing component cross reacting with antisera to Phleum pratense (Phl p). Each experimental group consisted of 8 animals.
Naive mice were treated by sublingual immunotherapy (SLIT) with 50 or 200 μg Phl p 5 for 2 weeks, followed by three weekly i.p. injections of either a mix of 10 μg OVA and 10 μg Phl p 5 adsorbed to aluminium hydroxide. Subsequently, the mice were challenged intranasally with 50 μg of OVA for four days. The mice were sacrificed one day after the last challenge and blood, bronchoalveolar fluid (BAL), spleen and cervical lymph nodes were collected for analysis. The experimental outline is depicted in
Clinical data were obtained 24 hours after the last day of IN challenge. Differential counting of BAL fluid: The BAL fluid was centrifuged and the supernatant was removed. The pellet was re-suspended in PBS and the fraction of eosinophils was determined by an automated cell counter (Sysmex).
Spleens were teased into single cell suspension and washed three times in medium. Cells were counted and adjusted to 1.67×106 cells/mL. 3×105 cells were added to each well of a 96 well flat-bottomed culture plate and the cells were stimulated by 0, 5, 25 and 125 μg/mL OVA. The cells were cultured for 6 days at 37° C. and 5% CO2. Proliferation was measured by adding 0.5 μCi of 3H-thymidine to each well for the last 18 hours of the culture period, followed by harvesting the cells and counting the incorporated radiolabel.
In this experiment, the results of example 3 are confirmed using a single antigen for the induction of tolerance by the SLIT treatment instead of the Phl p extract used in example 3. This was done by SLIT treatment of naïve mice with Phl p 5 or buffer. After the SLIT treatment allergic asthma was induced by an IP challenge with OVA and Phl p 5 together or OVA alone, followed by intranasal challenge with OVA. As seen in
The data in this experiment show that prophylactic SLIT treatment with a single antigen induces bystander tolerance that has an effect on the clinical read-outs of a subsequently induced allergic asthma.
A number of antigens (unrelated antigen) that do not bind to sera of allergic patients were detected in pollen allergen extracts or mite allergen extracts by crossed radio immunoelectrophoresis (CIE).
Aqueous extracts of pollen allergens of Phleum Pratense (Phl p) or of mite (Dermatophagoides pteronyssinus (Der p) and Dermatophagoides farinae (Der f) allergens (mite bodies and culture medium) were prepared by the following extracting procedure:
Extraction 1:10 are carried out as follows; 1 g of pollen (Phl p) or 1 g of mite bodies+mite culture (Der p or Der f) were suspended in 10 ml of aqueous solution of 0.125 M NH4HCO3 and 15 mM NaN3 and left overnight at +5° C. under stirring. The suspension was centrifuged at 27.000 g for 30 minutes at +5° C. followed by filtration, if necessary. The precipitate was discarded. The extract was dialysed 3×4 hrs against 5 mM NH4HCO3 followed by 4 hrs against purified water. The volume of dialysis water was 20-50 times the volume in the dialysis bag. The dialysed extract is then lyophilised at −80° C. and stored in an air tight container at −20° C.
Sera of 21 grass allergic patients and 21 mite (Der p and/or Der f) allergic patients were collected, respectively. Sera of allergy class≧2 were included in the study. Patients had a positive skin prick test and/or presence of IgE antibodies towards the allergens of Phl p and of mites (Der f and Der p), respectively.
Sera containing polyclonal IgG antibodies were produced by immunising rabbits (3-4 months old that never have been immunised before) with the aqueous allergen extracts of Phl p and mites (Der p and Der f), respectively. Sera is collected from coagulated blood and 0.09% NaN3 is added.
One crossed immunoelectrophoresis is performed for each individual serum by adding the aqueous allergen extract of Phl p or Der p of Der f and respective rabbit antibodies to precipitate the antigens to a CIE plate. The plates were dried in cold air and incubated overnight in small boxes with 300 μl patient serum +7700 μl phosphate buffer. The plates were washed 4×10 minutes with 0.9% NaCl and incubated overnight with I125-antiIgE (Pharmacia), 300.000 cpm/plate in a total volume of 8 ml. After washing (4×10 min with NaCl) the plates were dried and placed in an X-ray cassette, gel-side up and an X-ray film (Retina) on top. The film was exposed at −80° C. for 1 day, 3 days and 10 days. The CIE-plates are stained (Coomassie-staining) and each autoradiography was labeled and cut out.
All precipitates (radioactive+non-radioactive precipitates) are detected, scored and numbered. The radioactively stained precipitates are antigens capable of binding to IgE of patient sera and are then allergens, which may be scored by assigning a score of 3 if a precipitate is visible after 1 day (strong), score 2 if visible after 3 days (moderate) and score 1 if visible after 10 days (weak). Precipitates with no radioactive staining of precipitates are antigens not recognised by IgE antibodies of allergic patients and represents unrelated antigens of the present invention.
An Allergogram is drawn using the precipitate numbers from the reference picture and the number of patients reacting to each precipitate.
A total of 30 precipitates are visible of which 22 are recognised as allergens and 8 are unrelated antigens of the invention. A CIE diagram (51-990282) is shown in
A total of 24 precipitates are visible of which 19 are recognised as allergens and 5 are unrelated antigens of the invention. A CIE diagram is shown in
A total of 22 precipitates are visible of which 16 are recognised as allergens and 6 are unrelated antigens of the invention. A CIE diagram is shown in
Thus, unrelated antigens are found in various allergen sources. Further identification of the unrelated antigen may be accomplished by well-known techniques in the art including purifying the precipitate and conducting mass spectrometry analysis.
It will be investigated if SLIT also has a bystander effect in a mouse model of Atopic Dermatitis. For example, allergens obtainable from latex will be used as the “triggering” allergen.
Atopic Dermatitis will be induced according to the model developed by Spergel et al (1999) and by Jin H et al (2009). In brief, mice will be sensitized epicutaneously by tape stripping the skin and adminstration of OVA secured by sterile gauze and a bioocclusive dressing. The mice will receive a total of three one week exposures separated by 2 week intervals.
The degree of atopic dermatitis will then be evaluated by obtaining specimens from the patched areas of the skin 24 h after the patch from the third sensitization has been removed.
The specimens will be used for histological analyses to evaluate the thickening of the dermis and epidermis as well as the cellular influx (e.g. eosinophils).
Furthermore, the specimens will be stained for cellular markers such as CD3, CD4 and CD8 by immunohistochemistry in order to measure the celluler influx of immune cells. Finally, blood will be collected and cytokines measured using a mesoscale TH1/TH2 ELISA kit.
The effect of SLIT will be investigated in this model by either prophylactic SLIT treatment or by SLIT treatment after the first or second cutaneous administrations of OVA with an antigen non-related to OVA (e.g. Phl p or latex allergen).
It will be investigated if SLIT also has a bystander effect in a mouse model of food allergy.
Food allergy will be induced according to the model described by Dunkin et al (2011). In brief, mice will be epicutaneously sensitized by administration of 0,1 mg OVA in 50 μL on the abdominal skin of anesthetized mice. The sensitization procedure will be repeated weekly for 6 times. One week after the last sensitization the mice will be orally challenged by increasing oral doses of OVA and symptoms of anaphylaxis as well as body temperature will be recorded every 10 minutes. In addition to the clinical read-outs mentioned above, blood will be collected from the mice following the oral challenge and specific IgE will be measured in serum. Finally, T-cell reactivity in spleen and local draining lymph nodes will also be measured.
The effect of SLIT will be investigated in this model by either prophylactic SLIT treatment prior to the sensitization or by SLIT treatment after the sensitization procedure, with an antigen non-related to OVA (e.g. Phl p or a peanut allergen).
| Number | Date | Country | Kind |
|---|---|---|---|
| 10187744.7 | Oct 2010 | EP | regional |
| 11157868.8 | Mar 2011 | EP | regional |
| Number | Date | Country | |
|---|---|---|---|
| 61393460 | Oct 2010 | US |
