Editor-in-Chief Hatice Kübra Elçioğlu Vice Editors Levent Kabasakal Esra Tatar Online ISSN 2630-6344 Publisher Marmara University Frequency Bimonthly (Six issues / year) Abbreviation J.Res.Pharm. Former Name Marmara Pharmaceutical Journal
Journal of Research in Pharmacy 2010 , Vol 14 , Num 3
Animal models of asthma
Tunç Akkoç
Marmara University, Pediatric Allergy and Immunology Department, İstanbul, Türkiye DOI : 10.12991/201014444


Astım, allerjik rinit, ve ekzema gibi allerjik hastalıların prevelansı özellikle batılı ülkelerde popülasyonun yaklaşık %15'ini etkileyecek şekilde artmaktadır. Bu hastalıklar arasında astım havayollarının inflamatuar bir hastalığıdır ve hastalığın altında yatan fizyolojik ve immunolojik mekanizmalar halen tam olarak açıklanamamıştır. Farelede geliştirilen astım modeli insan astımına çok benzemektedir. Bu yüzden geliştirilen uygun modellerde hem hastalık mekanizması hakkında hem de tedavi yakalşımları hakkında önemli veriler elde edilebilmektedir. Bu derlemede, astım için geliştirilen hayvan modelleri ve tedavi yaklaşımları tartışılmıştır.


The prevelance of allergic diseases such as allergic asthma, allergic rhinitis, atopic dermatitis and food allergy are rapidly increasing mostly in Westernized countries, with the prevelance over %30 in childhood [1]-[2]. Human allergic asthma is a chronic inflammatory disorder of the airways and is chracterized by airway inflammation, persistent airway hyperresponsiveness (AHR) and intermittent, reversible airways obstruction [3]. Additional histopathological features of asthma are structural changes in airways including subepithelial and airway wall fibrosis, goblet cell hyperplasia/ metaplasia, smooth muscle thickening and increased vascularity, that are shown not to be reversed by corticosteroids [4]-[5]. These structural changes referred as ‘airway remodelling’ and result with repeated exposure to allergen, that lead to chronic inflammation in the airways [6].

Although, today there are several therapeutic and preventive approaches disscussing for allergic asthma, there is still important part left to be understood. Because of the ethical reasons, clinal studies with allergic individuals limited and experimental murine models became more important for drug treatment studies.

Animal models, especially mouse models, have been developed for almost all allergic disease as asthma [7], allergic rhinitis [8], food allergy and anaphylaxis [9], atopic dermatitis [10], and allergic conjunctivitis [11]. These murine models are important in order to examine the mechanism of the disease, the activiy of a variety of genes and cellular patways, and to predict the safety of new drugs or chemicals before being used in clinical studies [12]. As a result, animal models have been developed to study pathogenesis of the diseas including genetic factors, to define the pathogenic pathways and suggest new therapeutic views [13]. This review focuses on the murine models of asthma and disscusses current therapeutic approaches carried on mouse models of asthma.

Immune response to allergens
In the case of immune tolerans cannot be established to certain allergens such as, aeorallergens foods and insect venom, leads to induction of type I hypersensitivity reactions. Several factors including genetic susceptibility, the nature of antigen that initiates the disease (antigen dose time of exposure, route of exposure, and structural characteristics), and challenge with infections and bacteria, [14] influence the type of immune response.

The initial event responsible for the development of allergic disease is the generation of allergenspecific CD4+T helper cells. Depending on the stimulus, naive T cells can differentiate into Th1 Th2, Th17 or recently suggested Th9 effector cells. Based on these T-cell subsets can promote different types of inflammatory responses. The current view is that with the IL-4 stimulation in an appropriate conditions, naive T cells easly differentiate into T helper (Th) 2 cells [15]-[16]. Once Th2 response is established, further allergic immune response may establihed in two main phas es: first sensitization and development of memory and later followed by effector phase and tissue injury. In sensitization phase, CD4+Th2 cells secrete IL-4, IL-5 and IL-13 and mediate several regulatory and effector functions. These cytokines induce class switching of antibody isotypes to the e heavy chain for IgE antibody production by B cells, development and recruitment of eosinophils, production of mucus and contraction of smooth muscles [15]-[17]. Later, this allergen specific IgE binds to high affinity receptor for IgE (FceRI receptors) on the surface of mast cells and basophils. These series of activation lead to the sensitization of the patients to a specific allergen. In the final phase, upon the re-exposure to sensitized allergens effector cells are activated and tissue injury happens. Here, the degranulation of basophils and mast cells by IgE mediated by crosslinking of receptors that is the crucial event in the type I hypersensitivity, which may lead to chronic allergic inflammation. All these events require allergen specific T cell activation in allergic individuals and for healthy ones, peripheral T cell tolerans prevents formation of atopic immunopathology.

Click Here to Zoom
FIGURE 1: PAS stained lung sections of all groups. (40x)

Animals used in allergic asthma models Experimental studies revealed that, there is wide variety of animal models of asthma in different specicies. Mice, rats guinea pigs, dogs, sheep, monkeys and horses have been employed to study the inflammatory processes and alternations in airway function [18]-[20]. Within these animals, mice are the most common species studied in animal models of asthma. We will disscuss mouse models of asthma later in this review.

Although a majority of studies of allergic airway disease are carried out in the mouse, the guinea pig initially was utilized as an animal model of pulmonary hypersensitivity and AHR for many decades [21]. Studies with guinea pig showed increased IgG1 and IgE in response to allergen and hyperreactivity reaction due to allergen sensitization. Model studies showed, allergen sensitization require allergen inhalation. One of the benefit of the model is the lung surves as the primary target organ of type I hypersensitivity reactions to allergen. Further immediate and late phase reactions are also seen in carried asthma model. Another advantage of the asthma model with guinea pigs is the rich eosinophilic and neutrophilic pulmonary infiltration. On the other hand, one of the major disadvantage to the guinea pig is the predominance of IgG1 rather than IgE as the major anaphylactic antibody [22].

In several studies, investigators have been used another small rodent, rat, for allergic animal models. Allergen specific IgE production is predominant and plays crucial role in anaphylaxis. Once, asthma model with rat developed, there is longlasting airway hyperreactivity. Also immediate- and latephase airway responses established in the succesfull asthma model. In the comparision with guinea pig asthma model, sensitization requries injection of allergen, rather than administration via the inhalation route [23]-[24].

Click Here to Zoom
FIGURE 2: OVA-specific IgE levels.

The rabbit elicit an asthma model and lung is the target organ for anaphylactic response as humans. Moreover, both immediate- and late-phase airway responses seen with the increased IgE which is anaphylactic antibody.

Although, larger animals such as monkey, sheep and horses have been used in asthma models, they are hard to handle and too expensive in order to use on regular basis.

Mouse models of asthma
Mice are the most common species studied in animal models of asthma. In principle, mice are systemically sensitized to allergen with alum as an adjuvant via intraperitoneal injection and challenged to allergen via the airways. The nature of acute inflammatory mouse model directly influenced by the genetic background of the mice, the allergen, the sensitization and challenge protocol [6].

Genetic background of mice
In laboratory conditions, it is aviable to get various inbred mouse strains. However, it is inappropriate to develope asthma model with all these mouse strains. Based on the level of allergen-specific IgE/IgG1 production and the degree of airway inflammation following repeated airway allergen challenges high- and low- responder mouse strains were identified. Each different mouse strains show different response pattern following immunization to allergens. There are difference in the ability to induce allergic inflammation and AHR within those mouse strains. A/J and AKR/J mice bare high levels of allergen-induced AHR and reactivity to metacholine [25] while, C3H/HeJ and DBA/2 mice resistant to the development of allergen-induced AHR [26]. In many studies, either BALB/c or C57BL/6 mice were used. BALB/c mice are known as IgE-high responders to many allergens (e.g. Ovalbumin, Bet v 1) and goat anti-mouse IgDstimulation whereas C57BL/6 mice is characterized as low- IgE responder animal [27]. Supportingly, several experimental mouse models with BALB/c strain, showed well developed Ovalbumin (OVA) induced allergic immune response with allergen-specific IgE, AHR and eosinophilic airway inflammation [4]. On the other side, C57BL/6 mice exhibit Th1-dominant immune response compared to BALB/c mice.

In order to perform murine asthma model, different types of allergens may be used. Among them, OVA derived from chicken egg is a frequently used allergen that induce robust allergic pulmonary inflammation in mice [28]. There are some advantage to use OVA in models such as considerably inexpensive can be highly purified, the immunodominant epitopes have been well characterized, and recombinant peptides have been generated [29].

The way of allergen administration is important in develeoping asthma model without induction of tolerance. Especially repeated inhalation or sublingual administration of OVA induce tolerance instead of sensitization. For priming allergen sensitization, allergen should be given combined with adjuvant and via intraperitoneal injection [30]. Following sensitization a series of inhaled or intranasal challenges are administered to elicit allergic response. OVA-induced allergic airway models may not represent the same conditions experienced by asthmatics where allergen exposure may be more frequent and much longer periods of time [28]. However, OVA is seldom implicated in human asthma, and other gruops have used alternative allergen that have greater clinical relevance for example house dust mite (HDM) and cockroach extracts [31]-[32].

Sensitization and challenge protocols
Mice do not spontaneously develop AHR or allergic airway inflammation. There are many different sensitization and challenge protocols exists. Due to experimental approach, acute or chronic asthma models may be developed. Acute sensitization protocols usually requrie multiple systemic administration of allergen in the presence of an adjuvant. Aluminium hydroxide (ALOH3) is one of the best choise for adjuvant in case, it promote the development of the Th2 immune response when it is exposed to antigen. Although there are adjuvant-free protocols exist, they usually require a greater number of exposures to achive suitable sensitization [33]. Both OVA and HDM can be used as an antigen to induce pulmoner inflammation. If OVA administered via inhalation instead of systemic delivery tolerans can develop. However, inhaled delivery of HDM seems to be more successfull in developing allergy model because of intrinsic enzymatic activity of this allergen. Extracts or purified protein derived from potent human allergens including cockroach, ragweed, or fungi have been increasingly used as allergens in mice and other species [34]-[36]. After sensitization period (usually 14-21 days), allergen challenge via airways will be carried out for several days. The administration of allergen through airways may be applied by nebulization intratracheal (i.t) or intranasal (i.n.) instillation [4]. With these sensitization and challenge protocols mice develop key features of clinical asthma, as increased levels of allergen specific and total IgE, inflammatory cell infiltration to airways which referred as airway inflammation, goblet cell hyperplasia , epithelial hypertrophy, AHR to specific sensitized allergens or metacholine, early- and late-phase bronchoconstriction in response to allergen challenge [37]. (Fig. 1)

Although acute allergen challenge model develops many aspects of human asthma, there are limitations to these models in comparision with asthmatics. For this, several research groups have developed chronic allergen challenge models in order to reproduce more of the features of clinical asthma such as goblet cell metaplasia, epithelial hypertrophy, subepithelial fibrosis and limites smooth muscle hyperlasia which together refferred as airway remodelling and persistent AHR [4]-[33]. In order to develop chronic asthma model, low levels of allergen should be repeated exposure to the airways to for periods up to 12 weeks. Mostly in an experimental models, OVA has been used as an allergen [38]-[40] and in some experimental models enviromentally relevant antigens such as, HDM extract or grass polen have been used to develop chronic allegen challenge asthma model [31]-[41].

Regulatory T cells in murine models in allergic
T cells with the capacity of suppressing the unwanted immune response were first described in the beginning of 1970s [42]. Since mid-1990s, the notion of the T-cell-mediated immune suppression has been strongly explored. T cells with suppressive ability have been described in several systems, and their biology has been subject of intensive investigation. Although recent advances of T cells controlling immune responses via cell-cell interactions and/or the production of cytokines is currently well described, many aspects of the mechanisms through which suppressor cells exert their effects are currently being elucidated [43]-[45].

Type-1 T Regulatory cells
Type-1 Regulatory (Tr1) cells, also known as inducible Treg are defined by their ability to produce high levels of IL-10 and transforming growth factor-b (TGF-b) [43]-[46]. Antigen-specific Tr1 cells arise in vivo, but may also differentiate from naïve CD4+ T cells. IL-10 and IFN-a have been described to induce the generation of IL-10-producing Tr1 cells from naïve CD4+ T cells activated through T cell receptor and CD28 [47]. In order to inhibit Th1 or Th2 differentiation by using anti-IL-12 and anti-IL-4 Abs, together with a combination of dexamethasone and the active form of vitamin D3, were shown to induce human and naïve CD4+ T cells to differentiate into large numbers of IL-10-producing Tr1 cells in vitro48. In addition, immature DCs and DCs treated with IL-10 or IFN-a were shown to induce naïve CD4+ T cells to differentiate into IL-10-producing Tr1 cells [47]-[49]-[50]. Activation of inducible costimulator (ICOS) on CD4+ T cells by ICOS ligand (ICOSL) enhances differentiation into IL-10-producing Tr1 cells [51]-[53]. During the early course of allergen-specific immunotheraphy (SIT), IL-10- and/or TGF-b-producing Tr1 cells in humans are propagated in vivo, which demonstrates that Tr1 cells are induced by high and increasing dose of allergens [44]-[54]-[55]. IL-10 that is produced and progressively secreted during allergen-SIT appears to counter-regulate synthesis of allergen-specific IgE and IgG4 [46]. IL-10 potently suppresses both total and allergen-spesific IgE, and it stimultaneously increases IgG4 production [56]. In control of Th2 immune response against naturally exposed harmless environmental antigens is mediated by Tr1 cell [57]. In contrast to several Treg related suppressor factors, OX40L has an important role in the negative regulation of the generation and function of IL-10-producing Tr1 cells [58].

CD4+CD25+ Treg Cells
The naturally occurring CD4+ Treg cells, constitute approximately 10% of peripheral CD4+ T cells in normal indivudals and characteristically express CD25 (the interleukin-2 (IL-2) receptor a chain, that is component of the high-affinity IL-2 receptor)59. CD4+ CD25+ Treg cells play major role in maintaining immunological self-tolerance and immune homeostasis. Depletion of this population leads to a variety of autoimmune inflammatory disease such as arthritis and diabetes.

The transcription factor forkhead box p3 (Foxp3) is successfully expressed by CD4+CD25+ Treg cells and essential for functioning regulatory activity. Foxp3 was originally indentified as the gene product affected in lethal X-linked recessive lymphoproliferative disease in mice and human [60]. Mutations in the gene encoding Foxp3 leads lymphoproliferative disease of the scurfy mouse. Male mice with Foxp3 deficiency die about third week of age[61]-[62] Foxp3 deficient mice also experience allergic dysregulation[63]. Adoptive transfer of CD4+CD25+ Treg cells rescues scurfy mice from disease, and Foxp3-transduced CD4+CD25- T cells suppressed wasting and colitis induced by transfer of CD4+CD25- T cells into RAG-deficient mice [61]-[64]. Foxp3 mutations also results homologous autoimmune lymphoproliferative disorder in human subjects, termed immune dysregulation polyendocrinopathy enteropathy-X-linked (IPEX) syndrome and X-linked autoimmunity-allergic disregulation syndrome (XLAAD) [65]-[67]. Males represent with neonatal autoimmune type 1 diabetes with islet cell destruction by infiltrating T cells. Another prominent feature of IPEX/XLAAD is severe allergic inflammation with eczema and food allergy. The IgE levels can be dramatically increased with intense peripheral eosinophilia [66]-[68].

Numerous additional evidence support the role of Foxp3 in Treg cells generation and function. Foxp3-transduced T cells exhibited impaired proliferation and production of cytokines including IL-2 and IL-10 upon TCR stimulation, up-regulated the expression of regulatory T cell-associated molecules such as CD25 and CTLA-4 and suppressed in vitro proliferation of other T cells in a cell-cell contact-dependent manner [60]-[70]. Foxp3 negatively regulates the gene encoding IL-2 and enhances CD25 expression and other Treg cell-associated molecules [60]-[71]-[72] Mice genetically deficient in IL-2, CD25, or CD122 (the IL-2 receptor β chain) and humans with genetic deficiency of CD25 have both reduced numbers and impaired function of Foxp3+ Treg cells. This leads to severe autoimmune inflammatory disease [69]-[73]-[74]. Foxp3 binds to other transcription factors such as NFAT (nuclear factor of activated T cells) and AML1 (acute leukemia-a)/Runx1 (Runt-related transcription factor 1) and potentially interacts with activator protein 1 and nuclear factor kB [75]. The interaction of Foxp3 with NFAT leads the expression of CTLA-4 and CD25 [76]. Recently, thymic production of Foxp3+ Treg cells were analyzed from birth to 10 years of age in humans. The study suggest that from birth to 10 years of age, the thymic production of Foxp3+ Treg cells is stable and correlates with T-lymphopoiesis. However, there is no correlation between thymic and peripheral Foxp3 levels[77]. Taken together Foxp3 is a crucial regulatory gene for the development and function of CD4+CD25+ regulatory T cells, and can be used as marker for Treg cells. Furthermore, Treg cells de novo produced from normal naive T cells by Foxp3 transduction can be instrumental for treatment of autoimmune/inflammatory diseases that require downregulation of hyperactive immune responses.

Downregulated interleukin-7 receptor (CD127) in Treg cells distinguishes Treg cells from activated T cells, facilitating both Treg-cell purification and their functional characterization in human diseases [78]. CD127 has been suggested as a marker, which might distinguish peripheral Foxp3+ Treg cells from activated Foxp3+ nonregulatory T cells[79].

Animal model studies have shown that, naturally occurring CD4+CD25+ Treg cells can control allergic airway disease. Anti-CD25-mediated Treg cell depletion before house dust mite treatment increased several features of the allergic disease (AHR, eosinophilia, and IgE), which was concomitant with elevated Th2 cytokine production[80]. In this study, Treg cell-depleted mice revealed increased numbers of pulmonary MDCs with elevated expression of MHCII, CD80 and CD86. In addition Treg cell-depleted mice have capability to stimulate proliferation of T cells and Th2 type cytokine production with a reduced IL-2 expression. Furthermore, transfer of CD4+CD25+ T regulatory cells to sensitized mice prevents the features of allergic airway disease in vivo [81]. This downregulation of eosinophils, Th2 recruitment, AHR and Th2 cytokine production paralleled with concominant increase in pulmonary IL-10 production. These studies highligth that CD4+CD25+ Treg cells may be used before allergic sensitization to control the development of allergic disease.

In an allergic airway inflammation model with Der p 1 antigen showed that depletion of CD4+CD25+ Foxp3+ Treg cells exacerbates lung eosinophilia, increased draining mediastinal lymph node IL-5 and IL-13, but not IL-10 secretion[82]. Transfer of CD4+ CD25+ Foxp3+ Treg cells from naïve mice reverses allergic inflammation with decreasing IL-5 and IL-13 secretion. In parallel experiment increased IL-10 secretion from regional lymph nodes was observered. In a recent study form our group, we showed that in-vivo CD25 neutralization do not decrease OVA-specific IgE in intranasal OVA immunotheraphy group. (Fig.2, Unpublished data)

One of the mechanisms to induce mucosal tolerance is to increase antigen-spesific Treg cells. Using birch pollen allergen intranasally (Bet v 1) before (prophylaxis) or after sensitization (treatment) resulted in increased Foxp3 mRNA expression in CD4+T cells with IL-10 and TGF-β secretion. A prolonged effect was observed 1 year after immunotheraphy. Long-term efficacy of specific tolerance seems to be associated with the presence of Foxp3+ T cells [83].

It was previously reported that high levels of the soluble form of the IL-6R (sIL-6R) stimulates CD4+CD25+ Treg cell suppressive function in the airways of asthmatic subjects [84]. Blockade of IL-6 in vivo induced local expansion of CD4+CD25+Foxp3+ lung Treg cells with increased immunosuppressive capacities [85]. Again, blockade of IL-6 led to a significant decrease in inflammatory cells by an apoptosis-independent mechanism. In another study, local treatment with anti-IL-6R antibodies that also block signaling via the membrane-bound IL-6R (mIL-6R), which led to decreased signal transducers and activators of transcription (STAT)-3 but not STAT-1 phosphorylation in the lung of treated mice. Moreover this treatment induces apoptosis of the cells present in the airways of OVA-treated mice as well as apoptosis of lung CD4+ effector T cells. Blockade of mIL-6R signaling leads to cell death of lung effector T cells by activating Treg cells in experimental model of asthma[86]. These recent data suggest that local targeting of IL-6R signaling upregulates Th2 cell death in allergic airways via Treg cells.

Sublingual administration of two different tricylated pseudodipeptidic molecules modulate Th1/Treg polarization. While both OM-197-MP-AC and OM-294-BA-MP polarize naïve T cells toward the Th1 type with IFN-g production, only OM- 294-BA-MP induces IL-10 gene expression on CD4+ naïve T cells [87]. In this study, sublingual administration of OM-294- BA-MP with antigen enhances tolerans in OVA sensitized BALB/c with preventing both airways hyperresponsiveness and lung inflammation. In another study, adjuvants stimulating IL-10 gene expression by human or murine immune cells are tested sublingually in BALB/c mice sensitized to OVA. A combination of 1,25-dihydroxyvitamin D3 plus dexamethasone (VitD3/Dex) as well as Lactobacillus plantarum induce IL-10 production by human and murine DCs. Following stimulation with VitD3/Dex-pretreated DCs, CD4+ naïve T cells exhibit a Foxp3+Treg cells[88].


Animal models of allergic disease such as, AR, AD, food allergy allergic conjunctivitis and allergic asthma are valuable models in laboratory studies. Although those models cannot carry all clinical features itself, they are important in order to understand entire mechanisms of the disease and therapeutic approaches. Especially mouse models are being developed to model asthma exacerbations, and investigators are using acute and chronic allergen challenge in their investigations.

Animal models which are more closely reflect asthma, and use of human system will boarden our knowledge of the disease and help identify and evaluate new therapeutic targets.

This work was founded by Marmara University research project BAPKO No. SAĞ-A-070808-0204


1) Asher MI, Montefort S, Bjorksten B, et al. Worldwide time trends in the prevalence of symptoms of asthma allergic rhinoconjunctivitis, and eczema in childhood: ISAAC Phases One and Three repeat multicountry crosssectional surveys. Lancet, 368:733-43, 2006.

2) Janson C, Anto J, Burney P, et al. The European Community Respiratory Health Survey: what are the main results so far? European Community Respiratory Health Survey II. Eur Respir J, 18:598-611, 2001.

3) Bousquet J, Jeffery PK, Busse WW, Johnson M, Vignola AM. Asthma. From bronchoconstriction to airways inflammation and remodeling. Am J Respir Crit Care Med 161:1720-45, 2000.

4) Akkoc T, Tolunay S, Barlan I, Basaran M. Airway remodeling and serum total immunoglobulin E (IgE) levels in a murine model of asthma. J Asthma 2001;38:585-91.

5) Fish JE, Peters SP. Airway remodeling and persistent airway obstruction in asthma. J Allergy Clin Immunol 104:509-16, 1999.

6) Zosky GR, Sly PD. Animal models of asthma. Clin Exp Allergy 2007;37:973-88.

7) Nials AT, Uddin S. Mouse models of allergic asthma: acute and chronic allergen challenge. Dis Model Mech 1:213-20, 2008.

8) Wagner JG, Harkema JR. Rodent models of allergic rhinitis: relevance to human pathophysiology. Curr Allergy Asthma Rep 7:134-40, 2007.

9) Dearman RJ, Kimber I. A mouse model for food allergy using intraperitoneal sensitization. Methods 41:91-8 2007.

10) Jin H, He R, Oyoshi M, Geha RS. Animal models of atopic dermatitis. J Invest Dermatol 129:31-40, 2009.

11) Niederkorn JY. Immune regulatory mechanisms in allergic conjunctivitis: insights from mouse models. Curr Opin Allergy Clin Immunol 8:472-6, 2008.

12) Karol MH. Animal models of occupational asthma. Eur Respir J 7:555-68, 1994.

13) Bice DE, Seagrave J, Green FH. Animal models of asthma: potential usefulness for studying health effects of inhaled particles. Inhal Toxicol 12:829-62, 2000.

14) Akdis M, Akdis CA. Therapeutic manipulation of immune tolerance in allergic disease. Nat Rev Drug Discov 8:645-60, 2009.

15) Romagnani S. Lymphokine production by human T cells in disease states. Annu Rev Immunol 12:227-57, 1994.

16) Mosmann TR, Sad S. The expanding universe of T-cell subsets: Th1, Th2 and more. Immunol Today 17:138-46 1996.

17) Corry DB. IL-13 in allergy: home at last. Curr Opin Immunol 11:610-4, 1999.

18) Schneider T, van Velzen D, Moqbel R, Issekutz AC. Kinetics and quantitation of eosinophil and neutrophil recruitment to allergic lung inflammation in a brown Norway rat model. Am J Respir Cell Mol Biol 17:702-12 1997.

19) Bautsch W, Hoymann HG, Zhang Q, et al. Cutting edge: guinea pigs with a natural C3a-receptor defect exhibit decreased bronchoconstriction in allergic airway disease: evidence for an involvement of the C3a anaphylatoxin in the pathogenesis of asthma. J Immunol 165:5401-5, 2000.

20) Shin YS, Takeda K, Gelfand EW. Understanding asthma using animal models. Allergy Asthma Immunol Res 1:10-8, 2009.

21) Noelpp B, Noelpp-Eschenhagen I. [Experimental bronchial asthma in the guinea pig. IV. Experimental asthma in the guinea pig as an experimental model.]. Int Arch Allergy Appl Immunol 3:207-17, 1952.

22) Ricciardolo FL, Nijkamp F, De Rose V, Folkerts G. The guinea pig as an animal model for asthma. Curr Drug Targets 9:452-65, 2008.

23) Watanabe A, Hayashi H. Allergen-induced biphasic bronchoconstriction in rats. Int Arch Allergy Appl Immunol 93:26-34, 1990.

24) Bellofiore S, Martin JG. Antigen challenge of sensitized rats increases airway responsiveness to methacholine. J Appl Physiol 65:1642-6, 1988.

25) Ewart SL, Kuperman D, Schadt E, et al. Quantitative trait loci controlling allergen-induced airway hyperresponsiveness in inbred mice. Am J Respir Cell Mol Biol 23:537-45, 2000.

26) McIntire JJ, Umetsu SE, Akbari O, et al. Identification of Tapr (an airway hyperreactivity regulatory locus) and the linked Tim gene family. Nat Immunol 2:1109-16 2001.

27) Herz U, Renz H, Wiedermann U. Animal models of type I allergy using recombinant allergens. Methods 32:271- 80, 2004.

28) Kumar RK, Herbert C, Foster PS. The “classical” ovalbumin challenge model of asthma in mice. Curr Drug Targets 9:485-94, 2008.

29) Fuchs B, Braun A. Improved mouse models of allergy and allergic asthma - chances beyond ovalbumin. Curr Drug Targets 9:495-502, 2008

30) Conrad ML, Yildirim AO, Sonar SS, et al. Comparison of adjuvant and adjuvant-free murine experimental asthma models. Clin Exp Allergy 39:1246-54, 2009.

31) Johnson JR, Wiley RE, Fattouh R, et al. Continuous exposure to house dust mite elicits chronic airway inflammation and structural remodeling. Am J Respir Crit Care Med 169:378-85, 2004.

32) Sarpong SB, Zhang LY, Kleeberger SR. A novel mouse model of experimental asthma. Int Arch Allergy Immunol 132:346-54, 2003.

33) Blyth DI, Pedrick MS, Savage TJ, Hessel EM, Fattah D. Lung inflammation and epithelial changes in a murine model of atopic asthma. Am J Respir Cell Mol Biol 14:425-38, 1996.

34) Barrett EG, Rudolph K, Bowen LE, Muggenburg BA Bice DE. Effect of inhaled ultrafine carbon particles on the allergic airway response in ragweed-sensitized dogs. Inhal Toxicol 15:151-65, 2003.

35) Kurup VP, Choi H, Murali PS, Resnick A, Fink JN, Coffman RL. Role of particulate antigens of Aspergillus in murine eosinophilia. Int Arch Allergy Immunol 112:270- 8, 1997.

36) Chapoval SP, Iijima K, Marietta EV, et al. Allergic inflammatory response to short ragweed allergenic extract in HLA-DQ transgenic mice lacking CD4 gene. J Immunol 168:890-9, 2002.

37) Takeda K, Gelfand EW. Mouse models of allergic diseases. Curr Opin Immunol 21:660-5, 2009.

38) Fernandez-Rodriguez S, Ford WR, Broadley KJ, Kidd EJ. Establishing the phenotype in novel acute and chronic murine models of allergic asthma. Int Immunopharmacol 8:756-63 2008.

39) Temelkovski J, Hogan SP, Shepherd DP, Foster PS Kumar RK. An improved murine model of asthma: selective airway inflammation, epithelial lesions and increased methacholine responsiveness following chronic exposure to aerosolised allergen. Thorax 53:849-56, 1998.

40) Wegmann M. Animal models of chronic experimental asthma - strategies for the identification of new therapeutic targets. J Occup Med Toxicol 2008;3 Suppl 1:S4.

41) Kim CH, Ahn JH, Kim SJ, et al. Co-administration of vaccination with DNA encoding T cell epitope on the Der p and BCG inhibited airway remodeling in a murine model of chronic asthma. J Asthma 43:345-53, 2006.

42) Gershon RK, Kondo K. Cell interactions in the induction of tolerance: the role of thymic lymphocytes. Immunology 18:723-37, 1970.

43) Groux H, O’Garra A, Bigler M, et al. A CD4+ T-cell subset inhibits antigen-specific T-cell responses and prevents colitis. Nature 389:737-42, 1997.

44) Akdis CA, Blesken T, Akdis M, Wuthrich B, Blaser K. Role of interleukin 10 in specific immunotherapy. J Clin Invest 102:98-106, 1998.

45) Akdis CA, Blaser K. IL-10-induced anergy in peripheral T cell and reactivation by microenvironmental cytokines: two key steps in specific immunotherapy. Faseb J 13:603- 9, 1999.

46) Akdis M, Akdis CA. Mechanisms of allergen-specific immunotherapy. J Allergy Clin Immunol 119:780-91, 2007.

47) Levings MK, Gregori S, Tresoldi E, Cazzaniga S, Bonini C, Roncarolo MG. Differentiation of Tr1 cells by immature dendritic cells requires IL-10 but not CD25+CD4+ Tr cells. Blood 105:1162-9, 2005.

48) Barrat FJ, Cua DJ, Boonstra A, et al. In vitro generation of interleukin 10-producing regulatory CD4(+) T cells is induced by immunosuppressive drugs and inhibited by T helper type 1 (Th1)- and Th2-inducing cytokines. J Exp Med 195:603-16, 2002.

49) De Smedt T, Van Mechelen M, De Becker G, Urbain J Leo O, Moser M. Effect of interleukin-10 on dendritic cell maturation and function. Eur J Immunol 27:1229-35 1997.

50) Jonuleit H, Schmitt E, Schuler G, Knop J, Enk AH. Induction of interleukin 10-producing, nonproliferating CD4(+) T cells with regulatory properties by repetitive stimulation with allogeneic immature human dendritic cells. J Exp Med 192:1213-22, 2000.

51) Akbari O, Freeman GJ, Meyer EH, et al. Antigen-specific regulatory T cells develop via the ICOS-ICOS-ligand pathway and inhibit allergen-induced airway hyperreactivity. Nat Med 8:1024-32, 2002.

52) Beier KC, Hutloff A, Dittrich AM, et al. Induction, binding specificity and function of human ICOS. Eur J Immunol 30:3707-17, 2000.

53) Witsch EJ, Peiser M, Hutloff A, et al. ICOS and CD28 reversely regulate IL-10 on re-activation of human effector T cells with mature dendritic cells. Eur J Immunol 32:2680-6 2002.

54) Jutel M, Akdis M, Budak F, et al. IL-10 and TGF-beta cooperate in the regulatory T cell response to mucosal allergens in normal immunity and specific immunotherapy. Eur J Immunol 33:1205-14, 2003.

55) Nasser SM, Ying S, Meng Q, Kay AB, Ewan PW. Interleukin- 10 levels increase in cutaneous biopsies of patients undergoing wasp venom immunotherapy. Eur J Immunol 31:3704-13, 2001.

56) Punnonen J, de Waal Malefyt R, van Vlasselaer P, Gauchat JF, de Vries JE. IL-10 and viral IL-10 prevent IL-4-induced IgE synthesis by inhibiting the accessory cell function of monocytes. J Immunol 151:1280-9, 1993.

57) Akdis M, Verhagen J, Taylor A, et al. Immune responses in healthy and allergic individuals are characterized by a fine balance between allergen-specific T regulatory 1 and T helper 2 cells. J Exp Med 199:1567-75, 2004.

58) Ito T, Wang YH, Duramad O, et al. OX40 ligand shuts down IL-10-producing regulatory T cells. Proc Natl Acad Sci U S A 103:13138-43, 2006.

59) Sakaguchi S. Regulatory T cells: key controllers of immunologic self-tolerance. Cell 101:455-8, 2000.

60) Godfrey VL, Wilkinson JE, Russell LB. X-linked lymphoreticular disease in the scurfy (sf) mutant mouse. Am J Pathol 138:1379-87, 1991.

61) Fontenot JD, Gavin MA, Rudensky AY. Foxp3 programs the development and function of CD4+CD25+ regulatory T cells. Nat Immunol 4:330-6, 2003.

62) Lyon MF, Peters J, Glenister PH, Ball S, Wright E. The scurfy mouse mutant has previously unrecognized hematological abnormalities and resembles Wiskott-Aldrich syndrome. Proc Natl Acad Sci U S A 87:2433-7, 1990.

63) Lin W, Truong N, Grossman WJ, et al. Allergic dysregulation and hyperimmunoglobulinemia E in Foxp3 mutant mice. J Allergy Clin Immunol 116:1106-15, 2005.

64) Khattri R, Cox T, Yasayko SA, Ramsdell F. An essential role for Scurfin in CD4+CD25+ T regulatory cells. Nat Immuno l 4:337-42, 2003.

65) Bennett CL, Christie J, Ramsdell F, et al. The immune dysregulation polyendocrinopathy, enteropathy, X-linked syndrome (IPEX) is caused by mutations of FOXP3. Nat Genet 27:20-1, 2001.

66) Chatila TA, Blaeser F, Ho N, et al. JM2, encoding a fork head-related protein, is mutated in X-linked autoimmunity- allergic disregulation syndrome. J Clin Invest 106:R75- 81, 2000.

67) Wildin RS, Smyk-Pearson S, Filipovich AH. Clinical and molecular features of the immunodysregulation, polyendocrinopathy enteropathy, X linked (IPEX) syndrome. J Med Genet 39:537-45, 2002.

68) Nieves DS, Phipps RP, Pollock SJ, et al. Dermatologic and immunologic findings in the immune dysregulation polyendocrinopathy, enteropathy, X-linked syndrome. Arch Dermatol 140:466-72, 2004.

69) Hori S, Nomura T, Sakaguchi S. Control of regulatory T cell development by the transcription factor Foxp3. Science 299:1057-61, 2003.

70) Yagi H, Nomura T, Nakamura K, et al. Crucial role of FOXP3 in the development and function of human CD25+CD4+ regulatory T cells. Int Immunol 2004;16:1643-56.

71) Gavin M, Rudensky A. Control of immune homeostasis by naturally arising regulatory CD4+ T cells. Curr Opin Immunol 15:690-6, 2003.

72) Sakaguchi S, Powrie F. Emerging challenges in regulatory T cell function and biology. Science 317:627-9, 2007.

73) Fontenot JD, Rasmussen JP, Gavin MA, Rudensky AY. A function for interleukin 2 in Foxp3-expressing regulatory T cells. Nat Immunol 6:1142-51, 2005.

74) Sakaguchi S. Naturally arising Foxp3-expressing CD25+CD4+ regulatory T cells in immunological tolerance to self and non-self. Nat Immunol 6:345-52, 2005.

75) Ziegler SF. FOXP3: of mice and men. Annu Rev Immunol 24:209-26, 2006.

76) Wu Y, Borde M, Heissmeyer V, et al. FOXP3 controls regulatory T cell function through cooperation with NFAT. Cell 126:375-87, 2006.

77) Tuovinen H, Laurinolli TT, Rossi LH, Pekkarinen PT Mattila I, Arstila TP. Thymic production of human FOXP3(+) regulatory T cells is stable but does not correlate with peripheral FOXP3 expression. Immunol Lett 2008.

78) Tiemessen MM, Jagger AL, Evans HG, van Herwijnen MJ, John S, Taams LS. CD4+CD25+Foxp3+ regulatory T cells induce alternative activation of human monocytes/ macrophages. Proc Natl Acad Sci U S A 104:19446-51 2007.

79) Di Ianni M, Del Papa B, De Ioanni M, et al. Mesenchymal cells recruit and regulate T regulatory cells. Exp Hematol 36:309-18, 2008.

80) Lewkowich IP, Herman NS, Schleifer KW, et al. CD4+CD25+ T cells protect against experimentally induced asthma and alter pulmonary dendritic cell phenotype and function. J Exp Med 202:1549-61, 2005.

81) Kearley J, Barker JE, Robinson DS, Lloyd CM. Resolution of airway inflammation and hyperreactivity after in vivo transfer of CD4+CD25+ regulatory T cells is interleukin 10 dependent. J Exp Med 202:1539-47, 2005.

82) Leech MD, Benson RA, De Vries A, Fitch PM, Howie SE. Resolution of Der p1-induced allergic airway inflammation is dependent on CD4+CD25+Foxp3+ regulatory cells. J Immunol 179:7050-8, 2007.

83) Winkler B, Hufnagl K, Spittler A, et al. The role of Foxp3+ T cells in long-term efficacy of prophylactic and therapeutic mucosal tolerance induction in mice. Allergy 61:173-80, 2006.

84) Doganci A, Sauer K, Karwot R, Finotto S. Pathological role of IL-6 in the experimental allergic bronchial asthma in mice. Clin Rev Allergy Immunol 28:257-70, 2005.

85) Doganci A, Eigenbrod T, Krug N, et al. The IL-6R alpha chain controls lung CD4+CD25+ Treg development and function during allergic airway inflammation in vivo. J Clin Invest 115:313-25, 2005.

86) Finotto S, Eigenbrod T, Karwot R, et al. Local blockade of IL-6R signaling induces lung CD4+ T cell apoptosis in a murine model of asthma via regulatory T cells. Int Immunol 19:685-93, 2007.

87) Mascarell L, Van Overtvelt L, Lombardi V, et al. A synthetic triacylated pseudo-dipeptide molecule promotes Th1/TReg immune responses and enhances tolerance induction via the sublingual route. Vaccine 26:108-18 2007.

88) Van Overtvelt L, Lombardi V, Razafindratsita A, et al. IL-10-inducing adjuvants enhance sublingual immunotherapy efficacy in a murine asthma model. Int Arch Allergy Immunol 145:152-62, 2008.

Marmara University