Intranasal Ovalbumin Challenge Research Articles

Effects of Thymus quinquecostatus Celakovski on Allergic Responses in OVA-Induced Allergic Rhinitis Mice

Allergic rhinitis (AR) is defined allergic disease that is mediated by Th2 cells. Its incidence rate is showing a growing tendency worldwide. Research on traditional medicine for AR is also being increasingly conducted. Thymus quinquecostatus Celakovski (TQ) has been used as an important medicinal and aromatic plant in the world. The purpose of this study was to assess whether TQ can alleviate AR. BALB/c mice were sensitized and challenged with ovalbumin (OVA) to provoke AR. Mice were treated with ethanol extract of TQ at 10 or 100 mg/kg after the intranasal OVA challenge. Their clinical symptoms such as nasal rubbing and sneezing were significantly reduced in the ethanol extract group (10 or 100 mg/kg) compared to the OVA group. Serum levels of Th1 (TNF-α) and Th2 (IL-4, IL-5, and IL-6) cytokines and IgE levels (both total and OVA-specific) were significantly reduced by administration of ethanol extract of TQ at 100 mg/kg. The thicknesses of the nasal septum and epithelium were significantly reduced by the administration of ethanol extract of TQ. These results suggest that TQ may inhibit early and late phases of AR reactions.

Triple-tyrosine kinase inhibition by BIBF1000 attenuates airway and pulmonary arterial remodeling following chronic allergen challenges in mice

BackgroundAirway remodeling is an important pathological feature of chronic airway diseases, which leads to a progressive decline in lung function. The present study examined the anti-remodeling and anti- inflammatory effect of BIBF1000, a triple-tyrosine kinase inhibitor that targets VEGF, PDGF, and FGF receptor signaling in a mouse model of repeated ovalbumin (OVA) challenges.MethodsFemale Balb-c mice were immunized intraperitoneally on days 0 and 12 with 50 µg ovalbumin plus 1 mg of Al(OH)3 in 200 μl saline. Intranasal OVA challenges (20 µg/50 µl in PBS) were administered on days 26, 29, and 31, and were repeated twice a week for 3 months. Animals received vehicle or BIBF1000 (25 mg/kg, b.i.d.) through gavage from day 26 to the end of fourth month. On day 120, bronchoalveolar lavage (BAL) and lung tissue were collected for biochemical and immunohistological analysis.ResultsCompared to vehicle controls, treatment with BIBF1000 reduced the numbers of BAL eosinophils, macrophages, neutrophils, and lymphocytes by 70.0%, 57.9%, 47.5%, and 63.0%, respectively, and reduced IL-5 and IL-13 in BAL. Treatment with BIBF1000 reduced airway mucus secretion, peribronchial fibrosis, small airway, and pulmonary arterial wall thickness, compared to vehicle controls. Furthermore, treatment with BIBF1000 also reduced the expression of inflammatory mediators (TNF-α, IL-1β, IL-5, IL-13, MMP-2, MMP-9, COX-2, and iNOS) and inhibited ERK and AKT phosphorylation.ConclusionsThe protective effect afforded by triple-tyrosine kinase inhibition with BIBF1000 in reducing allergen-induced airway and arterial remodeling was associated with down-regulation of inflammatory mediators, as well as inhibition of ERK and AKT signaling pathways.

Synergistic effect of roflumilast with dexamethasone in a neutrophilic asthma mouse model.

Asthma is a chronic airway inflammatory disease with heterogeneous features. Most cases of asthma are steroid sensitive, but 5%-10% are unresponsive to steroids, leading to challenges in treatment. Neutrophilic asthma is steroid-resistant and characterized by the absence or suppression of the T-helper type II (TH 2) process and an increase in the TH 1 and/or TH 17 process. Roflumilast (ROF) has anti-inflammatory effects and has been used to treat chronic inflammatory airway diseases, such as chronic pulmonary obstructive disease. It is unclear whether ROF may have a therapeutic role in neutrophilic asthma. In this study, we investigated the synergistic effect of ROF with dexamethasone (DEX) in a neutrophilic asthma mouse model. C57BL/6 female mice sensitized to ovalbumin (OVA) were exposed to five intranasal OVA treatments and three intranasal lipopolysaccharide (LPS) treatments for an additional 10days. During the intranasal OVA challenge, ROF was administrated orally, and DEX was injected intraperitoneally. Protein, pro-inflammatory cytokines, inflammatory cytokines and other suspected markers were identified by enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and western blot. Following exposure to LPS in OVA-induced asthmatic mice, neutrophil predominant airway inflammation rather than eosinophil predominant inflammation was observed, with increases in airway hyperresponsiveness (AHR). The lungs of animals treated with ROF exhibited less airway inflammation and hyperresponsiveness. To investigate the mechanism underlying this effect, we examined the expression of proinflammatory cytokines suspected to be involved in inflammatory cytokines and proteins. Roflumilast reduced total protein in bronchioalveolar lavage fluid; levels of interleukin (IL)-17A, IL-1β messenger RNA, interferon γ and tumour necrosis factor α; and recovered histone deacetylase-2 (HDAC2) activity. Combination therapy with ROF and DEX further reduced the levels of IL-17, IL-22 and IL-1β mRNA and proinflammatory cytokines. The combination of ROF and DEX reduced lung inflammation and AHR much more than one of them alone. Roflumilast reduces AHR and lung inflammation in the neutrophilic asthma mouse model. Furthermore, additive effects were observed when DEX was added to ROF treatment, possibly because of recovery of HDAC2/β-actin activity. This study demonstrates the anti-inflammatory properties of ROF in a neutrophilic asthma mouse model.

Novel pendrin inhibitor attenuates airway hyperresponsiveness and mucin expression in experimental murine asthma

Novel pendrin inhibitor attenuates airway hyperresponsiveness and mucin expression in experimental murine asthma

IL-22 promotes allergic airway inflammation in epicutaneously sensitized mice

Serum IL-22 levels are increased in patients with atopic dermatitis, which commonly precedes asthma in the atopic march. Epicutaneous sensitization in mice results in TH2-dominated skin inflammation that mimics atopic dermatitis and sensitizes the airways for antigen challenge-induced allergic inflammation characterized by the presence of both eosinophils and neutrophils. Epicutaneous sensitization results in increased serum levels of IL-22. We sought to determine the role of IL-22 in antigen-driven airway allergic inflammation after inhalation challenge in epicutaneously sensitized mice. Wild-type (WT) and Il22-/- mice were sensitized epicutaneously or immunized intraperitoneally with ovalbumin (OVA) and challenged intranasally with antigen. OVA T-cell receptor-specific T cells were TH22 polarized invitro. Airway inflammation, mRNA levels in the lungs, and airway hyperresponsiveness (AHR) were examined. Epicutaneous sensitization preferentially elicited an IL-22 response compared with intraperitoneal immunization. Intranasal challenge of mice epicutaneously sensitized with OVA elicited in the lungs Il22 mRNA expression, IL-22 production, and accumulation of CD3+CD4+IL-22+ T cells that coexpressed IL-17A and TNF-α. Epicutaneously sensitized Il22-/- mice exhibited diminished eosinophil and neutrophil airway infiltration and decreased AHR after intranasal OVA challenge. Production of IL-13, IL-17A, and TNF-α was normal, but IFN-γ production was increased in lung cells from airway-challenged and epicutaneously sensitized Il22-/- mice. Intranasal instillation of IFN-γ-neutralizing antibody partially reversed the defect in eosinophil recruitment. WT recipients of TH22-polarized WT, but not IL-22-deficient, T-cell receptor OVA-specific T cells, which secrete both IL-17A and TNF-α, had neutrophil-dominated airway inflammation and AHR on intranasal OVA challenge. Intranasal instillation of IL-22 with TNF-α, but not IL-17A, elicited neutrophil-dominated airway inflammation and AHR in WT mice, suggesting that loss of IL-22 synergy with TNF-α contributed to defective recruitment of neutrophils into the airways of Il22-/- mice. TNF-α, but not IL-22, blockade at the time of antigen inhalation challenge inhibited airway inflammation in epicutaneously sensitized mice. Epicutaneous sensitization promotes generation of antigen-specific IL-22-producing T cells that promote airway inflammation and AHR after antigen challenge, suggesting that IL-22 plays an important role in the atopic march.

Peucedanum japonicum extract attenuates allergic airway inflammation by inhibiting Th2 cell activation and production of pro-inflammatory mediators

Ethnopharmacological relevanceThe root of Peucedanum japonicum Thunberg is traditionally used to treat coughs, colds, headache and inflammatory diseases in Korea and Japan. Its effects on allergic lung inflammation have not been investigated. Aim of the studyTo investigate the anti-asthmatic effects of Peucedanum japonicum extract (PJE) using a murine model of asthma and a lipopolysaccharide (LPS)-stimulated macrophage cell line. Materials and methodsMice underwent two rounds of sensitization with ovalbumin 1 week apart followed by four intranasal ovalbumin challenges on days 13–16. The control group received saline only. Two ovalbumin-sensitized groups were orally administered vehicle or PJE (200mg/kg) 5 days a week starting 1 week before the first ovalbumin sensitization. The third group was orally administered the asthma medication Montelukast (10mg/kg) on days 12–16. All animals were sacrificed on day 17. The lungs were assessed for histological features, inflammatory cell infiltration, Th2 cell activation and GATA-binding protein-3 (GATA-3) expression. The bronchoalveolar lavage fluid (BALF) was assessed for type 2 cytokine levels. The effect of PJE on the in vitro Th2 polarization of naïve CD4+ splenocytes and the production of pro-inflammatory mediators and cytokines by LPS-stimulated RAW 264.7 cells was evaluated. ResultsPJE treatment inhibited OVA-induced inflammatory cell infiltration, eosinophilia, Th2 activation, and GATA-3 expression in the lung, reduced the interleukin (IL)-5 and IL-13 levels in BALF, down-regulated Th2 activation in vitro, and inhibited the macrophage production of inducible nitric oxide, cyclooxygenase-2, tumor necrosis factor-α, and IL-6. ConclusionPJE attenuated allergic airway inflammation by inhibiting Th2 cell activation and macrophage production of inflammatory mediators. Peucedanum japonicum may be candidate therapy for allergic lung inflammation.

Treatment of allergic rhinitis with CpG oligodeoxynucleotides alleviates the lower airway outcomes of combined allergic rhinitis and asthma syndrome via a mechanism that possibly involves in TSLP

ABSTRACTPurpose: Thymic stromal lymphopoietin (TSLP) is a critical regulator of immune responses associated with Th2 cytokine-mediated inflammation. Intranasal administration of oligodeoxynucleotides with CpG motifs (CpG-ODNs) might improve lower airway outcomes of combined allergic rhinitis and asthma syndrome (CARAS), but the inherent mechanisms of CpG-ODNs are not well defined. This study investigated whether CpG-ODNs treated to upper airway could reduce lower airway TSLP expression as well as whether this reduction could contribute to the alleviation of lower allergic inflammation and airway hyper-reactivity (AHR) in CARAS mice. Materials and Methods: Ovalbumin (OVA)-sensitized BALB/c mice were intranasal OVA exposure three times a week for 3 weeks. CpG-ODNs or an anti-TSLP mAb was administered to a subset of these mice 1 hour after intranasal OVA challenge, followed by 5 days of OVA aerosol challenge. The resulting immunological variables, nasal symptoms, and nasal mucosa and lung tissues pathology were evaluated. TSLP production in the lung tissues and bronchoalveolar lavage fluid (BALF) were determined by RT-PCR, western blotting or enzyme-linked immunosorbent assay. Results: The CARAS mice exhibited overexpression of TSLP in the lung tissues and BALF, and also demonstrated significant increases in BALF and splenocyte Th2-associated cytokine production, serum OVA-specific IgE, nose and lung pathologies, and AHR. Intranasal administration of CpG-ODNs restored TSLP in the lower airway, and it significantly reduced the following parameters: Th2-type cytokine production levels; the percentage of eosinophils in the BALF; IL-4 and IL-5 concentrations in the supernatants of cultured splenic lymphocytes; serum OVA-specific IgE; peribronchial inflammation score in the lungs; and nose pathology and nasal symptoms. Similar results were obtained when the CARAS mice were treated with an anti-TSLP mAb to block intranasal TSLP activity. Conclusions: Treatment with intranasal CpG-ODNs improves lower airway immunological variable outcomes in the CARAS model via a mechanism that possibly involves in suppressing pulmonary TSLP-triggered allergic inflammation.

Effect of roflumilast on airway remodelling in a murine model of chronic asthma.

Airway remodelling is associated with irreversible, or partially reversible, airflow obstruction and ultimately unresponsiveness to asthma therapies such as corticosteroids. Roflumilast is a selective phosphodiesterase-4 inhibitor that has an anti-inflammatory effect in chronic obstructive pulmonary disease (COPD). The objective of this study was to study the effect of roflumilast on airway inflammation and remodelling in a murine model of chronic asthma. BALB/c mice sensitized to ovalbumin (OVA) were chronically exposed to intranasal OVA administration twice a week for additional 3months. Roflumilast was administered orally during the intranasal OVA challenge. A lung fibroblast cell line was used in the proliferation assay. Compared with control mice, mice chronically exposed to OVA developed eosinophilic airway inflammation, airway hyper-responsiveness (AHR), and exhibited features of airway remodelling. Administration of roflumilast significantly inhibited airway inflammation and AHR. Roflumilast also significantly decreased goblet cell hyperplasia and pulmonary fibrosis, which are parameters of airway remodelling. The levels of interleukin (IL)-4, IL-5, and IL-13 in the bronchoalveolar lavage (BAL) fluids were significantly lower in the roflumilast group. In vitro, roflumilast significantly inhibited stem cell factor (SCF)-induced cell proliferation of fibroblasts. The SCF concentration and mRNA expression in a murine model also significantly decreased with roflumilast treatment. These results suggest that the administration of roflumilast regulates airway inflammation, AHR, and airway remodelling in a model of chronic asthma. The beneficial effects from roflumilast may be related to the SCF/c-kit pathway.

Allergic skin sensitization promotes eosinophilic esophagitis through the IL-33–basophil axis in mice

Eosinophilic esophagitis (EoE) is an allergic inflammatory disorder characterized by accumulation of eosinophils in the esophagus. EoE often coexists with atopic dermatitis, a chronic inflammatory skin disease. The impaired skin barrier in patients with atopic dermatitis has been suggested as an entry point for allergic sensitization that triggers development of EoE. We sought to define the mechanisms whereby epicutaneous sensitization through a disrupted skin barrier induces development of EoE. To elicit experimental EoE, mice were epicutaneously sensitized with ovalbumin (OVA), followed by intranasal OVA challenge. Levels of esophageal mRNA for TH2 cytokines and the IL-33 receptor Il1rl1 (St2) were measured by using quantitative PCR. Esophageal eosinophil accumulation was assessed by using flow cytometry and hematoxylin and eosin staining. Invivo basophil depletion was achieved with diphtheria toxin treatment of Mcpt8DTR mice, and animals were repopulated with bone marrow basophils. mRNA analysis of esophageal biopsy specimens from patients with EoE was used to validate our findings in human subjects. Epicutaneous sensitization and intranasal challenge of wild-type mice resulted in accumulation of eosinophils and upregulation of TH2 cytokines and St2 in the esophagus. Disruption of the IL-33-ST2 axis or depletion of basophils reduced these features. Expression of ST2 on basophils was required to accumulate in the esophagus and transfer experimental EoE. Expression of IL1RL1/ST2 mRNA was increased in esophageal biopsy specimens from patients with EoE. Topical OVA application on unstripped skin induced experimental EoE in filaggrin-deficient flaky tail (ft/ft) mice but not in wild-type control or ft/ft.St2-/- mice. Epicutaneous allergic sensitization promotes EoE, and this is critically mediated through the IL-33-ST2-basophil axis.

Dexamethasone suppresses allergic rhinitis and amplifies CD4(+) Foxp3(+) regulatory T cells in vitro.

Glucocorticosteroids (GCs) are highly effective in mitigating allergic inflammation. In this study, we investigate the effects of dexamethasone (DEX) on regulatory T cells (Tregs) in a murine model of allergic rhinitis (AR). BALB/c mice were sensitized to ovalbumin (OVA) followed by intranasal OVA challenge. Mice in the treatment group received DEX by intraperitoneal injection (5 mg/kg/day) 1 hour before the OVA challenge. Further, CD4(+) CD25(-) T cells from the spleens were cultured in presence of DEX. The effects of DEX on CD4(+) Foxp3(+) T cells were then assessed in vivo as well as in vitro. Frequencies of sneezing and scratching decreased significantly in the DEX-treated group compared to that in the OVA group. Histopathological analyses showed that DEX restored the destroyed and discontinuous ciliated epithelium of the nasal mucosa in the OVA group. Moreover, DEX inhibited the production of interleukin (IL)-4, IL-5, and IL-13 in the nasal cavity lavage fluid in this group. We also observed a significant increase in the percentage of CD4(+) Foxp3(+) T cells in the OVA group. In vivo, DEX treatment significantly decreased the number of CD4(+) Foxp3(+) T cells. However, in vitro, the proportion of these cells increased in the presence of DEX. Furthermore, the number of late stage apoptotic CD4(+) T cells was also significantly increased upon exposure to DEX. DEX therapy effectively suppresses AR symptoms, but does not result in the expected increase in the frequency of Tregs in vivo. Thus, whether GCs exert immunosuppressive effects by influencing the number of Tregs remains unresolved.

Thymic stromal lymphopoietin signaling in CD4+ T cells is required for TH2 memory

Thymic stromal lymphopoietin (TSLP) is a key factor in the development of allergic asthma. Numbers of TH2 memory cells gradually increase in allergic patients with the progression of disease and persist in the lungs during remission, although the mechanism is not clear. We sought to define the role of TSLP in TH2 memory cell generation and maintenance in vivo. Adoptive transfer of wild-type and thymic stromal lymphopoietin receptor (TSLPR)-deficient ovalbumin-specific CD4(+) T cells before TH2 sensitization was used to define T cell-specific TSLP effects. Atopic dermatitis and increased serum TSLP concentrations were induced by topical application of the vitamin D3 analog MC903. Memory cells in peripheral blood were monitored weekly with flow cytometry. Memory recall was tested after intranasal ovalbumin challenge. TSLP signaling in CD4(+) T cells is required for the generation/maintenance of memory cells after in vivo priming. TSLPR-deficient CD4(+) T cells have no defects in proliferation but do not survive 1 week after sensitization, and increased TSLP expression during sensitization significantly increased the frequency of memory cells. Although in vitro-differentiated TSLPR-deficient TH2 cells develop into memory cells with equal efficiency to wild-type cells, the recall response to airway antigen challenge is impaired. Moreover, after antigen challenge of mice with established TH2 memory, TSLP signaling in CD4(+) T cells significantly affects memory cell generation/maintenance from secondary effector cells. TSLP signaling in CD4(+) T cells is required for not only TH2 memory cell formation in vivo but also the recall response of the memory cells to local antigen challenge.

Lactoferrin Administration into the Nostril Alleviates Murine Allergic Rhinitis and its Mechanisms

Lactoferrin (LF) can downregulate allergic airway inflammation in asthma. However, the in vivo effect of exogenous LF on allergic rhinitis (AR), a disease attributed to airway inflammation, has yet to be determined. We investigated the effect of intranasal administration recombinant human (rh) LF and its underlying mechanisms on AR in BALB/c mice. Multiple parameters of allergic responses were evaluated to determine the effect of rhLF. We found that the number of eosinophils and goblet cells, as well as mRNA and protein expression of type 2 helper T (Th2), Th17 and regulatory T (Treg) cells in the nasal cavity, was significantly upregulated in AR mice compared with the controls, Conversely, administration of rhLF prior to or after intranasal ovalbumin challenge markedly downregulated these same parameters. Th1-specific mRNA and protein expression in the nasal cavity of the controls was not different from that in AR mice, but expression significantly increased with rhLF treatment. The mRNA and protein expression of endogenous LF in the nasal cavity was significantly downregulated in AR mice compared with the controls. However, after rhLF treatment, endogenous LF mRNA and protein expression was significantly upregulated. Exogenous rhLF inhibited allergic inflammation in AR mice, most likely by promoting the endogenous LF expression and skewing T cells to a Th1, but not a Th2 and Th17 phenotype in the nasal mucosa. Our findings suggest that rhLF treatment may be a novel therapeutic approach for prevention and treatment AR.

A novel human anti‐VCAM‐1 monoclonal antibody ameliorates airway inflammation and remodelling

Asthma is a chronic inflammatory disease induced by Type 2 helper T cells and eosinophils. Vascular cell adhesion molecule-1 (VCAM-1) has been implicated in recruiting eosinophils and lymphocytes to pathological sites in asthma as a regulatory receptor. Accordingly, monoclonal antibody (mAb) against VCAM-1 may attenuate allergic inflammation and pathophysiological features of asthma. We attempted to evaluate whether a recently developed human anti-VCAM-1 mAb can inhibit the pathophysiological features of asthma in a murine asthma model induced by ovalbumin (OVA). Leucocyte adhesion inhibition assay was performed to evaluate the in vitro blocking activity of human anti-VCAM-1 mAb. OVA-sensitized BALB/c mice were treated with human anti-VCAM-1 mAb or isotype control Ab before intranasal OVA challenge. We evaluated airway hyperresponsiveness (AHR) and bronchoalveolar lavage fluid analysis, measured inflammatory cytokines and examined histopathological features. The human anti-VCAM-1 mAb bound to human and mouse VCAM-1 molecules and inhibited adhesion of human leucocytes in vitro. AHR and inflammatory cell counts in bronchoalveolar lavage fluid were reduced in mice treated with human anti-VCAM-1 mAb as compared with a control Ab. The levels of interleukin (IL)-5 and IL-13, as well as transforming growth factor-β, in lung tissue were decreased in treated mice. Human anti-VCAM-1 mAb reduced goblet cell hyperplasia and peribronchial fibrosis. In vivo VCAM-1 expression decreased in the treated group. In conclusion, human anti-VCAM-1 mAb attenuated allergic inflammation and the pathophysiological features of asthma in OVA-induced murine asthma model. The results suggested that human anti-VCAM-1 mAb could potentially be used as an additional anti-asthma therapeutic medicine.

Proposta de um modelo murino de curta duração de resposta pulmonar alérgica aguda sem utilização de adjuvante

To determine whether a short-term protocol using subcutaneous sensitization with ovalbumin, without the use of adjuvants, would induce an eosinophilic response in the lungs of mice similar to that observed in previous, well-established protocols. Adult female BALB/c mice were randomized and divided into groups according to the number of sensitizations with ovalbumin and the number/dosage of intranasal ovalbumin challenges. The short-term protocol (10 days) consisted of one sensitization with ovalbumin and three ovalbumin challenges (100 µg). Total and differential cell counts in BAL fluid, levels of eosinophil peroxidase in lung tissue, and histopathological examination of the lungs were performed 24 h after the last ovalbumin challenge. No significant differences were found among the groups regarding the variables studied. The short-term protocol, as well as the other protocols studied, induced an eosinophilic response similar to that obtained in the positive control. Subcutaneous sensitization with ovalbumin and without the use of adjuvants resulted in a significant allergic response in the lungs of mice, even in the short-term protocol group. Our findings suggest that this short-term protocol can be used as a first-line pre-clinical test for the study of new medications, reducing the costs and observation periods.

Beneficial Effect of Anti-Interleukin-33 on the Murine Model of Allergic Inflammation of the Lower Airway

Objective. Interleukin (IL)-33, which mediates the Th2 allergic pathway, may play a key role in allergic airway inflammation. This study was conducted to evaluate the therapeutic potential of anti-IL-33 antibody for treatment of allergic inflammation of the lower airway in a murine model. Methods. Twenty-four BALB/c mice were used in this study. Saline was used for sensitization and challenge of mice in Group A (control group, n = 6). Mice in Group B (ovalbumin (OVA) group, n = 6) received intraperitoneal (ip) and intranasal OVA challenge. In Group C (control IgG group, n = 6), mice received ip injection with control IgG prior to OVA challenge. Mice in Group D (anti-IL-33 group, n = 6) received an ip injection of anti-IL-33 prior to challenge. Measurements of serum total and OVA-specific IgE and the number of eosinophils, neutrophils, and lymphocytes in bronchoalveolar lavage (BAL) fluid were performed. We performed histopathologic examination to evaluate the degree of eosinophilic infiltration in lung tissue. Airway hyperreactivity was measured according to change of enhanced pause (Penh). Results. A significant decrease in serum total and OVA-specific IgE and the number of eosinophils and neutrophils in BAL fluid was observed in Group D, compared with Group B or Group C (p < .05). In Group D, treatment with anti-IL-33 resulted in a significant decrease in eosinophilic infiltration in lung tissue, compared with Group B and Group C (p < .05). Degree of airway hyperreactivity, measured by Penh, showed a significant decrease in the anti-IL-33 treatment group, compared with the OVA group or the control IgG treatment group (p < .01, at 50 mg/mL of methacholine). Conclusions: Anti-IL-33 has therapeutic potential for treatment of allergic inflammation of the lower airway.

Adoptive Transfer of Induced-Treg Cells Effectively Attenuates Murine Airway Allergic Inflammation

Both nature and induced regulatory T (Treg) lymphocytes are potent regulators of autoimmune and allergic disorders. Defects in endogenous Treg cells have been reported in patients with allergic asthma, suggesting that disrupted Treg cell-mediated immunological regulation may play an important role in airway allergic inflammation. In order to determine whether adoptive transfer of induced Treg cells generated in vitro can be used as an effective therapeutic approach to suppress airway allergic inflammation, exogenously induced Treg cells were infused into ovalbumin-sensitized mice prior to or during intranasal ovalbumin challenge. The results showed that adoptive transfer of induced Treg cells prior to allergen challenge markedly reduced airway hyperresponsiveness, eosinophil recruitment, mucus hyper-production, airway remodeling, and IgE levels. This effect was associated with increase of Treg cells (CD4+FoxP3+) and decrease of dendritic cells in the draining lymph nodes, and with reduction of Th1, Th2, and Th17 cell response as compared to the controls. Moreover, adoptive transfer of induced Treg cells during allergen challenge also effectively attenuate airway inflammation and improve airway function, which are comparable to those by natural Treg cell infusion. Therefore, adoptive transfer of in vitro induced Treg cells may be a promising therapeutic approach to prevent and treat severe asthma.

Synergism of Staphylococcus aureus Colonization and Allergic Reaction in the Nasal Cavity in Mice

Background: The aim of this study is to investigate the reciprocal effect of Staphylococcus aureus colonization and allergic rhinitis in an allergy model of mice. Methods: BALB/c mice with intraperitoneal ovalbumin (OVA) sensitization and/or intranasal S. aureus inoculation were prepared. The following 4 groups were designed: an OVA-sensitized S. aureus-inoculated (AR-SA) group, an OVA-sensitized uninoculated (AR) group, a nonsensitized S. aureus-inoculated (SA) group, and a nonsensitized uninoculated (control) group. After intranasal OVA challenge, nasal lavage fluid, peripheral blood, and nasal mucosa were collected. Polymorphonuclear cells in the nasal lavage fluid were counted, serum OVA-specific IgE and IgG1 were measured by enzyme immunoassays, and IL-4, IL-5, and IFN-γ mRNAs in the nasal mucosa were assessed by quantitative real-time reverse transcription-PCR. The number of S. aureus in the nasal mucosa and lavage fluid was counted. Results: Both eosinophil and neutrophil counts were larger in the AR-SA group than in the other groups. Both IgE and IgG1 levels were higher in the AR and AR-SA groups than in the SA and control groups, and the IgG1 level was higher in the AR-SA group than in the AR group. The expression of IL-4 mRNA was higher in the AR-SA group than in the other groups, and the expression of IL-5 mRNA was higher in the AR-SA group than in the SA group. The AR-SA group showed higher counts of S. aureus in the nasal mucosa than the SA group. Conclusion: These results indicate the mutually potentiating effect of S. aureus colonization and allergic rhinitis.

Anti‐IL‐33 antibody has a therapeutic effect in a murine model of allergic rhinitis

Interleukin (IL)-33 is involved in the Th2 immune response and could play an essential role in nasal allergy. Therefore, we aimed to investigate the therapeutic potential of anti-IL-33 for allergic rhinitis (AR). Twenty-four BALB/c mice were used. In group A (control group, n = 6), mice were sensitized and challenged with saline. Group B [ovalbumin (OVA) group, n = 6] mice received intraperitoneal and intranasal OVA challenge. In group C (control IgG group, n = 6), mice were injected intraperitoneally with rabbit control IgG before OVA challenge. In group D (anti-IL-33 group, n = 6), anti-IL-33 was injected before challenge. We evaluated the number of nose-scratching events and external morphology; serum total and OVA-specific IgE; number of eosinophils, neutrophils, and lymphocytes in bronchoalveolar lavage (BAL) fluid; histopathologic examination of nasal cavity; and IL-4, IL-5, and IL-13 in BAL fluid. Anti-IL-33 treatment significantly reduced the nose-scratching events and ameliorated skin denudation. Serum total and OVA-specific IgE was significantly decreased in group D. The number of eosinophils in BAL fluid was also significantly decreased. Eosinophilic infiltration in the nasal cavity was significantly decreased in group D. IL-4, IL-5, and IL-13 in BAL fluid were also significantly decreased after treatment. Anti-IL-33 antibody has a therapeutic potential for experimental AR.

Alleviation of allergic rhinitis symptoms with Pyeongwee-San extract (KMP6)

Context: Allergy is characterized by the overreaction of the immune system. Pyeongwee-San is a traditional Korean medicine which has been used for the treatment of the allergic disorder but the mechanism of action is not clear.Objective: To investigate the effect of Pyeongwee-San extract (KMP6) and its component, hesperidin (HES) in the allergic rhinitis (AR) animal model.Method: We sensitized mice on 1, 5, and 14 days by intraperitoneal injections of 100 μg ovalbumin (OVA) emulsified in 20 mg of aluminum hydroxide and we challenged mice with 1.5 mg OVA. Mice received KMP6 and HES before the intranasal OVA challenge for 10 days.Results: The number of nose rubs after the OVA challenge in the OVA-sensitized mice was significantly higher than that in the OVA-unsensitized mice. The increased number of nose rub was inhibited by the oral administration of KMP6 or HES. The increased levels of IgE and histamine level in serum of the OVA-sensitized mice were reduced by KMP6 or HES administration. The level of interferon-γ was enhanced while the level of IL-4 was reduced on the spleen tissue of the KMP6 or HES-administered AR mice. Inflammatory proteins level was reduced by KMP6 or HES administration in the nasal mucosa tissue of the OVA-sensitized mice. In the KMP6 or HES-administered mice, mast cells and eosinophils infiltration increased by OVA-sensitization was decreased.Conclusion: These results indicate that KMP6 and HES ameliorate the allergic inflammatory reactions such as AR.

Comparison of Aerosol and Intranasal Challenge in a Mouse Model of Allergic Airway Inflammation and Hyperresponsiveness

Background: The aim was to optimize antigen challenge for induction of airway hyperresponsiveness (AHR) and inflammation in BALB/c mice sensitized to ovalbumin (OVA). Comparisons were made between mice challenged with OVA either as an aerosol or intranasally. The protocol that induced maximal AHR in BALB/c mice was thereafter tested in C57BL/6 mice. Method: Methacholine responsiveness was measured using the flexiVent® system to assess AHR. Inflammatory responses were investigated by histology and cell counts in bronchoalveolar lavage (BAL) fluid. Results: 48 h after challenge with 1 or 6% OVA aerosols, there were similar increments in AHR and BAL cells, predominantly eosinophils. When comparing the effect of 1% OVA aerosol on AHR and cell infiltration at 24 and 48 h after challenge, the responses were similar. At 24 h, intranasal OVA administration (20–200 µg) caused a dose-dependent increase in AHR. BAL cells were increased by all intranasal OVA doses and to a greater extent than after 1% OVA aerosol challenge but without any dose dependency. Histological examination confirmed that there was an increase of eosinophils in lung tissue following either challenge. In C57BL/6 mice, baseline tissue elastance was the only functional outcome that was increased after intranasal OVA challenge. Even though the AHR response was negligible in C57BL/6 mice, a similar infiltration of BAL cells was observed in both strains. Conclusion: Intranasal challenge was more effective than aerosol challenge at inducing both AHR and airway inflammation in BALB/c mice. Although intranasal challenge caused airway inflammation in C57BL/6 mice, this strain is not optimal for studying AHR.