Airway Inflammation In Murine Model Research Articles

Heme Oxygenase-1-Expressing Dendritic Cells Promote Foxp3+ Regulatory T Cell Differentiation and Induce Less Severe Airway Inflammation in Murine Models.

Dendritic cells (DCs) are critical for instructing immune responses toward inflammatory or anti-inflammatory status. Heme oxygenase-1 (HO-1) is known for its cytoprotective effect against oxidative stress and inflammation, suggesting its immune regulatory role in allergic lung inflammation. HO-1 has been implicated in affecting DC maturation; however, its role in DC-mediated T-cell differentiation is unclear. In this study, we demonstrated that HO-1-expressing bone marrow-derived dendritic cells (BM-DCs) displayed tolerogenic phenotypes, including their resistance to lipopolysaccharide (LPS)-induced maturation, high level expression of IL-10, and low T-cell stimulatory activity. In addition, HO-1-expressing DCs were able to induce antigen-specific Foxp3+ regulatory T cells (Treg) differentiation in vitro and in vivo. Also, HO-1-expressing DCs modulated the severity of lung inflammatory responses in two murine models of airway inflammation. This study provided evidence supporting the role of HO-1-expressing DCs in tolerance induction and as a potential therapeutic target for allergic asthma as well as other inflammatory diseases.

Psoriatic inflammation enhances allergic airway inflammation through IL-23/STAT3 signaling in a murine model

Psoriasis is an autoimmune inflammatory skin disease characterized by activated IL-23/STAT3/Th17 axis. Recently psoriatic inflammation has been shown to be associated with asthma. However, no study has previously explored how psoriatic inflammation affects airway inflammation. Therefore, this study investigated the effect of imiquimod (IMQ)-induced psoriatic inflammation on cockroach extract (CE)-induced airway inflammation in murine models. Mice were subjected to topical and intranasal administration of IMQ and CE to develop psoriatic and airway inflammation respectively. Various analyses in lung/spleen related to inflammation, Th17/Th2/Th1 cell immune responses, and their signature cytokines/transcription factors were carried out. Psoriatic inflammation in allergic mice was associated with increased airway inflammation with concurrent increase in Th2/Th17 cells/signature cytokines/transcription factors. Splenic CD4+ T and CD11c+ dendritic cells in psoriatic mice had increased STAT3/RORC and IL-23 mRNA expression respectively. This led us to explore the effect of systemic IL-23/STAT3 signaling on airway inflammation. Topical application of STA-21, a small molecule STAT3 inhibitor significantly reduced airway inflammation in allergic mice having psoriatic inflammation. On the other hand, adoptive transfer of IL-23-treated splenic CD4+ T cells from allergic mice into naive recipient mice produced mixed neutrophilic/eosinophilic airway inflammation similar to allergic mice with psoriatic inflammation. Our data suggest that systemic IL-23/STAT3 axis is responsible for enhanced airway inflammation during psoriasis. The current study also suggests that only anti-asthma therapy may not be sufficient to alleviate airway inflammatory burden in asthmatics with psoriasis.

Th9 cells elicit eosinophil-independent bronchial hyperresponsiveness in mice

BackgroundAirway accumulation of eosinophils and bronchial hyperresponsiveness (BHR) are prominent features of bronchial asthma, though the contribution of eosinophils to the development of BHR is controversial. Similar to Th2 cell-mediated pathology, Th9 cells, characterized by IL-9-producing activity, have been demonstrated to induce airway eosinophilia and BHR. In this study, we investigated the role of eosinophils in Th9-mediated BHR by employing Th9 cell-transferred murine airway inflammation model. MethodsOvalbumin (OVA)-specific Th2 and Th9 cells were differentiated from CD4+ T cells of DO11.10/RAG-2−/− mice in vitro and cytokine-producing activity of those cells was examined. BALB/c mice were adoptively transferred with Th2 or Th9 cells and challenged with OVA. Then, the number of inflammatory cells in bronchoalveolar lavage fluid and bronchial responsiveness to inhaled methacholine were determined. ResultsBoth in Th2 and Th9 cell-transferred mice, substantial accumulation of eosinophils in the lungs and BHR were induced by challenge with specific antigen. Nevertheless, an essential and dispensable role of eosinophils in Th2- and Th9-mediated BHR, respectively, was demonstrated by employing eosinophil-deficient mice. The neutralization of IL-9 as well as deficiency of IL-10 in the donor cells did not affect Th9-mediated BHR. ConclusionsIn contrast to Th2-mediated and eosinophil-dependent BHR, Th9 could induce BHR independently from eosinophils and its characteristic cytokines, IL-9 and IL-10.

A Trypsin‐like Protease from Alternaria alternata Allergens Promotes Airway Inflammation through Activation of Protease‐activated Receptor‐2/β‐arrestin Signaling

Fungal Alternaria alternata exposure is correlated with increased morbidity and a higher risk of fatal asthma attacks in asthmatic patients. Alternaria allergens contain serine proteases capable of activating proteinase‐activated receptor‐2 (PAR2) and promote airway inflammation that is dependent upon protease activity. We have previously shown that PAR2‐dependent airway inflammation is mediated through the β‐arrestin‐2 activated pathway. Thus, we hypothesized that proteases from Alternaria filtrates will promote activation of the β‐arrestin‐2 (βarr2) dependent cellular signaling pathways that mediate airway inflammation in murine models of Alternaria‐induced asthma. We identify a single alkaline serine protease, with trypsin‐like characteristics, AASP (Alternaria Alkaline Serine Protease) that can activate PAR2, as demonstrated by recruitment of β‐arrestin‐2 to PAR2 and mobilization of intracellular Ca2+ in cultured cells. Using histological and flow cytometric analyses, we demonstrate that Alternaria‐induced airway inflammation requires both PAR2 and βarr2, as demonstrated by the reduced recruitment of leukocytes (particularly eosinophils and CD4+ T‐cells) into the lung, goblet cell hyperplasia, and thickening of the lung epithelium in PAR2−/−or βarr2−/−, compared to wild‐type mice. These inflammation parameters are also reduced by treatment of mice with Soybean Trypsin Inhibitor (SBTI) during the administration of Alternaria allergens, indicating that AASP is likely necessary for the inflammation induced by Alternaria. These are the first experiments demonstrating that the PAR2‐β‐arrestin‐dependent signaling axis is important for asthma induced by household allergens. Thus, targeting this pathway via biased antagonism of PAR2 could be a new avenue of therapeutic intervention for asthma.

Local T/B cooperation in inflamed tissues is supported by T follicular helper-like cells.

Autoimmune diseases and other inflammatory conditions are characterized by large lymphocytic tissue infiltrates in which T and B cells can be found in close contact. Here, using a murine airway inflammation model, we compare antigen-specific T and B cells in lung tissue versus lung-draining lymph node. In the lung we identify a B-cell population exhibiting a classical germinal centre phenotype without being organized into ectopic lymphoid tissue. By contrast, classical CXCR5+ Bcl-6+ T follicular helper cells are not present. Nevertheless, lung-infiltrating T cells exhibit follicular helper-like properties including the potential to provide help to naive B cells. The lung tissue is also a survival niche for memory T and B cells remaining in residual peribronchial infiltrates after resolution of inflammation. Collectively, this study shows the importance of T/B cooperation not only in lymph nodes but also in inflamed peripheral tissues for local antibody responses to infection and autoimmunity.

Chenodeoxycholic acid attenuates ovalbumin-induced airway inflammation in murine model of asthma by inhibiting the TH2 cytokines

Asthma is a complex highly prevalent airway disease that is a major public health problem for which current treatment options are inadequate. Recently, farnesoid X receptor (FXR) has been shown to exert anti-inflammatory actions in various disease conditions, but there have been no reported investigations of Chenodeoxycholic acid (CDCA), a natural FXR agonist, in allergic airway inflammation. To test the CDCA effectiveness in airway inflammation, ovalbumin (OVA)-induced acute murine asthma model was established. We found that lung tissue express FXR and CDCA administration reduced the severity of the murine allergic airway disease as assessed by pathological and molecular markers associated with the disease. CDCA treatment resulted in fewer infiltrations of cells into the airspace and peribronchial areas, and decreased goblet cell hyperplasia, mucus secretion and serum IgE levels which was increased in mice with OVA-induced allergic asthma. The CDCA treatment further blocked the secretion of TH2 cytokines (IL-4, IL-5 and IL-13) and proinflammatory cytokine TNF-α indicate that the FXR and its agonists may have potential for treating allergic asthma.

Traditional Herbal Medicine and Allergic Asthma.

The frequency of allergic diseases such as asthma and allergic rhinitis has increased rapidly during the past decade; however, the exact mechanisms have still not been established. Both air pollution and change of diet habit have been thought to play an important role in increasing prevalence of atopic diseases. Atopic diseases were mediated predominantly by type 2 T helper- (Th2-) mediated activity including allergen-specific IgE antibody and eosinophils. Allergic asthma is a chronic disease with the characteristics of immune response mediated by type 2 T helper- (Th2-) related cytokines and IgE antibody. Allergic airway inflammation has been characterized by the infiltration of Th2 cells and eosinophils, subsequently followed by the bronchial constriction and mucus secretion. Conventional treatments for allergic asthma include steroids, leukotriene antagonists, bronchodilators, and most recent anti-IgE antibody. All these drugs are still with certain shortcomings such as side effects, effectiveness, and cost. It has become more and more important to develop novel therapeutic approaches for the treatment of allergic asthma. Complementary medical approaches such Chinese herb medication and acupuncture have been suggested to play a role in the immune regulation of diseases [1]. More studies have focused on exploring the possibility of these complementary therapeutic approaches for the treatment of immunological diseases [2]. All these complimentary therapeutic approaches have been regarded as having less side effects and being used as the adjuvant therapy for the diseases [3]. Furthermore, many researchers also aim to identify the active components of herb medicine for the purification and development of drugs. In this special issue, we have five articles including the survey of traditional Chinese medicine application for the treatment of allergic asthma and also the study on the traditional Tianjiu therapy for the treatment of asthmatic patients. Furthermore, three articles on studying the active components of herb medicine have been included in the issue. S.-I. Lin et al. analyzed the use of Chinese traditional medicine for the treatment of allergic asthma in Taiwan. They collected 20,800 newly diagnosed asthmatic children and found out 20% of them actually used traditional Chinese medicine as the treatment of their asthma. In addition, they also analyzed the most frequent used herbal medicine for allergic asthma in the article. A variety of components purified from medicinal herbs have been found to exert the immune modulatory effect on many diseases [4]. Among the components, polyphenols, triterpenoids, and polysaccharides are found to be the most effective in the anti-inflammatory or immune modulation of the diseases. M.-L. Chen et al. have identified both triterpenoids and polysaccharide portion for the treatment of allergic diseases. The results showed that triterpenoids portion of Ganoderma tsugae exerted anti-inflammatory activity and polysaccharide portion had the immune stimulatory effect instead. C.-M. Ku and J.-Y. Lin also identified an active component of farnesol, a sesquiterpene alcohol, exerting anti-inflammatory activity and alleviating airway inflammation in murine model of asthma. M.-L. Chen et al. also identified ethanol extract of Perilla frutescens which also exerted anti-inflammatory activity and also alleviated allergic airway inflammation. Finally, L. Zhu et al. studied the effect of Tianjiu therapy in Sanfu Days for the treatment of asthmatic children. The results suggested that Tianjiu therapy could decrease the dose of bronchodilator during the asthma attack. However, the symptoms of allergic asthma did not show significant improvement after treatment. More studies are needed for the application of Tianjiu therapy for the treatment of allergic asthma in the future. The prevalence of clinical immunological diseases such as autoimmune diseases and allergic diseases is increasing in recent years. More and more efforts have been dedicated to develop novel therapeutic approaches for the treatment of these immune-mediated diseases. Complimentary medicine such as herb drugs or acupuncture has been suggested to be useful for the treatment of a variety of clinical immunological diseases [5]. Many of these herb medicinal components have been found to exert anti-inflammatory activity and modulation of immune response. Although more studies are needed to identify the novel compounds and the treatment, it might still be the future target for the novel therapeutic development. Particularly, these herb medicinal drugs are noted with fewer side effects, which might also be useful for possible adjuvant therapy. Bi-Fong Lin Bor-Luen Chiang Yan Ma Jin-Yuarn Lin Miaw-Ling Chen

Requirement of Apoptosis-Inducing Kinase 1 for the Induction of Bronchial Asthma following Stimulation with Ovalbumin

Background: Bronchial asthma is a chronic inflammatory disease of the airway. Apoptosis signal-regulating kinase 1 (ASK1), a member of the mitogen-activated protein kinase kinase kinase family, is activated by environmental stress and plays a crucial role in the induction of apoptosis and inflammation. To examine whether ASK1 is involved in the induction of bronchial asthma, we investigated the role of ASK1 using a genetic approach in the production of cytokines, as well as the development of airway hyperreactivity (AHR) and antibody responses using a murine airway inflammation model. Methods: ASK1-deficient (ASK1^-/-) and control wild-type (WT) mice were immunized with ovalbumin (OVA) without alum intraperitoneally, followed by intranasal administration of OVA. Airway infiltration of inflammatory cells, cytokine production, AHR and antibody production were assayed. The asthmatic phenotype was assessed following intranasal administration of IL-13 or TNF-α. Results: ASK1^-/- mice sensitized with OVA displayed an impaired inflammatory cell infiltration into airways and a decreased AHR relative to WT mice. Moreover, the production of OVA-specific IgE antibodies and proasthmatic cytokines (IL-5, IL-13 and TNF-α) was substantially reduced in OVA-stimulated ASK1^-/- mice. Intranasal administration of IL-13 and OVA enhanced the accumulation of inflammatory cells in OVA-primed ASK1^-/- mice. The OVA-induced AHR in response to methacholine was enhanced by IL-13 in WT mice but not ASK1^-/- mice. Conclusions: The ASK1 signaling pathway regulates the OVA-induced asthmatic phenotype, specifically AHR sensitivity and cytokine production. Therefore, the ASK1 signaling pathway is a promising target for therapeutic intervention in some asthmatic patients.

Extraintestinal roles of bombesin-like peptides and their receptors

Description of the recent findings of the biological roles of bombesin-like peptides and their receptors in lungs. Gastrin-releasing peptide (GRP) was involved in the airway inflammation in murine models of airway hyperreactivity. The circulating proGRP could serve as a valuable tumor marker for small-cell lung cancers, and the plasma level of proGRP is more stable compared with that of serum proGRP. Recent studies also shed light on the intracellular signaling pathways of bombesin receptor subtype-3 (BRS-3) activation in cultured human lung cancer cells. The relevant biology of BLPs and their receptors in lung cancers and other lung diseases still remains largely unknown. With the development of several highly specific BRS-3 agonists, recent studies provided some insights into the biological effects of BRS-3 in lungs.

A nematode immunomodulator suppresses grass pollen-specific allergic responses by controlling excessive Th2 inflammation

Helminth parasites modulate the immune system by complex mechanisms to ensure persistence in the host. Released immunomodulatory parasite components lead to a beneficial environment for the parasite by targeting different host cells and in parallel to a modulation of unrelated inflammatory responses in the host, such as allergy. The aim of this study was to investigate the effect of the potent helminth immunomodulator, filarial cystatin, in a murine model of airway inflammation and hyperreactivity induced by a clinically relevant aeroallergen (timothy grass (Phleum pratense) pollen) and on the function of peripheral blood mononuclear cells (PBMCs) from timothy grass pollen allergic patients. BALB/c mice were systemically sensitised with a recombinant major allergen of timothy grass pollen (rPhl p 5b) and then challenged with timothy grass pollen extract (GPE) via the airways. Filarial cystatin was applied i.p. during the sensitisation phase. Airway hyperresponsiveness to methacholine challenges, inflammation of airways, inflammatory cell recruitment, cytokine production and lung histopathology were investigated. In a translational approach, PBMCs from allergic subjects and healthy controls were treated in vitro with cystatin prior to stimulation with GPE. Administration of filarial cystatin suppressed rPhl p 5b-induced allergen-specific Th2-responses and airway inflammation, inhibited local recruitment of eosinophils, reduced levels of allergen-specific IgE and down-regulated IL-5 and IL-13 in the bronchoalveolar lavage (BAL). Ex vivo restimulation with cystatin of spleen cells from cystatin-treated mice induced the production of IL-10, while cystatin inhibited allergen-specific IL-5 and IL-13 levels. Human PBMCs from timothy grass pollen allergic patients displayed a shift towards a Th1 response after treatment with cystatin. These results show that filarial cystatin ameliorates allergic inflammation and disease in a clinically relevant model of allergy. This data indicate that filarial cystatin has a modulatory effect on grass pollen-specific responses warranting further investigation of potential preventive and therapeutic options in the treatment of allergies.

Milk-CLA is a biomarker for traditional farm milk but is not responsible for the allegro-protective farm milk effect in a murine model of airway inflammation

Milk-CLA is a biomarker for traditional farm milk but is not responsible for the allegro-protective farm milk effect in a murine model of airway inflammation

Schistosoma mansoni Venom Allergen Like Proteins Present Differential Allergic Responses in a Murine Model of Airway Inflammation

BackgroundThe Schistosoma mansoni Venom-Allergen-Like proteins (SmVALs) are members of the SCP/TAPS (Sperm-coating protein/Tpx-1/Ag5/PR-1/Sc7) protein superfamily, which may be important in the host-pathogen interaction. Some of these molecules were suggested by us and others as potential immunomodulators and vaccine candidates, due to their functional classification, expression profile and predicted localization. From a vaccine perspective, one of the concerns is the potential allergic effect of these molecules.Methodology/Principal FindingsHerein, we characterized the putative secreted proteins SmVAL4 and SmVAL26 and explored the mouse model of airway inflammation to investigate their potential allergenic properties. The respective recombinant proteins were obtained in the Pichia pastoris system and the purified proteins used to produce specific antibodies. SmVAL4 protein was revealed to be present only in the cercarial stage, increasing from 0–6 h in the secretions of newly transformed schistosomulum. SmVAL26 was identified only in the egg stage, mainly in the hatched eggs' fluid and also in the secretions of cultured eggs. Concerning the investigation of the allergic properties of these proteins in the mouse model of airway inflammation, SmVAL4 induced a significant increase in total cells in the bronchoalveolar lavage fluid, mostly due to an increase in eosinophils and macrophages, which correlated with increases in IgG1, IgE and IL-5, characterizing a typical allergic airway inflammation response. High titers of anaphylactic IgG1 were revealed by the Passive Cutaneous Anaphylactic (PCA) hypersensitivity assay. Additionally, in a more conventional protocol of immunization for vaccine trials, rSmVAL4 still induced high levels of IgG1 and IgE.ConclusionsOur results suggest that members of the SmVAL family do present allergic properties; however, this varies significantly and therefore should be considered in the design of a schistosomiasis vaccine. Additionally, the murine model of airway inflammation proved to be useful in the investigation of allergic properties of potential vaccine candidates.

Thiazolidinediones Improve Asthma Control In Diabetic Asthmatics

RATIONALE: Thiazolidinediones (TZD) have potent anti-inflammatory actions and improve airway inflammation in murine models of allergic inflammation. The impact of TZD on human asthma is not well known. The purpose of this study was to investigate the influence of TZD on asthma severity and morbidity in a large well characterized human population.

Aclidinium bromide abrogates allergen-induced hyperresponsiveness and reduces eosinophilia in murine model of airway inflammation

Airway hyperresponsiveness and inflammation characterize the airways of individuals with asthma and chronic obstructive pulmonary disease (COPD). Hence, therapeutic approaches that attenuate such manifestations may offer promise in the management of these diseases. In the present study, we investigated whether a novel long-acting cholinergic antagonist, aclidinium bromide, modulates airway function and leukocyte trafficking in an Aspergillus fumigatus ( Af)-induced murine model of asthma. Nebulized aclidinium (1 mg/ml) administration completely abrogated increases in methacholine-induced lung resistance in Af-exposed mice. Parallel assessment of dynamic compliance showed that aclidinium also completely restores methacholine-mediated decreases in naïve and Af-exposed mice. As evidenced by differential cell counts within bronchoalveolar lavage fluid, aclidinium also diminished (51 ± 4%) Af-induced airway eosinophil numbers with no significant change in other immune cell types. Further assessment of cytokine and total protein levels in bronchoalveolar lavage fluid showed that aclidinium had little effect on IL-4 or IL-6 levels in either Af-exposed or naïve mice but markedly decreased total protein levels in bronchoalveolar lavage fluid. These data suggest that aclidinium, a selective muscarinic antagonist, not only acts as a bronchodilator but could also act as an anti-inflammatory agent with potential clinical benefits in the treatment of COPD and asthma.

Increased poly(ADP-ribose) polymerase (PARP)-1 expression and activity are associated with inflammation but not goblet cell metaplasia in murine models of allergen-induced airway inflammation

ABSTRACTInflammation plays a key role in lung injury and in the pathogenesis of asthma. Two murine models of allergic airway inflammation—sensitization and challenge to ovalbumin (OVA) and intratracheal exposure to interleukin-13 (IL13)—were used to evaluate the expression of poly(ADP-ribose) polymerase-1 (PARP-1) in allergic airway inflammation. Inflammation is prominent in OVA-induced allergic asthma, but this inflammation is greatly reduced by a PARP-1 inhibitor and almost eliminated when PARP-1 knockout mice are subjected to the OVA model. The present study temporally evaluated PARP-1 protein expression, localization, and activity, as well as inflammation and goblet cell metaplasia (GCM), in murine lungs following a single OVA challenge or IL13 exposure. Following OVA challenge PARP-1 protein expression and activity were greatly increased, being maximal at 3 to 5 days following OVA exposure and beginning to decrease by day 8. These changes correlated with the timing and degree of inflammation and GCM. In contrast, PARP-1 protein or activity did not change following single IL13 exposure, though GCM was manifested without inflammation. This study demonstrates that both PARP-1 protein and activity are increased by allergen-activated inflammatory mediators, excluding IL13, and that PARP-1 increase does not appear necessary for GCM, one of the characteristic markers of allergic airway inflammation in murine models.

Dietary Supplementation with Fructooligosaccharides Attenuates Airway Inflammation Related to House Dust Mite Allergen in Mice

Fructooligosaccharides (FOS) are prebiotic supplements that can enhance immunological responses in the host to activate mucosal immunity, probably through regulation of gastrointestinal microflora. An area that has not been investigated, however, is the therapeutic potential of prebiotics on allergic airway diseases. The purpose of this study is to evaluate the effects of dietary supplementation with FOS on a murine model of allergic airway inflammation induced by the house dust mite allergen Dermatophagoides farinae (Der f). Male C3H/HeN mice were intratracheally administered with Der f and were fed a diet containing 0% or 2.5% FOS ad libitum. Supplementation with FOS alleviated mite allergen-related airway inflammation characterized by eosinophilic inflammation and goblet cell hyperplasia, which was evidenced by cytological and histological examinations. In addition, the FOS-supplemented diet reduced the serum allergen-specific IgG1 level as compared with a control diet in the presence of the mite allergen. Moreover, FOS tended to suppress the expression of IL-5 and eotaxin in the lungs, which is enhanced by mite allergen. These results suggest that dietary supplementation with FOS can prevent/improve allergic airway inflammation induced by the mite allergen. This effect can be at least partially associated with the inhibition of allergen-specific Ig production and probably with that of IL-5 and eotaxin expression.

Schistosoma mansoniantigens modulate the allergic response in a murine model of ovalbumin-induced airway inflammation

Schistosoma mansoni infection has been associated with protection against allergies. The mechanisms underlying this association may involve regulatory cells and cytokines. We evaluated the immune response induced by the S. mansoni antigens Sm22.6, PIII and Sm29 in a murine model of ovalbumin (OVA)-induced airway inflammation. BALB/c mice were sensitized with subcutaneously injected OVA-alum and challenged with aerolized OVA. Mice were given three doses of the different S. mansoni antigens. Lung histopathology, cellularity of bronchoalveolar lavage (BAL) and eosinophil peroxidase activity in lung were evaluated. Immunoglobulin (Ig)E levels in serum and cytokines in BAL were also measured. Additionally, we evaluated the frequency of CD4+forkhead box P3 (FoxP3)+ T cells in cultures stimulated with OVA and the expression of interleukin (IL)-10 by these cells. The number of total cells and eosinophils in BAL and the levels of OVA-specific IgE were reduced in the immunized mice. Also, the levels of IL-4 and IL-5 in the BAL of mice immunized with PIII and Sm22.6 were decreased, while the levels of IL-10 were higher in mice immunized with Sm22.6 compared to the non-immunized mice. The frequency of CD4+FoxP3+ T cells was higher in the groups of mice who received Sm22.6, Sm29 and PIII, being the expression of IL-10 by these cells only higher in mice immunized with Sm22.6. We concluded that the S. mansoni antigens used in this study are able to down-modulate allergic inflammatory mediators in a murine model of airway inflammation and that the CD4+FoxP3+ T cells, even in the absence of IL-10 expression, might play an important role in this process.

Development of a Murine Model of Airway Inflammation and Remodeling in Experimental Asthma

Background and Objective Experimental animal models are necessary for studying asthma disease mechanisms and for identifying new therapeutic targets. We present a murine model of experimental asthma that allows integrated, quantitative assessment of airway inflammation and remodeling. Material and Methods BALB/c mice were sensitized to ovalbumin (OVA) and challenged with OVA or vehicle 3 times per week for 12 weeks. Results On bronchoalveolar lavage, the OVA-sensitized mice had significantly higher total leukocyte counts, with a median (Q25-Q75) of 670.0 cells/mL×10 -3 (376.2-952.5) in comparison with 40.0 cells/ mL×10 -3 (60.0-85.0) in controls ( P=.001), and higher eosinophil and differential lymphocyte counts. In sagittal sections of lungs inflated to a standard pressure, the OVA-sensitized animals showed goblet cell hyperplasia in the respiratory epithelium (periodic acid-Schiff staining, 53.89 [36.26-62.84] cells/mm 2 vs 0.66 [0.00-1.06] cells/mm 2, P<.001), dense mononuclear and eosinophilic inflammatory infiltrates (hematoxylin-eosin, 32.87 [27.34-37.13] eosinophils/mm 2 vs 0.06 [0.00-0.20] eosinophils/mm 2, P=.002), subepithelial infiltration by mast cells (toluidine blue, 2.88 [2.00-3.28] mast cells/mm 2 vs 0.28 [0.15-0.35] mast cells/mm 2, P<.001), increased contractile tissue mass (immunofluorescence analysis for α-smooth-muscle actin, 2.60 [2.28-2.98] vs 1.08 [0.93-1.16], dimensionless, P<.001) and enhanced extracellular matrix deposition (Masson's trichrome, 2.18 [1.85-2.80] vs 0.50 [0.37-0.65], dimensionless, P<.001). Conclusions Our dataset describes an experimental model of asthma which is driven by prolonged allergen exposure and in which airway inflammation and remodeling develop and are assessed together.

Effects of Surfactant Protein D (SP-D) on Dendritic Cell Subtypes in the Lung in Mice

RATIONALE: In murine models of airway inflammation it was shown that unlike the tolerogenic plasmocytoid dendritic cells, myeloid (bone-marrow derived) dendritic cells are central in promoting the allergic airway response. The role of SP-D in regulating presence of dendritic cell subtypes in the lung is unclear. METHODS: Cytokine and SP-D protein and mRNA expression was assessed by ELISA, Western blot and real-time PCR, respectively, using in vivo models of allergic airway sensitization. Macrophage and dendritic cell phenotypes and intracellular TNFa expression were analyzed by FACS. Maturation of ckit+ bone-marrow derived dendritic cells was investigated in vitro. Migration was studied by PKH26 uptake in vivo. RESULTS: TARC (thymus and activation regulated chemokine, responsible for attracting activated dendritic cells) showed an early upregulation in the airways followed by a resolution after allergen challenge of wild-type mice. SP-D-/- animals however had a constitutive TARC expression in the BAL fluid. Intraperitoneal PKH26 injection revealed a preferential accumulation of phagocytic cells in the lungs of SP-D-/- mice in comparison with wild-type animals. Bronchoalveolar lavage cells of SP-D-/- mice had increased numbers of activated, TNFα- and TARC expressing, myeloid dendritic cells. Recombinant SP-D significantly suppressed MHC class-II, CD86 and CD11b as well as intracellular TNFα in bone marrow-derived (myeloid) dendritic cell cultures in vitro. CONCLUSIONS: Presence of SP-D in the lung is important to prevent constitutive migration and activation of proinflammatory myeloid dendritic cells. Such negative regulation may facilitate resolution of acute inflammatory changes and prevents development of chronic conditions such as asthma.

The Preventive Effect of Lactobacillus rhamnosus on the Development of Allergic Airway Inflammation in Murine Model

The Preventive Effect of Lactobacillus rhamnosus on the Development of Allergic Airway Inflammation in Murine Model