Project description:Obesity is associated with severe, difficult to control asthma, and increased airway oxidative stress. Mitochondrial reactive oxygen species (mROS) are an important source of oxidative stress leading us to hypothesize that targeting mROS in obese allergic asthma might be an effective treatment strategy. Using a mouse model of house dust mite (HDM) induced allergic airway disease in mice fed a low- (LFD) or high-fat diet (HFD), and the mitochondrial antioxidant MitoQuinone (MitoQ); we investigated the effects of obesity and mROS on airway inflammation, remodelling and airway hyperreactivity (AHR). HDM induces airway inflammation, remodelling and hyperreactivity in both lean and obese mice. Obese allergic mice showed increased lung tissue eotaxin levels, airway tissue eosinophilia and AHR when compared to lean allergic mice. MitoQ reduced markers of airway inflammation, remodelling and hyperreactivity in both lean and obese allergic mice, and tissue eosinophilia in obeseHDM mice. mROS regulates cell signalling by protein oxidation of multiple downstream targets: MitoQ reduced HDM-induced cysteine-sulfenylation of several proteins including those involved in the unfolded protein response (UPR). In summary, mROS mediates the development of allergic airway disease and hence MitoQ might be effective for the treatment for asthma, and specific features of obese asthma.
Project description:This SuperSeries is composed of the following subset Series: GSE35979: Gene expression data from IL13-induced allergic airway inflammation of mice lungs GSE35980: MicroRNA expression data from IL13-induced allergic airway inflammation of mice lungs GSE37079: Methylated DNA immunoprecipitation (MeDIP) microarray data from IL13-induced allergic airway inflammation of mouse lungs Refer to individual Series
Project description:Fungal spores, abundant in the environment, are a major cause of asthma. But the precise host response that triggers fungal allergic airway inflammation remains unclear. We found that CD11c+ DCs and CD4+ T cells are essential for development of airway inflammation in mice when repeatedly exposed to inhaled spores. To delinate which DC subsets are mediating fungal allergic inflammation we undertook single cell RNAseq of DCs isolated from the lungs of mice exposed to fungal spores. This identified precise subsets altered upon spore exposure and following targeted removal identified distinct DC subsets (Mgl2+ cDC2s) that are essential for fungal allergic airway inflammation.
Project description:Background: A specific subset of regulatory IL-10 producing B cells has been extensively studied in autoimmune and inflammatory pathologies. These cells are able to constrain exacerbated inflammation by inhibiting T cell mediated responses and maturation of antigen presenting cells. In allergic diseases, observations that increase of regulatory B cells is necessary for allergen tolerance suggest that development of allergic asthma would be associated with a defect in the regulatory B cells compartment. Objective: We sought to (i) characterize regulatory IL-10+ regulatory B cell subset in Balb/c mice by microarray and flow cytometry and (ii) investigate their regulatory capacity in vivo in a house dust mite model of allergic asthma. Results: We identified an IL-10 producing B cells subset able to control T cell proliferation in vitro in both control and asthmatic mice. This subset is decreased in allergic mice. IL-10+ Breg cells express high levels of CD9 and upregulate CD70 and CD73 after activation. Expression of CD9 allows identifying more than 50% of Bregs. Interestingly CD9+ B cells inhibit TH2-TH17 allergic airway inflammation in vivo after adoptive transfer in an IL-10 dependent manner. Conclusions: Herein, we demonstrate that induction of allergic asthma dampens the generation of Bregs contributing to exacerbated airway inflammation. We identified a distinct CD9+ Breg-cell population decreased in lung of HDM mice and able to control asthma and allergic airway inflammation by producing IL-10 after adoptive transfer. This study points B cells as an interesting therapeutic target in allergic asthma. IL-10+ B cells (n=3) and 3 IL-10- B cells (n=3) in control mice + IL-10+ B cells (n=3) and 3 IL-10- B cells (n=3) from asthmatic allergic (HDM) mice
Project description:Asthma is a common chronic inflammatory airway condition with a strong genetic and inheritability component, as siblings and first-degree relatives of those with the disease are often affected. For our studies, we used a well-characterized transgenic mouse model of allergic airway inflammation induced by IL13. In this model, IL13 is conditionally overexpressed in the mouse lung when treated with doxycycline. Upon IL13 induction, these mice showed inflammatory cell infiltration, pronounced emphysema, increased pulmonary compliance, lung volume enlargement, mucus metaplasia, and increased expression of matrix metalloproteinases and cathepsins in the lung. We performed gene expression microarray to examine the changes in gene expression during IL13-induced allergic airway inflammation. The CC10-rtTA-IL13 transgenic (TG) and wildtype (WT) mice were treated with doxycycline for seven days. Mice were euthanized and the left upper lobes from all mice were removed for RNA extraction using the TRIzol method.
Project description:DJ-1 is an antioxidant protein known to regulate mast cell mediated allergic response, but its role in airway eosinophilic interactions and allergic inflammation is not known.
Project description:Background DJ-1 is an antioxidant protein known to regulate mast cell mediated allergic response, but its role in airway eosinophilic interactions and allergic inflammation is not known. Objective The aim of this study was to investigate the role of DJ-1 in airway eosinophilic inflammation in vitro and in vivo. Methods Ovalbumin-induced airway allergic inflammation was established in mice. ELISA was adopted to analyze DJ-1 and cytokine levels in mouse bronchoalveolar lavage fluid. Transcriptional profiling of mouse lung tissues was conducted by single-cell RNA sequencing technology. The role of DJ-1 in the differentiation of airway progenitor cells into goblet cells was examined by organoid cultures, immunofluorescence staining, quantitative PCR, and cell transplantation in normal, DJ-1 knockout (KO), or conditional DJ-1 KO mice. Results We observed that DJ-1 was increased in the lung tissues of ovalbumin-sensitized and challenged mice. DJ-1 KO mice exhibited reduced airway eosinophil infiltration and goblet cell differentiation. Mechanistically, we discovered that eosinophil-club cell interactions are reduced in the absence of DJ-1. Organoid cultures indicated that eosinophils impair the proliferative potential of club cells. Intratracheal transplantation of DJ-1-deficient eosinophils suppresses airway goblet cell differentiation. Loss of DJ-1 inhibits the metabolism of arachidonic acid into cysteinyl leukotrienes in eosinophils while these secreted metabolites promote airway goblet cell fate in organoid cultures and in vivo. Conclusion DJ-1-mediated interactions between airway epithelial progenitor cells and immune cells are essential in controlling airway goblet cell metaplasia and eosinophilia. Blockade of the DJ-1 pathway is protective against airway allergic inflammation.
Project description:Epigenetic changes have been implicated in pathogenesis of asthma. We sought to determine if IL13, a key cytokine in airway inflammation and remodeling, induced epigenetic DNA methylation changes in the airways in conjunction with its transcriptional gene regulation. For our studies, we used a well-characterized transgenic mouse model of allergic airway inflammation induced by IL13. In this model, IL13 is conditionally overexpressed in the mouse lung when treated with doxycycline. Upon IL13 induction, these mice showed inflammatory cell infiltration, pronounced emphysema, increased pulmonary compliance, lung volume enlargement, mucus metaplasia, and increased expression of matrix metalloproteinases and cathepsins in the lung. We performed MeDIP microarray to examine the changes in DNA promoter methylation during IL13-induced allergic airway inflammation. The CC10-rtTA-IL13 transgenic (TG) and wildtype (WT) mice were treated with doxycycline for seven days. Mice were euthanized and the left lower lobes from all mice were removed for DNA extraction followed by MeDIP array analysis.
Project description:Rationale: Aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, has been considered as an important regulator for immune diseases. We have previously shown that AhR protects against allergic airway inflammation. The underlying mechanism, however, remains undetermined. Objectives: We sought to determine whether AhR specifically in Type II alveolar epithelial cells (AT2) modulates allergic airway inflammation and its underlying mechanisms. Methods: The role of AhR in AT2 cells in airway inflammation was investigated in a mouse model of asthma with AhR conditional knock out mice in AT2 cells (Sftpc-Cre;AhRflox/flox). The effect of AhR on allergen-induced autophagy was examined by both in vivo and in vitro analyses. The involvement of autophagy in airway inflammation was analyzed by using autophagy inhibitor chloroquine. The AhR-regulated gene profiling in AT2 cells was also investigated by RNA-seq analysis. Results: Sftpc-Cre; AhRflox/flox mice showed exacerbation of allergen-induced airway hyperresponsiveness and airway inflammation with elevated Th2 and airway epithelial-derived cytokines in bronchoalveolar lavage fluid (BALF). Notably, an increased allergen-induced autophagy was observed in the lung tissues of Sftpc-Cre; AhRflox/flox mice when compared with wild-type mice. Further analyses suggested a functional axis of AhR-TGF-β1 that is critical in driving allergic airway inflammation through regulating allergen-induced cellular autophagy. Furthermore, inhibition of autophagy suppressed allergic airway inflammation with decreased Th2 and epithelial cell-derived cytokines in BALFs. Additionally, RNA-seq analysis suggests that autophagy is one of the major pathways and CALCOCO2/NDP52 and S1009 are major autophagy-associated genes in AT2 cells that contribute to the AhR-mediated allergic airway inflammation. Conclusion: These results suggest that AhR in AT2 cells functions as a protective mechanism against allergic airway inflammation through controlling cell autophagy.