| 1. |
- Cerps, Samuel, et al.
(författare)
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House dust mite sensitization and exposure affects bronchial epithelial anti-microbial response to viral stimuli in patients with asthma
- 2022
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Ingår i: Allergy: European Journal of Allergy and Clinical Immunology. - : Wiley. - 0105-4538. ; 77:8, s. 2498-2508
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Allergen exposure worsens viral-triggered asthma exacerbations and could predispose the host to secondary bacterial infections. We have previously demonstrated that exposure to house dust mite (HDM) reduced TLR-3-induced IFN-β in human bronchial epithelial cells (HBECs) from healthy donors. We hypothesize that HDM sensitization in different ways may be involved in both viral and bacterial resistance of HBECs in asthma. In this study, the role of HDM sensitization and effects of HDM exposure on viral stimulus-challenged HBECs from asthmatic donors have been explored with regard to expression and release of molecules involved in anti-viral and anti-bacterial responses, respectively. Methods: HBECs from HDM-sensitized (HDM+) and unsensitized (HDM-) patients with asthma were used. HBECs were exposed to HDM or heat inactivated (hi)-HDM (20 μg/ml) for 24 h prior to stimulation with the viral infection mimic, Poly(I:C), for 3 or 24 h. Samples were analyzed with ELISA and RT-qPCR for β-defensin-2, IFN-β, TSLP, and neutrophil-recruiting mediators: IL-8 and TNF-⍺. NFκB signaling proteins p105, p65, and IκB-⍺ were analyzed by Western blot. Results: Poly(I:C)-induced IFN-β expression was reduced in HBECs from HDM + compared to HDM- patients (p = 0.05). In vitro exposure of HBECs to HDM furthermore reduced anti-microbial responses to Poly(I:C) including β-defensin-2, IL-8, and TNF-⍺, along with reduced NFκB activity. This was observed in HBECs from asthma patients sensitized to HDM, as well as in non-sensitized patients. By contrast, Poly (I:C)-induced release of TSLP, a driver of T2 inflammation, was not reduced with exposure to HDM. Conclusion: Using HBECs challenged with viral infection mimic, Poly(I:C), we demonstrated that allergic sensitization to HDM was associated with impaired anti-viral immunity and that HDM exposure reduced anti-viral and anti-bacterial defense molecules, but not TSLP, across non-allergic as well as allergic asthma. These data suggest a role of HDM in the pathogenesis of asthma exacerbations evoked by viral infections including sequential viral-bacterial and viral-viral infections.
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| 2. |
- Menzel, Mandy, et al.
(författare)
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Oxidative Stress Attenuates TLR3 Responsiveness and Impairs Anti-viral Mechanisms in Bronchial Epithelial Cells From COPD and Asthma Patients
- 2019
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- COPD and asthma exacerbations are commonly triggered by rhinovirus infection. Potentially promoting exacerbations, impaired anti-viral signaling and attenuated viral clearance have been observed in diseased bronchial epithelium. Oxidative stress is a feature of inflammation in asthma and COPD and is prominent during exacerbations. It is not known whether oxidative stress affects the anti-viral signaling capacity. Bronchial epithelial cells from asthmatic and COPD donors were infected with rhinovirus or treated with the oxidative stressor H2O2 followed by exposure to the synthetic viral replication intermediate poly(I:C). Poly(I:C) was used to ascertain a constant infection-like burden. Gene and protein levels of antioxidants as well as anti-viral responses were measured 3 and 24 h post poly(I:C) exposure. Rhinovirus infection and poly(I:C) stimulation induced protein levels of the antioxidants SOD1 and SOD2. In asthmatic bronchial epithelial cells pre-treatment with H2O2 dose-dependently decreased the antioxidant response to poly(I:C), suggesting exaggerated oxidative stress. Further, poly(I:C)-induced IFN beta gene expression was reduced after pre-treatment with H2O2. This epithelial effect was associated with a reduced expression of the pattern recognition receptors RIG-I, MDA5 and TLR3 both on gene and protein level. Pre-treatment with H2O2 did not alter antioxidant responses in COPD bronchial epithelial cells and, more modestly than in asthma, reduced poly(I:C)-induced IFN beta gene expression. Knockdown of TLR3 but not RIG-I/MDA5 abrogated impairment of poly(I:C)-induced IFN beta gene expression by H2O2. We developed a method by which we could demonstrate that oxidative stress impairs anti-viral signaling in bronchial epithelial cells from asthmatic and COPD patients, most pronounced in asthma. The impairment apparently reflects reduced responsiveness of TLR3. These present findings shed light on molecular mechanisms potentially causing reduced interferon responses to rhinovirus infection at exacerbations in asthma and COPD. Together, our findings suggest a possible self-perpetuating vicious cycle underlying recurrent exacerbations, leading to an impaired anti-viral response, which in turn leads to viral-induced exacerbations, causing more airway inflammation.
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| 3. |
- Brandelius, Angelica, et al.
(författare)
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dsRNA-induced expression of thymic stromal lymphopoietin (TSLP) in asthmatic epithelial cells is inhibited by a small airway relaxant.
- 2011
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Ingår i: Pulmonary Pharmacology & Therapeutics. - : Elsevier BV. - 1522-9629 .- 1094-5539. ; 24, s. 59-66
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Tidskriftsartikel (refereegranskat)abstract
- RATIONALE: Thymic Stromal Lymphopoietin (TSLP) is considered a hub cytokine that activates dendritic cells and T-cells producing asthma-like Th(2)-inflammation. Viral stimuli, a major cause of asthma exacerbations, have been shown to induce overexpression of TSLP in asthmatic epithelium. Capsazepine has multiple effects and is of interest because it relaxes human small airways. Here we have explored effects of capsazepine on viral surrogate (dsRNA)-induced TSLP and other cytokines (TNF-alpha, IL-8) in human bronchial epithelial cells (HBEC) from healthy and asthmatic donors. METHODS: HBEC obtained from healthy and asthmatic subjects were grown and stimulated with dsRNA. Cells pre-treated with capsazepine (3-30μM), dexamethasone (0.1-10μM) or an IkappaB-kinase inhibitor (PS1145, 30μM) were also exposed to dsRNA (10μg/ml). Cells and supernatants were harvested for analyses of gene expression (RT-qPCR) and protein production (ELISA,Western blot). RESULTS: dsRNA-induced TSLP, TNF-alpha, and IL-8 in asthmatic and non-asthmatic HBEC. Dexamethasone attenuated gene expression and protein release whereas capsazepine dose-dependently, and similar to a non-relaxant NFkB inhibitor (PS1145), completely inhibited dsRNA-induced TSLP and TNF-alpha in both healthy and asthmatic HBEC. Capsazepine reduced dsRNA-induced IL-8 and it prevented dsRNA-induced loss of the NF-κB repressor protein IkBα. CONCLUSION: Additional to its human small airway relaxant effects we now demonstrate that capsazepine has potent anti-inflammatory effects on viral stimulus-induced cytokines in HBEC from healthy as well as asthmatic donors. Based on these data we suggest that exploration of structure-activity amongst the multifaceted capsazepinoids is warranted in search for compounds of therapeutic value in viral-induced, steroid-resistant asthma.
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| 4. |
- Mogren, Sofia, et al.
(författare)
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Mast cell tryptase enhances wound healing by promoting migration in human bronchial epithelial cells
- 2021
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Ingår i: Cell Adhesion and Migration. - : Informa UK Limited. - 1933-6918 .- 1933-6926. ; 15:1, s. 202-214
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Tidskriftsartikel (refereegranskat)abstract
- Epithelial damage and increase of intraepithelial mast cells (MC) are characteristics of asthma. The role of MC mediator tryptase and the protease-activated receptor-2 (PAR2) on epithelial wound healing is not fully investigated. Stimulation of bronchial epithelial cells (BECs) with tryptase promoted gap closure, migration and cellular speed compared to controls. Stimulated BECs had higher expression of migration marker CD151 compared to controls. Proliferation marker KI67 was upregulated in tryptase-stimulated BECs compared to controls. Treatment with PAR2 antagonist I-191 reduced gap closure, migration and cell speed compared to BECs stimulated with tryptase. We found that tryptase enhances epithelial wound healing by increased migration and proliferation, which is in part regulated via PAR2. Our data suggest that tryptase might be beneficial in tissue repair under baseline conditions. However, in a pathological context such as asthma with increased numbers of activated MCs, it might lead to epithelial remodeling and loss of function.
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| 5. |
- Bodahl, Sara, et al.
(författare)
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LL-37 and Double-Stranded RNA Synergistically Upregulate Bronchial Epithelial TLR3 Involving Enhanced Import of Double-Stranded RNA and Downstream TLR3 Signaling
- 2022
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Ingår i: Biomedicines. - : MDPI AG. - 2227-9059. ; 10:2
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Tidskriftsartikel (refereegranskat)abstract
- The human host defense peptide LL-37 influences double-stranded RNA signaling, but this process is not well understood. Here, we investigate synergistic actions of LL-37 and synthetic double-stranded RNA (poly I:C) on toll-like receptor 3 (TLR3) expression and signaling, and examine underlying mechanisms. In bronchial epithelial BEAS-2B cells, LL-37 potentiated poly I:C-induced TLR3 mRNA and protein expression demonstrated by qPCR and Western blot, respectively. Interestingly, these effects were associated with increased uptake of rhodamine-tagged poly I:C visualized by immunocytochemistry. The LL-37/poly I:C-induced upregulation of TLR3 mRNA expression was prevented by the endosomal acidification inhibitor chloroquine, indicating involvement of downstream TLR3 signaling. The glucocorticoid dexamethasone reduced LL-37/poly I:C-induced TLR3 expression on both mRNA and protein levels, and this effect was associated with increased IκBα protein expression, suggesting that dexamethasone acts via attenuation of NF-κB activity. We conclude that LL-37 potentiates poly I:C-induced upregulation of TLR3 through a mechanism that may involve enhanced import of poly I:C and that LL-37/poly I:C-induced TLR3 expression is associated with downstream TLR3 signaling and sensitive to inhibition of NF-κB activity.
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| 6. |
- Uller, Lena, et al.
(författare)
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Antagonism of the prostaglandin D2 receptor CRTH2 attenuates asthma pathology in mouse eosinophilic airway inflammation.
- 2007
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Ingår i: Respiratory Research. - : Springer Science and Business Media LLC. - 1465-9921 .- 1465-993X. ; 8:16
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Tidskriftsartikel (refereegranskat)abstract
- Background: Mast cell-derived prostaglandin D-2 (PGD(2)), may contribute to eosinophilic inflammation and mucus production in allergic asthma. Chemoattractant receptor homologous molecule expressed on TH2 cells (CRTH2), a high affinity receptor for prostaglandin D-2, mediates trafficking of TH2-cells, mast cells, and eosinophils to inflammatory sites, and has recently attracted interest as target for treatment of allergic airway diseases. The present study involving mice explores the specificity of CRTH2 antagonism of TM30089, which is structurally closely related to the dual TP/CRTH2 antagonist ramatroban, and compares the ability of ramatroban and TM30089 to inhibit asthma-like pathology. Methods: Affinity for and antagonistic potency of TM30089 on many mouse receptors including thromboxane A(2) receptor mTP, CRTH2 receptor, and selected anaphylatoxin and chemokines receptors were determined in recombinant expression systems in vitro. In vivo effects of TM30089 and ramatroban on tissue eosinophilia and mucus cell histopathology were examined in a mouse asthma model. Results: TM30089, displayed high selectivity for and antagonistic potency on mouse CRTH2 but lacked affinity to TP and many other receptors including the related anaphylatoxin C3a and C5a receptors, selected chemokine receptors and the cyclooxygenase isoforms 1 and 2 which are all recognized players in allergic diseases. Furthermore, TM30089 and ramatroban, the latter used as a reference herein, similarly inhibited asthma pathology in vivo by reducing peribronchial eosinophilia and mucus cell hyperplasia. Conclusion: This is the first report to demonstrate anti-allergic efficacy in vivo of a highly selective small molecule CRTH2 antagonist. Our data suggest that CRTH2 antagonism alone is effective in mouse allergic airway inflammation even to the extent that this mechanism can explain the efficacy of ramatroban.
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| 7. |
- Akbarshahi, Hamid, et al.
(författare)
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House dust mite impairs antiviral response in asthma exacerbation models through its effects on TLR3
- 2018
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Ingår i: Allergy. - : Wiley. - 1398-9995 .- 0105-4538. ; 73:5, s. 1053-1063
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Impaired antiviral interferon expression may be involved in asthma exacerbations commonly caused by rhinovirus infections. Allergy is a known risk factor for viral-induced asthma exacerbation, but little is known whether allergens may affect interferon responses.OBJECTIVE: Our hypothesis is that house dust mite (HDM) impairs viral stimulus-induced antiviral signalling.METHODS: Experimental asthma exacerbations were produced in vitro in human bronchial epithelial cells (HBECs) and in mice by using sequential challenges with HDM and a viral infection mimic, Poly(I:C). We examined rhinovirus pattern recognition receptors (PRRs) signalling pathways and potential mechanisms of impaired interferon response.RESULTS: HBECs and mice exposed to HDM prior to Poly(I:C) exhibited a reduced antiviral response compared to Poly(I:C) alone, including reduced IFN-β, IFN-lambda, TLR3, RIG-I, MDA5, IRF-3 and IRF-7. Heat-inactivation of HDM partially restored the TLR3-induced interferon response in vitro and in vivo. Our HBEC-data further showed that HDM directly affects TLR3 signalling by targeting the receptor glycosylation level.CONCLUSIONS: Direct effects of allergens such as HDM on PRRs can present as potential mechanism for defective antiviral airway responses. Accordingly, therapeutic measures targeting inhibitory effects of allergens on antiviral PRRs may find use as a strategy to boost antiviral response and ameliorate exacerbations in asthmatic patients. This article is protected by copyright. All rights reserved.
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| 8. |
- Andreasson, Louise Munkholm, et al.
(författare)
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Airway hyperresponsiveness correlates with airway TSLP in asthma independent of eosinophilic inflammation
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Ingår i: Journal of Allergy and Clinical Immunology. - 0091-6749.
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Tidskriftsartikel (refereegranskat)abstract
- Background: Thymic stromal lymphopoietin (TSLP) is released from the airway epithelium in response to various environmental triggers, inducing a type-2 inflammatory response, and is associated with airway inflammation, airway hyperresponsiveness (AHR), and exacerbations. TSLP may also induce AHR via a direct effect on airway smooth muscle and mast cells, independently of type-2 inflammation, although association between airway TSLP and AHR across asthma phenotypes has been described sparsely. Objectives: This study sought to investigate the association between AHR and levels of TSLP in serum, sputum, and bronchoalveolar lavage in patients with asthma with and without type-2 inflammation. Methods: A novel ultrasensitive assay was used to measure levels of TSLP in patients with asthma (serum, n = 182; sputum, n = 81; bronchoalveolar lavage, n = 85) and healthy controls (serum, n = 47). The distribution and association among airway and systemic TSLP, measures of AHR, type-2 inflammation, and severity of disease were assessed. Results: TSLP in sputum was associated with AHR independently of levels of eosinophils and fractional exhaled nitric oxide (ρ = 0.49, P = .005). Serum TSLP was higher in both eosinophil-high and eosinophil-low asthma compared to healthy controls: geometric mean: 1600 fg/mL (95% CI: 1468-1744 fg/mL) and 1294 fg/mL (95% CI: 1167-1435 fg/mL) versus 846 fg/mL (95% CI: 661-1082 fg/mL), but did not correlate with the level of AHR. Increasing age, male sex, and eosinophils in blood were associated with higher levels of TSLP in serum, whereas lung function, inhaled corticosteroid dose, and symptom score were not. Conclusions: The association between TSLP in sputum and AHR to mannitol irrespective of markers of type-2 inflammation further supports a role of TSLP in AHR that is partially independent of eosinophilic inflammation.
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| 9. |
- Beech, Augusta, et al.
(författare)
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Ers international congress 2022 : Highlights from the airway diseases assembly
- 2023
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Ingår i: ERJ open research. - 2312-0541. ; 9:3
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Tidskriftsartikel (refereegranskat)abstract
- The European Respiratory Society (ERS) celebrated the return of an in-person meeting in Barcelona, Spain, after 2 years of virtual congresses. The ERS Congress 2022 programme was replete with symposia, skills workshops and abstract presentations from all 14 assemblies, encompassing over 3000 abstracts presented in the form of thematic poster discussion and oral presentations. In this article, highlights from the ERS Congress 2022 (including from thematic poster sessions, oral presentations and symposia from keynote speakers), presented by Assembly 5 (Airway diseases, asthma, COPD and chronic cough), are reviewed by Early Career Members and experts in the field, with the aim of presenting key recent findings in the field.
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| 10. |
- Bergantini, Laura, et al.
(författare)
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ERS International Congress 2023 : highlights from the Airway Diseases Assembly
- 2024
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Ingår i: ERJ open research. - 2312-0541. ; 10:2
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Tidskriftsartikel (refereegranskat)abstract
- In this review, early career and senior members of Assembly 5 (Airway Diseases, Asthma, COPD and Chronic Cough) present key recent findings pertinent to airway diseases that were presented during the European Respiratory Society International Congress 2023 in Milan, Italy, with a particular focus on asthma, COPD, chronic cough and bronchiectasis. During the congress, an increased number of symposia, workshops and abstract presentations were organised. In total, 739 abstracts were submitted for Assembly 5 and the majority of these were presented by early career members. These data highlight the increased interest in this group of respiratory diseases.
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