Infection with Streptococcus pneumoniae triggers progression of pulmonary fibrosis by pneumolysin
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ABSTRACT: A two-hit model of adenoviral vector delivery of active transforming growth factor-β (TGFb) 1 to induce fibrosis in mice in conjunction with treatment of the mice with purified pneumolysin from Streptococcus pneumoniae was applied to characterize the role of this virulence factor on fibrosis perpetuation in mice The study was supported by a BMBF grant for the German Center for Lung Research, partner site BREATH (Biomedical Research in Endstage and Obstructive Lung Disease Hannover)
Project description:Idiopathic pulmonary fibrosis (IPF) is an irreversible diffuse parenchymal lung disease of poorly defined etiology. Patients with IPF frequently demonstrate distinctive lymphoplasmacellular infiltrations within remodeled lung tissue, the relevance of which in lung fibrogenesis is still understudied. Histopathological examination of explant lung tissue of patients with IPF revealed accentuated lymphoplasmacellular accumulates in close vicinity to or even infiltrating remodeled lung tissue. Similarly, we found significant accumulations of B cells interfused with T cells within remodeled lung tissue in two murine models of adenoviral TGF-β1 or bleomycin (BLM)-induced lung fibrosis. Such B cell accumulates coincided with significantly increased lung collagen deposition, lung histopathology and worsened lung function in WT mice. Importantly however, B cell deficient µMT KO mice responded similarly with lung tissue remodeling and worsened lung function upon either AdTGF-β1 or BLM treatment as did WT mice. Comparative transcriptomic profiling of sorted B cells collected from lungs of AdTGF-β1 and BLM exposed WT mice identified a large set of commonly regulated genes, however with significant enrichment observed for gene ontology terms (GO terms) apparently not related to lung fibrogenesis. Collectively, although we observed B cell accumulates in lungs of IPF patients as well as two experimental models of lung fibrosis, comparative profiling of characteristic features of lung fibrosis between WT and B cell-deficient mice did not support a major involvement of B cells in lung fibrogenesis in mice.
Project description:Lung tissue samples were collected from mice allowed to breath freely (FB) or on ventilation (LV) devices, either saline or acid treatment (four sample groups FB_saline; FB_acid; LV_saline; LV_acid)
Project description:Canine pyometra is a common inflammatory disease of the uterus in sexually mature bitches, caused by a secondary bacterial infection which leads to change in the plasma protein associated with the innate immune system. Proteomic offers a means to determine the profile of plasma in dogs with pyometra to provide important findings into general mechanisms operating during diverse inflammatory reactions. The plasma protein profile of healthy and pyometra affected bitches was determined by means of an isobaric tandem mass tag (TMT) label-based high-resolution quantitative proteomic approach. Six clinically healthy dogs (used as control group) and 6 dogs with pyometra were enrolled in the study. All dogs were admitted to the Small Animal Clinic, University of Veterinary Medicine Hannover and treated in accordance with the German Animal Welfare Law. The experimental design was approved by the Animal Welfare officer of the University of Veterinary Medicine and by the Ethic Committee of the responsible authority (Lower Saxony State Office for Consumer Protection and Food Safety, reference number 17A 101). Healthy dogs for blood collection were recruited by launching a call in the University of Veterinary Medicine Hannover network for students and staff members for haemostasis study, providing a free clinical and laboratory health check of their animal in combination with the blood collection. Residual sample material was used in the present study.
Project description:Cystic Fibrosis (CF) is the most common life limiting genetic disorder, characterized by chronic respiratory failure secondary to inflammation and chronic bacterial lung infection. Pseudomonas aeruginosa lung infection is associated with more severe lung disease and rapid progression of respiratory failure when compared to Staphylococcus aureus infection. We hypothesized that a specific signature of epigenetic factors targeting specific gene transcripts contributes to the increased morbidity seen in CF patients with chronic Pseudomonas infection. We collected exhaled breath condensate (EBC) from 27 subjects and evaluated miRNA signatures in these samples using commercial PCR array. We identified predicted mRNA targets and associated signaling pathways using Ingenuity Pathway Analysis. We found 11 differentially expressed miRNAs in EBC of patients infected with Pseudomonas aeruginosa compared to EBC from CF patients who were not chronically infected with Pseudomonas aeruginosa.
Project description:In order to elucidate the contribute of the pulmonary vasculature to lung fibrosis, we injured young and aged mice with bleomycine, to create a model of resolving versus persistent lung fibrosis. The animals were sacrificed 30 days after the injury (time point in which we observed a divergent resolving vs persistent lung fibrosis in young vs aged mice). We found that lung fibrosis resolution in young mice was accompained by the activation of transcriptional programs promoting vascular repair and lung fibrosis resolution. Lung endothelial cells from aged mice after injury failed to activate these programs, leading to dysrepair and progressive fibrosis.
Project description:The most preclinical used in vivo model to study lung fibrosis is the bleomycin-induced lung fibrosis model in 2-3-month-old mice. Although this model resembles key aspects of idiopathic pulmonary fibrosis (IPF), there are limitations in its predictability for the human disease. One of the main differences is the juvenile age of animals that are usually used in experiments, resembling humans of around 20 years. Because IPF patients are usually older than 60 years, aging appears to play an important role in the pathogenesis of lung fibrosis. We here compared young (3 months) and old (21 months) mice 21 days after intratracheal bleomycin instillation.
Project description:Coactivator associated arginine methyltransferase I (CARM1, also known as Protein aRginine MethylTransferase 4, or PRMT4) regulates gene expression by multiple mechanisms including methylation of histones and coactivation of steroid receptor transcription. Mice lacking CARM1 are smaller than their littermates, fail to breath, and die shortly after birth, demonstrating the critical role of CARM1 in development.We performed gene expression analysis to identify genes that are responsible for hyperproliferaion in CARM1 knockout lung. RNA extracted from murine lung at E18.5 with carm1 knockouts and wild type controls was hybridised to Affymetrix mouse430.2 GeneChips to identify differentially expressed genes in the disease state.
Project description:Pulmonary fibrosis (PF) is associated with many chronic lung diseases including Systemic sclerosis (SSc), Idiopathic Pulmonary Fibrosis (IPF) and Cystic Fibrosis (CF) which are characterized by the progressive accumulation of stromal cells and formation of scar tissue. Pulmonary fibrosis is a dysregulated response to alveolar injury which causes a progressive decline in lung function and refractory to current pharmacological therapies. Airway and alveolar epithelial cells and stromal cells contribute to pulmonary fibrosis but the cell-specific pathways and gene networks that are responsible for the pathophysiology are unknown. Recent animals models generated in our lab demonstrate clinical phenotypes seen in human fibrotic disease. The mouse model of transforming growth factor-? (TGF?)-induced fibrosis include conditionally expressing TGF? in the lung epithelium under control of the CCSP promoter driving rtTA expression (CCSP/TGF?). This allow the TGF? is only expressed in airway and alveolar epithelial cells and only when mice fed doxycycline (Dox). Similar to PF in humans, TGF? mice on Dox developed a progressive and extensive adventitial, interstitial and pleural fibrosis with a decline in lung mechanics. Thus, the TGF? transgenic mouse is a powerful model to determine lung cell-specific molecular signatures involved in pulmonary fibrosis. In this study, we sought to determine changes in the transcriptome during TGF?-induced pulmonary fibrosis. Our results showed that several pro-fibrotic genes increased in the lungs of TGF? mice. This study demonstrates that WT1 network gene changes associated with fibrosis and myfibroblast accumulation and thus may serve as a critical regulator fibrotic lung disease. mRNA profiles of CCSP/- and CCSP/TGFalpha mice treated with Dox
Project description:Supersulphides (inorganic and organic sulphides with sulphur catenation) manifest diverse physiological functions. These supersulphides are mainly generated from mitochondrial cysteinyl-tRNA synthetase (CARS2) that functions as a principal cysteine persulphide synthase (CPERS). Here we found powerful protective functions of supersulphides in viral airway infections (influenza and COVID-19) and chronic lung diseases, including chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and aged lungs. Enhanced supersulphide exhalation also occurred from human airways in COVID-19 as well as the hamster model of SARS-CoV-2 infection, as identified by breath supersulphur-omics that we developed herein. The lung damage related to oxidative stress and inflammation in mouse models of COPD, IPF, and ageing and the lethal effects that resulted were mitigated by endogenous supersulphides, supplied via CARS2/CPERS or exogenously by the supersulphide donor glutathione trisulphide. Our findings thus elucidated the airway protective role of supersulphides and their therapeutic potential in viral and chronic lung diseases.