Project description:Hypoxia is a common microenvironmental condition in the mucus-obstructed, infected, and inflamed airways of lung disease patients and is known to influence immune responses in the lungs. However, the effects of hypoxia on lung host defence against respiratory bacterial infections relevant to chronic pulmonary disease are less understood. Nontypeable Haemophilus influenzae (NTHi), an opportunistic respiratory pathogen, frequently colonizes the lower airways of patients with chronic lung diseases and is associated with poor clinical outcomes. Human ex vivo lung explants were infected with a clinical strain of NTHi under normoxic and hypoxic conditions for 24 hours. The host response to infection and the effect of hypoxia were investigated using RNA sequencing.
Project description:Distal airway stem cell (DASC) expressing basal cell restrictive transcription factor p63 and keratin-5 (Krt5) has a strong ability of regeneration after lung injury. Such cells are originated from primitive progenitors in distal airways and could expand/migrate to inflamed damaged lung parenchymal region to form ‘KRT5 pods’ once activated by various types of tissue injury. We isolated the mouse DASC and transplanted the GFP-labelled mDASC into the bleomycin-injured mouse lung by intratracheal instillation. Mice were sacrificed at 30 and 90 days post transplantation and their lung tissue were harvest to detect GFP signal by fluorescence stereomicroscope, the region of which was dissect for single cell-RNA-seq (scRNA-seq). We utilized scRNA-seq to trace the fate of transplanted mDASCs at 30 days and 90 days post transplantation, which revealed cell types differentiated from the transplanted DASCs.
Project description:The field of graft preservation has made considerable strides in recent years improving outcomes related to solid organ restoration and regeneration. In lungs, the use of ex vivo lung perfusion (EVLP) in line with devices and treatments has shown promising results within preclinical and clinical studies with the potential to improve graft quality. The benefit of the therapy would be to render marginal and declined donor lungs suitable for transplantation, ultimately increasing the donor pool available for transplantation. Additionally, such therapies used in machine perfusion could also increase preservation time, facilitating logistical planning. Cytokine adsorption has been demonstrated as a potentially safe and effective therapy when applied to the EVLP circuit and post transplantation. The mechanism by which this treatment improves the donor lung on a molecular basis is not yet fully elucidated. We hypothesized that there were characteristic inflammatory and immunomodulatory differences between lungs treated with and without cytokine adsorption, reflecting in proteomic changes in gene ontology pathways and across inflammation-related proteins. In the current study we investigate the molecular mechanisms and signaling pathways of how cytokine adsorption impacts the lung function when used during EVLP and when used post transplantation as hemoperfusion in a porcine model. Lung tissue from EVLP and post lung transplantation were analyzed for their proteomic profile using mass spectrometry. The inflammatory and immune processes were compared between the treated and the non-treated groups to show the differences occurring between the forms of graft preservation.
Project description:In utero exposure to arsenic via drinking water increases the risk of lower respiratory tract infections during infancy and mortality from bronchiectasis in adulthood. Pregnant mice were exposed to arsenic, and gene expression patterns were profiled in peripheral lung tissue obtained from the offspring at 2 weeks of age. Pregnant Mice (BALB/c, C57BL/6, C3H/HeARC) mice were exposed to arsenic (or control) via drinking water from day 8 of gestation until the birth of their offspring. After giving birth, mothers were given control drinking water. At 2 weeks post-natal age, total RNA was extracted from peripheral lung tissue of the offspring and analysed on Affymetrix microarrays.
