Background Acute exacerbations of chronic inflammatory lung diseases, such as chronic obstructive pulmonary disease (COPD), are frequently associated with rhinovirus (RV) infections. Despite these... Show moreBackground Acute exacerbations of chronic inflammatory lung diseases, such as chronic obstructive pulmonary disease (COPD), are frequently associated with rhinovirus (RV) infections. Despite these associations, the pathogenesis of virus-induced exacerbations is incompletely understood. We aimed to investigate effects of cigarette smoke (CS), a primary risk factor for COPD, on RV infection in airway epithelium and identify novel mechanisms related to these effects. Methods Primary bronchial epithelial cells (PBEC) from COPD patients and controls were differentiated by culture at the air-liquid interface (ALI) and exposed to CS and RV-A16. Bulk RNA sequencing was performed using samples collected at 6 and 24 h post infection (hpi), and viral load, mediator and l-lactate levels were measured at 6, 24 and 48hpi. To further delineate the effect of CS on RV-A16 infection, we performed growth differentiation factor 15 (GDF15) knockdown, l-lactate and interferon pre-treatment in ALI-PBEC. We performed deconvolution analysis to predict changes in the cell composition of ALI-PBEC after the various exposures. Finally, we compared transcriptional responses of ALI-PBEC to those in nasal epithelium after human RV-A16 challenge. Results CS exposure impaired antiviral responses at 6hpi and increased viral replication at 24 and 48hpi in ALI-PBEC. At 24hpi, CS exposure enhanced expression of RV-A16-induced epithelial interferons, inflammation-related genes and CXCL8. CS exposure increased expression of oxidative stress-related genes, of GDF15, and decreased mitochondrial membrane potential. GDF15 knockdown experiments suggested involvement of this pathway in the CS-induced increase in viral replication. Expression of glycolysis-related genes and l-lactate production were increased by CS exposure, and was demonstrated to contribute to higher viral replication. No major differences were demonstrated between COPD and non-COPD-derived cultures. However, cellular deconvolution analysis predicted higher secretory cells in COPD-derived cultures at baseline. Conclusion Altogether, our findings demonstrate that CS exposure leads to higher viral infection in human bronchial epithelium by altering not only interferon responses, but likely also through a switch to glycolysis, and via GDF15related pathways. Show less
Vitamin D plays an active role in the modulation of innate and adaptive immune responses as well as in the protection against respiratory pathogens, e.g. by increasing expression of the... Show moreVitamin D plays an active role in the modulation of innate and adaptive immune responses as well as in the protection against respiratory pathogens, e.g. by increasing expression of the antimicrobial peptide hCAP18/LL-37. The main aim of this thesis was to elucidate the role of inflammation on the protective effects of vitamin D on respiratory host defense responses in chronic inflammatory lung diseases such as chronic obstructive pulmonary disease (COPD). Airway epithelial host defense responses in COPD patients are defective and these patients are therefore more susceptible to respiratory infections. In this thesis we have shown that exposure to cigarette smoke, a main risk factor for COPD, reduced expression of certain host defense mediators by affecting end-stage airway epithelial differentiation and might explains why COPD patients are more susceptible to respiratory infections. We have further demonstrated in the studies presented in this thesis that certain airway inflammatory mediators could possibly interfere with vitamin D metabolism by promoting expression of vitamin D degrading enzyme CYP24A1, thereby reducing local levels of vitamin D and accompanying protective antimicrobial and anti-inflammatory actions. These new insights may yield possible new strategies to target CYP24A1 that enhance local levels and signaling of vitamin D to increase protection against exacerbations in COPD patients. Show less
Considering the worldwide ageing of populations, there is a growing need for rehabilitation programmes specifically designed for geriatric patients. The authors developed and implemented a post... Show moreConsidering the worldwide ageing of populations, there is a growing need for rehabilitation programmes specifically designed for geriatric patients. The authors developed and implemented a post-acute geriatric rehabilitation programme in a skilled nursing facility for patients with advanced chronic obstructive pulmonary disease(COPD)- the GR-COPD programme. This paper describes the characteristics of the programme and presents three case studies to illustrate its possible benefits for individual patients. The case studies show that integration of rehabilitation and palliative care components is essential, as patients with advanced COPD admitted to hospital for an acute exacerbation often suffer from high symptom burden, deteriorating quality of life, and poor prognosis. Development and implementation of a post-acute GR-COPD programme is feasible and can offer substantial benefits for patients with advanced COPD admitted to hospital for an acute exacerbation. Show less
