Analysis of microRNA expression by nasal epithelial cells to predict which patients with COPD are likely to experience frequent exacerbations

Chronic obstructive pulmonary disease (COPD) is a disabling respiratory condition which affects approximately 7.5% of Australians over the age of 40. Acute exacerbations ("flare-ups") of COPD, often triggered by bacterial or viral infections, frequently lead to presentation to emergency departments and/or to admission to hospital. It is now clear that a sub-population of COPD patients is more likely to develop recurrent exacerbations. These "frequent exacerbators" account for approximately 15% of all COPD patients, but for over 50% of all exacerbation-related hospitalisations. Consideration is now being given to the potential benefits of identifying sub-populations of COPD patients to reduce exacerbations, by administration of targeted therapy. However, there are no diagnostic criteria or reliable biomarkers that allow early identification of these patients. Airway epithelial cells (AEC) are key drivers of inflammation in COPD and produce a variety of regulatory mediators including microRNAs. We hypothesise that patients who are frequent exacerbators will exhibit a characteristic profile of expression of microRNA by nasal AEC. In this project, we will analsyse the expression of microRNA by nasal AEC from patients with stable COPD, as well as COPD patients classified as frequent exacerbators. We aim to identify a profile of expression which is characteristic of frequent exacerbators who be likely to benefit from early targeted therapy. If successful, this could reduce the risk of exacerbations of COPD, as well as the associated morbidity and health care costs.