Airways inflammation and treatment during acute exacerbations of COPD

Erik Bathoorn¹, Huib Kerstjens¹, Dirkje Postma¹, Wim Timens², William MacNee³

¹Groningen Research Institute for Asthma and COPD (GRIAC), Department of Pulmonology, ²Department of Pathology, University Medical Center Groningen, University of Groningen, the Netherlands; ³Edinburgh Lung and the Environment Group Initiative/Colt Research Laboratories, Medical School, University of Edinburgh, Edinburgh, Scotland, United Kingdom

Introduction: Inflammation is a core feature of acute chronic obstructive pulmonary disease (COPD) exacerbations. It is important to focus on inflammation since it gives insight into the pathological changes causing an exacerbation, thereby possibly providing directions for future therapies which modify inflammation.

Objectives: To provide a cell-by-cell overview of the inflammatory processes during COPD exacerbations. To evaluate cell activation, and cytokine production, cellular interactions, damaging effects of inflammatory mediators to tissue, and the relation to symptoms at the onset of COPD exacerbations. To speculate on future therapeutic options to modify inflammation during COPD exacerbations.

Results: During COPD exacerbations, there is increased airway wall inflammation, with pathophysiological influx of eosinophils, neutrophils, and lymphocytes. Although links have been suggested between the increase in eosinophils and lymphocytes and a viral etiology of the exacerbation, and between the increase in neutrophils and a bacterial aetiology, these increases in both inflammatory cell types are not limited to the respective aetiologies and the underlying mechanisms remain elusive.

Conclusion: Further research is required to fully understand the inflammatory mechanisms in the onset and development of COPD exacerbations. This might make inflammatory pathway-specific intervention possible, resulting in a more effective treatment of COPD exacerbations with fewer side effects.

Keywords: COPD, exacerbation, inflammation, therapy