A mechanistic insight into severe COPD: the nose as a surrogate for the airways

Abstract

A severe COPD signature in bronchial and nasal epithelial cells reflects reduced tissue repair and ECM regulation https://bit.ly/476S3PJ.

FIGURE 1

Overview of the study protocol. Bronchial brushings were obtained from patients with severe (n=123) and mild–moderate (n=23) COPD and 23 non-COPD control subjects and RNA sequencing performed. After identifying a set of differentially expressed genes between severe COPD and non-COPD subjects, genes within the dataset relating to mild–moderate COPD, specific cell subtypes and inhaled corticosteroid (ICS) use were removed to give a 219 gene severe COPD bronchial epithelial cell signature. Key down-regulated genes included fibronectin-1 (FN1) and vascular endothelial growth factor α (VEGFA) which were linked to suppression of extracellular matrix (ECM)- and tissue repair-associated pathways. The reduced expression of these genes and pathways were replicated in paired nasal bronchial brushings and in nasal epithelial cells from a separate cohort of severe COPD patients and non-COPD controls. mCOPD: moderate COPD.