High expression of high-mobility group box 1 in the blood and lungs is associated with the development of chronic obstructive pulmonary disease in smokers

Background and objective High‐mobility group box 1 (HMGB1) is an important mediator in multiple pathological conditions, but the expression of HMGB1 in chronic obstructive pulmonary disease (COPD) has not yet been completely investigated. We aimed to analyze the relationship between HMGB1 expression in blood and lung tissue and the development of COPD. Methods Twenty‐eight patients admitted for single pulmonary surgical intervention were enrolled. The expression of HMGB1 in blood and lung tissue was evaluated by enzyme‐linked immunosorbent assay analysis and immunohistochemistry stain, respectively. The study patients were divided into smokers with COPD (n = 11), smokers without COPD (n = 8) and non‐smoker healthy controls (n = 9). Results Smokers with COPD compared with smokers without COPD and healthy controls were older in age, with lower post‐bronchodilator forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) ratio (63.1 ± 5.5 vs 77.6 ± 3.6 and 84.5 ± 5.8, P