S100A12 and chronic obstructive pulmonary disease: This is at variance with the results of three recent studies showing that: (a) CML is detected in the epithelial lining fluid from peripheral airways in patients with COPD, and correlates with the severity of airflow obstruction [36]; (b) S100A12 concentration in the sputum of patients with COPD is significantly higher than in healthy subjects [37]; (c) HMGB1 levels in induced sputum are significantly higher in asthmatic patients than in controls, and correlate significantly with the severity of asthma and the percent of neutrophils in sputum [38].