The airway diseases asthma and COPD affect millions of individuals worldwide.¹ These diseases are major determinants of chronic morbidity and mortality, and represent a substantial public health burden.^2–4 Despite differences in etiology, clinical characteristics, and pathophysiology, both conditions share important features, such as airway obstruction and chronic airway inflammation. As a result of modern lifestyle, the incidence of both diseases is steadily increasing worldwide and effective preventive and treatment strategies are unmet needs.⁵