Increased human Ca2+-activated Cl- channel 1 expression and mucus overproduction in airway epithelia of smokers and chronic obstructive pulmonary disease patients

Background The mechanisms underlying the association between smoking and mucus overproduction remain unknown. Because of its involvement in other airway diseases, such as asthma, we hypothesized that Ca2+-activated Cl- channel 1 (CLCA1) was associated with overproduction of mucus in the airways of smokers and COPD patients.