Patients with cystic fibrosis (CF) accumulate thick, sticky mucus in the lungs that clogs the airways and leads to life-threatening lung infections.
It has recently been proposed that differing concentrations of mucin with in mucus layers of the CF lung contribute to decreased mucus clearance; however, it has been challenging to accurately access mucin concentration.
In this issue of the Journal of Clinical Investigation, Mehmet Kesimer and colleagues at the University of North Carolina applied size exclusion chromatography/differential refractometry techniques to measure the mucin concentration in sputum from normal and CF airways.
Mucin concentrations and partial osmotic pressure were greater in CF secretions compared to normal secretions. Importantly, increased mucin concentration and partial osmotic pressure promoted mucus stasis, thereby contributing to lung infection and inflammation in CF.