Imaging viscosity of intragranular mucin matrix in cystic fibrosis cells

Abnormalities of mucus viscosity play a critical role in the pathogenesis of several respiratory diseases, including cystic fibrosis. Currently, there are no approaches to assess the rheological properties of mucin granule matrices in live cells. This is the first example of the use of a molecular rotor, a BODIPY dye, to quantitatively visualize the viscosity of intragranular mucin matrices in a large population of individual granules in differentiated primary bronchial epithelial cells using fluorescence lifetime imaging microscopy.