Intravital microscopy of mucus transport in mice provides mechanistic insight into hypertonic saline treatment of Cystic Fibrosis

In clinical studies of cystic fibrosis (CF) patients, inhalation of 7% NaCl was found to be superior compared to 0.9%, which is attributed to increased hydration of mucus. However, mechanistic insight has been hampered by the inability to visualize mucus transport in vivo with microscopic resolution. To overcome this problem we developed a custom-built optical coherence microscope (OCM) providing a microscopic resolution. Images of mucus transport through the intact trachea were recorded in anesthetized spontaneously breathing wild type (WT) and βENaC-overexpressing mice as a model for CF. NaCl solution (30 µl,…