In cystic fibrosis, ion-transport abnormalities cause problems in many organs. A small molecule that forms cell-membrane pores allowing ion transport shows therapeutic promise in human cells and a model of the disease.
In cystic fibrosis, abnormalities in the ion-channel protein CFTR cause problems in the transport of chloride (Cl−) and bicarbonate (HCO3−) ions in the epithelial cells that line the airways of lungs, resulting in a build-up of mucus in these airways. This hinders the normal process that removes mucus and the inhaled bacteria trapped in it, and the resulting airway blockage leads to persistent infections and inflammation, which destroy lung tissue1. Writing in Nature, Muraglia et al.2 demonstrate that a small molecule called amphotericin B, which can form an ion channel in the cellular membrane of airway cells, restores ion transport and antibacterial defences when tested in vitro in human cells from people with cystic fibrosis and in an in vivo animal model of the disease.