CFTR and cystic fibrosis: These are all altered in CF and related to choline metabolism: via HCO3−, requiring CFTR-mediated Cl− transport for the Cl−/HCO3− antiporter, CFTR is crucial for physiological pH regulation in the small intestine, mucin solubilization, and the optimal function of pancreatic phospholipase A2 IB (sPLA2IB).