In addition to describing the main known function of the CFTR protein as a Cl− channel, this review focusses on the relationships between the CFTR protein and the transport of HCO3−, glutathione (GSH), and thiocyanate (SCN−), as well as the immune cells and the metabolism of lipids that influence MCC and innate immunity and lead to chronic infection and inflammation, all of which are considered as key characteristics in the pathophysiology of CF. Here, CFTR is linked to cystic fibrosis.