CFTR and cystic fibrosis: Macrophage immune dysfunction in CF is well established (3, 4, 57), but the extent of this dysfunction remains unclear, as well as the fundamental mechanisms that produce this phenotype and what the relative contribution is of secondary acquired factors (exposure of the cells to systemic inflammation and a chronically inflamed/infected lung) and primary, intrinsic (loss of functional CFTR in myeloid cells) causal factors.