A Controlled Study of Adenoviral-Vector–Mediated Gene Transfer in the Nasal Epithelium of Patients with Cystic Fibrosis

Cystic fibrosis is a recessive genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator ( CFTR ) gene. 1 – 4 The normal CFTR gene codes for a protein (CFTR) that plays a key part in epithelial transport of salt and water. 5 , 6 Mutations in CFTR result in abnormal secretions that obstruct and ultimately damage epithelium in many areas of the body. 7 The principal cause of death among patients with cystic fibrosis is lung disease. Patients who are homozygous for mutations in the CFTR gene have defective cyclic AMP (cAMP)–regulated secretion of chloride 8 , 9 and elevated absorption of sodium . . .