BPIFA1 and respiratory system disorder: In this review, we shall describe the pros and cons of several different biological-based therapies for respiratory disease, including dornase alfa, a recombinant DNAase that reduces mucus viscosity and short palate lung and nasal epithelial clone 1 (SPLUNC1)-derived peptides that treat Na+ hyperabsorption and rebalance CF airway surface liquid homeostasis.