To determine if BPIFA1 and BPIFB1 have an anti-inflammatory effect on airway epithelial cells during infection, three different CF airway epithelial cell lines were pretreated with recombinant BPIFA1 or BPIFB1 prior to stimulation with P. aeruginosa. Pre-treatment of IB3-1 and CuFi-1 with recombinant BPIFA1 prior to stimulation with PAO1 resulted in a reduction in IL-8 production (P = 0.002 and 0.003, respectively)(Fig 5). Here, BPIFB1 is linked to cystic fibrosis.