In mouse models of acute and chronic Pseudomonas aeruginosa lung infection, aerosol administration of bovine Lf (bLf) significantly reduced inflammation and improved mouse health. Preliminary results in CFTR KO mice seem to confirm the beneficial role of bLf already demonstrated in wild-type mice and suggest significant antibacterial activity. The formulation of bLf-loaded nanoparticles (bLf NANO) to be aerosolized was optimised. In particular, the stability of bLf NANOs was shown. This study should represent the basis for future clinical trial(s) and for involving possible industrial partner(s).