We have standardized the PLGA-PEG based PS341 delivery to CF (Cftr-/-, FABP-CFTR gut corrected) murine lungs based on its ability to control Pa-LPS induced lung disease (Fig 8, 9, 10, 11 and 12) and inhibition of proteasomal activity (Fig 3). Here, CFTR is linked to cystic fibrosis.