Given the tight binding of FUD to the assembly site for FN and the improved pharmacokinetic properties of PEG-FUD in vivo, in this study, we sought to investigate the ability of PEG-FUD to target FN deposition in human IPF tissues ex vivo and during the early time points after bleomycin-induced murine pulmonary injury in vivo (46, 47). The gene discussed is FN1; the disease is idiopathic pulmonary fibrosis.