Formulations and methods are provided for improving the function, i.e. clinical outcome, of solid organ transplants. Lung transplantation is of particular interest. In the methods of the invention, a nanoparticle formulation comprising an effective dose of an iron chelator active agent in nanoparticle form, including without limitation, deferoxamine (DFO), deferasirox (DFX), and deferiprone (DFP), etc. is topically applied to the surface of tissues during episodes of graft rejection.