The primary objective of the study is the evaluation of the effect of hemodiafiltration during ex vivo lung perfusion in marginal donor lungs, and its feasibility. The hypothesis of this study is that this therapy could stabilize perfusate electrolyte composition, remove toxins and waste products, normalize pH levels and prevent edema formation, thereby reconditioning marginal donor lungs for transplantation. The proposed pilot study addresses the unmet clinical needs in several aspects: a) for the first time a homeostatic device will be introduced in EVLP to reach stable perfusate composition; b) the proposed modification of the standard EVLP could lead to longer perfusion times, making elective transplantation possible and setting the base for possible ex vivo lung treatments; c) the ultimate effect of the proposed study is to increase organ availability through reconditioning of marginal donor lungs.