Lung transplantation is the last therapeutic option for end-stage pulmonary failure. Yet, clinical complications may rise after transplantation, such as primary grafts dysfunction (PGD) or chronic lung allograft dysfunction (CLAD). Current clinical parameters have failed to assess the quality of the graft and to predict transplantation outcome. Extracorporeal photopheresis (ECP) is a treatment for graft-versus-host disease. Peripheral blood white blood cells (WBC) are isolated, exposed to 8-methoxypsoralen photosensitizing agent, and subsequently treated with ultraviolet radiation before reinfusion into the patient, causing massive WBC apoptosis. Our working hypothesis is that extracellular vesicles (EV) produced by either the pre-transplantation organ (donor) or host (recipient) could be non-invasive biomarkers to evaluate tissue damage at the cellular level and to monitor organ engraftment
