Genetically engineered (GE) porcine kidney xenografts have been used recently in pig-to-human brain-dead decedent xenotransplantation. However, immunofluorescence (IF) and electron microscopy (EM) findings of xenografts have not been fully described. Here we report novel IF and EM features of GE pigs with ten genetic modifications(10GE) xenografts with clinical correlation in three cases of pig-to-human brain-dead decedent xenotransplantation, performed at our institution. Preimplant biopsies unexpectedly demonstrated clinically silent mesangial immune complex deposits in all three xenografts indicating porcine donor–related process.