Tissue-engineered veins were generated by reconditioning decellularized veins from both human and pig with whole-blood from respective species. Decellularized human vena femoralis from three donor were reconditioned with human whole blood from four donors. In addition, decellularized pig vena cava from three donors were reconditioned with pig whole blood from three different donors. The proteomes of the tissue-engineered veins were investigated applying the TMT-based proteomics to explore differences between species, regarding the gain of biological material by the reconditioning process.