It has been established that optimizing cell seeding onto tissue engineering vascular grafts (TEVG) is associated with reduced inflammatory responses and reduced post-operative stenosis of TEVG. Cell seeding increased TEVG patency in a dose dependent manner, and TEVG patency improved when more cells were seeded, however duration of incubation time showed minimal effect on TEVG patency. Methods of engineering patient specific TEVG including optimal numbers of cells to maintain graft patency and reduce post-operative stenosis are provided. Closed, single-use customizable systems for seeding TEVG are also provided. Preferably the systems are custom-designed based on morphology of the patient specific graft, to enhance the efficacy of cell seeding.