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Objective To create a method for constructing a tissue-engineered graft with self-derived bone marrow cells and heterogeneous acellular matrix. Methods The mononuclear cells were isolated from bone marrows drawn from piglets and cultured in different mediums including either vascular endothelial growth factor (VEGF) or platelet derived growth factor BB (PDGF-BB) to observe their expansion and differentiation. The aortas harvested from canines were processed by a multi-step decellularizing technique to erase. The bone marrow mononuclear cells cultured in the mediums without any growth factors were seeded to the acellular matrix. The cells-seeded grafts were incubated in vitro for 6 d and then implanted to the cells-donated piglets to substitute parts of their native pulmonary arteries. Results After 4 d culturing, the cells incubated in the medium including VEGF showed morphological feature of endothelial cells (ECs) and were positive to ECs-specific monoclonal antibodies of CD31, FLK-1, VE-Cadherin and vWF. The cells incubated in the medium including PDGF-BB showed morphological feature of smooth muscle cells (SMCs) and were positive to SMCs-specific monoclonal antibodies of α-SMA and Calponin. One hundred days after implantation of seeded grafts, the inner surfaces of explants were smooth without thrombosis, calcification and aneurysm. Under the microscopy, plenty of growing cells could be seen and elastic and collagen fibers were abundant. Conclusion Mesenchymal stem cells might exist in mononuclear cells isolated from bone marrow. They would differentiate into endothelial cells or smooth muscle cells in proper in vitro or in vivo environments. The bone marrow mononuclear cells might be a choice of seeding cells in constructing tissue-engineered graft.