| Currently, Bone tissue defect due to trauma , post-operation of tumor , periodontal disease and congenital malformation, often leads to loss of bone tissue and masticatory function and influences facial appearance, which will bring about physical and mental distress patients . To meet the need of restoration, a great many of scientists have tried many methods to restore the bone defection, and experienced many stages, including autograft, allotransplantation , heterogentic transplantation , the substitute of artificial bone and organized artificial bone and so on . But those methods also exist some shortcomings such as secondary damage, reject reaction , poor moulding and so on . With the development of cell biology, molecular biology, materials science , tissue engineering has got unprecedent developing. Many experiments and studies have confirmed that tissue engineering artificial bone is a potential technique to restore bone defection and should be the targeted direction for later study. However, this method also have many deficiencies, for example , small area of repairation, poor durability and integration of artificial bone, etc. Recently investigations have proved that the process of bone repairation includes three basic aspects, that is revascularization, bone regeneration and confluence of extremities. Revascularization as the most fundamental one, can not only transfer precursor osteoblasts, associated signal molecular, necessary nutrients and other necessary cells associated with tissue repair to the local microenvironment, but also remove metabolic products and necrotic debris. So building the vascular system earlier is the critical step for stock of the implant, confluence of extremities and function recovery.To solve this problem, according to Frerich's suggestion that vascular endothelial cell may be used as the seed cells of organized vascular, and different kinds of cells co-culture is possible, we applied artificial vascular to construct vascularized artificial bone, and try to find the effect and significance of osteoblasts and endothelial cells interaction in vascularization, bone formation and restoration of bone defect . The aim of this study is to testify osteoblasts and endothelial cells can be the base of vascularized establishment and regeneration of bone tissue, and increase blood supply of artificial bone ,so as to promote earlier repair of the bone defect, and open up the domain of artificial bone for large area of bone defect restoration and treatment.Mesenchymal stem cells and vascular endothelial cells were extracted from three-month Wistar rat , and the cells were cultured and generated in vitro. Mesenchymal stem cells possessed the activity of osteblast tested by Alkaline phosphatase staining and Von-kossa staining ; cells extracted from renal cortex were Vascular Endothelial Cells proved by CD34 immunohistochemical staining and electron microscope.The third generation of Mesenchymal stem cells and vascular endothelial cells, and several PLGA scold material 1×1×0.5cm that are dealed, were used to construct the three-dimensional Contact co-culture, co-culture with indirect and alone culture system models. After 5days,we receive the culture medium, and detect the activity of the osteocalcin by the osteocalcin analytical reagent kit. We digest and collect the cells, and detect the quantity of protein and of Alkaline phosphatase. By the statistics analysis , the osteogenetic ability of bone marrow mesenchymal stem cells co-cultured was higher than that of simple cultured(P<0.05), and the osteogenetic ability of direct co-cultured cells was higher than that of indirect co-cultured(P<0.05).We get the conclusion that The osteogenetic ability of bone marrow mesenchymal stem cells can be regulated by cytokines and cell membrane proteins when co-cultured with endothelial cells.Mesenchymal stem cells and vascular endothelial cells that are culture three generation are seeded on the PLGA scold material that are dealed, to construc...
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