| Marrow stromal cells are characterized by their abilities of self-renewal and multipotent differentiation into various lineages of tissue cells. For decades, intensive attentions have been paid to hematopoietic stem cells of bone marrow that have been achieved great progreses. Marrow stromal cells were thought to play a main role in nutriment and support of hematopoietic growth, proliferation and differentiation, regarded as the second place in marrow. But in recent years, the concept of Marrow stromal cells has been dramatically widened by the demonstration of their plasticities. For instance, Marrow stromal cells can reconstitute myocadium and vasculogenesis. Moreover, the special population of non-hematopietic stromal cells in bone marrow is identified as the progenitors of mesoderm-derived tissue cells. These undifferentiated bone marrow stromal cells originated from embryonic mesoderm have been successfully cultured in vitro. It is confirmed that these cells can be induced to terminally differentiate into at least seven types of cells-osteoblasts, chondrocytes, myocardial cells, smooth muscle cell, endothelial cells, neurons, and astrocytes, under proper culture condition, such as in the presence of the endothelial cell growth supplement as well as chemical substances. Therefor this compartment of cells is currently referred to bone marrow mesenchymal stem cells(MSCs).Cell therapy can be considered as a strategy aimed at replaceing, repairing or enhancing the biological function of a damaged tissue, organ or system by means of autologous or allogeneic cells. Many aged people are suffering from degenerative diseases, such as coronary arteriosclerotic cardiopathy and Alzheimer's Disease of which the optimal clinnic treatment have not achieved up to date. If possible, cell therapy may be a better way to cure these kinds of diseases. Tissue injuries and malfunction often occur when the blood vessels sclerosis causes the tissue ischemia and hypoxia, as shown in people who are suffering from artery sclerosis and having advanced age, hypertension, hyperlipidemia, diabetes or endothelial dysfunction. The current tissue ischemic treatment, such as pharmaceutical therapy, PCI, CABG and genetic therapy, have not gained content effects on some thosepatients because of limitations imposed by a less-responsive endothelial cell substrate. Some researchers have found that MSCs infused in coronary artery also take part in the repair of ischemic myocardium. Because of their ability of incorperation into injuried tissues, MSCs can be used as the target of in vivo gene therapy, which may be a common therapy method to cardiovascular diseases.The pluripotent MSCs have been shown to be present in adult marrow, in quantities sufficient to permit their use as a "supply-side" strategy for therapeutic neovascularization. Therefore we inferred that MSCs might be isolated from marrow in quantities sufficient to permit their harvest, and, after ex vivo expansion, be administered systemically for the purpose of enhancing neovascularization. Indeed, the experiments performed to test this hypothesis have disclosed that neovascularization of the ischemic hindlimb is augmented.Metheds: Bone marrow mononuclear cells of BALB/C mice were separated by gradient centrifugation with a Percoll(density 1.082g/cm3), and cultured in DMEM/F12 medium containing 10%FBS, penicillin(100U/ml), streptomycin(100U/ml) at 37℃ in a humidified environment with 5% CO2. The hematopoietic cells and nonadherent cells were removed by change medium 24 hours after planting. The growth curve, adhesive rate, cleavage index, cell cycle, ultrastructure and vasculogenesis of passed cells were investigated. To demonstrate if the cultured MSCs possess the abilities of special differentiation, special formula media complement, endothelial cell growth supplement(M199 medium, 50ng/ml vascular endothelial growth factor, 5ng/ml basic fibroblast growth factor, 2ng/ml insulin-like growth factor-1,10U/ml heparin), were used to induce MSCs to differentiate toward e...
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