| Adult Bone Marrow Stem Cells (ABMSC) are normally present in adult bone marrow, pluripotent cells, and can differentiate into a variety of cell types, including cells in bone, muscle, fat, tendon, cartilage, or cardiomyocytes, and can be ideal resources of transplantation therapy. Facultative progenitor cells like oval cells (OC) exist in the liver and can be induced to proliferate following hepatic injury, when growth of mature hepatocytes is suppressed. However, the nature, origin and role of OC and other putative liver cell progenitors in liver development and repair remain unclear.For many years , OC were believed to originate from cells present in the canals of Herring or from blast-like cells located near the bile duct. Recently, results of cross-sex and cross-strain bone marrow (BM) and whole liver transplantation experiments indicated that BM might be a source of hepatocyte progenitors. Further evidence confirmed for the existence of hepatocyte stem cells in the BM (named as Bone marrow Derived Hepatocyte Stem Cells,BDHSC), they can express albumin, AFP and c-Met. OC and hematopoietic stem cells share common cell surface receptors and antigens, including hematopoietic stem cell markers CD34, Thy-1, c-Kit, Flt-3 and all known oval cell antigens.The ability to identify and exploit a human hepatic clonal stem cell could have important clinical implications, as generating large numbers of differentiated and therefore fully functional human hepatocytes have enormous pontential. Primary hepatocytes remain the ultimate choice for use in bioartificial liver support devices. Other important areas where progress has been limited due to lack of sufficient numbers of good quality primary human hepatocytes include hepatocyte transplantation for the treatment of metabolic disorders or fulminate liver failure, and evaluation of drug toxicology and pharmacokinetics so vital today for the development of safe new therapeutic drugs.Many growth factors and cytokines, most notably HGF, transforming growth factor-a, interleukin-6, tumor necrosis factor-a, and insulin appear to play important roles in liver regeneration. In experimented models, hepatocyte proliferation is suppressed by exposure to the 2-acetylaminofluorene (2-AAF) and hepatic injury can be induced by partial hepatectomy. The model was usually used to induce OC proliferation, and Peterson has successfully induced differentiation of bone marrow cells into OC in the models. It is unclear whether it is possible to induce differentiation of bone marrow cells into OC in vitro.Hepatocytes may synthesize and secret albumin. Albumin was usually used as a marker to detect hepatocyte lineage in bone marrow cells. However, Borregaard N and Handagams N have found that neutrophils and megakaryocytes have albumin in cytoplasmic "granules", while mRNA for albumin can not be detected in those cells. It is necessary to decide whether Albumin may regard as a marker to detect hepatocyte lineage in bone marrow cells and bone marrow mono-nucleate transformation cells in culture.In this study, the aim is to examine cytological effects of the serum of liver lesion model rat, HGF, IL-6 and TNF-a on adult bone marrow cells in culture, to find factors to influence transformation of bone marrow stem cells, and to discuss the possibility of obtaining hepatocyte in vitro. Moreover, it will be decided whether it is appropriate to detect hepatocyte lineage in bone marrow cells and bone marrow mono-nucleate transformation cells in culture by the methods of immunology with albumin marker.BMMNC were collected from the femora of male SD rats (2-months-old or more). BMMNC were precultured in the MDM/F12 long term culture system (LTCS) (Including: IMDM 38%, F12 38%, FBS 20%, Hepes 10'2mol/L, 2-ME 2x10-5mol/L, Hydrocortisone 5x10-7mol/L, L-glutamine 0.3g/L, Iselin 0.4u/L, Penicillin 10u/L, Streptomycin 5x10-4Vg/L, and so on) at a cell density of Ixl07/cm2. Medium was changed every 3 days. After 5 days, the cells in the logarithmic phase of growth that had beenpassaged...
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