Expression of cell surface antigens during the differentiation of osteoblast by human bone marrow-derived mesenchymal stem cells / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the phenotypic changes of some cell surface antigens in the process that the bone marrow-derived mesenchymal stem cells (MSCs) differentiate into osteoblast lineage under certain conditions.</p><p><b>METHODS</b>The mononuclear cells were isolated from human bone marrow and cultured in the medium in the presence (experimental group) or absence (control group 1) of dexamethasone, ascorbic acid and beta-glycerophosphate, or in the alpha-MEM only (control group 2). The expressions of CD45, CD34, CD117, CD90, and HLA-DR were examined by flow cytometry on culture day 7, 12, and 17.</p><p><b>RESULTS</b>Human bone marrow MSCs can differentiate into mature cells with the characteristics of osteoblasts in vitro. The expression of CD45 was low in the experimental group and in the control groups on culture day 7, and became negative from day 12 in all groups. The expressions of CD34 and CD117 were negative at all time points. The expression of CD90 increased on day 12 in all groups, and was more obvious in the control groups. The expression of HLA-DR was gradually elevated along with the differentiation and maturation of osteoblasts in the experimental group, but dropped in the control groups in the later time points.</p><p><b>CONCLUSIONS</b>MSCs can differentiate into mature osteoblasts after induction. The expression of cell surface antigens during differentiation has characteristic changes, which may be key markers in the early stage of osteoblasts differentiation.</p>

Study of cryopreservation of differentiated hepatocyte derived from human bone marrow stem cells / 中华外科杂志

<p><b>OBJECTIVE</b>To observe the viability and function of human bone marrow stem cell-derived hepatocytes following cryopreservation in vitro.</p><p><b>METHODS</b>Human bone marrow cells were induced to differentiate into hepatocytes in the presence of multiple factors. Mature hepatocytes were cryopreserved in 90% FBS and 10% DMSO (Group A), 10% FBS, 30% glycerol and 60% conditioned medium (Group B), and 10% FBS, 10% DMSO, and 80% UW solution (Group C). The cells were thawed after 4 weeks, and the cell viability and the albumin level were determined.</p><p><b>RESULTS</b>The human bone marrow derived hepatocytes maintained functional morphology after thawing. The viabilities in Group A, B and C were (60.0 +/- 3.3)%, (91.0 +/- 2.6)%, and (89.0 +/- 1.4)%, respectively. After culturing for 24 h, the albumin levels in Group A, B and C were (0.210 +/- 0.005) g/L, (0.340 +/- 0.020) g/L and (0.330 +/- 0.030) g/L, respectively.</p><p><b>CONCLUSIONS</b>Human bone marrow stem cell-derived hepatocytes can maintain the viability and function after cryopreservation. These cells may contribute to an important source of hepatocytes for clinical hepatocyte transplantation and artificial liver support system.</p>

Expression of albumin during hepatocyte differentiation by human bone marrow stem cells / 中华外科杂志

<p><b>OBJECTIVE</b>To observe the expression pattern of albumin during the hepatocyte differentiation by human bone marrow stem cells in vitro.</p><p><b>METHODS</b>Human bone marrow cells were harvested and cultured in the presence of hepatocyte growth factor (HGF), fibroblast growth factor (FGF) and lymphocyte inhibitory factor (LIF). Cells were stained immunohistochemically by albumin specific antibody and examined under a confocal microscope. Supernatant albumin level was measured biochemically on a serial time points of the culture.</p><p><b>RESULTS</b>By this condition, the attached cells became mature morphologically in 1 week of culture. Hepatocyte-specific albumin could be detected in mature cells. The albumin level revealed a time-dependent change during a 4-week culture.</p><p><b>CONCLUSION</b>Human bone marrow cells could be induced to differentiate to mature hepatocytes that produce and secret albumin in vitro. These cells may contribute to a stable source of hepatocytes for clinical hepatocyte transplantation and artificial liver support system.</p>