There are plenty of haematopoietic stem cells in umbilical cord blood, which are regarded as important resources for transplantation therapy. There are some arguments on whether or not mesenchymal stem cells(MSCs) exist in umbilical cord blood. Some researchers have such opinions that there exist a number of MSCs in umbilical cord blood as similar with one from bone marrow in many aspects. Others believe that the content of MSCs in umbilical cord blood is too low to expand in vitro. We summarized the data from last five years researches. On umbilical cord blood MSCs during last to help further research and application of this resource of MSCs.

AIM: To explore the possibility of differentiating functional insulin-producing cells from human BM-derived stem cells. METHODS: Mesenchymal stem cells were isolated from human bone marrow. Then these cells were induced with epidermal growth factor, β-mercaptoethanol and high concentration of glucose. The gene expression related to islet β cells was detected by RT-PCR. Insulin in the treated cells was examined by immunocytochemistry. In addition, the levels of insulin secretion and glucose-stimulated insulin release were examined by microparticle enzyme immunoassay. Finally, the induced cells were implanted into the right renal subcapsular space of diabetic mice. Blood glucose levels were monitored 16 d after implantation. The right kidneys of the treated mice were harvested for immunohistochemistry. RESULTS: The key genes related to pancreatic β cells had been confirmed to express by PCR and insulin was detected by immunocytochemistry in differentiated human BM-derived stem cells induced by high glucose, which responded to glucose challenge. Furthermore, implantation of the cells in renal subcapsular space was able to lower the glucose levels in hyperglycemic mice. After 16 days, the implanted cells were determined still to be insulin positive cells by immunohistochemistry. CONCLUSION: These results indicate human BM-derived stem cells are capable of differentiating into functional insulin-producing cells and may represent a pool of cells for the treatment of diabetes.

BACKGROUND: At present,there are many reports regarding the differentiation of bone marrow-derived mesenchymal stem cells or pancreatic gland stem cells into pancreatic islet β-like cells.But little is about umbilical cord blood-derived mesenchymal stem cells(UCBMSCs)differentiation into pancreatic islet β-like cells in vitro.OBJECTIVE: To investigate whether UCBMSCs can differentiate into pancreatic islet β-like cells in vitro and the optimal inducing condition.METHODS: UCB samples were obtained sterilely from healthy parturients.Nucleated cells were isolated by sedimentation with hydroxyethyl starch and MSCs were obtained by adherent method.Then purified UCBMSCs were induced with epidermal growth factor,β-mercaptoethanol,high glucose,Activin A and hepatocyte growth factor(HGF).Following cell morphology observation,induced cells were identified by insulin immunofluorescence.In addition,insulin secretion and glucose-stimulated insulin release were examined by chemiluminescence immunoassay.RESULTS AND CONCLUSION: After induction,many cells exhibited a round appearance and produced islet-like cell clusters.Immunofluorescence assay showed insulin positive in the treated cells.In addition,chemiluminescence immunoassay demonstrated low expression of insulin and secretion of insulin upon glucose challenge.UCBMSCs can differentiate into pancreatic islet β-like cells in vitro.

Objective To discuss the possibility of differentiation of mesenchymal stem cells(MSCs)from umbilical cord blood(UCB)into hepatocyte-like cells in the in vitro culture.Methods MSCs were isolated from UCB,cultured and passaged.The surface markers were examined by flow cytometry.When cells were cultured to the third passage,they were inoculated into a 6-well plate.A two-stage induction method was used:MSCs in the first phase were cultured in DMEM/F12 medium supplemented with dexamethasone(final concentration of 0.5 μmol/L,the same below),hepatocyte growth factor(HGF,10 ng/ml),epidermal growth factor(10 ng/m1)and 1×insulin-transferrin-Se(ITS)for two weeks,then in DMEM/F12 supplemented with 0.5 μmol/L dexamethasone,10 ng/ml HGF,1×ITS,10 ng/ml Oncostatin M for another two weeks.Morphological changes were observed under a microscope.The gene expression correlated with hepatocytes was detected by using RT-PCR.Immunofluorescence staining was used to identify the expression of specific protein related to hepatocytes(AFP,Albumin,CK-18).Ultrastructure was detected under an electron microscope.Results In the cultured MSCs from UCB,CD34/CD45/CD14,CD54,CD49f and HLA-DR were not detected,there was low expression of CD106 and strong expression of CD29,CD44 and CD13.The gene expression of AFP,albumin,CK-18 and TAT was discovered and three kinds of protein AFP,albumin and CK-18 were positively showed in cytoplasm after 4 weeks'induction.The hepatin granules and fatty drops in cytoplasm of cells induced for 4 weeks were found under an electron microscope.Conclusion The MSCs fromUCB can differentiate into hepatocyte-like ceils in the in vitro culture under some conditions.

BACKGROUND: Reproductive activity of hepatocytes is limited. There are numerous studies concerning stem cells differentiation into hepatocytes, including embryonic stem cells, bone marrow cells, pancreas stem cells, neural stem cells, various sources of mesenchymal stem cells.OBJECTIVE: To explore the possibility of induction of mesenchymal stem cells (MSCs) from umbilical cord blood (UCB) into hepatocyte-like cells in vitro culture.DESIGN, TIME AND SETTING: A cytological in vitro study was performed at the Institute of Hematology, Medical College of Jinan University from October 2005 to April 2006.MATERIALS: Fetus cord blood was obtained from spontaneous delivery and caesarean delivered healthy pregnant women at the Department of Obstetrics and Gynecology, First Affiliated Hospital of Jinan University. The parturients signed the informed consents.METHODS: UCB-MSCs were incubated in vitro, and digested in trypsin-EDTA. The third passage of cells at 5 × 10~4 cells/cm~2 wereinoculated. Original medium was removed 48 hours later. Cells were washed in phosphate-buffered saline. In the first phase, cells were incubated in F12 medium supplemented with dexamethasone, hepatocyte growth factor, epidermal growth factor and 1 ×its for 2 weeks. In the second phase, cells were incubated in F12 medium containing dexamethasone, hepatocyte growth factor,oncostatin M and 1 × ITS for two weeks.MAIN OUTCOME MEASURES: The following parameters were measured: expression of surface marker of UCB-MSCs using flow cytometry, expression of related gene and protein of hepatocytes following induction respectively using RT-PCR and immunofluorescence staining.RESULTS: No CD34/CD45/CD14 of hematopoietic markers were detected, either no the CD54, CD49f, HLA-DR were found. The low expression of CD106 and high expression of CD29, CD44, CD13 were found. The gene expression of a-fetoprotein, albumin,CK-18 and TAT were discovered, and three kind of protein a-fetoprotein, albumin, CK-18 were positively observed in cytoplasm after 4 weeks of induction using immunofluorescence staining.CONCLUSION: UCB-MSCs are able to differentiate into hepatocyte-like cells in vitro culture following combination with many growth differentiation factors, such as dexamethasone, hepatocyte growth factor, epidermal growth factor, tumorigenesis M and ITS.

Objective To investigate the synaptopathy of hidden hearing loss mice,and to observe the synapses of the cochlear inner hair cell after temporary threshold shift of noise exposure.Methods Mice were divided into normal control group and experiment group,the latter was exposed under noise of 98 dB SPL for 2 h to establish the model of temporary threshold shift.Mice cochleae of the two groups were dissected and prepared with whole mount and immunostaining.Cellular morphology was observed under confocal laser scanning microscope.Cochlear lengths were measured through cochlear frequency map to localize hair cells in different frequency regions.Then,3-D morphometry of synapses was constructed by Amira software to observe pre-synaptic ribbons,post-synaptic receptors and its pathological changes.Results In control group,each cochlear nerve fiber contacted a single inner hair cell by a single synapse,each inner hair cell had 5-30 synapses contacting cochlear nerve fibers.The larger ribbons patched smaller receptors located in the modiolar side,and the smaller ribbons patched larger receptors located in the pillar side.While in experiment group,noise overexposures caused moderate or completely reversible thresholds shift,i,e.,distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) thresholds increased 30-40 dB.Although returned to normal after 2 weeks,ABR wave Ⅰ amplitudes recovered to only 46.1 ％ of pre-exposure amplitudes.There was 41.3％ synapses loss of inner hair cell,but there was no loss of inner hair cells and spiral ganglion neurons.Conclusions Threshold test is not sensitive to degeneration and loss of synapse in mice inner hair cells,while super threshold test is sensitive to it.

Objects To observe whether mesenchymal stem cells exist in umbilical cord blood and if they can differentiate into osteoblasts and adipocytes.Methods Nucleated cells were separated with Hespan,Mesenchymal-like stem cells were identified by surface marker with flow cytometry.Osteoblast was identified by von Kossa staining and alkaline phosphatase staining,adipocyte was identified by Oil Red O staining.Results From the Nucleated fraction of UCB,we demonstrated the presence of a subset of cells that express adhesion molecules CD13+,CD29+,and CD44+,but not antigens of hematopoietic CD34,CD45,CD14 and neither antigens of endothelia CD106.Exposure of these cells to osteogenic inductive agents resulted in an increase in the expression of alkaline phosphatase and the appearance of hydroxyapatite nodules by Von Kossa staining.Incubation with adipogenic inductive agents resulted in morphological change and positive staining with oil Red O.Conclusions Mesenchymal-like stem cells exist in cord blood and have a lower precursor frequency.The cells can differentiate into osteoblast and adipocyte.Cord blood may function as a new source of cells for cellular therapeutics.

Child ; Humans ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; therapy

Animals ; Cochlea ; growth & development ; metabolism ; Female ; Guinea Pigs ; Male ; Nerve Growth Factor ; metabolism

Objective To analyze the clinical efficacy of balloon occlusion of distal abdominal aorta for patients with pernicious placenta previa and placenta accreta.Methods Data of 72 patients with pernicious placenta previa and placenta accreta were retrospectively analyzed.There were 53 cases (occlusion group) reserved balloon occlusion in abdominal aorta before cesarean section,which can temporarily blocked abdominal aortic blood flow during operation.The other 19 cases (non-occlusion group) underwent cesarean section without balloon occlusion of abdominal aorta.The intraoperative,post operative situations and the birth state of newborn of the two groups were compared.Results The bleeding,blood transfusion and hysterectomy rate during the operation in occlusion group were less than those in non-occlusion group (all P＜ 0.05).Differences of the rate of postoperative transferring to intensive care unit (ICU) and the time in ICU were statistically significant between two groups (both P ＜0.05).No statistical difference of operation time,postoperative total hospital stay time and the rate of postoperative infection was found between two groups (both P＞0.05).There was no statistical difference of newborns weight and Apgar scores (5 min and 10 min after birth) between two groups (all P＞0.05).Conclusion The balloon occlusion of distal abdominal aorta in cesarean section for patients with pernicious placenta previa and placenta accreta is safe and feasible,which can effectively reduce the intraoperative bleeding,the blood transfusion and the risk of hysterectomy.