Establishment and identification of a mitochondrial tracking system / 中国药理学与毒理学杂志

OBJECTIVE To observe whether mitochondria can be transferred from mesenchymal stem cells(MSCs)to irradiated cells by establishing a mitochondrial fluorescent reporting system.METHODS The lentiviral vector pSIN-EF1α-COX8A-DsRed2(named COX8A-DsRed2)that might guide the expres-sion of red fluorescence protein in the membrane of mitochondria was constructed.A lentivirus(named Lv-COX8A-DsRed2)was prepared in 293T cell line.Dental pulp stem cells(DPSCs)(named DPSC-COX8A-DsRed2)was infected with Lv-COX8A-DsRed2.The intracellular expression of the red fluores-cence protein in DPSC was observed under fluorescence microcopy.The mitochondrial localization of the expressed red fluorescent probe in DPSC-COX8A-DsRed2 was confirmed according to TOMM20 immunostaining and MitoTracker Green staining results,which could specifically label mitochondria.The IEC-6 cells that received 10 Gy X-ray radiation were used as an injured cell model.The co-culture system was established by supplementing DPSC-COX8A-DsRed2 into the culture plate with the irradi-ated IEC-6 labelled by CFSE for 24 h.RESULTS The imaging results of fluorescent microcopy obser-vation showed that DPSC-COX8A-DsRed2 expressed the mitochondrial fluorescent reporting system,which was co-located with TOMM20 protein and Mito Tracker Green.The imaging results of confocal fluorescence microcopy showed that the mitochondria with red fluorescent protein were transferred from DPSC-COX8A-DsRed2 to the irradiated IEC-6 cells,suggesting that the established mitochondrial fluorescent reporting system could indicate mitochondrial transfer from donor cells to injured ones.CONCLUSION DPSC-COX8A-DsRed2 stably expressing the mitochondrial fluorescent reporting system is established,which can be used to track mitochondrial transfer.

Mononuclear cells of umbilical cord blood differentiation to granulocyte cell in vitro / 中华血液学杂志

Objective@#To explore an optimal method for granulocyte cell production from umbilical cord blood mononuclear cells.@*Methods@#Erythrocytes were precipitated by hydroxyethyl starch. Mononuclear cells were isolated through Ficoll density gradient centrifugation. Different media, additives and cultivation model were chosen for granulocyte induction. Cell morphology was observed by microscopy, and cell phenotype was detected by flow cytometry. The CD18 expression of granulocytes was tested by immunofluorescence assay, and phagocytosis test was executed as well.@*Results@#Compared to fetal bovine serum (FBS) treatment group, cell viability, counts and differentiation rate of granulocytes induced by X-VIVOTM 15 combined with TPO, SCF, G-CSF but without FBS were superior. And X-VIVOTM15 medium was better than SCGM medium at effectiveness and cost. Using two-stage mode of hematopoietic stem cell expansion followed by granulocyte induction with X-VIVOTM15 combining TPO, SCF and G-CSF, cell proliferation was nearly 132 times at day 21. Flow cytometry showed that the differentiation was lagged in 2-stage mode than in direct induction mode, CD15 expression was (69.60± 1.06) % vs (97.73±0.39) %; Wright-Giemsa staining demonstrated mature granulocytes; immunofluorescence showed the expression of lysosomal proteins CD18. A strong phagocytic function of mature granulocytes was demonstrated by phagotrophic efficiency of (51.43±0.05) %. And granulocyte had chemotaxis ability under the role of chemotactic factor IL-8.@*Conclusion@#Optimized culture media and cultivation mode are achieved for functional granulocytes induction in vitro.

Role of bone marrow mesenchymal stem cells in repair of neural cell injury induced by okadaic acid / 解放军医学杂志

Objective To study whether the human bone marrow mesenchymal stem cells (HBMSCs) can repair damaged neural cells induced by okadaic acid (OA).Methods Neuroblastoma cell line SH-SY5Y cells were used to incubate with 20nmol/L okadaic acid for 24h,establishing Alzheimer's Disease cell model;Three groups were set up:normal group,okadaic acid-damaged (OA-damaged) group,hBMSCs-treatment group.The cells were injured for 24h with 20nmol/L OA in OA-damaged group,and treated with conditioned medium obtaining hBMSCs for 24h after 24h OA injury in the treatment group.Then CCK-8 was used for detecting cell vitality,immune fluorescence dyed microtubules and micro filaments for determining the dendritic cell length and fluorescence intensity,in addition,Western blotting for analyzing the protein level of phosphorylated tau and total tau proteins.Results Okadaic acid damaged SH-SY5Y cells,contributed to shrinkage,collapse,cavitation of the SH-SY5Y cell body,dendritic shortening and fracture,and irregular arrangement of microtubule microfilaments;while BMSCs conditioned medium made SHSYSY cell body become round and longer,dendrites restored,and microtubules and microfilaments arranged regularly,fluorescence intensity enhanced.Meanwhile,it also down-regulated the level of OA-induced tau phosphorylation.Conclusion hBMSCs have repair effects on the neural cell damage induced by okadaic acid.

The induction and cryopreservation of erythroid progenitor cells derived from umbilical cord blood mononuclear cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To discover the techniques for ex vivo generation and cryopreservation of erythroid progenitor cells (EPCs)derived from umbilical cord blood (UCB)mononuclear cells (MNCs).</p><p><b>METHODS</b>UCB was chosen as the source of EPCs. Erythrocytes were precipitated by hydroxyethyl starch (HES). MNCs were separated by Ficoll density gradient centrifugation. Erythroid progenitor cell were generated from MNC ex vivo in suspension culture supplemented with stem cell growth factor, insulin growth factor, erythropoietin, Fms- liketyrosinekinase ligand, transferrin and dexamethasone. Cell maturation was evaluated by morphologic analysis and CD71/CD235a expression profiling. In vitro induced cells were cryopreserved using different cryopreservation media. The cell survival rate, phenotype and proliferation curves were detected after cell thawing.</p><p><b>RESULTS</b>With the extension of culture time, the total number of cells increased significantly accompanied with the elevation of CD71 and CD235 positive populations. After 14- day inducing, the cells reached to approximately 110 times of the starting number with the cell viability as (88.92±0.95)%. The percentages of cell surface markers were (86.77±9.11)% for CD71 and (64.47±16.67)% for CD71/CD235, respectively. With the extension of inducing time, wright- Giemsa staining showed that the middle erythroblasts appeared mostly at day 10, and the late erythroblasts were seen at day 14. The red pellets were present at day 14, which indicated the more production of hemoglobin. Colony forming assay showed that erythroid colonies at induction day 7 were higher than that for non-induced cells (326.00±97.96vs 61.60±20.03 per 2 000 cells). With the extension of culture time, the number of erythroid colonies decreased. Induced EPCs were preserved with different cryopreservation solutions, in which 10% DMSO were better than 5% DMSO. Additionally, 10% DMSO + 2% HSA showed no different with 10% DMSO + 5% HSA. Combined 50% plasma with 2% HSA was more effective.</p><p><b>CONCLUSIONS</b>This non- serum culture media could effectively induced and expanded EPCs, and 10% DMSO + 2% HSA + 50% plasma appeared to be a desirable cryopreservation solution for EPCs from UCB.</p>

Induced differentiation of rat kidney stem cells into renal tubular epithelial cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the differentiation capability of kidney stem cells (KSCs) into renal tubular epithelial cells (RTECs).</p><p><b>METHODS</b>KSCs isolated from the renal papilla of 4-week-old SD rats were co-cultured with hypoxia-exposed RTEC in induced medium (containing activin A, BMP-7, and retinoic acid) and renal epithelial cell growth medium (REGM) alternately. The KSCs cultured in MSC medium served as the control. The KSC differentiation rates in both groups were determined using flow cytometry, immunofluorescence assay and qRT-PCR.</p><p><b>RESULTS</b>Flow cytometry showed a CK-18 positive rate of 6.5Percnt; in the control KSC group and of 44.2% in the induced group. Immunofluorescence assay detected the positivity for mature epithelial cell markers CK-18, E-cadherin, and ZO-1 in the induced cells. The results of qRT-PCR showed significantly increased expression of E-cadherin and AQP-1 mRNAs in the induced cells compared with the control cells (P<0.01).</p><p><b>CONCLUSION</b>Rat KSCs can be induced to differentiate into RTECs in vitro.</p>

Study on the induction and differentiation of megakaryocyte progenitor cell derived from umbilical cord blood / 中华血液学杂志

<p><b>OBJECTIVE</b>To build a protocol of separation and induction of megakaryocytes derived from cord blood mononuclear cells.</p><p><b>METHODS</b>Red blood cells were precipitated by hydroxyethyl starch (HES). Mononuclear cells were obtained by density gradient centrifugation with Ficoll. The inducing efficiencies of megakaryocytes by using of different cytokine cocktails and culture media were analyzed.</p><p><b>RESULTS</b>The best choice for erythrocyte sedimentation and high efficiency of nucleated cells retrieving were obtained by using of 1.5% HES. The isolated cord blood mononuclear cells were cultured with domestic serum-free medium supplemented with 116t (IL-11, IL-6, TPO), st36(SCF, TPO, IL-3, IL-6), pt36 (PDGF,TPO,IL-3,IL-6) or pst36 for 7 days. St36 group (50 ng/ml SCF, 50 ng/ml TPO, 20 ng/ml IL-3 and 50 ng/ml IL-6) yielded the most CD41/CD61 positive [(6.79±1.97)×10⁴]. The cell viability [(82.85 ± 0.64)%] of st36 group by using of imported serum-free medium was better than [(60.90±6.93)%] that in domestic medium on day 7 after induction, and CD41/CD61 positive cells count [(18.60±1.97)×10⁴] were more than domestic serum-free medium group. Therefore, we chose imported serum-free medium containing st36 to induce cord blood mononuclear cells. After a prolonged culture, the total cell numbers increased accompanied with an elevated percentage of CD41/CD61 positive cells, which reached (54.27 ± 6.31)% on day 14. Wright-Giemsa staining showed that different phase cells, such as megakaryoblast, promegakaryocyte and granular megakaryocyte, occurred after 10 days'culture. Clone forming unit-megakarocytes (CFU-MK) assay showed that the colonies count increased with the prolonged incubation. CFU-MK colonies were [1 236.0±32.9] on day 14, which was higher than that in medium without induction (P<0.01). Platelets from megakaryocytes showed agglutination function after 10 days'culture.</p><p><b>CONCLUSION</b>1.5% HES was the best solution to precipitate erythrocytes. The combination of an imported serum-free medium with IL-3, IL-6, SCF and TPO showed better induction efficiency than domestic medium or other cytokine cocktails. Meanwhile, induced megakaryocytes produced functional platelets.</p>

Expression and purification of spindlin 1,a novel cancer related protein,and preparation of its polyclonal antibody / 中国药理学与毒理学杂志

OBJECTIVE Toprepareapolyclonalantibodyforspindlin1protein,anovelcancer related protein,and to provide the data for a better understanding of its functions and screening tu mor. METHODS Purifiedspindlin1proteinwasinjectedintorabbitstoproducethepolyclonalantiserumafter removing glutathione S-transferase (GST)from the fusion protein spindlin 1-GST that was expressed in Escherichia coli..The antiserum was purified through the Hitrap Protein A system,and the titer of spin-dlin 1 polyclonal antibody was detected by ELISA.The specificity of the polyclonal antibody was deter-minedbyWesternblottingandimmunohistochemistry.RESULTS Thetiterofspindlin1polyclonalanti-body was 1∶2000.Western blotting detection demonstrated that the spindlin 1 polyclonal antibody recog-nized myc-spindlin 1 reco mbinant fusion protein in HeLa cells transfected with pAdeasy-myc-spindlin 1 , which also corresponded with Myc.antibody.The HeLa cells were transfected with enhanced green fluo-rescence protein (EGFP)and spindlin 1 vector(pEGFP-C3-spindlin 1 ),which was confirmed by the in-dependent GFP fluorescence assay.The results of immunohistochemistry detection with the spindlin 1 polyclonal antibody suggested that spindlin 1 was mainly expressed in the nuclei of HeLa cells.More i m-portantly,in i mmunohistoche mical assays,the spindlin 1 antibody recognized nuclear spindlin 1 expres-sioninclinicalovariancancertissues.CONCLUSION Thespecificspindlin1polyclonalantibodyispre-pared,which may be used to detect cancer-related protein spindlin 1 in HeLa cells and ovarian cancer tissues.

Lgr5 and CD44 expressions in different types of intestinal polyps and colorectal cancer / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the expression of tumorigenesis-related stem cell markers Lgr5 and CD44 in different pathological types of intestinal polyps and their clinical significance in predicting tumorigenesis.</p><p><b>METHODS</b>A total of 145 cases of colorectal polyps, adenomas and cancer tissues were obtained by colonoscopy biopsy. Immunohistochemistry was employed to detect the expression of Lgr5 and CD44 to analyze their relationship with the occurrence and prognosis of colon and rectal cancer.</p><p><b>RESULTS</b>The expression of CD44 in colon cancer tissue was 95.65%, significantly higher than that in normal mucosa (5%), inflammatory hyperplastic polyps (22.58%), tubular adenomatous polyps (55.26%) and villous polyps (75.76%) (P<0.05). The expression of Lgr5 in colorectal cancer was up to 95.65% while negative in normal colorectal tissue and was 16.12% in inflammatory hyperplastic tissues (P<0.05). The expression rate of Lgr5 was 86.84% in tubular adenoma and 93.94% in villous polyps, both comparable with that in colon cancer (P>0.05). Correlation analysis indicated that the expression of CD44 and Lgr5 were positively correlated with the progression of intestinal polyp tumorigenesis (rs=0.69377, P<0.0001; rs=0.81637, P<0.0001).</p><p><b>CONCLUSION</b>Lgr5 and CD44 are highly expressed in colorectal cancer tissues in close correlation with the clinical and pathological features. The expression profiles of Lgr5 and CD44 represent a distinct feature to differentiate colorectal cancer from normal intestinal mucosa. Lgr5 is more closely correlated with tumor progression of polyps than CD44. This means detecting of the expression of Lgr 5 together with CD44 is important and necessary in clinical diagnosis of patients with early stage colorectal diseases such as polyps and their canceration.</p>

Effects of different culture conditions on isolation and expansion of stem cells from second-trimester amniotic fluids / 中华妇产科杂志

Objective To investigate the effects of different culture conditions on the isolation and expansion of stem cells from second-trimester amniotic fluids.Methods Amniotic fluids were obtained from 15 pregnant women undergone amniocenteses for medical indications between 16-24 gestation weeks by transabdominal amniocenteses from September 2007 to June 2008.Amniotic fluids(10-20 ml)samples were collected and each WaS cultured under different conditions or groups.(1)Low-glucose DMEM(LD) medium supplemented with 10%of fetal bovine serum(group of 10% FBS);(2)LD medium with 20%of FBS(group of 20%FBS);(3)LD medium with 15%of FBS and 4 ng/ml of basic fibroblast growth factor (group of bFGF);(4)LD medium with 10%of FBS as well ag the culture plate coated with gelatin(group of gelatin).The effects of different conditions were evaluated by comparing the number of primary colonies,the cell morphology and the ability of expansion.The isolated stem cells were identified by flow cytometry,RT-PCR and differentiation ability to edipocyte.Resuits (1)The success rates of primary culture of the group of 10%FBS,20%FBS,bFGF and gelatin were 60%,73%,73%and 60% respectively(P>0.05).The numbers of colonies were 0.9±0.5,2.6±1.5,2.9±1.5,1.1±0.8(P<0.01 when group of 10%FBS and gelatin compared with group of 20%FBS and bFGF);among the primary colonies,fibroblast-like colonies accounted for 46%,49%,64%.44%respectively(P>0.05).(2)The second passage cells obtained from all of these four groups could difierentiate into adipocyte after induction.(3)In the group of bFGF,stem cells were isolated from 5 samples and expanded to nearly 107 cells after 5 passages(P<0.01 compared with other groups).(4)Karyotype were normal in all samples.(5)Stem cells from bFGF group showed positive expression of SSEA-4.Oct-4 and Nanog gene detected by flow cytometry and RT-PCR.Conclusion Stem cells can be isolated from second-trimester amniotic fluids;moderate serum concentration and supplementation of bFGF can improve the efficiency of isolation and expansion of amniotic fluid of stem cells.

Egr-1 promoter regulating effect on granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression induced by doxorubicin and ionizing radiation / 中华放射医学与防护杂志

Objective To explore the regulating effects of Egr-1 promoter activated by ionizing radiation (IR) and doxorubicin (ADM) on the expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) genes. Methods The human GM-CSF cDNA and enhanced green fluorescent protein (EGFP) cDNA were linked together with IRES(internal ribosome entry site) and then inserted into the expression vector pCIneo under control of the Egr-1 promoter(Egr-EG). The vector was transferred into human bone marrow stromal cell line HFCL by liposome transfection. And the cells were exposure to ADM and IR. The activity of EGFP in HFCL/EG cells were detected by FACS. The effect of N-acetylcysteine on the expression of EGFP following exposure to ADM and IR was examined. The amounts of GM-CSF in HFCL/EG after chemotherapy or radiation were measured with ELISA. The effects of GM-CSF in HFCL/EG cultural supernatants on expansion of CFU-GM derived from cord blood were also studied. RT-PCR analysis for the expression of GM-CSF mRNA in HFCL/EG after exposure to ADM or IR. Results The percentage of EGFP+ HFCL/EG cells exposed to ADM and IR was increased compared with non-treatment group (1.2 % and 15.2 % vs 18.2 %, t = 5.11, P < 0.01). The levels of secreted GM-CSF in HFCL/EG cells exposed to ADM and IR was increased (P < 0.01), but no difference between ADM group and IR group (P 0.05). The expression of EGFP by HFCL/EG treated with ADM and IR was significantly decreased by N-acetylcysteine. The effects of GM-CSF in HFCL/EG cultural supernatants on expansion of CFU-GM in ADM group and IR group were significantly higher than that in HFCL group and non-treatment group. However, The CFU-GM count of IR group was higher than that of ADM group. The expression of GM-CSF mRNA in HFCL/EG cells exposed to ADM and IR was significantly increased(t = 4.37, P < 0.01). Conclusions GM-CSF gene expression regulated by Egr-1 promoter induced by ADM and IR could help the recovery from hematopoietic injury.

Sensitized dendritic cells with apoptotic hepatoma cells induced by mitomycin / 中国组织工程研究

BACKGROUND: Dendritic cells play an important role in antigen present in vivo, and the mechanism of tumor cells in escaping the antigen presentation of dendritic cells existed in the patients with tumor.OBJECTIVE: To sensitize dendritic cells from human peripheral blood with apoptotic hepatoma cells induced by mitomycin.DESIGN: A randomized control trial by taking apoptotic hepatoma cell sensitized dendritic cells as the observed subjects.SETTINGS: Institute of Field Surgery, Daping Hospital, the Third Military Medical University of Chinese PLA; Institute of Radiation Medicine,Chinese PLA Academy of Military Medical Sciences.MATERIALS: The experiments were carried out in the Institute of Radiation Medicine, Chinese PLA Academy of Military Medical Sciences from April 1998 to May 1999. The cell strain was the QBC939 bile duct cancer cell strain, and mitomycin was used as the antitumor drug.METHODS: Mononuclear cells were isolated from the peripheral blood of normal people, 50μg/L granulocyte-macrophage colony stimulating factor(GM-CSF) and 1 000 U/mL interleukin-4 (IL-4) were added, once every other day for 4 times. On the 3rd day of culture, the apoptotic bile duct cancer cells induced by mitomycin was added, and then cultured in vitro for 4 days, finally the dendritic cells were collected.MAIN OUTCOME MEASURES: ① The identification of the cultured dendritic cells was observed; ② The dendritic cells were co-cultured with necrotic and normally cultured bile duct cancer cells respectively, and the phagocytized apoptotic body loaded antigens were observed; ③ The immunostimulatory activity of dendritic cells (1×103, 5×103 and 1×104/well)and that after loaded by antigen were detected, and the mononuclear cells were taken as controls.RESULTS: ① The cultured and amplified dendritic cells expressed high levels of costimulatory molecules of CD1a and B7, and there were typical irregular processes on the surface. ② The tumor cells formed apoptotic bodies when they were induced by mitomycin, which were arrested and phagocytized by dendritic cells. ③ The ability of the antigen loaded dendritic cells in stimulating the proliferation of allogenic lymphocyte T was further enhanced.CONCLUSION: The apoptotic tumor cells induced by mitomycin can induce the mononuclear cells from human peripheral blood differentiating into the dendritic cells with the concomitance of GM-CSF and recombinant IL-4 and amplify dendritic cells. Meanwhile, the dendritic cells can effectively present the antigens of apoptotic bile duct cancer cells, and it probably becomes a new effective approach for tumor antigen to sensitize dendritic cells.

Wnt3a is Important in The Differentiation From Neural Stem Cell Into Dopaminergic Neuron In vitro / 生物化学与生物物理进展

Wnt signaling is implicated in the control of cell growth and differentiation during neural stem cell(CNS) development.Wnt3a, one of wnt gene family members, has effect on regeneration neurospheres and differentiation into neurons.Wnt3a inhibits regeneration of neurospheres, and promotes its differentiation. In vitro neurosphere was cultured in a serum-free defined medium DMEM/F12 supplemented with bFGF and EGF. Dissociated cells were plated onto poly-d-lysine-coated coverslips and propagated in medium containing recombined Wnt3a-adenovirus. Plenty of Nurr1 were detected by RT-PCR after 3 days. Wnt3a combined AA would improve NSC differentiation into dopaminergic (DA) neuron. The quantity of DA neuron is obviously more than the AA alone group's. Moreover, the expression of TH mRNA is 1.86 fold in Wnt3a combined AA group. Induced cells were immunostained for TH and DAT. The proportion of TH-positive was (37.42 ? 2.54) % (P

Treatment of Parkinson disease-like rat model by neural stem cell transplantation / 基础医学与临床

Objective To investigate the survival, differentiation and action of neural stem cell transplanted into striatum of Parkinson disease rat model. Methods Neural stem cells were isolated and cultured. The character of self-renewing was confirmed by technique of single cell clone culture. The ability of multi-directional differentiation and specific antigen-nestin was showed by immunocytochemistry(ICC). PD rat models were established, and the DAPI-labelled neural stem cells were transplanted into striatum. The 6-HHDA induced rotary behavior was measured, distribution and migration of the cell were checked by fluoresce activating. ICC and HPLC are used to see its differentiation and action of secrete neurotransmitter dopamine(DA) and it’s metabolites. Results The cultured stem cell express nestin and have the ability of self-renewing and multi-directional differentiation. 6-HHDA induced rotation decreased after transplantation of NSC into the PD rat striatum(P

NRSF Plays a Regulatory Role in Human Insulin Gene Transcription / 生物化学与生物物理进展

The transcriptional repressor RE1 silencer transcription factor(NRSF/REST) is an important factor that restricts some neuronal traits in neurons.Since these traits are also present in pancreatic islet cells,NRSF-regulated genes involved in islet function are searched.A NRSE-like motif was analysed in human insulin promoter.The role of NRSE was evaluated by generating a model of insulin-secreting cells that firmly express NRSF.The presence of NRSF led to a decrease in activity of human insulin promoter by stable or transient transfection with human insulin-promoter luciferase.The predicted NRSE-like motif also confers NRSF-dependent transcriptional repression in the context of a surrogate gene promoter.Specific binding activity of NRSF/REST to the NRSE-like motif was confirmed by EMSA.Moreover,the binding activity is competed by consensus NRSE sequence.These data showed that human insulin promoter is regulated by the transcriptional repressor NRSF/REST via the NRSE-like motif.

Differentiation of Hematopoietic Stem/Progenitor Cells From Embryonic Stem Cells / 生物化学与生物物理进展

Embryonic stem cells(ESCs) are pluripotent cells derived from the inner cell mass of blastocyst-stage embryos, possessing permanent self-renewal and indefinite proliferative capacity in vitro. And ESCs could differentiate into the hematopoietic cell fate. Therefore ESCs may provide an alternative for hematopoietic stem cell transplantation and blood cells transfusion. Furthermore, ESCs differentiation could also provide a powerful model system to better understand the hematopoietic development and the mechanism involved. The current status for efforts to differentiate ESCs into hematopoietic lineages were reviewed.

Cardiomyocyte-like differentiation of human bone marrow mesenchymal stem cells after exposure to 5-azacytidine in vitro / 老年心脏病学杂志（英文版）

Objective To investigate the potential of adult mesenchymal stem cells (MSCs) derived from human bone marrow to undergo cardiomyogenic differentiation after exposure to 5-azacytidine (5-aza) in vitro. Methods A small bone marrow aspirate was taken from the iliac crest of human volunteers, and hMSCs were isolated by 1.073g/mL Percoll and propagated in the right cell culturing medium as previously described. The phenotypes of hMSCs were characterized with the use of flow cytometry. The hMSCs were cultured in cell culture medium (as control) and medium mixed with 5-aza for cellular differentiation. We examined by immunohistochemistry at 21 days the inducement of desmin, cardiac-specific cardiac troponin I (cTnI), GATA 4 and connexin-43 respectively. Results The hMSCs are fibroblast-like morphology and express CD44+ CD29+ CD90+ / CD34- CD45- CD31- CD11a. After 5-aza treatment, 20-30% hMSCs connected with adjoining cells and coalesced into myotube structures after 14days. Twenty-one days after 5-aza treatment, immunofluorescence showed that some cells expressed desmin,GATA4, cTnI and connexin-43 in 5,10 μmol/L 5-aza groups, but no cardiac specific protein was found in neither 3μmol/L 5-aza group nor in the control group. The ratio of cTnI positively stained cells in 10 μmol/L group was higher than that in 5 μmol/L group (65.3 ± 4.7% vs 48.2 ± 5.4%, P ＜ 0.05). Electron microscopy revealed that myofilaments were formed. The induced cells expressed cardiac-myosin heavy chain (MyHC) gene by reverse transcription-polymerase chain reaction (RT-PCR). Conclusions Theses findings suggest that hMSCs from adult bone marrow can be differentiated into cardiac-like muscle cells with 5-aza inducement in vitro and the differentiation is in line with the 5-aza concentration. (J Geriatr Cardiol 2004;1(2) :101-107. )

The plasticity of adult stem cells and their application in myocardial regenerative medicine / 老年心脏病学杂志（英文版）

Current therapies for myocardial infarction and congestive heart failure are limited in efficacy or in applicability. The plasticity of adult stem cells and cellular transplantation offer a novel therapeutic approach to improve cardiac function. This review describes the latest progress in research, summarizes recent studies of adult stem cells and their application in myocardial regenerative medicine in China and abroad, and discusses the future directions of cell transplantation as a new therapy to repair injured hearts. (J Geriatr Cardiol 2004;1(2) :77-82. )

Studies on the expression of hematopoietic growth factor modulated by Egr-1 promoter sequence in transcriptional targeting by chemotherapeutic agents / 解放军医学杂志

Objective To explore the chemotherapeutic agents-induced modulating effects of Egr-1 promoter sequence on GM-CSF expression and its protective effect against injury to haematopoiesis due to chemotherapy.Methods Human GM-CSF cDNA and enhanced green fluorescent protein(EGFP) cDNA were linked to internal ribosome entry site(IRES) respectively,and then recombined to pCIneo vector containing Egr-1 promoter(Egr-EG).The vector was transferred into human bone marrow stromal cell line HFCL by lipofection,and the HFCL/EG cells were then finally constructed.MTT assay was performed to determine the effects of cisplatin(DDP),5-fluorouracil(5-FU),gemcitabine(GEM) and paclitaxel(PTX) on the survival rates of HFCL/EG and HFCL cells,and the IC50 of such agents against HFCL/EG and HFCL cells were calculated.The percentage of HFCL/EG cells which positively expressed EGFP was assessed by both flow cytometry and inverted fluorescence microscope.The effects of the active oxygen inhibitor N-acetylcysteine(NAC) on the expression of GM-CSF,which was modulated by promotor Egr-1,were detected by ELISA.The effects of HFCL/EG supernatant on CFU-GM after being exposed to chemotherapeutic agents were examined.Results With different sensitivity to DDP,5-FU,GEM and PTX,HFCL/EG cells were successfully constructed.The drugs showed higher IC50 value against HFCL/EG cells than HFCL cells(P

Degeneration of Dendritic Cells from Human Peripheral Blood and Acquirement Antigen from Apoptotic Hepatochlangioma Cells / 中国肿瘤临床

Objective:To eastablish the efficient presentation of antigen from apoptotic cells by human DC from peripheral blood. Methods: using recombinant human granulocyte/macrophage colonystimulating factor(GM- CSF) and interleukin 4 (IL- 4 ) we have established dendritic cells (DC)from peripheral blood monocyte that maintain the antigen capturing and processing capacity characteristic of immature dendritic cells in vivo. GM - CSF 50ng/ml , IL- 41 000ng/ml once two days(total four). on the 3 rd day of culture, immature DC and apoptotic hepatochlangioma cells were in coculture lasting 7 days. Results:these cells had typical dendritic morphology, express high levels of CD1a ,B7 and acquired antigen from apoptotic cells and induced an increased T cell stimulatory capacity in MLR. Conclusions:we have established DC from blood mononuclear tells using GM- CSF and IL- 4 and DC can be efficiently drived from apoptotic cells and can induce the increase of T cells obviously. It probably becomes an effective approach of antigen transduced with DC.

The construction of bicistronic eukaryotic vector carrying green fluorescent protein and hytk gene and its expression in bladder carcinoma / 中国病理生理杂志

AIM: To facilitate the suicide gene delivery into neoplasm, a chimeric gene of HSV-tk and green fluorescent protein (gfp) was constructed. METHODS: Molecular cloning technique was used to construct this kind of eukaryotic vector. The internal ribosome entry site (IRES) of encephalomyocarditis virus (EMCV), which could coordinate expression of two genes in a single vector, was optioned. By using liposome-mediated transfection, eukaryotic expression vector tgCMV/hytk-IRES-gfp was transfected into human bladder carcinoma cells EJ. RESULTS: A bicistronic eukaryotic vector carrying gfp and hygromycin phosphotransferase-thymidine kinase fusion (hytk) gene was constructed. The results of PCR and microscopy detection show that the hytk-IRES-gfp gene was successfully transferred into EJ cells. There were no differences in the growth pattern or the morphology between EJ and EJ/hytk-GFP cells. In vitro experiments demonstrated dose- and time-dependent cell killing by transduction of the hytk-IRES-gfp gene followed by GCV treatment. The IC50 (the concentration required to elicit 50% growth inhibition) was 2.16 mg/L in treatment with GCV for 72 hours. CONCLUSION: These results suggest that this new kind of eukaryotic vector could serves as a new tool and method for neoplasm gene therapy.