[Induction of hepatic specification of human adipose-derived stem cells (hADSCs) in vitro].

Objective: To induce hepatic differentiation of human adipose-derived stem cells (hADSCs) in vitro.

Methods: hADSCs were isolated from human adipose tissue and treated with improved hepatic medium containing HGF, bFGF and FGF4. After 7 days of culture, OSM was added to the culture media.

Self-renewal and pluripotency is maintained in human embryonic stem cells by co-culture with human fetal liver stromal cells expressing hypoxia inducible factor 1alpha.

Human embryonic stem (hES) cells are typically maintained on mouse embryonic fibroblast (MEF) feeders or with MEF-conditioned medium. However, these xenosupport systems greatly limit the therapeutic applications of hES cells because of the risk of cross-transfer of animal pathogens. The stem cell niche is a unique tissue microenvironment that regulates the self-renewal and differentiation of stem cells.

Cells extract from fetal liver promotes the hematopoietic differentiation of human embryonic stem cells.

Here, we have now developed a new inducing system to promote the differentiation of human stem cells (hESCs) toward hematopoietic lineages by the treatment with cells extract of human fetal liver tissue (hFLT). The embryoid bodies (EBs) obtained from human H1 embryonic stem cells were exposed to buffer, hFLT cells extract, heated hFLT cell extract, and cell extract of human liver cells lines-LO2. Then, the feature of EBs in different groups was characterized by real-time RT-PCR and colony-forming assays.

Full-thickness tissue engineered skin constructed with autogenic bone marrow mesenchymal stem cells.

To explore the feasibility of repairing clinical cutaneous deficiency, autogenic bone marrow mesenchymal stem cells (BMSCs) were isolated and differentiated into epidermal cells and fibroblasts in vitro supplemented with different inducing factors and biomaterials to construct functional tissueengineered skin. The results showed that after 72 h induction, BMSCs displayed morphologic changes such as typical epidermal cell arrangement, from spindle shape to round or oval; tonofibrils, melanosomes and keratohyaline granules were observed under a transmission electronic microscope. The differentiated cells expressed epidermal stem cell surface marker CK19 (59.

[Cardiomyocyte-like differentiation of human bone marrow mesenchymal stem cells after exposure of 5-azacytidine in vitro].

To investigate the potential of adult mesenchymal stem cells (hMSCs) derived from human bone marrow to undergo cardiomyogenic differentiation after exposure of 5-azacytidine in vitro. A small bone marrow aspirate was taken from the iliac crest of human volunteers, and hMSCs were isolated by 1.073 g/mL Percoll and cultured in the right cell culturing medium as previously described.

[The maintenance of cord blood CD34+ progenitor cells with plant lectin FRIL in vitro and the expression of related cell cycle modulator HTm4 and HTm4S].

Ex vivo maintainance of human stem cells is crucial for many clinical applications. Current culture conditions provide some level support but cytokines induce most quiescent stem cells to proliferate and differentiate. Better control of primitive cells is needed to extend the time and range of manipulation of such cells.

[Migration and differentiation of exogenous rat mesenchymal stem cells engrafted into normal and injured hearts of rats].

Objective: To investigate the effects of different microcircumstances on the migration and differentiation of grafted rat mesenchymal stem cells (rMSC) in host myocardium and the feasibility of treatment of myocardial infarction by exogenous adult stem cells.

Methods: rMSC were isolated from the femurs and tibiae of a male Wistar rat and then purified, made into cell suspension, and labeled with DAPI. 35 female Wistar rat were divided randomly into four groups: acute myocardial infarction control group (AMI group, n = 10, the descending anterior branch of left coronary artery was ligated), acute myocardial infarction + rMSC transplantation group (AMI + rMSC group, n = 10, 1 - 3 hours after the ligation DAPI-labeled rMSC were injected into the peri-infarct tissues), normal heart + rMSC transplantation group (normal heart + MSC group, n = 10, DAPI-labeled rMSC were injected into the corresponding myocardium), and mono-nuclear cells transplantation group (AMI + MNCS, n = 5 DAPI-labeled mononuclear cells were injected into he periinfarct tissues).

[Effect of Tpo and/or IL-11 gene modified stromal cells on the expansion of CD34+ CD38- hematopoietic primitive progenitor cells].

Objective: To investigate the effects of Tpo and/or IL-11 gene modified stromal cells on the expansion of CD(34)(+) hematopoietic stem/progenitor cells in cord blood.

Methods: Retroviral vectors containing Tpo or IL-11 gene were constructed and used to transfect the stromal cell line HFCL. Tpo and/or IL-11 mRNA was assayed by Northern blot.

[Identification of differentially expressed genes in Lin-CD34- and Lin-CD34+ cells].

Objective: To identify genes that differentially expressed in Lin(-)CD(34)(-) and Lin(-)CD(34)(+) cells.

Methods: With Lin(-)CD(34)(-) cells as tester and Lin(-)CD(34)(+) cells as driver, cDNA subtractive library for Lin(-)CD(34)(-) cells was constructed using suppression subtractive hybridization technique. Part of clones in the library were sequenced and the homologue analysis was conducted against the DNA database in GenBank.

[Development of the human/rat chimera model with neonatal rats].

The purpose of this study was to transplant neonatal rat with human cord blood Lin(-) cells to test the possibility of this xenograft model. The Lin(-) cells were purified from human cord blood (CB) using negative selection strategy based on different lineage-specific antigens. The Lin(-) cells were injected into the liver of neonatal rats using a microinjector at an average of 5 x 10(5) cells for each.

[Migration and differentiation of human bone marrow mesenchymal stem cells in the rat brain].

Bone marrow mesenchymal stem cells (MSCs) are multipotent tissue stem cells that can be induced in vitro to differentiate into a variety of cells such as osteoblasts, chondrocytes and adipocytes. MSCs are useful vehicles for both cell and gene therapy for a variety of diseases. Here, we injected human MSCs with enhanced green fluorescent protein (EGFP) into the striatum of Parkinson disease (PD) rat and examined their survival, migration, differentiation, and the behavior changes in PD rats, which will provide a theoretical foundation and technical method for clinic PD therapy by stem cells.

[Construction of fetal mesenchymal stem cell cDNA subtractive library].

Unlabelled: To identify differentially expressed genes between fetal mesenchymal stem cell (MSC) and adult MSC, especially specified genes expressed in fetal MSC, a cDNA subtractive library of fetal MSC was constructed using suppression subtractive hybridization (SSH) technique. At first, total RNA was isolated from fetal and adult MSC. Using SMART PCR synthesis method, single-strand and double-strand cDNAs were synthesized.

[Expression of telomerase during induction of committed differentiation of human cord blood hematopoietic stem/progenitor cells in vitro].

To investigate the expression of telomerase in cord blood hematopoietic stem/progenitor cells during their committed differentiation in vitro and provide an index of monitoring the proliferating potential of the hematopoietic stem/progenitor cells and security for clinical application. Human CD34 positive cells were isolated from umbilical cord blood by using magnetic cell sorting system (MACS), and were induced to differentiation with hematopoietic growth factors (SCF + IL3 + IL6 + GCSF and SCF + IL3 + IL6 + EPO) in a liquid culture system. The telomerase activity and the cytalytic subunit of telomerase (hTERT) of the cells were analysed during different periods of culture by using TRAP-PCR, TRAP-ELISA, Western blot and RT-PCR techniques, respectively.

[Study on granulocytes derived from induction of committed differentiation of hematopoietic stem/progenitor cells ex vivo].

To evaluated the feasibility of preventing infection after high dose chemotherapy and radiotherapy using the granulocytes derived from differentiated from hematopoietic stem/progenitor cells ex vivo, human CD34-positive cells were isolated from umbilical cord blood by using a high-gradient magnetic cell sorting system (MACS), and the cells committedly differentiated with hematopoietic cytokines (SCF + IL-3 + IL-6 + G-CSF) in a liquid culture system. The expanded cell number, ratio of the viable cells, chromosome and phenotype of the differentiated cells and safety analysis of expanded cells were detected by using cell count, trypan blue exclusion test, karyotype analysis, flow cytometry and tumorigenic model of nude mice, respectively. The results showed that the combination of cytokines increased cell number by (1006.