To investigate the osteogenic and adipogenic difference of bone marrow-derived mesenchymal stem cells (MSCs) between patients with aplastic anemia (AA) and healthy volunteers and to explore the role of MSCs adipo-differentiation in the pathogenetic mechanism of AA.

To investigate the effects of umbilical cord mesenchymal stem cell (UC-MSCs) transplantation on interstitial pneumonitis in MRL/lpr mice.

To investigate the efficacy of tissue-engineered bone (human BMP-2 genetic modified BMSC combined with coral) in healing the segmental orbital defect in rabbits.

To evaluate the osteoblastic differentiation and compare the difference in the gene expression of rat bone marrow mesenchymal stem cells (MSCs) affected by a single period of mechanical strain.

To study the morphologic and growing alterations of oral cancer cell line Tca8113 before and after cocultured with tumor stromal fibroblasts (TSF) and normal stromal fibroblasts (NSF) respectively, and evaluate the influence of mesenchymal cells on tumor cells.

To study the proliferation and differentiation of neural stem cells in the subventricular zone (SVZ) in neonatal rats after bilateral common arteries occlusion.

To investigate the effect of allo-HSCT irradiation preconditioning on the homing of donor endothelial progenitor cells (EPCs).

To investigate the differentiation of rat bone marrow mesenchymal stem cells (MSCs) into myocytes and their expression of dystrophin/utrophin after transplantation in mdx mice.

To establish a rat model of full-thickness skin defect to receive bone marrow mesenchymal stem cell transplantation for wound repair.

To construct the lentiviral RNA interference (RNAi) vector of rat CXCR4 gene, three target sequences were selected according to rat CXCR4 mRNA sequence, the complementary DNA contained both sense and antisense oligonucleotides were designed and synthesized. After phosphorylation and annealing, these double-strand DNA were cloned to Bgl II and Hind III sites of pSUPER. Then the product pRiCXCR4 was confirmed by electrophoresis and sequencing. Next, CXCR4 shRNA was cloned to a transfer vector of lentivirus, pNL-EGFP, and pNL-RiCXCR4-EGFP was produced. It was confirmed by digestion and sequencing that CXCR4 shRNA expression structure was correctly cloned to pSUPER and pNL-EGFP respectively. Three plasmids, pNL-RiCXCR4-EGFP, pHELPER and pVSVG were cotransfected into 293T to package lentivirus particles. The functional titer of obtained virus was determined by flow cytometry after transduction in 293T, the resulting functional titer of unconcentrated virus and concentrated virus were 6.4 x 10(4) TU/mL and 6.9 x 10(6) TU/mL respectively. After the rat mesenchymal stem cells (rMSCs) were transduced with the constructed lentiviral vectors, real-time RT-PCR, Western blotting and flow cytometry were used to evaluate the level of CXCR4 expression. Compared with control group, the CXCR4 mRNA expression were obviously suppressed in all three experimental groups (rMSCs-CXCR4a, rMSCs-CXCR4b, rMSCs-CXCR4c), especially the expression rate in rMSCs-CXCR4b group was reduced by 95.6%. The RNAi lentivirus vector of rat CXCR4 gene has been constructed successfully. This greatly facilitates the further studies such as evaluation the role of CXCR4 in rMSCs recruitment to damaged tissue.

Male germ-line stem cells (mGSCs) have the capability of self-renewal and latent capability of differentiation. mGSCs is the unique diploid immortal cell which can transfer genetic information to filial generation. The combination of transgenic technology and mGSCs heterotransplanting will supply new opportunities and paths to cloning animal, transgenic animal and gene therapy of some human hereditary disease. We studied the isolation and cultivation of mGSCs that were isolated and purified from 5-6 month old bovine fetal testis, new born bovine testis by adopting mixed enzymes digestion and different attaching velocities methods. The results showed that Sertoli cells were indispensable to mGSC's proliferation and differentiation in vitro. The Sertoli cells in logarithmic phase have a significant effect on mGSC's attaching, proliferation and differentiation. Co-culture with Sertoli cells, mGSCs differentiated to long sperm after 16 days. A preliminary system for mGSC's inducing differentiation was established.

In order to investigate the transfer and expression of Snail gene in human bone mesenchymal stem cells (MSCs) and to study effects of Snail gene modification on the CXCR4 expression of human MSCs and their capacity of migration to SDF-1 in vitro, the plasmid PCAGGSneo-Snail-HA or the control vector of PCAGGSneo was transferred into the cells. Fluorescence activated cell sorting analysis, immunofluorescence staining and RT-PCR were used to study the expression of CXCR4 by MSCs. Chemotaxis assays were performed to evaluate the migratory capacity of MSCs-Sna and MSCs-neo to SDF-1 in vitro. For the blocking assay, CXCR4 blocking antibody was added into cell culture. CXCR4 expression was higher in MSCs-Sna than that in MSCs-neo (P < 0.05). Chemotaxis assays showed that SDF-1alpha stimulated migratory activity of MSCs-Sna more than MSCs-neo in vitro (P < 0.05). Moreover, the SDF-1alpha-induced migratory activity of MSCs-Sna was inhibited in a concentration-dependent manner by a CXCR4-blocking antibody. It was concluded that Snail enhanced expression of CXCR4 in MSCs, providing a plausible mechanism for Snail-mediated MSCs transmigration to damaged tissues in vivo where SDF-1 has been shown to be up-regulated as part of injury responses.

To study the proliferation effect of neural stem cells (NSCs) of ginsenoside Rg1 in vitro.

This study is aimed to design a chemically-defined serum free medium (CDSFM) to support in vitro culture of bone marrow-derived mesenchymal stem cells (BM-MSCs). BM-MSCs were isolated from the femoral bones of one-month-old New Zealand Rabbits with density gradient centrifugation. We compared the proliferation capability, cell cycle, colony-forming efficiency, osteogenic and adipogenic differentiation capabilities of BM-MSCs cultured in CDSFM with those cultured in serum-containing medium (SCM). After 10 days culture, BM-MSCs were expanded by 50 folds in CDSFM, while only 40 folds in SCM. EGF, bFGF and hy-drocortisone were the most important additives and significantly stimulated BM-MSCs proliferation. The percentage of cells at G0-G1 cell cycle was 80.31% +/- 0.58% after CDSFM culture, with no significant difference (P>0.05) compared to 75.24% +/- 4.05% for SCM culture. However, the cloning efficiency of BM-MSCs cultured in CDSFM was significantly lower than that in SCM (P<0.01). The expanded BM-MSCs in CDSFM preserved differentiation potentials into mesenchymal lineages in vitro, including adipocytes and osteoblasts. We have designed a chemically-defined serum free medium that could support in vitro proliferation and maintain the properties of BM-MSCs as stem cells, which could be applied to cell-based therapy and biomedical research.

To study the genetic basis of spontaneous transformation of mesenchymal stem cells (MSCs) and clinical application value MSCs were isolated by combining utilization of density gradient centrifugation and adherence screening. After cell homogeneity analysis by flow cytometry, spontaneous transformation MSCs were isolated after six-month in vitro expansion. Then cell total RNA was obtained with Trizol reagent and studied for gene expression profile. Differentially expressed genes between normal MSCs and spontaneous transformation MSCs in cDNA microarray were determined by real-time RT-PCR for validation of the microarray data. Forty-four genes were differentially expressed after spontaneous transformation of MSCs, among which 21 were up-regulated and 23 down-regulated. The result of real-time RT-PCR was in accordance with that of the cDNA microarray. Several genes in SHH, Notch, TGF beta/BMPs signal pathway play an important role in spontaneous transformation of MSCs.

To establish a two-dimensional biological printing technique of hBMSCs so as to control the cell transfer process and keep cell viability after printing.

To investigate the feasibility and effect of inducing adipose-derived stem cells (ADSCs) treated with growth differentiation factor 5 (GDF-5) to undergo chondrogenic differentiation in vitro.

To observe the effect of You Gui Yin and MSCs interventional therapy on the early stage of avascular necrosis of the femoral head (ANFH) and its role of improving revascularization and reossification.