To set up a stable technology for the growth of yolk sac CFU-GM.

To investigate the effect of "two-phase" tissue engineered cartilage constructed by autologous marrow mesenchymal stem cells(MSCs) and allogeneic bone matrix gelatin(BMG) in repairing articular cartilage defects.

To study the culture and purification of the fetal mouse liver mesenchymal stem cells (MSCs) in vitro and to investigate their differentiation potential and the composite ability with true bone ceramic(TBC).

To establish a method of isolating and culturing adult human blood-derived stem cells(MSCs) and to investigate their osteogenic potential in vitro.

To evaluate the host immune reaction against adenovirus mediated human bone morphogenetic protein 2 (Adv-hBMP-2) gene therapy in repair of tibial defects.

Myelodysplastic syndromes are refered to as a group of diseases characterized by abnormal clonal proliferation of hematopoietic stem cells with pancytopenia and dysplasia. Recently, it has been documented that ringed sideroblasts are not only confined to the refractory anemia with ring sideroblast (RARS) subtype of MDS, but also contribute to numerous underlying MDS pathophysiological processes as a significant feature of dysplasia. This clonal heterogeneity suggested a pathogenetic role of mitochondrial DNA mutation. Many studies have shown that mitochondrial respiratory chain defects resulting from mutation of mitochondrial DNA may lead to multiple pathophysiologic changes, and may impact on the pathogeneses of MDS.

Monitoring engraftment of donor cells after allogeneic transplantation is the key of assessing successful establishment of animal transplantation model. The purpose of this study was to establish a method for analysis of chimerism in rhesus transplantation model. Y-specific sequence in rhesus was amplified by the polymerase chain reaction (PCR), method for analysis of chimerism in rhesus after sex-mismatched transplantation was established; the feasibility and sensitivity of the approach were tested by using serial DNA mixtures of sex-mismatched individuals; the accuracy of results was confirmed by chromosome karyotype analysis simultaneously; Chimerisms of one rhesus received allogeneic stem cell transplantation and the other received mesenchymal stem cells (MSC) transfusion were detected by this method. The results showed that a 176 bp long sequence of PCR product was gained in male rhesus, while no product was gained in female rhesus. The sensitivity of this method was up to 0.05% (male/female DNA ratio). Male donor chimerism were found on day 7 and 14 after allogeneic stem cell transplantation by Y-specific sequence and chromosome karyotype analysis. Otherwise, male donor chimerism was found in peripheral blood at 1 hour and in bone marrow on day 30 after MSC transfusion by this method, but no male donor chimerism was found after MSC transfusion using chromosome karyotype analysis. In conclusion, this rapid, sensitive approach can used to assess chimerism in experiments of rhesus alloorgan transplantation and cell transfusion.

To study if rhesus haploidentical hematopoietic stem cell transplantation model can be established by non-myeloablative conditioning, parent monkeys were used as donors, offspring monkeys were used as recipients. The recipient monkeys received a nonmyeloablative conditioning consisting of fludarabine, cyclophosphamide, total body irradiation and rabbit anti-human thymocyte globulin. Cyclosporine, mycophenolate mofetil and anti CD25 antibody were used for GVHD prevention. Donor mobilized peripheral blood stem cells were transplantated on day 0. Hematopoietic recovery, chimerism level, GVHD were assessed regularly. The results indicated that hematopoietic recoveries in all 4 cases were observed within 8 days after transplantation. Donor hematopoietic chimerism could be induced in all cases, chimerism analysis showed full donor chimerism (FDC) in case 3 and 4, and II to III grade GVHD developed on day 12 and 14. In case 1, only low level donor chimerism was detected on day 7, and transplantation rejection happened eventually. Unfortunately, kidney failure happened in case 2 after conditioning and died several days later, chimerism analysis showed 50% donor rate on day 7. It is concluded that the rhesus transplantation model was successfully established by nonmyeloablative conditioning for striding over the MHC barrier. This rhesus monkey model would provide a basis for future research.

This study was aimed to explore the feasibility of transplanting human cord blood stem cells (HSC) into pre-immune fetal and neonatal pigs, and to investigate the self-renewal of HSC in the recipient pigs. The fetus and neonate were manipulated in sterile separated room and human donor cells were injected into fetus via fetus muscle or umbilical vein (dissectted womb) or into neonate via umbilical vein before cutting it. Human CD45(+) cells s were detected by labeling with human anti-CD45 antibody and analyzed by fluorescence activated cell sorting (FACS). The results showed that tested pigs developed as well as control and a definite proportion of human cells existed in peripheral blood of chimeric pig on day 60 after transplantation. In conclusion, the fetus and neonate pigs can tolerate a definite proportion of human antigens, and to establish the human/pig model of hematopoietic chimerism is possible.

TGF-beta, as an inhibitor of hemopoiesis, excreted by hematopoietic stem and progenitor cells, down-regulates the expression of cytokines such as Flt-3 ligand, SCF, IL-3 etc on the stem and progenitor cells. The effect of anti-TGF-beta antibody on ex vivo expansion and expression of adhesive molecules on cord blood CD34(+) cells was studied in this research. The CD34(+) cells from six units of fresh umbilical cord blood were enriched by density gradient sedimentation and purified by miniMACS cell isolation system, and plated them into the SFEM serum free culture system which containing SCF, Flt-3L, TPO and IL-3 in the condition of 37 degrees C, 5% CO2, and saturated moisture. There were three groups in this experiment: (1) blank group: same as the culture system described above; (2) control group: added with normal rabbit IgG into the mentioned culture system; (3) test group: the same culture system with anti-TGF-beta1 antibo-dy. Cultured for 6 days, the number of mononuclear cells (MNC) was counted, the expression of CD34 antigen, CD117 (c-kit) antigen, CD11a antigen, CD49d antigen and CD33 antigen was tested with FCM. Meanwhile, cells of the three groups were plated in the methylcellulose culture system for 14 days, the number of CFU-GEMM, BFU-E, CFU-GM was counted. The results indicated that the expansion multiples of MNC, CD34(+) cells, CD34(+)c-kit(+) cells, CFU-GEMM in the test group (41.82 +/- 13.49, 15.62 +/- 6.95, 13.36 +/- 6.12, 11.07 +/- 4.05) were significantly higher than in the control group (28.86 +/- 9.03, 10.40 +/- 4.98, 9.04 +/- 4.40, 6.36 +/- 2.37) (P = 0.001, 0.002, 0.003, 0.002) respectively. The expansion multiple of more primitive CD34(+)c-kit(-) subpopulation in the test group (69.10 +/- 41.06) was even higher than in the control group (27.29 +/- 10.40) (P = 0.024). Adhesion molecule expression on the CD34(+) cells after short-term expansion: the expression of CD11a on the CD34(+) cells of the original cord blood was (61.73 +/- 4.13)%, and CD49d was (55.12 +/- 5.22)%. After expansion in each group the expression of CD11a on the CD34(+) cells did not change with statistical significance (P > 0.05), the expression of CD49d increased (P < 0.05). Compared with blank group and control group, anti-TGF-beta antibody did not impact on the expression of CD11a and CD49d (P > 0.05). It is concluded that anti-TGF-beta antibody can synergize other cytokines to effectively enhance the proliferation of cord blood NC, CD34(+) cells, progenitor subpopulation of CD34(+)c-kit(-) cells, and increase the output of more primitive progenitor colony, CFU-GEMM and BFU-E. At the same time, anti-TGF-beta antibody did not depresss the expression of adhesion molecules on CD34(+) cells.

This study was aimed to investigate the effect of various cytokines on megakeryocytes expansion in vitro from human cord blood CD34(+) cells in order to establish an optimal culture system for MK expansion. Mononuclear cells were obtained by Ficoll-Hapaque density gradient separation. CD34(+) cells were positively isolated using a CD34 progenitor cell isolation kit. CD34(+) cells were placed into 24 well plates at a concentration of 2 x 10(4) per well. Each well contained 1 ml of IMDM with the present of effective MK cells growth cytokines. Clonogenic potentials of MK progenitor were assayed using a methylcellulose cultures system. The results suggested that four cytokines (IL-3 + IL-6 + TPO + FLT3L) culture system could effectively induce and expand cord blood CD41(+) MK cells. The number of CD41(+) cells expanded 154.67 +/- 32.21-fold on day 7, and 193.23 +/- 25.24-fold on day 14. In conclusion, established expansion system in vitro for MK cells provides experimental foundation for recovery of platelets after cord blood transplantation.

Human mesenchymal stem cells (MSC) are one kind of adult stem cells that can self-renew and give rise to one or more mesenchymal tissues, existing in bone marrow and other tissues. Not similar to CD34 recognizing hematopoietic stem cells, no such marker can be used yet to identify MSC. To isolate and identify MSC from bone marrow, anti-SH2 and SH3 monoclonal antibodies as markers to identify MSC were used. Two monoclonal antibodies were purified from ascites of SH2 and SH3 hybridomas-inoculated mice, flow cytometry and immunohistochemistry were used to identify plastic-adherent cultured MSC. And SH2 and SH3 antigen positive cells were isolated from bone marrow mononuclear cells (BMMNC) by immunobeads covered with secondary antibodies. And anti-SH2 and CD105 McAbs were used to label MSC at the same time to clarify whether they recognize the same antigen. The results showed that about 80% of MSC were antigens SH3 and SH2 positive. The SH2 and SH3 positive-selected cells were MSC while MSC accounted for less than 1% of negative-selected cells. When cells were labeled by SH2 McAb, they could not be labeled by CD105 simutaneously. In conclusion, antigens SH2 and SH3 are specific markers to identify and isolate MSC. Anti-SH2 McAb can replace anti-CD105 McAb to identify the specific marker on MSC.

To investigate the immune regulatory effects of human bone marrow mesenchymal stem cells on alloantigen T lymphocyte in vitro, human MSCs were isolated and expanded from bone marrow cells, and identified with cell morphology, and the phenotypes were assessed by immunohistochemistry and flow cytometry. As the stimulation factor of T lymphocytes proliferation, either PHA or dendritic cells isolated from cord blood were cocultured with CD2(+) T lymphocytes from peripheral blood mononuclear cells by magnetic beads with or without MSC in 96-well plats for seven days. T cell proliferation was assessed by [(3)H]-thymidine incorporation using a liquid scintillation counter. T cell subsets, Th1, Th2, Tc1 and Tc2 were analyzed by flow cytometry after co-culture of CD2(+) T cells with MSCs for 10 days. The results showed that a significant decrease of CD2(+) T cell proliferation was evident when MSC were added back to T cells stimulated by DC or PHA, and an increase of Th2 and Tc2 subsets were observed after co-culture of MSC with T lymphocytes. It is suggested that allogeneic MSC can suppress T cell proliferation in vitro and the cause of that was partly depend on interaction of cells and the alteration of T cell subsets.

The purpose of this study was to evaluate the effecacy and safety of CHOEP mobilization regimen, and the effect and tolerance of sequential chemotherapy combined with tandem autotransplants of peripheral blood stem cells for aggressive lymphoma. The clinical data of 5 patients with recurrent, aggressive lymphoma treated with of sequential chemotherapy combined with tandem autotransplants were analyzed retrospectively. The patients included 1 HD and 4 NHL. Mobilization regimen was CHOEP combined with G-CSF 5 microg/(kg x d). The conditioning regimen for the tandem transplantation was high-dose CHOEP. The interval of the tandem autotransplantation was 9 (5 - 31) weeks. In tandem autotransplant, the cell number of MNC transfused was 3.05 (1.91 - 4.14) x 10(8)/kg and 3.55 (2.23 - 6.0) x 10(8)/kg; CD34(+) cells were 4.11 (2.59 - 4.94) x 10(6)/kg and 5.70 (2.77 - 10.6) x 10(6)/kg; CFU-GM was 2.96 (2.01 - 4.54) x 10(5)/kg and 2.44 (1.78 - 2.9) x 10(5)/kg respectively (P > 0.05). The results showed that all patients gained prompt and sustained hemotopoietic reconstitution. The interval of ANC >or= 0.5 x 10(9)/L was 10 (8 - 12) days and 10.5 (9 - 12) days; Pt >or= 2.0 x 10(9)/L was 11 (10 - 14) days and 12.5 (10 - 15) days respectively (P > 0.05). Four patients survived, three patients among them were alive in disease-free for median of 46 (9 - 88) months. The overall survival was 80%, and the disease-free survival was 60%. In conclusion, the method of sequential high-dose CHOEP chemotherapy combined with autotransplants of peripheral blood stem cells in tandem for aggressive lymphoma is probably safe and effective.

To determine the effect of naoyian (NYA) on the expression of phosph-Akt in neural stem cells injured with anoxia.

To study the homing capacity of allograft mesenchymal stem cells (MSCs) transfected with a green fluorescent protein (GFP) retroviral construct to the liver of rats.

Fibrosis is the common end stage of most liver diseases. Unfortunately, there is no effective treatment available currently. This study was designed to evaluate the effect of Flk1+ mesenchymal stem cells (MSC) from murine bone marrow (Flk1 + MSC) on fibrosis formation induced by carbon tetrachloride (CCl4). In this study Flk1+ MSC were isolated from bone marrow of male BALB/c mice. A CCl4 induced hepatic fibrosis model was used. Flk1+ MSC were systemically infused immediately or one week after the female mice were challenged with CCl4. Fibrosis index and donor cell engraftment were assessed two or five weeks after CCl4 challenge. We found that Flk1+ MSC transplantation immediately, but not one week after exposure to CCl4, significantly reduced CCl4-induced liver damage and collagen deposition. In addition, levels of hepatic hydroxyproline and serum fibrosis markers (HA, P-III-P) in mice receiving immediate Flk1+ MSC transplantation after CCl4 challenge were significantly lower compared to those of control mice. More importantly, histological examination suggested that hepatic damage recovery was much better in these immediately Flk1+ MSC-treated mice. Immunofluorescence, PCR, and fluorescence in situ hybridization (FISH) analysis revealed that donor cells engrafted into host liver, had epithelium-like morphology and expressed albumin (ALB), although at low frequency. In conclusion Flk1+ MSC might initiate endogenous hepatic tissue regeneration, engraft into host liver in response to CCl4 injury, and ameliorate its fibrogenic effects.

To investigate the possibility of establishing the human bone marrow mesenchymal stem cells (hMSCs) bank as to provide an alternative source for the seed cells of tissue engineering.

To establish a better method of isolating and culturing of neural stem cells (NSCs) in neonatal rat brain.

To study the auditory function and auditory nerve pathological changes of the experimental allergic neuritis (EAN) animal model in Guinea pigs.