To explore the in vitro methods of isolation and culture of human fetal epidermal stem cells (HFESCs) and the feasibility of the cultured cells as the target cells for gene transfection.

To investigate the different location and the expression characteristics of epidermal stem cells in normal adult skin and scar tissue.

To isolate and culture the murine fetal epidermal stem cells (ESCs) and folliculus pili cells (FPCs) in vitro, and to observe the regeneration of hair follicle and epidermis after cografting of ESCs and FPCs.

The present study identified the favorable environment conditions for Spermatogomial stem cells in vitro according to their unique biological properties. Three growth factors, stem cell factor (SCF), leukemia inhibitory factor (LIF) and basic fibroblast growth factor (bFGF) were all found to independently contribute to the proliferation of mouse spermatogonial stem cell. The percentage of cell proliferation significantly enhanced by SCF at 30 ng/mL but decreased with heightening its combination after cultured 120 hours. The mice spermatogonial stem cells were significantly proliferated after 120 hours' culture with 10 ng/mL and 20 ng/mL (P < 0.01) of LIF, between 20 ng/mL and 50 ng/mL (P < 0.01) for bFGF. SCF and bFGF were significantly enhanced mice spermatogonial stem cells proliferation after these three factors combination. For LIF, no obvious effect was observed.

A new method for establishing ES cell lines from 129/ter. C57BL/6J mice was set up which was characterized by the murine embryonic fibroblast cell(MEF) feeder, the medium of rat heart cell-conditioned medium(RH-CM) for ES cells, and the consecutive digestion by the digestion liquid containing 1% serum. Every group of improved experiments was done with a control of routine method. The results showed that, compared with routine method, the improved way increased the ratio of ES cell lines of 129/ter mice from 11.8% to 33.3%, and of C57BL/6J from 3.7% to 13.3%. The difference is distinct. The passage culture of ES cells showed that, compared with medium added LIF, RH-CM not only inhibited the differentiation of murine ES cells, maintained its dipoild karyotype, but also promote its adherence growth. This kind of culture condition not only maintained the ES cells in an undifferentiated state and their normal dipoild karyotype, but also a series of other characteristics of totipotent embryonic stem cells during extended culture period.

To establish a high sensitive and specific method of interphase fluorescence in situ hybridization (IFISH) to detect the low-frequency human cells in human/goat xenogeneic models.

To explore the effects of swine bone marrow derived mesenchymal stem cells (MSC) on the repair of skin wound combined local irradiation injury and theirs mechanism.

To explore the differences of phenotype and biological characteristics between fetal and adult bone marrow derived mesenchymal stem cells.

To identify the human hematopoietic stem cells from the human/goat xenogeneic model with molecular techniques.

Allogeneic hematopoietic stem cell transplantation is the only curative therapy for severe beta-thalassemia. This time, the experience of utilizing HLA 2-loci mismatched sibling cord blood transplantation (CBT) in a child with severe beta-thalassemia was firstly reported in our country. A 3-year-male patient had been diagnosed with severe beta-thalassemia at 6 months of age (HbF 86.6%, HbA1 1.7%, HbA2 1.7%, beta globin gene mutation CD17, A-->T/IVS-II-654, C-->T). The patient's HLA typing was A 24,11, B 58,35 and DRB1 03,15. During a subsequent maternal pregnancy. The prenatal diagnosis for thalassemia and prenatal HLA typing analysis were performed on 18 weeks of pregnancy. The results indicated that the male fetus was a heterozygote (beta globin gene mutation N/CD17, A-->T), HLA typing was A 24,11, B 58,51 and DRB1 03,12. 120 ml cord blood was collected at time of delivery, the total numbers of nucleated cells, CFU-GM and CD34(+) cells were 1.830 x 10(9), 16.653 x 10(5) and 3.11 x 10(6), respectively. A new conditioning regimen including: hypertransfusion, continuous i.v. desferrioxamine, busulfan, cyclophosphamide, antithymocyte globulin plus hydroxyurea and fludarabine. GVHD prophylaxis comprised cyclosporin A and mycophenolate mofetil. The viability of cord blood at the time infusion was 92%, The total numbers of nucleated cells, CFU-GM and CD34(+) cells in the transfused cord blood were 12.06 x 10(7)/kg, 1.098 x 10(5)/kg, and 2.04 x 10(6)/kg, respectively. Results showed that the patient's clinical course after cord blood transplantation was unremarkable. Acute GVHD grade I developed on day 15, methylprednisolone 2 mg/kg was given to cure. Neutrophil engraftment (ANC > 0.5 x 10(9)/L) on day 17, platelet engraftment (> 50 x 10(9)/L) on day 50. The patients became independent from red blood cell transfusion since day 80 (when his hemoglobin level kept > 12.5 g/L). His beta globin gene mutation and HLA typing were all the same as the donor's analyzed on day 60 and 200. There was also a switch in blood group from A pre-transplant to O post-transplant. It is concluded that the new conditioning and GVHD prophylaxis regimens allow a successful engraftment in this case. This observation may contribute in developing UCBT as an alternative when matched sibling donors are not available.

The purpose of this study was to evaluate the effects of cellular immunity activation on P58(+) cells expressing killer cell inhibitory receptor (KIR) and their regulatory function on cellular immunity, and provid theoretical data for preventing graft-vers-host disease (GVHD) in stem cell transplantation therapy. The mononuclear cells from human peripheral blood were incubated with IL-2, Con A and Lipostin (LP) for 72 hours. The KIR expressing cells, P58.1(+) and P58.2(+) cells, were analyzed by flow cytometry. The results showed that the percentages of CD3(+), CD4(+), CD8(+), CD16(+)CD56(+), P58.1(+) and P58.2(+) cells were greatly increased after treated with IL-2, Con A and LP, separately or in combination, and the percentages of above cells in combined treatment groups were higher than those of single stimulated groups, especially the percentage of cells in the IL-2 + LP group was significantly higher than those in IL-2 and LP singly treated groups.

There is a hypothesis that paroxysmal nocturnal hemoglobinuria (PNH) hematopoitic stem cells are resistant to the cytotoxic effect of T cells because they lack glycosylphosphatidylinositol (GPI)-linked proteins. The aim of this study is to investigate proliferation and anti-tumor activity of lymphocytes in patients with PNH, and also to assay the effect on normal cell (CD59(+)) phenotype in bone marrow of PNH patient by autologous lymphocytes in vitro. MTT assay for detection of lymphocytes proliferation and its anti-tumor effect was driven to delineate T cell reactive function. The CD34(-) and CD34(+) bone marrow cells (selected by means of immunomagnetic method) as well as unsorted marrow cells in PNH patients were cultured together with autologous CD59(+) or CD59(-) lymphocytes, their cultured supernatant, extrinsic IFN-gamma and IL-2 in a liquid culture system. CD59(+) cells were counted by flow cytometry after 10 day culture in vitro. The results showed that there were no differences in the proliferation ability of lymphocytes between each group: controls 1.42 +/- 0.46, unsorted PNH lymphocytes 1.40 +/- 0.35, CD59(-) 1.30 +/- 0.40, and CD59(+) PNH lymphocytes 1.40 +/- 0.42. Anti-tumor effect of lymphocytes declined in PNH patients when compared with control [(50.00 +/- 28.67)% vs. (76.13 +/- 10.15)%]. The proportion of CD59(+) cells diminished significantly after culture with autologous lymphocytes, their supernatant, extrinsic IFN-gamma or IL-2 (P < 0.01) in groups of unsorted, CD34(+) and CD34(-) bone marrow cells. No significant difference was found between groups of CD59(-) and CD59(+) lymphocytes, or CD34(-) and CD34(+) marrow cells. It is concluded that turbulences of immune regulations may be involved in pathogenesis of PNH.

Adult human bone marrow-derived mesenchymal stem cells (MSCs) were cultured on microcarriers in spinner flasks and were compared with those in conventional culture in 12-well plates. For the production of adherently growing MSCs, macroporous CultiSpher G gelatin microcarriers were used in concentration of 1 g/L. The cells were seeded in a density of 5 x 10(4) cells/ml in both spinner culture and conventional stationary culture. The result showed that after 7 days of cultivation a maximum viable cell concentration of 5.15 x 10(5) cells/ml was obtained in spinner culture. Whereas the cell density increased to a maximum of 1.675 x 10(5) cells/ml on day 5 in conventional stationary culture. Lactate was produced up to 12.06 mmol/L in spinner culture and up to 13.10 mmol/L in stationary culture, and glucose was consumed up to 7.38 mmol/L and 5.37 mmol/L respectively. The average lactate yield on glucose consumption in spinner culture was only 1.63, lower than that in stationary culture 2.44. This indicated that the energy metabolism in spinner culture was significantly more efficient than that in conventional culture. After spinner culture for 12 days, the MSCs maintain the characteristics of stem cells. It is concluded that the microcarrier culture system is a suitable way to expand the seeding cells for tissue engineering.

To study the effect of mesenchymal stem cell (MSC) on immune function, MSCs were isolated and cultured from human bone marrow cells. The purity of MSCs were identified with the spindle-fibroblastic morphology characterization by microphotograph and the phenotypes were tested by flow cytometry. MSCs were plated in 96-well plates (2,000/well and 1,000/well), and cocultured for 3 days with T cells isolated from cord blood. Cord blood T cells non-cocultured with MSC acted as control group. After cord blood T cells stimulated by PHA for 60 hours, [(3)H]-thymidine was added to each well and T cell proliferation was assessed by [(3)H] thymidine incorporation. The results showed that cord blood T cell proliferation was suppressed when 2,000 MSCs were plated each well and cord blood T cell proliferation was activated when 1,000 MSCs were plated. Our results suggested that the immunomodulatory function of MSC seemed dependent on cell dose. High concentration of MSC most often resulted in inhibition, while low concentration resulted in stimulation.

Embryonic hematopoiesis in mammals is characterized by successive temporal and spatial changes. Previous investigations indicate that in vitro differentiation of embryonic stem cells (ES cells) derived from 129 mice can mimic embryonic hematopoiesis to some extent. To investigate the in vitro hematopoietic differentiation capacity of ES cells derived from C57BL/6 mice, the authors initially established the murine ES cell line with standard identification methods employed. Next, two-step culture system was utilized for embryoid bodies formation and the appearance of different hematopoietic precursors was confirmed by CFC assay, cellular chemical staining as well as RT-PCR. The results demonstrated that the ES cell line MES-1 fulfilled the criteria of ES cell line and its progeny after in vitro differentiation included primitive and definitive erythrocyte precursors, mixed colony-forming cells and granulocyte/macrophage colony-forming cells. RT-PCR analysis revealed the molecular consistence of transcription factors and hematopoietic markers with cellular event. In conclusion, MES-1 established from C57BL/6 mice was able to differentiate in vitro to a variety of hematopoietic precursors, thus could partly recapitulate embryonic hematopoiesis.

To compare the different effects of the programmable cell freezer and the -70 degrees C mechanical freezer in the preservation of the combilical cord blood and to study the effects of magnetic activated cell sorting on cell biologic characters.

To establish a highly efficient method for the separation of adhering cell colonies.

To develop an efficient, rapid and reliable method for sex determination in preimplantation genetic diagnosis.

To explore the significance of AC(133) antigen expression on cord blood (CB) hematopoietic cells.

Neurotrophic factors includes nerve growth factors (NGF) family, glial cell line-derived neurotrophic factors (GDNF) family and other neurotrophic factors. NGF, BDNF, NT-3, NT-4/5 and NT-6 constitute NGF family (the neurotrophins), which may enhance both survival and differentiation of neurons from the EGF-responsive hippocampal and the subventricular zone neural stem cells. GDNF family includes GDNF, NTN, PSP and ART, whose major role is in peripheral neurodevelopment. This family enhance proliferation and survival of enteric neural crest precursor cells and is critical for the development of peripheral sensory nerve. Other growth factors such as bFGF and EGF can enhance proliferation and survival of neural stem cell. CNTF and LIF are critical for differentiation of neural stem cells.