The objective of this study was to investigate the specificity of detecting the phosphotyrosine level with anti-phosphotyrosine monoclonal antibody PY20 for diagnosis and prognosis of patients with chronic myeloid leukemia (CML) and the possibility of its clinical application. The positive rate of PY20 in 28 newly diagnosed CML patients was detected by flow cytometry using anti-PY20 antibody, the bcr-abl fusion gene was detected by nested RT-PCR, the Ph chromosome was measured by R-banding cytogenetic analysis, and the coincidence of PY20 positive rate with results of bcr-abl fusion gene and Ph chromosome detection was compared. In addition, the positive rate of PY20, the changes of bcr-abl fusion gene and Ph chromosome were determined in follow up 7 CML patients after allo-hematopoietic stem cell transplantation. The results indicated that the positive rates of PY20 in 28 newly diagnosed CML patients in groups of chronic phase (CP), accelerated phase (AP), and blast phase (BP) were (40.31% +/- 1.22)%, (77.28 +/- 1.14)% and (78.12 +/- 1.32)% respectively. The positive rate of PY20 in CP was lower than that in AP and BP (p < 0.05). There was no difference in positive rate of PY20 between AP and BP (p > 0.05). PY20 expression level of leukocytes from peripheral blood and bone marrow showed no difference (p < 0.05). The positive rates of PY20 in patients with CR, PR and NR were (15.56% +/- 1.51)%, (38.73% +/- 2.31)% and (60.43% +/- 2.04)% respectively. The positive and negative coincidence between PY20 and RT-PCR was 92.31% and 95.45% respectively. The positive and negative coincidence between PY20 and Ph Chromosome in newly diagnosed patients was 88.46% and 95.46% respectively. Ph chromosome and PY20 were all negative in 7 CML patients after allo-HSCT. Bcr-abl fusion gene was negative persistently in 5 patients, but in the other 2 patients, the fusion gene was persistently positive. In conclusion, the detection of the level of phosphotyrosine in CML cells has high sensitivity and specificity. The results of PY20 cell positive rate combined with detection of bcr/abl fusion gene and Ph chromosome might be useful in diagnosis as a good index of monitoring.

This study was purposed to compare the significance of multiplex short tandem repeat polymerase chain reaction (STR-PCR) and fluorescent in situ hybridization (FISH) for monitoring chimerism after sex-mismatched allogeneic hematopoietic stem cell transplantation (allo-HSCT). The chimerism of bone marrow or peripheral blood cells from 38 patients was analyzed by STR-PCR and FISH on days 14, 28 and at 3 months after allo-HSCT. The results indicated that on day 14, the complete chimerism (CC) was detected in 14 of 30 cases by STR-PCR and in 8 of 30 cases by FISH (p > 0.05). On day 28, the CC was detected in 26 of 31 cases by STR-PCR and in 15 of 31 cases by FISH (p < 0.01). At 3 months, the CC was observed in 22 of 24 cases by STR-PCR and 17 of 24 cases by FISH (p > 0.05). 14 cases were found to have a graft rejection or relapse among 28 cases which were continuously monitored more than 3 months post the transplants. Donor cell decrease in 9 of 14 cases was proved by FISH alone. It is concluded that FISH is more sensitive than STR-PCR in early monitoring chimerism status of post-transplant and in predicting graft rejection or disease relapse.

The purpose of this study was to explore the effect of intra-bone marrow infusion (iBMI) of cord blood (CB)-derived hematopoietic stem/progenitor cells (HS/PCs) on human hematopoietic reconstitution in xenotransplanted NOD-SCID mouse model. Aliquots containing 5 x 10(5) CB CD34(+) cells were transplanted into sublethally irradiated NOD-SCID mouse via intravenous infusion (iVI) or iBMI routes. 64 female NOD-SCID mice were divided randomly into 3 groups: iBMI group, iVI group and negative control group. The engraftment levels of human hematopoietic cells at 3, 5 and 8 weeks after xenotransplantation were detected by fluorescence-activated cell sorter (FACS), polymerase chain reaction (PCR), immunohistochemistry and HPC colony formation assay, and long-term hematopoietic reconstitution capacity of HSC was tested by secondary transplantation. The results showed that the percentages of human CD45(+) cells in bone marrow, peripheral blood and spleen of recipient in iBMI group at 8 weeks after xenotransplantation were significantly higher than those in iVI group (p < 0.05). HS/PCs given through both iVI and iBMI methods had the ability of multilineage differentiation, the percentages of CD45(+)CD19(+) cells, CD45(+)CD33(+) cells, CD45(+)CD56(+) cells and CD45(+)CD34(+) cells of recipient bone marrow in iBMI group at 8 weeks after xenotransplantation were significantly higher than those in iVI group (p < 0.05), while other lineages in iBMI group were also higher than that in iVI group (p > 0.05). alpha-satellite-specific fragment of human chromosome 17 could be detected by PCR in liver, spleen, lung, peripheral blood and bone marrow cells of long-term survival recipients in both iVI and iBMI groups. Human CD45 antigen could be detected by immunohistochemical method in spleen, liver and lung of recipients in iBMI group at 8 weeks after xenotransplantation. Total colony count in iBMI group at 8 weeks after xenotransplantation was significantly higher than that in iVI group (p < 0.05). alpha-satellite-specific fragment of human chromosome 17 could be detected in all above organs of both group recipients at 6 weeks after secondary xenotransplantation. It is concluded that iBMI of CB CD34(+) cells improves hematopoietic reconstitution in xenotransplanted NOD-SCID mouse model.

The mechanisms of human bone marrow mesenchymal stem cells (hBMMSCs)-mediated immunomodulation are still not be completely clarified. In order to investigate the expression of B7-H1 on hBMMSCs and to explore whether B7-H1 mediated signaling pathway (B7-H1/PD-1) involves in the mechanisms of hBMMSCs-mediated immunomodulation, the hBMMSCs were isolated, cultured and identified, the B7-H1 expression on hBMMSCs was detected by flow cytometry, RT-PCR, and Western blot. The inhibitory effect of hBMMSCs on proliferation of T lymphocytes was observed in mixed lymphocyte culture, and then the functional anti-B7-H1 monoclonal antibody (mcAb) was used to block B7-H1, the proliferation of T lymphocytes was detected by using CCK-8. The results indicated that hBMMSCs highly expressed B7-H1 molecule, hBMMSCs effectively inhibited the proliferation of T lymphocytes with a dose-dependent manner, and the inhibitory proliferation of T lymphocytes by hBMMSCs could be partially restored when the anti-B7-H1 mAb was used to block the B7-H1, the inhibitory rate of T lymphocyte proliferation decreased from 64.1% to 38.75%. It is concluded that B7-H1 highly expresses on hBMMSCs, the B7-H1 mediated signaling pathway (B7-H1/PD-1) involves in the mechanisms for hBMMSCs-mediated immunomodulation.

This study was purposed to investigate the angiogenesis-promoting activities of human mesenchymal stem cells (hMSCs) modified by hepatocyte growth factor (HGF) and the underlying mechanisms. The hMSCs were transfected by recombinant adenoviral vector carrying human HGF gene and seeded onto the chicken chorioallantoic membrane. Three days later, the number of blood vessels was counted and their angiogenic response was compared with those of hMSCs of same generation, recombinant basic fibroblast growth factor (bFGF) and alpha-MEM as control. The expression levels of bFGF, VEGF, angiopoietin-1 and angiopoietin-2 were evaluated by RT-PCR assay. The results showed that gene-modified hMSCs exhibited greatest activity to promote angiogenesis while the angiogenic response was nearly same between groups treated by hMSCs and bFGF, all of which were significantly higher than that observed in control (p < 0.01). RT-PCR analysis revealed that hMSCs constitutively expressed multiple angiogenesis-associated growth factors and their levels seemed up-regulated by HGF gene transfer. It is concluded that HGF gene-modified hMSCs show a potent angiogenesis-promoting function and may be useful in the treatment of ischemic disorders.

This study was purposed to clarify whether biology function of mesenchymal stem cells (MSCs) is changed by suppressing the development of dendritic cells (DC) derived from hematopoietic stem cells (HSCs). MSCs were cocultured with dendritic cells derived from CD34 positive hematopoietic stem cells (HSCs), and then the expression of cytokines and phenotypes of DCs/MSCs were detected by RT-PCR and flow cytometry respectively. Induced experiments were used to analyze the differentiation ability of MSCs. The results showed that DCs/MSCs were negative for the CD14, CD34, CD45, CD31, CD86, but positive for HLA-ABC, CD29, CD73, though the percentage decreased as MSCs vs DCs/MSCs (93.1% vs 13.44%, 98.3% vs 78.8%, 95.3% vs 75.9%). In addition, the expression of cytokines such as M-CSF, TGF-beta increased in DCs/MSCs. After differentiation induction, DCs/MSCs were deprived of the potential to differentiate into adipocytes, but maintained osteogenesis characteristics. It is concluded that the basic characteristics of MSCs are altered after coculture with DCs, and DCs/MSCs result in lower expression of mesenchymal phenotypes and decrease differentiation ability, but increase the expression of cytokines related to hematopoiesis and immunity.

This study was purposed to investigate the influence of inflammatory microenvironment on mesenchymal stem cells (MSCs) and regulatory effect of MSCs on osteoblast formation. The MSCs were isolated from synovial fluid of patients with rheumatoid arthritis (RASF-MSCs) and were cultured, the immunotypes of RASF-MSCs were detected by flow cytometry, the ability to differentiate RASF-MSCs into osteoblasts and adipocytes was determined by means of osteogenic and adipogenic induction, the regulatory effect of RASF-MSCs on osteoblast formation was assayed by co-culturing RASF-MSCs whth CD14(+) monocytes and in situ tartrate-resistant acid phosphatase staining. The results showed that RASF-MSCs highly expressed CD105, CD73, CD29, CD44, CD166 and HLA-ABC. Meanwhile, they lowly expressed CD34, CD45, CD31, HLA-DR, CD80 and CD86. However, RASF-MSCs decreased multi-differentiation capability as compared with BM-MSCs. More interestingly, RASF-MSC significantly promoted osteoclasts formation (p < 0.05) when co-cultured with monocytes. It is concluded that MSCs from rheumatoid arthritis synovial fluid exert typical MSC phenotypes but displayed decline of multi-differentiation capability. RASF-MSCs especially show promoting effect on osteoclastogenesis. The findings of this study may contribute to the understanding biological behavior of MSCs in pathological microenvironment.

This study was aimed to investigate the effect of activated T cell on the ability of MSC to differentiate into osteoblasts. The activated T cells with MSCs were co-culture for 14 days, then the osteoblast formation was tested by alkaline phosphatase staining. Furthermore, the supernatant of activated T cell was added in culture system of MSCs, the expression of molecules related with immune regulation of activated T cells was detected by RT-PCR, so as to determine what kinds of cytokine displayed the important function in MSC differentiation. The result showed that activated T cell could promote differentiation of MSC into osteoblasts, and IL-1beta played an important role in the effect of activated T cells on MSCs, while TNF-alpha, TGF-beta1 were not. It is concluded that the activated T cells promote the differentiation of MSCs to osteoblasts. The interactive influence between MSCs and immune cells can be mediated through cytokines.

The present study was designed to culture and purify high proliferative potential endothelial progenitor cells (HPP-EPCs) from murine bone marrow and their progeny cells using a culture system which has been established by us recently, in order for more intensive researches on these cells. Fresh murine bone marrow cells were preplated to allow the preferential attachment of non-EPCs to tissue culture plates and then unattached cells were repreplated in the culture system containing the bone marrow endothelial cell line-conditioned medium (BMEC-CM). The colonies containing about 2 x 10(4) cells were collected respectively and single colony-derived cells were cultured for their expansion in the above-mentioned culture system. These single colonies were able to yield 8 x 10(6) progeny cells. The endothelial-lineage characteristics of expanded cells were confirmed by immunofluorescent staining for CD31 and vWF, FITC-UEA-1 binding and Dil-Ac-LDL uptake. These data suggest that murine bone marrow HPP-EPCs can proliferate exuberantly so that their progeny cells can be obtained with high yield by using the single colony-derived cell culture in the presence of BMEC-CM.

4 ng/ml bFGF is indispensable for hESC cultured on mouse embryonic fibroblasts (MEF), withdrawal of bFGF drives the hESC to differentiate. In order to exploit effect of bFGF on MEF, we collected a series of MEF conditioned medium (bFGF-MCM) by co-culturing MEF with increasing bFGF concentrations: 0.03, 0.1, 0.3, 1 and 4 ng/ml. The primitivity of hESC cultured in bFGF-MCM was estimated by morphology and alkaline phosphatase staining. Compared with the control medium (medium conditioned without bFGF: MCM), percentage of undifferentiated colony was increased from 23% to 29%, 44%, 74%, 77% and 78%, respectively. However, percentage of undifferentiated colony in the blank medium (medium conditioned with bFGF but without MEF: bFGF-SR) was from 13% to 31%. This indicated that low concentration of bFGF acted on MEF and stimulated MEF producing effective conditioned medium for maintaining hESC. To identify active elements in the effective conditioned medium can help to understand mechanisms of hESC self-renewal.

To construct recombinant adeno-associated virus (rAAV) vector containing angiopoietin-1 (ANG-1) gene and to express the ANG-1 in targeting cells.

To observe the effect of electroacupuncture (EA) on peripheral blood endothelial progenitor cell (EPC) counts, vascular endothelial growth factor (VEGF) level and total nitric oxide synthase (TNOS) and inducible nitric oxide synthase (iNOS) activity in cerebral ischemia-reperfusion injury (CI/RI) rats.

The recurrence and metastasis of tumor are the main reasons for the failure in malignant tumor treatments, searching for the best target to prevent the tumor recurrence and metastasis is the focus of tumor research. Research showed that tumor stem cells are the vital factor of malignant tumor recurrence and metastasis, there is no method of target regulating the function of tumor stem cells now. Traditional Chinese Medicine have played a good role in preventing tumor recurrence and metastasis according to the previous studies, so we can suppose that tumor stem cells may be the final target of TCM in preventing tumor recurrence and metastasis. To expand the effect and study the mechanism of action we should introduce the tumor stem cells into the study of TCM in treating malignant tumor.

To observe whether Naomai Yihao (NM) Capsule, a compound traditional Chinese herbal medicine for regulating the "sea of blood in brain", and bone marrow stromal stem cell (BMSC) transplantation could improve angiogenesis in focal cerebral ischemia in rats.

To observe the differentiation of bone mesenchymal stem cells (BMSCs) co-cultured with purified sinoatrial node cells (SNC) of neonate rats.

Adult stem cells are drawing more and more attention due to the potential application in degenerative medicine without posing any moral problem. There is growing evidence showing that the human amnion contains various types of adult stem cell. Since amniotic tissue is readily available, it has the potential to be an important source of regenerative medicine material. In this study we tried to find multipotent adult stem cells in human amnion. We isolated stem cells from amniotic mesenchymal cells by limiting dilution assay. Similar to bone marrow derived mesenchymal stem cells, these cells displayed a fibroblast like appearance. They were positive for CD105, CD29, CD44, negative for haematopoietic (GlyA, CD31, CD34, CD45) and epithelial cell (pan-CK) markers. These stem cells had the potential to differentiate not only into osteogenic, adipogenic and endothelial lineages, but also hepatocyte-like cells and neural cells at the single-cell level depending on the culture conditions. They had the capacity for self-renewal and multilineage differentiation even after being expanded for more than 30 population doublings in vitro. So they may be an ideal stem cell source for inherited or degenerative diseases treatment.

Numerous studies and clinical trials have demonstrated the efficacy of recombinant adeno-associated virus gene delivery vectors. However, prior to expression, it is necessary to convert the single-stranded DNA genome into double-stranded DNA, which hinders the efficiency of these vectors. We can entirely circumvent this step through the use of self-complementary recombinant adeno-associated virus vector (scrAAV). ScrAAV packages an inverted repeat genome that can fold into double-stranded DNA without the requirement for DNA synthesis or base-pairing between multiple vector genomes. By using scrAAV, we could increase expression efficiency and reduce immune response caused by vectors themselves. Therefore, it is a promising vector for gene therapy. So far, it has been used in the treatment of hepatic diseases, central nervous system diseases, and eye diseases. It has also been used in the modifications of stem cells and as vectors for siRNA/miRNA and ribozymes. In this review, we focused on the preparation, expression and location of scrAAV both in vitro and in vivo. We mainly introduced the recent progress of scrAAV based therapy of Hemophilia B, in order to elucidate the potential and prospects of scrAAV in gene therapy.

To introduce the research of nucleus pulposus cells for treating intervertebral disc degeneration.

To explore the labeling efficiency and cellular viability of rabbit BMSCs labeled with different concentrations of superparamagnetic iron oxide (SPIO) particles, and to determine the feasibility of magnetically labeled stem cells with MR imaging.

To evaluate the effect of copper-ion on the proliferation and differentiation of human umbilical vein endothelial cell (HUVEC).