Lectins, proteins that bind sugar moieties of glycolipids and glycoproteins, occur in all organisms and are especially abundant in many plants. Plant lectins probably have multiple roles related to their ability to act as recognition molecules. Here we present a review on the biological characterization of a new plant lectin in red kidney bean named Flt3 receptor-interacting lectin(FRIL), and focus on the mechanisms that FRIL can preserve quiescent hematopoietic stem cells in suspension culture.

To establish and stabilize a new HLA typing strategy, reference strand mediated conformation analysis (RSCA), and to conform its advantages by using HLA-A as target gene.

To investigate the effects of collagen I on the adhesion, proliferation, and differentiation of MSCs on PLGA.

To analyse the differentiation features of embryonic stem cells which were induced by the supernatant of retinal cells and retinoid acid (RA).

To investigate the probabilities of murine embryonic stem cells (ESC) differentiating into conjunctival epithelial cells and lay a basis for seeking a new source of seed cells provided in conjunctival tissue engineering.

To explore the critical dose of T lymphocyte for preserving graft versus leukemia (GVL) while preventing GVHD in murine acute leukemia model treated with H-2 haploidentical hematopoietic stem cell transplantation (HSCT).

To explore the category, quantity and clinical significance of autoantibodies on bone marrow hematopoietic cells in patients with immunorelated cytopenia and evaluate the sensitivity of direct antiglobulin reaction (Coombs test ) of bone marrow mononuclear cells (BMMNC).

Apoptosis is necessary for the development and maturation of Leydig cells. However, increased apoptosis results the decline of testosterone production, which may increase germ cell apoptosis and the possibility of infertility. There are several aspects contributing to Leydig cell apoptosis such as ethane dimethanesulphonate (EDS), glucocorticoid, developmental stage and some hormones including FSH, LH/hCG and testosterone. A number of genes are involved in the regulation of Leydig cells apoptosis. It was reported that SCF/c-kit, Bcl-2 and Bcl-xl inhibited the apoptosis while caspase-3, Fas, Bax and clusterine stimulated it.

To investigate the expression and significance of survivin protein and mRNA in cord blood (CB) CD(34)(+) stem/progenitor cells.

To study the recombinant human interleukin 11 (rhIL-11) in combination with granulocyte-colony stimulating factor (rhG-CSF) for mobilizing peripheral blood stem/progenitor cells in C57BL/6 mice.

To evaluate the clinical efficacy of mobilized autologous peripheral blood stem cells (PBSC) transplantation in a 48 years old patient with lower limb arteriosclerosis obliterans (ASO).

To study the characteristics of dermal mesenchymal stem cells (DMSC), and explore whether they could enhance hematopoiesis recovery in vivo as well as facilitate proliferation and differentiation of hematopoietic cells in vitro.

The development of reconstructed oocytes and the survival rate of cloned animal were affected by many factors during nuclear transfer. The genetic constitution and the genetic state of donor nucleus were proposed to be primary factors, which affected the survival rate of cloned animal. In addition, the survival rate of cloned animal might be influenced by nuclear transfer technique itself and passages of donor cells as well as the activation methods of oocytes. We reconstructed oocytes with outbreeding Kunming albino mouse ES cells and enucleated rabbit oocytes, and analyzed the effects of the passages of ES cells and 6-DMAP on the development of interspecific reconstructed oocytes. The interspecific reconstructed ES-rabbit oocytes were activated either by combined two set electric pulses and 6-DMAP or by two set electric pulses alone. The rate of cleavage was significantly higher for the group (86.2%) treated with 6-DMAP than the group (64.2%, P < 0.05) treated with electric pulses only, and the rate of blastocysts was 17.0% and 13.4% respectively, which were not significantly different between two groups. When ES cells that had been passed for 24 and 14 generations were used as donors, the cleavage rates of the reconstructed oocytes were 88.5% and 82.1%, respectively (P > 0.05), and the rates of blastolation were 16.7% and 15.4%, respectively (P > 0.05). The results show that 6-DMAP increases the cleavage rate of reconstructed oocytes derived from ES cells, and affects slightly the developmental rate of blastocysts. There are no differences when high passage and low passage ES cells are used as nuclear donors.

To evaluate the feasibility of using human embryonic fibroblast(HEF) as feeder layer in the culture of human embryonic stem(ES) cells in vitro, we investigated the morphology, the sensitivity to 0.25% trypsin, the growth curve and cell cycle of HEF with DMEM(low glucose) +10% FBS used as culture medium, and then we compared HEF with mouse embryonic fibroblast (MEF). The results showed that both HEF and MEF are adherent cells in vitro, and HEF has longer life span and better growth ability than MEF. In room temperature, HEF is more sensitive to 0.25% trypsin. Our research suggested that HEF can be used as feeder layer in culture of ES cells. HEF has longer service life than MEF and is worthy to be studied further.

Rabbit bone marrow-derived mesenchymal stem cells(MSCs) are multipotent. We studied the adipogenic and osteogenic differentiation potent using adipogenic supplement (AS) or osteogenic supplement (OS) in vitro. Specific markers of this induced adipogenic and osteogenic lineage were identified. The findings showed that the rabbit MSCs are capable of differentiating into adipogenic and osteogenic lineages spontaneously. On the 21st day, approximately 75% rabbit MSCs were induced to adipogenic or osteogenic cells in medium containing AS or OS, respectively. These results demonstrated that the differentiation of MSCs could be regulated in vitro. The underlying molecular mechanisms of adipogenic or osteogenic differentiation await elucidation.

The invasion and metastasis of malignant tumor cells are important factors causing the death of cancer patients. The proteolytic activity of proteinases to most of the extracellular matrix macromolecules is closely correlated with the invasion and metastasis of malignant tumor cells. Matrix metalloproteinases (MMP) are key proteinases involved in these processes. MMP is a type of Zn(2+)-depended proteinases. MMP2 and MMP9 are the unique types of proteinase that hydrolyze the bone structure of excellulary matrix (type IV collagen). So they are particularly correlated with leukemia cells infiltration and metastasis. This review aims to introduce the function of MMP and the regulation of matrix gene expression, as well as their roles in leukemia cell invasion and metastasis. A new strategy that MMP may be a therapeutic target in the treatment of leukemia is particularly introduced.

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. Peripheral blood (PB) and spleen were collected at 2,4 and 8 weeks after injection. Flow cytometry was performed to detect human cells in the rat PB, PCR was used to detect human cells in PB as well as spleen. The results showed that a definite proportion of human cells existed in peripheral blood of chimeric rat and the human specific beta2 microglobulin gene fragments were detected in spleen genomic DNA of chimeric rat. It is concluded that human/rat chimera model can be developed with neonatal rats. Human/rat xenograft model may provide a useful and convenient method for human hematopoietic stem cell assay in vivo.

To achieve efficient peripheral blood stem cell harvest (PBSCH), a simple method to monitor peripheral blood stem/progenitor cells was evaluated. The Sysmex XE-2100 hematology analyzer with an immature information (IMI) channel was used to identify and count the hematopoietic progenitor cell (HPC). Twenty-five donors mobilized with G-CSF in allogeneic and 11 patients in autologous peripheral blood stem cell transplantation (allo-PBSCT and auto-PBSCT) were involved. The HPC, CD34(+) cell and CFU-GM in the peripheral blood and leukapheresis samples were detected during mobilization and harvest. The results showed that HPC amount had a positive correlation with both the CD34(+) cell and CFU-GM in the peripheral blood. The peripheral blood hematopoietic stem/progenitor cells in allo-PBSCT donors remarkably increased on day 5 of the mobilization, followed the leukocytes increased. However, a fast increase of hematopoietic stem/progenitor cells was earlier than leukocytes in the peripheral blood. The HPC positively correlated with the CD34(+) cell or CFU-GM in the PBSCH. On the days of collection, the count of HPC and CD34(+) cell in peripheral blood was highly correlated with the CD34(+) cell yield. It is concluded that HPC as an estimate of progenitor cells in collected blood sample could be used to determine the optimal time of PBSCH and minimize the risk of missing an adequate harvest.

Angiotensin II (Ang II) is one active substance of renin-angiotensin system. In order to explore the effect of Ang II combined with various cytokines on proliferation and differentiation of cord blood CD34(+) cells, in vitro experiments of cell cultures of Ang II with or without cytokines were taken place. The results showed that Ang II stimulated both BFU-E and CFU-GM expansion. The numbers of BFU-E and CFU-GM raised with increase of Ang II concentrations ranged from 0.01 - 0.1 micro mol/L. In semi-solid culture assay, Ang II stimulated CFU-GM production but no effect on BFU-E occurred. The multiple number of CFU-GM increased from 2.3 +/- 0.8 to 7.8 +/- 1.9 times when Ang II was added into SCF + G-CSF + GM-CSF + IL-3 combination. Similarly, the multiple number of BFU-E increased from 3.1 +/- 1.8 to 9.2 +/- 2.3 times when Ang II was combined with SCF + EPO + TPO + IL-3. In conclusion, Ang II stimulated cord blood hematopoietic stem/progenitor cell expansion in vitro the in presence of various cytokines.

Notch signal path plays important roles in the regulation of proliferation and differentiation of hematopoietic stem cells. An extracellular domain of human Delta-like-1 (hDll-1(ext)), one of Notch ligands, was cloned and expressed in CHO cells, and the effect of hDll-1(ext) on expansion of hematopoietic stem/progenitor cells was investigated in this study. Total RNA was isolated from human marrow mononuclear cells. hDll-1(ext) was amplified by RT-PCR and cloned to T vector, then the gene was sequenced and subcloned to pcDNA3.1/Myc-His(+)A expression vector. The constructed plasmid was transfected into CHO cells with lipofectin and the expression of secreted hDll-1(ext) in G418-resistant clones was assayed by Western blot. hDll-1(ext) high-expressed clone was cultured to collect supernatant. Fusion protein hDll-1(ext) was purified from the supernatant by immobilized metal affinity chromatography (IMAC). The results showed that expression of Notch-1 receptor was detected in cord blood-derived CD34(+) cells by RT-PCR. Human umbilical blood CD34(+) cells were cultured in serum-free medium containing SCF, IL-3, VEGF, and with or without purified hDll-1(ext) for 4 or 8 days. Effect of hDll-1(ext) on the expansion of progenitor cells was analyzed then by clonogenic assays. The number of CFU-Mix and HPP-CFC generated from the culture system containing hDll-1(ext) was 1.5 times of that from the control. In conclusion, the recombinant hDll-1(ext) promotes the expansion of primitive hematopoietic progenitors.