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BACKGROUND:Endothelial progenitor cells have good prospects for clinical application;especial y as seed cells, they are involved in construction of tissue engineered blood vessels and disease treatment. OBJECTIVE:To investigate the biological characteristics of endothelial progenitor cells derived from granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood. METHODS:Mononuclear cells from G-CSF mobilized peripheral blood (n=9) and normal adult peripheral blood (n=8) were obtained and cultured in expanded medium. The immunophenotype of endothelial progenitor cells was investigated by FACS and immunohistochemistry. Real-time PCR was used to detect the expression of different cytokines. Proliferation and adhesion ability of endothelial progenitor cells were detected by MTT assay and adhesion assay. Moreover, the abilities of vasculogenesis in vitro and Dil-labeled acetylated low density lipoprotein uptake were detected. The acquired cells were seeded onto the basilar membrane gel containing vascular endothelial growth factor and basic fibroblast growth factor to induce angiogenesis. RESULTS AND CONCLUSION:Endothelial progenitor cells derived from G-CSF mobilized peripheral blood were similar to those from normal adult peripheral blood in phenotype and morphology. FACSs and immunohistochemistry showed that endothelial progenitor cells were positive for endothelial cellmarkers, such as CD31, vWF, CD34, FLK-1, VE-Cadherin and CD133. In addition, the expression of vascular endothelial growth factor and stromal cel-derived factor 1 were significantly increased in G-CSF mobilized endothelial progenitor cells. Moreover, endothelial progenitor cells derived from two sources possessed the abilities of angiogenesis in vitro and Dil-labeled acetylated low density lipoprotein uptake. But, the number and the proliferation ability of endothelial progenitor cells derived from G-CSF mobilized peripheral blood were better than that of endothelial progenitor cells derived from normal adult peripheral blood. These findings indicate that there is a population of cells with characteristics of endothelial progenitor cells in G-CSF mobilized peripheral blood. They possess the abilities of vasculogenesis in vitro. Moreover, compared to endothelial progenitor cells derived from normal adult peripheral blood, we could obtain more endothelial progenitor cells in G-CSF mobilized peripheral blood and those cells show better proliferation ability.
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Objective To study the immunogenicity,immune modulatory effects and mechanisms of mesenthymal stem ceils (MSCs) derived from the bone marrow of patients with multiple myeloma (MM).Methods The mononuclear cells from the bone marrow of MM patients were obtained and cultured.Immunophenotypes were investigated by using FACS.The levels of cytokines were determined by using enzyme linked immunosorbant assay (ELISA).The endocytosis of monocyte-derived dendritic cells (DCs) was investigated by using FACS.Moreover,the immunoregulatory ability of DCs on proliferation of T lymphocytes was detected by using mixed lymphocyte culture assay.Results MM-derived MSCs had no expression of HLA-DR and costirnulatory molecules (CD40,CD80,CD83 and CD86).MM-derived MSCs could significantly suppress proliferation of T lymphocytes in a dose-dependent manner,which could be reversed by antiTGF-β1 and anti-HGF antibodies.MM-derived MSCs inhibit the endocytosis of DCs.MM-derived MSCs could inhibit the secretion of IL-12 and significantly inhibit the function of DCs on proliferation of T lymphocytes.Conclusion MM-derived MSCs harbored low immunogenicity and immunoregulatory effect in vitro,and this effect was achieved through cytokines.
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BACKGROUND:Bone marrow mesenchymal stem cells derived from multiple myeloma patients are characterized by pluripotential differentiation, immunoregulation and supporting hematopoiesis, but whether these features are affected after cryopreservation is unclear. OBJECTIVE:To study the biological characteristics of cryopreserved bone marrow mesenthymal stem cellderived from multiple myeloma patients. METHODS:Bone marrow mesenchymal stem cells derived from multiple myeloma patients were cryopreserved in-196 ℃ liquid nitrogen for 1 month (short term) and 12 months (long term) with Iscove’s modified Dulbecco’s medium containing 10%dimethyl sulfoxide and 40%fetal bovine serum as cryoprotectant. The viability and proliferation ability of thawed bone marrow mesenchymal stem cells were investigated. Hematopoiesis support of thawed bone marrow mesenchymal stem cells in vitro was detected by long-term bone marrow culture and the methylcellulose progenitor assay. The immunoregulatory ability of thawed mesenchymal stem cells was detected by mixed lymphocyte culture assay. RESULTS AND CONCLUSION:The cellviability was (92.9±7.5)%and (86.7±9.2)%for mesenchymal stem cells cryopreserved as long as 1 month or 12 months, respectively. Furthermore, thawed bone marrow mesenchymal stem cells possessed the ability of supporting colony forming and could significantly suppress proliferation of T lymphocytes. At last, there were no changes detected as compared with pre-cryopreserved mesenchymal stem cells in the abilities of proliferation, hematopoiesis support and immunoregulation. Cryopreservation can decrease the cellviability of bone marrow mesenchymal stem cells derived from the patients with multiple myeloma, but cannot affect the abilities of proliferation, hematopoiesis support and immunoregulation.
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In order to amplify the complete genome of enJSRV from the strain of Inner Mongolia (enJSRV-NM), we used enJSRV-specific and JSRV-specific DNA probes in dot blot hybridization. Seven pairs of primers were designed based on Genbank sequences. Seven fragments were obtained by PCR and were cloned into the PMD19- T vectors. The recombinant plasmids were sequenced and analyzed. The results showed that the genome was 7 942 bp in length and contained four overlapping open reading frames corresponding to the gag, pro, pol and env genes as well as an additional open reading frame (orf-x) that overlaps the 3' end of the pol gene. The nucleotide acid sequences of the enJSRV-NM loci were compared with the sequences of South Africa enJS56A1 strain (Accession No. AF153615) and USA JSRV21 strain (Accession No. AF105220). The nucleotide acid identities were 99.2% and 92.3% respectively. Two zinc fingers were found in the NC region in the predicted amino acid sequence. However, the YXXM motif, which is a reliable molecular marker for the infectious exogenous virus, was not found in the TM region. It was found that the enJSRV-NM region was 90%-98% identical at the amino acid level to its exogenous infectious counterparts in most of the retroviral genome. This is the first nucleotide sequence of enJSRV reported in P.R China. The resource work has provided a wide range of information useful not only for expression genomics and annotation of genomic DNA sequence, but also for further research on the clinical diagnosis of OPA.