搜索结果: 'methocult media formulations for mouse hematopoietic cells serum containing'

Multiple myeloma is characterized by the clonal expansion of neoplastic plasma cells within the bone marrow,elevated serum immunoglobulin,and osteolytic bone disease. The disease is highly responsive to a wide variety of anticancer treatments including conventional cytotoxic chemotherapy,corticosteroids,radiation therapy,and a growing number of agents with novel mechanisms of action. However,few if any patients are cured with these modalities and relapse remains a critical issue. A better understanding of clonogenic multiple myeloma cells is essential to ultimately improving long-term outcomes,but the nature of the cells responsible for myeloma regrowth and disease relapse is unclear. We review evidence that functional heterogeneity exists in multiple myeloma and discuss potential strategies and clinical implications of the stem-cell model of cancer in this disease. View Publication

Ectopic expression of transcription factors can reprogram somatic cells to a pluripotent state. However,most of the studies used skin fibroblasts as the starting population for reprogramming,which usually take weeks for expansion from a single biopsy. We show here that induced pluripotent stem (iPS) cells can be generated from adult human adipose stem cells (hASCs) freshly isolated from patients. Furthermore,iPS cells can be readily derived from adult hASCs in a feeder-free condition,thereby eliminating potential variability caused by using feeder cells. hASCs can be safely and readily isolated from adult humans in large quantities without extended time for expansion,are easy to maintain in culture,and therefore represent an ideal autologous source of cells for generating individual-specific iPS cells. View Publication

Motor neuron diseases (MNDs) are a group of neurological disorders that selectively affect motor neurons. There are currently no cures or efficacious treatments for these diseases. In recent years,significant developments in stem cell research have been applied to MNDs,particularly regarding neuroprotection and cell replacement. However,a consistent source of motor neurons for cell replacement is required. Human embryonic stem cells (hESCs) could provide an inexhaustible supply of differentiated cell types,including motor neurons that could be used for MND therapies. Recently,it has been demonstrated that induced pluripotent stem (iPS) cells may serve as an alternative source of motor neurons,since they share ES characteristics,self-renewal,and the potential to differentiate into any somatic cell type. In this review,we discuss several reproducible methods by which hESCs or iPS cells are efficiently isolated and differentiated into functional motor neurons,and possible clinical applications. View Publication

Cardiovascular progenitor cells (CVPCs) derived from human embryonic stem cells and human induced pluripotent stem cells represent an invaluable potential source for the study of early embryonic cardiovascular development and stem cell-based therapies for congenital and acquired heart diseases. To fully realize their values,it is essential to establish an efficient and stable differentiation system for the induction of these pluripotent stem cells (PSCs) into the CVPCs and robustly expand them in culture,and then further differentiate these CVPCs into multiple cardiovascular cell types. Here we describe the protocols for efficient derivation,expansion,and differentiation of CVPCs from hPSCs in a chemically defined medium under feeder- and serum-free culture conditions. View Publication

Peripheral blood is the easy-to-access,minimally invasive,and the most abundant cell source to use for cell reprogramming. The episomal vector is among the best approaches for generating integration-free induced pluripotent stem (iPS) cells due to its simplicity and affordability. Here we describe the detailed protocol for the efficient generation of integration-free iPS cells from peripheral blood mononuclear cells. With this optimized protocol,one can readily generate hundreds of iPS cell colonies from 1 ml of peripheral blood. View Publication

BACKGROUND Neuronal stem cells (NSCs) are promising for neurointestinal disease therapy. Although NSCs have been isolated from intestinal musclularis,their presence in mucosa has not been well described. Mucosa-derived NSCs are accessible endoscopically and could be used autologously. Brain-derived Nestin-positive NSCs are important in endogenous repair and plasticity. The aim was to isolate and characterize mucosa-derived NSCs,determine their relationship to Nestin-expressing cells and to demonstrate their capacity to produce neuroglial networks in vitro and in vivo. METHODS Neurospheres were generated from periventricular brain,colonic muscularis (Musc),and mucosa-submucosa (MSM) of mice expressing green fluorescent protein (GFP) controlled by the Nestin promoter (Nestin-GFP). Neuronal stem cells were also grown as adherent colonies from intestinal mucosal organoids. Their differentiation potential was assessed using immunohistochemistry using glial and neuronal markers. Brain and gut-derived neurospheres were transplanted into explants of chick embryonic aneural hindgut to determine their fate. KEY RESULTS Musc- and MSM-derived neurospheres expressed Nestin and gave rise to cells of neuronal,glial,and mesenchymal lineage. Although Nestin expression in tissue was mostly limited to glia co-labelled with glial fibrillary acid protein (GFAP),neurosphere-derived neurons and glia both expressed Nestin in vitro,suggesting that Nestin+/GFAP+ glial cells may give rise to new neurons. Moreover,following transplantation into aneural colon,brain- and gut-derived NSCs were able to differentiate into neurons. CONCLUSIONS & INFERENCES Nestin-expressing intestinal NSCs cells give rise to neurospheres,differentiate into neuronal,glial,and mesenchymal lineages in vitro,generate neurons in vivo and can be isolated from mucosa. Further studies are needed for exploring their potential for treating neuropathies. View Publication

OBJECTIVE The differentiation program for human thyroid follicular cells (TFCs) relies on the interplay between sequence-specific transcription factors and transcriptional co-regulators. Transcriptional co-activator with PDZ-binding motif (TAZ) is a co-activator that regulates several transcription factors,including PAX8 and NKX2-1,which play a central role in thyroid-specific gene transcription. TAZ and PAX8/NKX2-1 are co-expressed in the nuclei of thyroid cells,and TAZ interacts directly with both PAX8 and NKX2-1,leading to their enhanced transcriptional activity on the thyroglobulin (TG) promoter and additional genes. METHODS The use of a small molecule,ethacridine,recently identified as a TAZ activator,in the differentiation of thyroid cells from human embryonic stem (hES) cells was studied. First,endodermal cells were derived from hES cells using Activin A,followed by induction of differentiation into thyroid cells directed by ethacridine and thyrotropin (TSH). RESULTS The expression of TAZ was increased in the Activin A-derived endodermal cells by ethacridine in a dose-dependent manner and followed by increases in PAX8 and NKX2-1 when assessed by both quantitative polymerase chain reaction and immunostaining. Following further differentiation with the combination of ethacridine and TSH,the thyroid-specific genes TG,TPO,TSHR,and NIS were all induced in the differentiated hES cells. When these cells were cultured with extracellular matrix-coated dishes,thyroid follicle formation and abundant TG protein expression were observed. Furthermore,such hES cell-derived thyroid follicles showed a marked TSH-induced and dose-dependent increase in radioiodine uptake and protein-bound iodine accumulation. CONCLUSION These data show that fully functional human thyroid cells can be derived from hES cells using ethacridine,a TAZ activator,which induces thyroid-specific gene expression and promotes thyroid cell differentiation from the hES cells. These studies again demonstrate the importance of transcriptional regulation in thyroid cell development. This approach also yields functional human thyrocytes,without any gene transfection or complex culture conditions,by directly manipulating the transcriptional machinery without interfering with intermediate signaling events. View Publication

The mechanisms involved in the regulation of vasculogenesis still remain unclear in mammals. Totipotent embryonic stem (ES) cells may represent a suitable in vitro model to study molecular events involved in vascular development. In this study,we followed the expression kinetics of a relatively large set of endothelial-specific markers in ES-derived embryoid bodies (EBs). Results of both reverse transcription-polymerase chain reaction and/or immunofluorescence analysis show that a spontaneous endothelial differentiation occurs during EBs development. ES-derived endothelial cells express a full range of cell lineage-specific markers: platelet endothelial cell adhesion molecule (PECAM),Flk-1,tie-1,tie-2,vascular endothelial (VE) cadherin,MECA-32,and MEC-14.7. Analysis of the kinetics of endothelial marker expression allows the distinction of successive maturation steps. Flk-1 was the first to be detected; its mRNA is apparent from day 3 of differentiation. PECAM and tie-2 mRNAs were found to be expressed only from day 4,whereas VE-cadherin and tie-1 mRNAs cannot be detected before day 5. Immunofluorescence stainings of EBs with antibodies directed against Flk-1,PECAM,VE-cadherin,MECA-32,and MEC-14.7 confirmed that the expression of these antigens occurs at different steps of endothelial cell differentiation. The addition of an angiogenic growth factor mixture including erythropoietin,interleukin-6,fibroblast growth factor 2,and vascular endothelial growth factor in the EB culture medium significantly increased the development of primitive vascular-like structures within EBs. These results indicate that this in vitro system contains a large part of the endothelial cell differentiation program and constitutes a suitable model to study the molecular mechanisms involved in vasculogenesis. View Publication

Human embryonic stem cells (hESCs) have the potential to generate multiple cell types and hold promise for future therapeutic applications. Although undifferentiated hESCs can proliferate indefinitely,hESC derivatives significantly downregulate telomerase and have limited replication potential. In this study we examine whether the replicative lifespan of hESC derivatives can be extended by ectopic expression of human telomerase reverse transcriptase (hTERT),the catalytic component of the telomerase complex. To this end,we have derived HEF1 cells,a fibroblast-like cell type,differentiated from hESCs. Infection of HEF1 cells with a retrovirus expressing hTERT extends their replicative capacity,resulting in immortal human HEF1-hTERT cells. HEF1-hTERT cells can be used to produce conditioned medium (CM) capable of supporting hESC growth under feeder-free conditions. Cultures maintained in HEF1-CM show characteristics similar to mouse embryonic fibroblast CM control cultures,including morphology,surface marker and transcription factor expression,telomerase activity,differentiation,and karyotypic stability. In addition,HEF1-hTERT cells have the capacity to differentiate into cells of the osteogenic lineage. These results suggest that immortalized cell lines can be generated from hESCs and that cells derived from hESCs can be used to support their own growth,creating a genotypically homogeneous system for the culture of hESCs. View Publication