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

Recent clinical studies suggest that adoptive transfer of donor-derived natural killer (NK) cells may improve clinical outcome in hematological malignancies and some solid tumors by direct anti-tumor effects as well as by reduction of graft versus host disease (GVHD). NK cells have also been shown to enhance transplant engraftment during allogeneic hematopoietic stem cell transplantation (HSCT) for hematological malignancies. The limited ex vivo expansion potential of NK cells from peripheral blood (PB) or umbilical cord blood (UCB) has however restricted their therapeutic potential. Here we define methods to efficiently generate NK cells from donor-matched,full-term human placenta perfusate (termed Human Placenta-Derived Stem Cell,HPDSC) and UCB. Following isolation from cryopreserved donor-matched HPDSC and UCB units,CD56+CD3- placenta-derived NK cells,termed pNK cells,were expanded in culture for up to 3 weeks to yield an average of 1.2 billion cells per donor that were textgreater80% CD56+CD3-,comparable to doses previously utilized in clinical applications. Ex vivo-expanded pNK cells exhibited a marked increase in anti-tumor cytolytic activity coinciding with the significantly increased expression of NKG2D,NKp46,and NKp44 (p textless 0.001,p textless 0.001,and p textless 0.05,respectively). Strong cytolytic activity was observed against a wide range of tumor cell lines in vitro. pNK cells display a distinct microRNA (miRNA) expression profile,immunophenotype,and greater anti-tumor capacity in vitro compared to PB NK cells used in recent clinical trials. With further development,pNK may represent a novel and effective cellular immunotherapy for patients with high clinical needs and few other therapeutic options. View Publication

Conventional human embryonic stem cells (hESCs) are capable of self-renewal and simultaneously poised for differentiation. But the mechanisms underlying this primed pluripotent state,which endows them with elevated responsiveness to differentiation cues,remain largely underexplored. Especially,little is known about the pivotal transcription factors (TFs) that orchestrate hESCs towards primed pluripotency. Here,we report a function of TF ZNF263 in pluripotency priming. Genetic and functional assays reveal that ZNF263 directly initiates the incipient expression of early differentiation genes and concurrently dampens the core pluripotency circuitry in hESCs,greatly tilting the balance from pluripotency maintenance to lineage priming. Importantly,ZNF263 deficiency markedly impairs pluripotency dissolution and multi-lineage differentiation in hESCs,particularly toward ectoderm. Moreover,single-cell transcriptomic profiling reveals that ZNF263 promotes the priming of cell fate commitment in hESCs,suggesting its indispensable requirement for pluripotency priming and lineage commitment continuum. Together,we demonstrate the role of ZNF263 in establishing the primed pluripotent state in hESCs and facilitating their differentiation into primary germ layer lineages. Human embryonic stem cells are simultaneously capable of self-renewal and poised for differentiation. Here,the authors show a role for the ZNF263 transcription factor promotes primed pluripotency and facilitates differentiation into primary germ layer lineages. View Publication

Introduction: Human embryonic stem cells (hESC) provide an invaluable model for assessing the effects of environmental chemicals and drugs on human prenatal development. However,hESC are difficult to adapt to 96-well plate screening assays,because they survive best when plated as colonies,which are difficult to count and plate accurately. The purpose of this study is to present an experimental method and analysis procedure to accomplish reliable screening of toxicants using hESC. Methods: We present a method developed to rapidly and easily determine the number of cells in small colonies of hESC spectrophotometerically and then accurately dispense equivalent numbers of cells in 96-well plates. The MTT assay was used to evaluate plating accuracy,and the method was tested using known toxicants. Results: The quality of the plate set-up and analysis procedure was evaluated with NIH plate validation and assessment software. All statistical parameters measured by the software were acceptable,and no drift or edge effects were observed. The 96-well plate MTT assay with hESC was tested by performing a dose-response screen of commercial products,which contain a variety of chemicals. The screen was done using single wells/dose,and the reliability of this method was demonstrated in a subsequent screen of the same products repeated three times. The single and triple screens were in good agreement,and NOAELs and IC50s could be determined from the single screen. The effects of vapor from volatile chemicals were studied,and methods to monitor and avoid vapor effects were incorporated into the assay. Discussion: Our method overcomes the difficulty of using hESC for reliable quantitative 96-well plate assays. It enables rapid dose-response screening using equipment that is commonly available in laboratories that culture hESC. This method could have a broad application in studies of environmental chemicals and drugs using hESC as models of prenatal development. ?? 2012 Elsevier Inc. View Publication

Myocardial infarction is a leading cause of mortality and morbidity worldwide,and current treatments fail to address the underlying scarring and cell loss,which is a major cause of heart failure after infarction. The novel strategy,therapeutic angiogenesis and/or vasculogenesis with endothelial progenitor cells transplantation holds great promise to increase blood flow in ischemic areas,thus rebuild the injured heart and reverse the heart failure. Given the potential of self-renewal and differentiation into virtually all cell types,human embryonic stem cells (hESCs) may provide an alternate source of therapeutic cells by allowing the derivation of large numbers of endothelial cells for therapeutic angiogenesis and/or vasculogenesis of ischemic heart diseases. Moreover,to fully understand the fate of implanted hESCs or hESC derivatives,investigators need to monitor the motility of cells in living animals over time. In this chapter,we describe the application of bioluminescence reporter gene imaging to track the transplanted hESC-derived endothelial cells for treatment of myocardial infarction. The technology of inducing endothelial cells from hESCs will also be discussed. View Publication

Williams syndrome is a genetic neurodevelopmental disorder characterized by an uncommon hypersociability and a mosaic of retained and compromised linguistic and cognitive abilities. Nearly all clinically diagnosed individuals with Williams syndrome lack precisely the same set of genes,with breakpoints in chromosome band 7q11.23 (refs 1-5). The contribution of specific genes to the neuroanatomical and functional alterations,leading to behavioural pathologies in humans,remains largely unexplored. Here we investigate neural progenitor cells and cortical neurons derived from Williams syndrome and typically developing induced pluripotent stem cells. Neural progenitor cells in Williams syndrome have an increased doubling time and apoptosis compared with typically developing neural progenitor cells. Using an individual with atypical Williams syndrome,we narrowed this cellular phenotype to a single gene candidate,frizzled 9 (FZD9). At the neuronal stage,layer V/VI cortical neurons derived from Williams syndrome were characterized by longer total dendrites,increased numbers of spines and synapses,aberrant calcium oscillation and altered network connectivity. Morphometric alterations observed in neurons from Williams syndrome were validated after Golgi staining of post-mortem layer V/VI cortical neurons. This model of human induced pluripotent stem cells fills the current knowledge gap in the cellular biology of Williams syndrome and could lead to further insights into the molecular mechanism underlying the disorder and the human social brain. View Publication

Mitochondrial membrane potential (MMP) segregates functionally distinct subsets within highly purified hematopoietic stem cells (HSCs). Here,we detail a protocol for FACS isolation of MMP sub-fractions of phenotypically defined mouse and human HSCs. These steps are followed by high-/super-resolution immunofluorescence microscopy of HSCs' lysosomes. While the protocol describes the isolation of quiescent HSCs,which are the most potent subsets,it could also be applied to other HSC subsets. This protocol overcomes some experimental challenges associated with low HSC numbers. For complete details on the use and execution of this protocol,please refer to Liang et al. (2020) and Qiu et al. (2021). View Publication

Human embryonic stem (hES) cell production of heparan sulfate influences cell fate and pluripotency. Human ES cells remain pluripotent in vitro through the action of growth factors signaling,and the activity of these factors depends on interaction with specific receptors and also with heparan sulfate. Here,we tested the hypothesis that matrix-associated heparan sulfate is enough to maintain hES cells under low fibroblast growth factor-2 concentration in the absence of live feeder cells. To pursue this goal,we compared hES cells cultured either on coated plates containing live murine embryonic fibroblasts (MEFs) or on a matrix derived from ethanol-fixed MEFs. hES cells were analyzed for the expression of pluripotency markers and the ability to form embryoid bodies. hES cells cultured either on live mouse fibroblasts or onto a matrix derived from fixed fibroblasts expressed similar levels of Oct-4,SOX-2,Nanog,TRA-1-60 and SSEA-4,and they were also able to form cavitated embryoid bodies. Heparan sulfate-depleted matrix lost the ability to support the adherence and growth of hES cells,confirming that this glycosaminoglycan,bound to the extracellular matrix,is enough for the growth and attachment of hES cells. Finally,we observed that the ethanol-fixed matrix decreases by 30% the levels of Neu5Gc in hES cells,indicating that this procedure reduces xeno-contamination. Our data suggest that matrix-bound heparan sulfate is required for the growth and pluripotency of hES cells and that ethanol-fixed MEFs may be used as a live cell"-free substrate for stem cells." View Publication

View Publication

Zeb2 (Sip1/Zfhx1b) is a member of the zinc-finger E-box-binding (ZEB) family of transcriptional repressors previously demonstrated to regulate epithelial-to-mesenchymal transition (EMT) processes during embryogenesis and tumor progression. We found high Zeb2 mRNA expression levels in HSCs and hematopoietic progenitor cells (HPCs),and examined Zeb2 function in hematopoiesis through a conditional deletion approach using the Tie2-Cre and Vav-iCre recombination mouse lines. Detailed cellular analysis demonstrated that Zeb2 is dispensable for hematopoietic cluster and HSC formation in the aorta-gonadomesonephros region of the embryo,but is essential for normal HSC/HPC differentiation. In addition,Zeb2-deficient HSCs/HPCs fail to properly colonize the fetal liver and/or bone marrow and show enhanced adhesive properties associated with increased β1 integrin and Cxcr4 expression. Moreover,deletion of Zeb2 resulted in embryonic (Tie2-Cre) and perinatal (Vav-icre) lethality due to severe cephalic hemorrhaging and decreased levels of angiopoietin-1 and,subsequently,improper pericyte coverage of the cephalic vasculature. These results reveal essential roles for Zeb2 in embryonic hematopoiesis and are suggestive of a role for Zeb2 in hematopoietic-related pathologies in the adult. View Publication