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

Translation of stem cell research to industrial and clinical settings mostly requires large quantities of cells,especially those involving large organs such as the liver. A scalable reactor system is desirable to ensure a reliable supply of sufficient quantities of differentiated cells. To increase the culture efficiency in bioreactor system,high surface to volume ratio needs to be achieved. We employed a microcarrier culture system for the expansion of undifferentiated human embryonic stem cells (hESCs) as well as for directed differentiation of these cells to hepatocyte-like cells. Cells in single cell suspension were attached to the bead surface in even distribution and were expanded to 1??106cells/ml within 2 days of hESC culture with maintenance of the level of pluripotency markers. Directed differentiation into hepatocyte-like cells on microcarriers,both in static culture and stirred bioreactors,induced similar levels of hepatocyte-like cell differentiation as observed with cells cultured in conventional tissue culture plates. The cells expressed both immature and mature hepatocyte-lineage genes and proteins such as asialoglycoprotein receptor-1 (ASGPR-1) and albumin. Differentiated cells exhibited functional characteristics such as secretion of albumin and urea,and CYP3A4 activity could be detected. Microcarriers thus offer the potential for large-scale expansion and differentiation of hESCs induced hepatocyte-like cells in a more controllable bioreactor environment. ?? 2014. View Publication

The ability to manipulate transcription in human pluripotent stem cells (hPSCs) is fundamental for the discovery of key genes and mechanisms governing cellular state and differentiation. Recently developed CRISPR-effector systems provide a systematic approach to rapidly test gene function in mammalian cells,including hPSCs. In this review,we discuss recent advances in CRISPR-effector technologies that have been employed to control transcription through gene activation,gene repression,and epigenome engineering. We describe an application of CRISPR-effector mediated transcriptional regulation in hPSCs by targeting a synthetic promoter driving a GFP transgene,demonstrating the ease and effectiveness of CRISPR-effector mediated transcriptional regulation in hPSCs. View Publication

The successful use of specialized cells in regenerative medicine requires an optimization in the differentiation protocols that are currently used. Understanding the molecular events that take place during the differentiation of human pluripotent cells is essential for the improvement of these protocols and the generation of high quality differentiated cells. In an effort to understand the molecular mechanisms that govern differentiation we identify the methyltransferase SETD7 as highly induced during the differentiation of human embryonic stem cells and differentially expressed between induced pluripotent cells and somatic cells. Knock-down of SETD7 causes differentiation defects in human embryonic stem cell including delay in both the silencing of pluripotency-related genes and the induction of differentiation genes. We show that SETD7 methylates linker histone H1 in vitro causing conformational changes in H1. These effects correlate with a decrease in the recruitment of H1 to the pluripotency genes OCT4 and NANOG during differentiation in the SETD7 knock down that might affect the proper silencing of these genes during differentiation. View Publication

Progenitor cells have been extensively studied and therapeutically applied in tissue reconstructive therapy. Stromal vascular fraction (SVF) cells,which are derived from adipose tissue,may represent a potential source of the cells which undergo phenotypical differentiation into many lineages both in vitro as well as in vivo. The goal of this study was to check whether human SVF cells may differentiate into cardiomyocyte-like entities. Human SVF cells were induced to differentiate by their incubation in Methocult medium in the presence of SCF,IL-3 and IL-6. Morphological transformation of the cells was monitored using optical light microscope,whereas changes in expression of the genes typical for cardiac phenotype were measured by qRT-PCR. Incubation of the human SVF cells in the medium that promotes cardiomyocyte differentiation in vitro resulted in formation of myotubule-like structures accompanied by up-regulation of the myocardium-characteristic genes,such as GATA,MEF2C,MYOD1,but not ANP. Human SVF cells differentiate into cardiomyocyte-like cells in the presence of the certain set of myogenesis promoting cytokines. View Publication

Regulatory T cells (Treg) play an important role in regulating immune homeostasis in health and disease. Traditionally their suppressive function has been assayed by mixing purified cell populations,which does not provide an accurate picture of a physiologically relevant response. To overcome this limitation,we here develop ‘single cell suppression profiling of human Tregs’ (scSPOT). scSPOT uses a 52-marker CyTOF panel,a cell division detection algorithm,and a whole PBMC system to assess the effect of Tregs on all other cell types simultaneously. In this head-to-head comparison,we find Tregs having the clearest suppressive effects on effector memory CD8 T cells through partial division arrest,cell cycle inhibition,and effector molecule downregulation. Additionally,scSPOT identifies a Treg phenotypic split previously observed in viral infection and propose modes of action by the FDA-approved drugs Ipilimumab and Tazemetostat. scSPOT is thus scalable,robust,widely applicable,and may be used to better understand Treg immunobiology and screen for therapeutic compounds. Traditional regulatory T cell (Tregs) assays utilize mixture of purified cell population. Here the authors develop a ‘single cell suppression profiling of human Tregs’ (scSPOT) with 52-marker CyTOF panel,a cell division detection algorithm,and a whole PBMC system to assess Treg suppressive function on all cell types simultaneously. View Publication

Economic development has become a prominent issue for state governments. Nevertheless,states vary in the economic policies they choose. Two general approaches to the issue are discussed: the maintenance/attraction strategy and the creation strategy. Factor analysis allows us to gauge state effort on these two criteria. Regression analysis shows that political culture is an important factor in predicting which approach a state chooses,with traditionalistic states favoring the maintenance/attraction strategy,and moralistic states favoring the creation alternative. Other predictors of state policy choices include the condition of the economy and the diffusion of innovations. Also discussed is the interaction of political culture with other relevant variables in shaping state policies. View Publication

Robust in vitro lung models are required for risk assessment to measure key events leading to respiratory diseases. Primary normal human bronchial epithelial cells (NHBE) represent a good lung model but obtaining well-differentiated 3D cultures can be challenging. Here,we evaluated the ability to expand primary NHBE cells in different culture conditions while maintaining their 3D culture characteristics such as ciliated and goblet cells,and ion channel function. Differentiated cultures were optimally obtained with PneumaCult-Ex Plus (expansion medium)/PneumaCult-ALI (differentiation medium). Primary cells passaged up to four times maintained airway epithelial characteristics as evidenced by ciliated pseudostratified columnar epithelium with goblet cells,trans-epithelial electrical resistance (TEER) ({\textgreater}400 Ohms.cm2),and cystic fibrosis transmembrane conductance regulator-mediated short-circuit currents ({\textgreater}3 µA/cm2). No change in ciliary beat frequency (CBF) or airway surface liquid (ASL) meniscus length was observed up to passage six. For the first time,this study demonstrates that CFTR ion channel function and normal epithelial phenotypic characteristics are maintained in passaged primary NHBE cells. Furthermore,this study highlights the criticality of evaluating expansion and differentiation conditions for achieving optimal phenotypic and functional endpoints (CBF,ASL,ion channel function,presence of differentiated cells,TEER) when developing in vitro lung models. View Publication

Hematologic malignancies such as acute and chronic myeloid leukemia are characterized by the malignant transformation of immature CD34(+) progenitor cells. Transformation is associated with elevated expression of the Wilm's tumor gene encoded transcription factor (WT1). Here we demonstrate that WT1 can serve as a target for cytotoxic T lymphocytes (CTL) with exquisite specificity for leukemic progenitor cells. HLA-A0201- restricted CTL specific for WT1 kill leukemia cell lines and inhibit colony formation by transformed CD34(+) progenitor cells isolated from patients with chronic myeloid leukemia (CML),whereas colony formation by normal CD34(+) progenitor cells is unaffected. Thus,the tissue-specific transcription factor WT1 is an ideal target for CTL-mediated purging of leukemic progenitor cells in vitro and for antigen-specific therapy of leukemia and other WT1-expressing malignancies in vivo. View Publication

Mesenchymal stem cells (MSCs) may be used as powerful tools for the repair and regeneration of damaged tissues. However,isolating tissue specific-derived MSCs may cause pain and increased infection rates in patients,and repetitive isolations may be required. To overcome these difficulties,we have examined alternative methods for MSC production. Here,we show that induced pluripotent stem cells (iPSCs) may be differentiated into mesenchymal stem cells (iMSCs) following exposure to SB431542. Purified iMSCs were administered to mdx mice to study skeletal muscle regeneration in a murine model of muscular dystrophy. Purified iMSCs displayed fibroblast-like morphology,formed three-dimensional spheroid structures,and expressed characteristic mesenchymal stem cell surface markers such as CD29,CD33,CD73,CD90,and CD105. Moreover,iMSCs were capable of differentiating into adipogenic,osteogenic,and chondrogenic lineages. Transplanting iMSC cells to tibialis anterior skeletal muscle tissue in mdx mice lowered oxidative damage as evidenced by a reduction in nitrotyrosine levels,and normal dystrophin expression levels were restored. This study demonstrates the therapeutic potential of purified iMSCs in skeletal muscle regeneration in mdx mice,and suggests that iPSCs are a viable alternate source for deriving MSCs as needed. textcopyright 2014 Elsevier Inc. View Publication

Allogeneic cell therapies,such as those involving macrophages or Natural Killer (NK) cells,are of increasing interest for cancer immunotherapy. However,the current techniques for genetically modifying these cell types using lenti- or gamma-retroviral vectors present challenges,such as required cell pre-activation and inefficiency in transduction,which hinder the assessment of preclinical efficacy and clinical translation. In our study,we describe a novel lentiviral pseudotype based on the Koala Retrovirus (KoRV) envelope protein,which we identified based on homology to existing pseudotypes used in cell therapy. Unlike other pseudotyped viral vectors,this KoRV-based envelope demonstrates remarkable efficiency in transducing freshly isolated primary human NK cells directly from blood,as well as freshly obtained monocytes,which were differentiated to M1 macrophages as well as B cells from multiple donors,achieving up to 80% reporter gene expression within three days post-transduction. Importantly,KoRV-based transduction does not compromise the expression of crucial immune cell receptors,nor does it impair immune cell functionality,including NK cell viability,proliferation,cytotoxicity as well as phagocytosis of differentiated macrophages. Preserving immune cell functionality is pivotal for the success of cell-based therapeutics in treating various malignancies. By achieving high transduction rates of freshly isolated immune cells before expansion,our approach enables a streamlined and cost-effective automated production of off-the-shelf cell therapeutics,requiring fewer viral particles and less manufacturing steps. This breakthrough holds the potential to significantly reduce the time and resources required for producing e.g. NK cell therapeutics,expediting their availability to patients in need. Subject terms: Genetic transduction,Tumour immunology,Immunotherapy,Genetic vectors,Innate immune cells View Publication

Developing novel therapies that suppress self-renewal of leukemia stem cells may reduce the likelihood of relapses and extend long-term survival of patients with acute myelogenous leukemia (AML). AML1-ETO (AE) is an oncogene that plays an important role in inducing self-renewal of hematopoietic stem/progenitor cells (HSPCs),leading to the development of leukemia stem cells. Previously,using a zebrafish model of AE and a whole-organism chemical suppressor screen,we have discovered that AE induces specific hematopoietic phenotypes in embryonic zebrafish through a cyclooxygenase (COX)-2 and β-catenin-dependent pathway. Here,we show that AE also induces expression of the Cox-2 gene and activates β-catenin in mouse bone marrow cells. Inhibition of COX suppresses β-catenin activation and serial replating of AE(+) mouse HSPCs. Genetic knockdown of β-catenin also abrogates the clonogenic growth of AE(+) mouse HSPCs and human leukemia cells. In addition,treatment with nimesulide,a COX-2 selective inhibitor,dramatically suppresses xenograft tumor formation and inhibits in vivo progression of human leukemia cells. In summary,our data indicate an important role of a COX/β-catenin-dependent signaling pathway in tumor initiation,growth,and self-renewal,and in providing the rationale for testing potential benefits from common COX inhibitors as a part of AML treatments. View Publication