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

Melanoma,a potentially lethal skin cancer,is widely thought to be immunogenic in nature. While there has been much focus on T cell-mediated immune responses,limited knowledge exists on the role of mature B cells. We describe an approach,including a cell-based ELISA,to evaluate mature IgG antibody responses to melanoma from human peripheral blood B cells. We observed a significant increase in antibody responses from melanoma patients (n = 10) to primary and metastatic melanoma cells compared to healthy volunteers (n = 10) (Ptextless0.0001). Interestingly,we detected a significant reduction in antibody responses to melanoma with advancing disease stage in our patient cohort (n = 21) (Ptextless0.0001). Overall,28% of melanoma patient-derived B cell cultures (n = 1,800) compared to 2% of cultures from healthy controls (n = 600) produced antibodies that recognized melanoma cells. Lastly,a patient-derived melanoma-specific monoclonal antibody was selected for further study. This antibody effectively killed melanoma cells in vitro via antibody-mediated cellular cytotoxicity. These data demonstrate the presence of a mature systemic B cell response in melanoma patients,which is reduced with disease progression,adding to previous reports of tumor-reactive antibodies in patient sera,and suggesting the merit of future work to elucidate the clinical relevance of activating humoral immune responses to cancer. View Publication

Realizing the potential of human pluripotent stem cell (hPSC)-based therapy requires the development of defined scalable culture systems with efficient expansion,differentiation and isolation protocols. We report an engineered 3D microfiber system that efficiently supports long-term hPSCs self-renewal under chemically defined conditions. The unique feature of this system lies in the application of a 3D ECM-like environment in which cells are embedded,that affords: (i) uniform high cell loading density in individual cell-laden constructs (∼10 7 cells/ml); (ii) quick recovery of encapsulated cells (textless10min at 37°C) with excellent preservation of cell viability and 3D multicellular structure; (iii) direct cryopreservation of the encapsulated cells in situ in the microfibers with textgreater17-fold higher cell viability compared to those cultured on Matrigel surface; (iv) long-term hPSC propagation under chemically defined conditions. Four hPSC lines propagated in the microfibrous scaffold for 10 consecutive passages were capable of maintaining an undifferentiated phenotype as demonstrated by the expression of stem cell markers and stable karyotype invitro and the ability to form derivatives of the three germ layers both invitro and invivo. Our 3D microfibrous system has the potential for large-scale cultivation of transplantable hESCs and derivatives for clinical applications. textcopyright 2011 Elsevier Ltd. View Publication

Molecular- and cellular-based therapies have the potential to reduce obesity-associated disease. In response to cold,beige adipocytes form in subcutaneous white adipose tissue and convert energy stored in metabolic substrates to heat,making them an attractive therapeutic target. We developed a robust method to generate a renewable source of human beige adipocytes from induced pluripotent stem cells (iPSCs). Developmentally,these cells are derived from FOXF1+ mesoderm and progress through an expandable mural-like mesenchymal stem cell (MSC) to form mature beige adipocytes that display a thermogenically active profile. This includes expression of uncoupling protein 1 (UCP1) concomitant with increased uncoupled respiration. With this method,dysfunctional adipogenic precursors can be reprogrammed and differentiated into beige adipocytes with increased thermogenic function and anti-diabetic secretion potential. This resource can be used to (1) elucidate mechanisms that underlie the control of beige adipogenesis and (2) generate material for cellular-based therapies that target metabolic syndrome in humans. View Publication

Brain Microphysiological Systems,including neural organoids derived from human induced pluripotent stem cells,offer a unique lens to study the intricate workings of the human brain. This paper investigates the foundational elements of learning and memory in neural organoids by quantifying immediate early gene expression in response to chemical modulation,input-specific short- and long-term synaptic plasticity,neuronal network dynamics,connectivity,and criticality to demonstrate the utility of these organoids in basic science research. Neural organoids showed synapse formation,glutamatergic and GABAergic receptor expression,immediate early gene expression basally and evoked,functional connectivity,criticality,and synaptic plasticity in response to theta-burst stimulation. In addition,pharmacological interventions on GABAergic and glutamatergic receptors and input-specific theta-burst stimulation further shed light on the capacity of neural organoids to mirror synaptic modulation,specifically short- and long-term potentiation and depression,demonstrating their potential as tools for studying neurophysiological and neurological processes and informing therapeutic strategies for diseases. Neural organoids exhibit key aspects of learning and memory,including input-specific synaptic plasticity,basal and evoked immediate early gene expression,and critical network dynamics,highlighting their value in modeling human neurophysiology. View Publication

Plasmacytoid dendritic cells (pDCs) are multifunctional immune cells with roles in both the innate and adaptive immune system. Their hallmark function is production of large amounts of type I interferons in response to viral infections,but they are also capable of producing a range of other cytokines,antigen presentation,and cytotoxicity. Their potential as an immunotherapy for cancer and infectious disease is being explored,but broad application of these cells is challenged by low frequency in the blood and low viability during ex vivo culturing. We have previously developed an effective in vitro differentiation protocol for producing pDCs from CD34+ hematopoietic stem and progenitor cells (HSPC-pDCs),which provides an attainable and large source of pDCs. HSPC-pDCs present pDC characteristics and functions,and like naturally occurring pDCs they exhibit large phenotypic and functional heterogeneity. Here,we characterize different cell subsets from in vitro pDC differentiation and identify a distinct population,which is the major producer of IFNα in response to TLR9 stimulation and display a transcriptomic profile similar to what is seen for pDCs circulating in the blood. We also investigate the possibility of rerouting subset specification during HSPCs-to-pDC differentiation by controlling gene expression of key master transcription factors (TFs). We identify TFs associated with the pDC differentiation trajectory that are essential for the development of TLR9-responsive HSPC-pDCs,and we also identify TFs that increase their frequency. In conclusion,we phenotypically and functionally characterize different cell subsets and modulate their relative frequencies by manipulating TF expression during pDC differentiation. These findings provide a deeper understanding of in vitro-differentiated pDC cultures that may spur further developments in their use as an immunomodulatory cell therapy. 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

Haploid human pluripotent stem cells (PSCs) integrate haploidy and pluripotency,providing a novel system for functional genomics and developmental research in humans. We have recently derived haploid human embryonic stem cells (ESCs) by parthenogenesis and demonstrated their wide differentiation potential and applicability for genetic screening. Because haploid cells can spontaneously become diploid,their enrichment at an early passage is key for successful derivation. In this protocol,we describe two methodologies,namely metaphase spread analysis and cell sorting,for the identification of haploid human cells within parthenogenetic ESC lines. The cell sorting approach also enables the isolation of haploid cells at low percentages,as well as the maintenance of highly enriched haploid ESC lines throughout passaging. The isolation of essentially pure populations of haploid human ESCs by this protocol requires basic PSC culture expertise and can be achieved within 4-6 weeks. View Publication

Human brain development exhibits several unique aspects,such as increased complexity and expansion of neuronal output,that have proven difficult to study in model organisms. As a result,in vitro approaches to model human brain development and disease are an intense area of research. Here we describe a recently established protocol for generating 3D brain tissue,so-called cerebral organoids,which closely mimics the endogenous developmental program. This method can easily be implemented in a standard tissue culture room and can give rise to developing cerebral cortex,ventral telencephalon,choroid plexus and retinal identities,among others,within 1-2 months. This straightforward protocol can be applied to developmental studies,as well as to the study of a variety of human brain diseases. Furthermore,as organoids can be maintained for more than 1 year in long-term culture,they also have the potential to model later events such as neuronal maturation and survival. View Publication

Human pluripotent stem cells (hPSCs) are sensitive to DNA damage and undergo rapid apoptosis compared to their differentiated progeny cells. Here,we explore the underlying mechanisms for the increased apoptotic sensitivity of hPSCs that helps to determine pluripotent stem cell fate. Apoptosis was induced by exposure to actinomycin D,etoposide,or tunicamycin,with each agent triggering a distinct apoptotic pathway. We show that hPSCs are more sensitive to all three types of apoptosis induction than are lineage-non-specific,retinoic-acid-differentiated hPSCs. Also,Bax activation and pro-apoptotic mitochondrial intermembrane space protein release,which are required to initiate the mitochondria-mediated apoptosis pathway,are more rapid in hPSCs than in retinoic-acid-differentiated hPSCs. Surprisingly,Bak and not Bax is essential for actinomycin-D-induced apoptosis in human embryonic stem cells. Finally,P53 is degraded rapidly in an ubiquitin-proteasome-dependent pathway in hPSCs at steady state but quickly accumulates and induces apoptosis when Mdm2 function is impaired. Rapid degradation of P53 ensures the survival of healthy hPSCs but avails these cells for immediate apoptosis upon cellular damage by P53 stabilization. Altogether,we provide an underlying,interconnected molecular mechanism that primes hPSCs for quick clearance by apoptosis to eliminate hPSCs with unrepaired genome alterations and preserves organismal genomic integrity during the early critical stages of human embryonic development. View Publication