Wellington M et al. (DEC 2003)
Infection and immunity 71 12 7228--31
Enhanced phagocytosis of Candida species mediated by opsonization with a recombinant human antibody single-chain variable fragment.
Specific antibody opsonization significantly enhances the level of phagocytosis of Candida in the absence of complement. Furthermore,we have described a system using a recombinant human antibody single-chain variable fragment that allows a comparative study of phagocytosis of multiple Candida species opsonized via a common antigen.
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MiRNA-Mediated Regulation of the SWI/SNF Chromatin Remodeling Complex Controls Pluripotency and Endodermal Differentiation in Human ESCs.
MicroRNAs and chromatin remodeling complexes represent powerful epigenetic mechanisms that regulate the pluripotent state. miR-302 is a strong inducer of pluripotency,which is characterized by a distinct chromatin architecture. This suggests that miR-302 regulates global chromatin structure; however,a direct relationship between miR-302 and chromatin remodelers has not been established. Here,we provide data to show that miR-302 regulates Brg1 chromatin remodeling complex composition in human embryonic stem cells (hESCs) through direct repression of the BAF53a and BAF170 subunits. With the subsequent overexpression of BAF170 in hESCs,we show that miR-302's inhibition of BAF170 protein levels can affect the expression of genes involved in cell proliferation. Furthermore,miR-302-mediated repression of BAF170 regulates pluripotency by positively influencing mesendodermal differentiation. Overexpression of BAF170 in hESCs led to biased differentiation toward the ectoderm lineage during EB formation and severely hindered directed definitive endoderm differentiation. Taken together,these data uncover a direct regulatory relationship between miR-302 and the Brg1 chromatin remodeling complex that controls gene expression and cell fate decisions in hESCs and suggests that similar mechanisms are at play during early human development.
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产品类型：
产品号#：
05110
产品名：
STEMdiff™定型内胚层检测试剂盒
Li W et al. (DEC 2009)
Stem cells (Dayton,Ohio) 27 12 2992--3000
Generation of human-induced pluripotent stem cells in the absence of exogenous Sox2.
Induced pluripotent stem cell technology has attracted enormous interest for potential application in regenerative medicine. Here,we report that a specific glycogen synthase kinase 3 (GSK-3) inhibitor,CHIR99021,can induce the reprogramming of mouse embryonic fibroblasts transduced by only two factors,Oct4 and Klf4. When combined with Parnate (also named tranylcypromine),an inhibitor of lysine-specific demethylase 1,CHIR99021 can cause the reprogramming of human primary keratinocyte transduced with the two factors,Oct4 and Klf4. To our knowledge,this is the first time that human iPS cells have been generated from somatic cells without exogenous Sox2 expression. Our studies suggest that the GSK-3 inhibitor might have a general application to replace transcription factors in both mouse and human reprogramming.
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产品类型：
产品号#：
72272
72274
产品名：
Fang Y et al. (JUN 2010)
Journal of leukocyte biology 87 6 1019--28
Comparison of sensitivity of Th1, Th2, and Th17 cells to Fas-mediated apoptosis.
Following activation through the TCR,CD4+ T cells can differentiate into three major subsets: Th1,Th2,and Th17 cells. IL-17-secreting Th17 cells play an important role in the pathogenesis of several autoimmune diseases and in immune responses to pathogens,but little is known about the regulation of apoptosis in Th17 cells. In this study,the sensitivity of in vitro-polarized Th1,Th2,and Th17 cells to Fas-mediated apoptosis was compared directly by different methods. The order of sensitivity of T cell subsets to Fas-mediated apoptosis is: Th1 textgreater Th17 textgreater Th2. The greater sensitivity of Th17 cells to Fas-mediated apoptosis compared with Th2 cells correlated with their higher expression of FasL and comparable expression of the antiapoptotic molecule FLIP. The decreased sensitivity of Th17 compared with Th1 cells correlated with the higher expression of FLIP by Th17 cells. Transgenic overexpression of FLIP in T cells protected all three subsets from Fas-mediated apoptosis. These findings provide new knowledge for understanding how survival of different subsets of T cells is regulated.
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产品类型：
产品号#：
18554
18554RF
18564
18564RF
产品名：
Li Y et al. (MAY 2010)
Clinical cancer research : an official journal of the American Association for Cancer Research 16 9 2580--90
Sulforaphane, a dietary component of broccoli/broccoli sprouts, inhibits breast cancer stem cells.
PURPOSE: The existence of cancer stem cells (CSCs) in breast cancer has profound implications for cancer prevention. In this study,we evaluated sulforaphane,a natural compound derived from broccoli/broccoli sprouts,for its efficacy to inhibit breast CSCs and its potential mechanism. EXPERIMENTAL DESIGN: Aldefluor assay and mammosphere formation assay were used to evaluate the effect of sulforaphane on breast CSCs in vitro. A nonobese diabetic/severe combined immunodeficient xenograft model was used to determine whether sulforaphane could target breast CSCs in vivo,as assessed by Aldefluor assay,and tumor growth upon cell reimplantation in secondary mice. The potential mechanism was investigated using Western blotting analysis and beta-catenin reporter assay. RESULTS: Sulforaphane (1-5 micromol/L) decreased aldehyde dehydrogenase-positive cell population by 65% to 80% in human breast cancer cells (P textless 0.01) and reduced the size and number of primary mammospheres by 8- to 125-fold and 45% to 75% (P textless 0.01),respectively. Daily injection with 50 mg/kg sulforaphane for 2 weeks reduced aldehyde dehydrogenase-positive cells by textgreater50% in nonobese diabetic/severe combined immunodeficient xenograft tumors (P = 0.003). Sulforaphane eliminated breast CSCs in vivo,thereby abrogating tumor growth after the reimplantation of primary tumor cells into the secondary mice (P textless 0.01). Western blotting analysis and beta-catenin reporter assay showed that sulforaphane downregulated the Wnt/beta-catenin self-renewal pathway. CONCLUSIONS: Sulforaphane inhibits breast CSCs and downregulates the Wnt/beta-catenin self-renewal pathway. These findings support the use of sulforaphane for the chemoprevention of breast cancer stem cells and warrant further clinical evaluation.
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产品类型：
产品号#：
01700
01705
01702
产品名：
ALDEFLUOR™ 试剂盒
ALDEFLUOR™ DEAB试剂
ALDEFLUOR™测定缓冲液
Blackmore DG et al. (JAN 2012)
PloS one 7 11 e49912
GH mediates exercise-dependent activation of SVZ neural precursor cells in aged mice.
Here we demonstrate,both in vivo and in vitro,that growth hormone (GH) mediates precursor cell activation in the subventricular zone (SVZ) of the aged (12-month-old) brain following exercise,and that GH signaling stimulates precursor activation to a similar extent to exercise. Our results reveal that both addition of GH in culture and direct intracerebroventricular infusion of GH stimulate neural precursor cells in the aged brain. In contrast,no increase in neurosphere numbers was observed in GH receptor null animals following exercise. Continuous infusion of a GH antagonist into the lateral ventricle of wild-type animals completely abolished the exercise-induced increase in neural precursor cell number. Given that the aged brain does not recover well after injury,we investigated the direct effect of exercise and GH on neural precursor cell activation following irradiation. This revealed that physical exercise as well as infusion of GH promoted repopulation of neural precursor cells in irradiated aged animals. Conversely,infusion of a GH antagonist during exercise prevented recovery of precursor cells in the SVZ following irradiation.
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产品类型：
产品号#：
05700
05701
05702
产品名：
NeuroCult™ 基础培养基(小鼠&大鼠)
NeuroCult™ 扩增添加物 (小鼠&大鼠)
NeuroCult™ 扩增试剂盒 (小鼠&大鼠)
Wang Q et al. (OCT 2016)
Biomaterials 105 52--65
Functional engineered human cardiac patches prepared from nature's platform improve heart function after acute myocardial infarction.
With the advent of induced pluripotent stem cells and directed differentiation techniques,it is now feasible to derive individual-specific cardiac cells for human heart tissue engineering. Here we report the generation of functional engineered human cardiac patches using human induced pluripotent stem cells-derived cardiac cells and decellularized natural heart ECM as scaffolds. The engineered human cardiac patches can be tailored to any desired size and shape and exhibited normal contractile and electrical physiology in vitro. Further,when patching on the infarct area,these patches improved heart function of rats with acute myocardial infarction in vivo. These engineered human cardiac patches can be of great value for normal and disease-specific heart tissue engineering,drug screening,and meet the demands for individual-specific heart tissues for personalized regenerative therapy of myocardial damages in the future.
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产品类型：
产品号#：
05850
05857
05870
05875
85850
85857
85870
85875
产品名：
mTeSR™1
mTeSR™1
Ng WL et al. (JAN 2014)
Cell death & disease 5 1 e1024
OCT4 as a target of miR-34a stimulates p63 but inhibits p53 to promote human cell transformation
Human cell transformation is a key step for oncogenic development,which involves multiple pathways; however,the mechanism remains unclear. To test our hypothesis whether cell oncogenic transformation shares some mechanisms with the process of reprogramming non-stem cells to induced pluripotent stem cells (iPSC),we studied the relationship among the key factors for promoting or inhibiting iPSC in radiation-transformed human epithelial cell lines derived from different tissues (lung,breast and colon). We unexpectedly found that p63 and OCT4 were highly expressed (accompanied by low expressed p53 and miR-34a) in all transformed cell lines examined when compared with their non-transformed counterparts. We further elucidated the relationship of these factors: the 3p strand of miR-34a directly targeted OCT4 by binding to the 3′ untranslated region (3′-UTR) of OCT4 and,OCT4,in turn,stimulated p63 but inhibited p53 expression by binding to a specific region of the p63 or p53 promoter. Moreover,we revealed that the effects of OCT4 on promoting cell oncogenic transformation were by affecting p63 and p53. These results support that a positive loop exists in human cells: OCT4 upregulation as a consequence of inhibition of miR-34a,promotes p63 but suppresses p53 expression,which further stimulates OCT4 upregulation by downregulating miR-34a. This functional loop contributes significantly to cell transformation and,most likely,also to the iPSC process.
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Toh Y-CC et al. (MAY 2015)
Biomaterials 50 1 87--97
Modulation of integrin and E-cadherin-mediated adhesions to spatially control heterogeneity in human pluripotent stem cell differentiation.
Heterogeneity in human pluripotent stem cell (PSC) fates is partially caused by mechanical asymmetry arising from spatial polarization of cell-cell and cell-matrix adhesions. Independent studies have shown that integrin and E-cadherin adhesions promote opposing differentiation and pluripotent fates respectively although their crosstalk mechanism in modulating cell fate heterogeneity remains unknown. Here,we demonstrated that spatial polarization of integrin and E-cadherin adhesions in a human PSC colony compete to recruit Rho-ROCK activated myosin II to different localities to pattern pluripotent-differentiation decisions,resulting in spatially heterogeneous colonies. Cell micropatterning was used to modulate the spatial polarization of cell adhesions,which enabled us to prospectively determine localization patterns of activated myosin II and mesoendoderm differentiation. Direct inhibition of Rho-ROCK-myosin II activation phenocopied E-cadherin rather than integrin inhibition to form uniformly differentiated colonies. This indicated that E-cadherin was the primary gatekeeper to differentiation progression. This insight allows for biomaterials to be tailored for human PSC maintenance or differentiation with minimal heterogeneity.
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Integrated Analysis of Contractile Kinetics, Force Generation, and Electrical Activity in Single Human Stem Cell-Derived Cardiomyocytes.
The quantitative analysis of cardiomyocyte function is essential for stem cell-based approaches for the in vitro study of human cardiac physiology and pathophysiology. We present a method to comprehensively assess the function of single human pluripotent stem cell-derived cardiomyocyte (hPSC-CMs) through simultaneous quantitative analysis of contraction kinetics,force generation,and electrical activity. We demonstrate that statistical analysis of movies of contracting hPSC-CMs can be used to quantify changes in cellular morphology over time and compute contractile kinetics. Using a biomechanical model that incorporates substrate stiffness,we calculate cardiomyocyte force generation at single-cell resolution and validate this approach with conventional traction force microscopy. The addition of fluorescent calcium indicators or membrane potential dyes allows the simultaneous analysis of contractility and calcium handling or action potential morphology. Accordingly,our approach has the potential for broad application in the study of cardiac disease,drug discovery,and cardiotoxicity screening.
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产品类型：
产品号#：
05850
05857
05870
05875
85850
85857
85870
85875
产品名：
mTeSR™1
mTeSR™1
Crist SA et al. (APR 2008)
Blood 111 7 3553--61
Nuclear factor of activated T cells (NFAT) mediates CD154 expression in megakaryocytes.
Platelets are an abundant source of CD40 ligand (CD154),an immunomodulatory and proinflammatory molecule implicated in the onset and progression of several inflammatory diseases,including systemic lupus erythematosus (SLE),diabetes,and cardiovascular disease. Heretofore considered largely restricted to activated T cells,we initiated studies to investigate the source and regulation of platelet-associated CD154. We found that CD154 is abundantly expressed in platelet precursor cells,megakaryocytes. We show that CD154 is expressed in primary human CD34+ and murine hematopoietic precursor cells only after cytokine-driven megakaryocyte differentiation. Furthermore,using several established megakaryocyte-like cells lines,we performed promoter analysis of the CD154 gene and found that NFAT,a calcium-dependent transcriptional regulator associated with activated T cells,mediated both differentiation-dependent and inducible megakaryocyte-specific CD154 expression. Overall,these data represent the first investigation of the regulation of a novel source of CD154 and suggests that platelet-associated CD154 can be biochemically modulated.
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产品类型：
产品号#：
09600
09650
产品名：
StemSpan™ SFEM
StemSpan™ SFEM
Zhao S et al. (APR 2012)
Cancer letters 317 2 192--198
Activation of the aryl hydrocarbon receptor represses mammosphere formation in MCF-7 cells.
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor. Recent studies have reported the anti-tumor effects of the AhR in breast cancer. In this study,we investigated the anti-tumor effect of AhR activation based on the cancer stem cell hypothesis. We show that AhR activation suppressed mammosphere formation of MCF-7 cells and decreased the proportion of cells with high ALDH-1 (aldehyde dehydrogenase 1) activity. In addition,we also demonstrate that AhR activation regulates self-renewal signaling by down-regulating Wnt/$$-catenin and Notch.
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EasySep™小鼠TIL（CD45）正选试剂盒
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