B. Westerhuis et al. (feb 2020)
Scientific reports 10 1 3152
Specific memory B cell response in humans upon infection with highly pathogenic H7N7 avian influenza virus.
H7 avian influenza viruses represent a major public health concern,and worldwide outbreaks raise the risk of a potential pandemic. Understanding the memory B cell response to avian (H7) influenza virus infection in humans could provide insights in the potential key to human infection risks. We investigated an epizootic of the highly pathogenic A(H7N7) in the Netherlands,which in 2003 led to infection of 89 persons and one fatal case. Subtype-specificity of antibodies were determined for confirmed H7N7 infected individuals (cases) (n = 19),contacts of these cases (n = 21) and a comparison group controls (n = 16),by microarray,using recombinant hemagglutinin (HA)1 proteins. The frequency and specificity of memory B cells was determined by detecting subtype-specific antibodies in the culture supernatants from in vitro stimulated oligoclonal B cell cultures,from peripheral blood of cases and controls. All cases (100{\%}) had high antibody titers specific for A(H7N7)2003 (GMT {\textgreater} 100),whereas H7-HA1 antigen binding was detected in 29{\%} of contacts and 31{\%} of controls,suggesting that some of the H7 reactivity stems from cross reactive antibodies. To unravel homotypic and heterotypic responses,the frequency and specificity of memory B cells were determined in 2 cases. Ten of 123 HA1 reactive clones isolated from the cases bound to only H7- HA1,whereas 5 bound both H7 and other HA1 antigens. We recovered at least four different epitopal reactivities,though none of the H7 reactive antibodies were able to neutralize H7 infections in vitro. Our study serologically confirms the infection with H7 avian influenza viruses,and shows that H7 infection triggers a mixture of strain -specific and cross-reactive antibodies.
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产品类型:
产品号#:
17854
17854RF
产品名:
EasySep™人CD19正选试剂盒II
RoboSep™ 人CD19正选试剂盒II
A. M. Cameron et al. ( 2019)
Nature immunology 20 4 420--432
Inflammatory macrophage dependence on NAD+ salvage is a consequence of reactive oxygen species-mediated DNA damage.
The adoption of Warburg metabolism is critical for the activation of macrophages in response to lipopolysaccharide. Macrophages stimulated with lipopolysaccharide increase their expression of nicotinamide phosphoribosyltransferase (NAMPT),a key enzyme in NAD+ salvage,and loss of NAMPT activity alters their inflammatory potential. However,the events that lead to the cells' becoming dependent on NAD+ salvage remain poorly defined. We found that depletion of NAD+ and increased expression of NAMPT occurred rapidly after inflammatory activation and coincided with DNA damage caused by reactive oxygen species (ROS). ROS produced by complex III of the mitochondrial electron-transport chain were required for macrophage activation. DNA damage was associated with activation of poly(ADP-ribose) polymerase,which led to consumption of NAD+. In this setting,increased NAMPT expression allowed the maintenance of NAD+ pools sufficient for glyceraldehyde-3-phosphate dehydrogenase activity and Warburg metabolism. Our findings provide an integrated explanation for the dependence of inflammatory macrophages on the NAD+ salvage pathway.
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Palmer DJ et al. (JUN 2016)
Molecular Therapy — Methods & Clinical Development 3 April 16039
Helper virus-mediated downregulation of transgene expression permits production of recalcitrant helper-dependent adenoviral vector
Helper-dependent adenoviral vectors (HDAd) that express certain transgene products are impossible to produce because the transgene product is toxic to the producer cells,especially when made in large amounts during vector production. Downregulating transgene expression from the HDAd during vector production is a way to solve this problem. In this report,we show that this can be accomplished by inserting the target sequence for the adenoviral VA RNAI into the 3' untranslated region of the expression cassette in the HDAd. Thus during vector production,when the producer cells are coinfected with both the helper virus (HV) and the HDAd,the VA RNAI produced by the HV will target the transgene mRNA from the HDAd via the endogenous cellular RNAi pathway. Once the HDAd is produced and purified,transduction of the target cells results in unimpeded transgene expression because of the absence of HV. This simple and universal strategy permits for the robust production of otherwise recalcitrant HDAds.
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05850
05857
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产品名:
mTeSR™1
mTeSR™1
Grö et al. (JUL 2016)
Blood
LFA-1 integrin antibodies inhibit leukocyte α4β1-mediated adhesion by intracellular signaling.
Binding of ICAM-1 (intercellular adhesion molecule-1) to the β2-integrin LFA-1 (leukocyte function associated antigen-1) is known to induce crosstalk to the α4β1 integrin. Using different LFA-1 monoclonal antibodies we have been able to study the requirement and mechanism of action for the crosstalk in considerable detail. LFA-1 activating antibodies and those inhibitory antibodies that signal to α4β1 induce phosphorylation of Thr-758 on the β2-chain,which is followed by binding of 14-3-3 proteins and signaling through the G protein exchange factor Tiam1. This results in dephosphorylation of Thr-788/789 on the β1-chain of α4β1 and loss of binding to its ligand VCAM-1 (vascular cell adhesion molecule-1). The results show that with LFA-1 antibodies,we can either 1) activate LFA-1 and inhibit α4β1,2) inhibit both LFA-1 and α4β1,3) inhibit LFA-1 but not α4β1 or 4) not affect LFA-1 or α4β1 These findings are important for the understanding of integrin regulation and for the interpretation of the effect of integrin antibodies and their use in clinical applications.
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产品类型:
产品号#:
10970
10990
产品名:
ImmunoCult™ 人CD3/CD28/CD2 T细胞激活剂
ImmunoCult™ 人CD3/CD28/CD2 T细胞激活剂
Brohawn DG et al. (AUG 2016)
PloS one 11 8 e0160520
RNAseq Analyses Identify Tumor Necrosis Factor-Mediated Inflammation as a Major Abnormality in ALS Spinal Cord.
ALS is a rapidly progressive,devastating neurodegenerative illness of adults that produces disabling weakness and spasticity arising from death of lower and upper motor neurons. No meaningful therapies exist to slow ALS progression,and molecular insights into pathogenesis and progression are sorely needed. In that context,we used high-depth,next generation RNA sequencing (RNAseq,Illumina) to define gene network abnormalities in RNA samples depleted of rRNA and isolated from cervical spinal cord sections of 7 ALS and 8 CTL samples. We aligned textgreater50 million 2X150 bp paired-end sequences/sample to the hg19 human genome and applied three different algorithms (Cuffdiff2,DEseq2,EdgeR) for identification of differentially expressed genes (DEG's). Ingenuity Pathways Analysis (IPA) and Weighted Gene Co-expression Network Analysis (WGCNA) identified inflammatory processes as significantly elevated in our ALS samples,with tumor necrosis factor (TNF) found to be a major pathway regulator (IPA) and TNF$$-induced protein 2 (TNFAIP2) as a major network hub" gene (WGCNA). Using the oPOSSUM algorithm
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产品类型:
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05850
05857
05870
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85850
85857
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85875
产品名:
mTeSR™1
mTeSR™1
Gao L et al. ( 2016)
PloS one 11 9 e0162149
31P NMR 2D Mapping of Creatine Kinase Forward Flux Rate in Hearts with Postinfarction Left Ventricular Remodeling in Response to Cell Therapy.
Utilizing a fast 31P magnetic resonance spectroscopy (MRS) 2-dimensional chemical shift imaging (2D-CSI) method,this study examined the heterogeneity of creatine kinase (CK) forward flux rate of hearts with postinfarction left ventricular (LV) remodeling. Immunosuppressed Yorkshire pigs were assigned to 4 groups: 1) A sham-operated normal group (SHAM,n = 6); 2) A 60 minutes distal left anterior descending coronary artery ligation and reperfusion (MI,n = 6); 3) Open patch group; ligation injury plus open fibrin patch over the site of injury (Patch,n = 6); and 4) Cell group,hiPSCs-cardiomyocytes,-endothelial cells,and -smooth muscle cells (2 million,each) were injected into the injured myocardium pass through a fibrin patch (Cell+Patch,n = 5). At 4 weeks,the creatine phosphate (PCr)/ATP ratio,CK forward flux rate (Flux PCr→ATP),and k constant of CK forward flux rate (kPCr→ATP) were severely decreased at border zone myocardium (BZ) adjacent to MI. Cell treatment results in significantly increase of PCr/ATP ratio and improve the value of kPCr→ATP and Flux PCr→ATP in BZ myocardium. Moreover,the BZ myocardial CK total activity and protein expression of CK mitochondria isozyme and CK myocardial isozyme were significantly reduced,but recovered in response to cell treatment. Thus,cell therapy results in improvement of BZ bioenergetic abnormality in hearts with postinfarction LV remodeling,which is accompanied by significantly improvements in BZ CK activity and CK isozyme expression. The fast 2D 31P MR CSI mapping can reliably measure the heterogeneity of bioenergetics in hearts with post infarction LV remodeling.
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产品类型:
产品号#:
05850
05857
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85850
85857
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产品名:
mTeSR™1
mTeSR™1
La Spada A et al. (DEC 2016)
The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society 64 12 739--751
Cell Line Macroarray: An Alternative High-Throughput Platform to Analyze hiPSC Lines.
In the past decade,tissue microarray (TMA) technology has evolved as an innovative tool for high-throughput proteomics analysis and mainly for biomarker validation. Similarly,enormous amount of data can be obtained from the cell line macroarray (CLMA) technology,which developed from the TMA using formalin-fixed,paraffin-embedded cell pellets. Here,we applied CLMA technology in stem cell research and in particular to identify bona fide neogenerated human induced pluripotent stem cell (hiPSC) clones suitable for down the line differentiation. All hiPSC protocols generate tens of clones,which need to be tested to determine genetically stable cell lines suitable for differentiation. Screening methods generally rely on fluorescence-activated cell sorting isolation and coverslip cell growth followed by immunofluorescence; these techniques could be cumbersome. Here,we show the application of CLMA to identify neogenerated pluripotent cell colonies and neuronal differentiated cell products. We also propose the use of the automated image analyzer,TissueQuest,as a reliable tool to quickly select the best clones,based upon the level of expression of multiple pluripotent biomarkers.
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产品类型:
产品号#:
05850
05857
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产品名:
mTeSR™1
mTeSR™1
Wei W et al. (MAY 2017)
Artificial organs 41 5 452--460
Danshen-Enhanced Cardioprotective Effect of Cardioplegia on Ischemia Reperfusion Injury in a Human-Induced Pluripotent Stem Cell-Derived Cardiomyocytes Model.
Myocardial ischemia-reperfusion (I/R) injury is unavoidable during cardioplegic arrest and open-heart surgery. Danshen is one of the most popular traditional herbal medicines in China,which has entered the Food and Drug Administration-approved phase III clinical trial. This study was aimed to develop a human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) model to mimic I/R injury and evaluate the cardioprotective effect of regular cardioplegic solution with Danshen. hiPSC-CMs were cultured with the crystalloid cardioplegic solution (Thomas group) and Thomas solution with 2 or 10 µg/mL Danshen (Thomas plus Danshen groups). The cells under normoxic culture condition served as baseline group. Then,the cells were placed in a modular incubator chamber. After 45 min hypoxia and 3 h reoxygenation,hiPSC-CMs subjected to hypoxia/reoxygenation resulted in a sharp increase of reactive oxygen species (ROS) content in Thomas group versus baseline group. Compared with the Thomas group,ROS accumulation was significant suppressed in Thomas plus Danshen groups,which might result from elevating the content of glutathione and enhanced activities of superoxide dismutase and glutathione peroxidase. The enhanced L-type Ca(2+) current in hiPSC-CMs after I/R injury was also significantly decreased by Danshen,and meanwhile intracellular Ca(2+) level was reduced and calcium overload was suppressed. Thomas plus Danshen groups also presented less irregular transients and lower apoptosis rates. As a result,Danshen could improve antioxidant and calcium handling in cardiomyocytes during I/R and lead to reduced arrhythmia events and apoptosis rates. hiPSC-CMs model offered a platform for the future translational study of the cardioplegia.
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产品类型:
产品号#:
05850
05857
05870
05875
85850
85857
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产品名:
mTeSR™1
mTeSR™1
Guo D et al. (JAN 2017)
Stem cell research 18 67--69
Creating a patient carried Men1 gene point mutation on wild type iPSCs locus mediated by CRISPR/Cas9 and ssODN.
A patient specific point mutation (c.1288GtextgreaterT) of Men1 gene was introduced into wide type iPSC line with CRISPR/Cas9 and single-stranded donor oligonucleotides carrying the mutation. The mutated iPSC line has a heterozygous c.1288GtextgreaterT mutation on exon-9 of Men1 that was confirmed by sequencing analysis. The karyotype of this line was normal and the pluripotency was demonstrated by its ability to differentiate into three germ layers. These artificially created Men1 mutation in wild type iPSC line will help to dissect out the molecular basis of two patients carried the same mutation from one family who were differentially represented hypoglycemia.
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Zhou L et al. (AUG 2002)
Journal of molecular biology 321 4 591--9
Zebularine: a novel DNA methylation inhibitor that forms a covalent complex with DNA methyltransferases.
Mechanism-based inhibitors of enzymes,which mimic reactive intermediates in the reaction pathway,have been deployed extensively in the analysis of metabolic pathways and as candidate drugs. The inhibition of cytosine-[C5]-specific DNA methyltransferases (C5 MTases) by oligodeoxynucleotides containing 5-azadeoxycytidine (AzadC) and 5-fluorodeoxycytidine (FdC) provides a well-documented example of mechanism-based inhibition of enzymes central to nucleic acid metabolism. Here,we describe the interaction between the C5 MTase from Haemophilus haemolyticus (M.HhaI) and an oligodeoxynucleotide duplex containing 2-H pyrimidinone,an analogue often referred to as zebularine and known to give rise to high-affinity complexes with MTases. X-ray crystallography has demonstrated the formation of a covalent bond between M.HhaI and the 2-H pyrimidinone-containing oligodeoxynucleotide. This observation enables a comparison between the mechanisms of action of 2-H pyrimidinone with other mechanism-based inhibitors such as FdC. This novel complex provides a molecular explanation for the mechanism of action of the anti-cancer drug zebularine.
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