J. U. Hermansen et al. (dec 2018)
Scientific reports 8 1 17651
Cryopreservation of primary B cells minimally influences their signaling responses.
Phospho flow is a powerful approach to detect cell signaling aberrations,identify biomarkers and assess pharmacodynamics,and can be performed using cryopreserved samples. The effects of cryopreservation on signaling responses and the reproducibility of phospho flow measurements are however unknown in many cell systems. Here,B lymphocytes were isolated from healthy donors and patients with the B cell malignancy chronic lymphocytic leukemia and analyzed by phospho flow using phospho-specific antibodies targeting 20 different protein epitopes. Cells were analyzed both at basal conditions and after activation of cluster of differentiation 40 (CD40) or the B cell receptor. Pharmacodynamics of the novel pathway inhibitor ibrutinib was also assessed. At all conditions,fresh cells were compared to cryopreserved cells. Minimal variation between fresh and frozen samples was detected. Reproducibility was tested by running samples from the same donors in different experiments. The results demonstrate reproducibility across different phospho flow runs and support the use of cryopreserved samples in future phospho flow studies of B lymphocytes.
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产品号#:
15024
15064
产品名:
RosetteSep™人B细胞富集抗体混合物
RosetteSep™人B细胞富集抗体混合物
G. B. Cross et al. ( 2019)
PloS one 14 5 e0216616
Impact of selective immune-cell depletion on growth of Mycobacterium tuberculosis (Mtb) in a whole-blood bactericidal activity (WBA) assay.
We investigated the contribution of host immune cells to bacterial killing in a whole-blood bactericidal activity (WBA) assay,an ex vivo model used to test efficacy of drugs against mycobacterium tuberculosis (Mtb). We performed WBA assays with immuno-magnetic depletion of specific cell types,in the presence or absence of rifampicin. Innate immune cells decreased Mtb growth in absence of drug,but appeared to diminish the cidal activity of rifampicin,possibly attributable to intracellular bacterial sequestration. Adaptive immune cells had no effect with or without drug. The WBA assay may have potential for testing adjunctive host-directed therapies acting on phagocytic cells.
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产品号#:
18000
产品名:
EasySep™磁极
C. Yacoob et al. (JUN 2018)
PLoS pathogens 14 6 e1007120
B cell clonal lineage alterations upon recombinant HIV-1 envelope immunization of rhesus macaques.
Broadly neutralizing HIV-1 antibodies (bNAbs) isolated from infected subjects display protective potential in animal models. Their elicitation by immunization is thus highly desirable. The HIV-1 envelope glycoprotein (Env) is the sole viral target of bnAbs,but is also targeted by binding,non-neutralizing antibodies. Env-based immunogens tested so far in various animal species and humans have elicited binding and autologous neutralizing antibodies but not bNAbs (with a few notable exceptions). The underlying reasons for this are not well understood despite intensive efforts to characterize the binding specificities of the elicited antibodies; mostly by employing serologic methodologies and monoclonal antibody isolation and characterization. These approaches provide limited information on the ontogenies and clonal B cell lineages that expand following Env-immunization. Thus,our current understanding on how the expansion of particular B cell lineages by Env may be linked to the development of non-neutralizing antibodies is limited. Here,in addition to serological analysis,we employed high-throughput BCR sequence analysis from the periphery,lymph nodes and bone marrow,as well as B cell- and antibody-isolation and characterization methods,to compare in great detail the B cell and antibody responses elicited in non-human primates by two forms of the clade C HIV Env 426c: one representing the full length extracellular portion of Env while the other lacking the variable domains 1,2 and 3 and three conserved N-linked glycosylation sites. The two forms were equally immunogenic,but only the latter elicited neutralizing antibodies by stimulating a more restricted expansion of B cells to a narrower set of IGH/IGK/IGL-V genes that represented a small fraction (0.003-0.02{\%}) of total B cells. Our study provides new information on how Env antigenic differences drastically affect the expansion of particular B cell lineages and supports immunogen-design efforts aiming at stimulating the expansion of cells expressing particular B cell receptors.
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Intrinsic Immunity Shapes Viral Resistance of Stem Cells.
Stem cells are highly resistant to viral infection compared to their differentiated progeny; however,the mechanism is mysterious. Here,we analyzed gene expression in mammalian stem cells and cells at various stages of differentiation. We find that,conserved across species,stem cells express a subset of genes previously classified as interferon (IFN) stimulated genes (ISGs) but that expression is intrinsic,as stem cells are refractory to interferon. This intrinsic ISG expression varies in a cell-type-specific manner,and many ISGs decrease upon differentiation,at which time cells become IFN responsive,allowing induction of a broad spectrum of ISGs by IFN signaling. Importantly,we show that intrinsically expressed ISGs protect stem cells against viral infection. We demonstrate the in vivo importance of intrinsic ISG expression for protecting stem cells and their differentiation potential during viral infection. These findings have intriguing implications for understanding stem cell biology and the evolution of pathogen resistance.
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产品号#:
02691
04434
04444
05110
05711
05712
05872
05873
18056
18056RF
72052
72054
72302
72304
72307
72308
70039
70039.1
70039.2
70039.3
70039.4
70039.5
70039.6
60062
60062BT
60062FI
60062FI.1
60062PE
60062PE.1
60045
60045AZ
60045AZ.1
60045BT
60045FI
60045FI.1
600
产品名:
StemSpan™ CD34+扩增添加物 (10X)
MethoCult™ H4434 Classic
MethoCult™ H4434 Classic
STEMdiff™定型内胚层检测试剂盒
NeuroCult™ SM1 神经添加物
CHIR99021
CHIR99021
Y-27632(二盐酸盐)
Y-27632(二盐酸盐)
Y-27632(二盐酸盐)
Y-27632(二盐酸盐)
抗人SSEA-4抗体,克隆号MC-813-70,生物素
抗人SSEA-4抗体,克隆号MC-813-70,FITC
抗人SSEA-4抗体, 克隆号MC-813-70,FITC
抗人SSEA-4抗体,克隆号MC-813-70,PE
抗人SSEA-4抗体,克隆号MC-813-70,PE
抗人CD90抗体,克隆5E10
抗人CD90抗体,克隆5E10,APC
抗人CD90抗体,克隆5E10,APC
抗人CD90抗体,克隆5E10,Biotin
抗人CD90抗体,克隆5E10,FITC
抗人CD90抗体,克隆5E10,FITC
Xu MM et al. (AUG 2017)
Immunity 47 2 363--373.e5
Dendritic Cells but Not Macrophages Sense Tumor Mitochondrial DNA for Cross-priming through Signal Regulatory Protein α Signaling.
Inhibition of cytosolic DNA sensing represents a strategy that tumor cells use for immune evasion,but the underlying mechanisms are unclear. Here we have shown that CD47-signal regulatory protein α (SIRPα) axis dictates the fate of ingested DNA in DCs for immune evasion. Although macrophages were more potent in uptaking tumor DNA,increase of DNA sensing by blocking the interaction of SIRPα with CD47 preferentially occurred in dendritic cells (DCs) but not in macrophages. Mechanistically,CD47 blockade enabled the activation of NADPH oxidase NOX2 in DCs,which in turn inhibited phagosomal acidification and reduced the degradation of tumor mitochondrial DNA (mtDNA) in DCs. mtDNA was recognized by cyclic-GMP-AMP synthase (cGAS) in the DC cytosol,contributing to type I interferon (IFN) production and antitumor adaptive immunity. Thus,our findings have demonstrated how tumor cells inhibit innate sensing in DCs and suggested that the CD47-SIRPα axis is critical for DC-driven antitumor immunity.
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