Jones RB et al. (SEP 2009)
Journal of virology 83 17 8722--32
Human immunodeficiency virus type 1 escapes from interleukin-2-producing CD4+ T-cell responses without high-frequency fixation of mutations.
The presence of interleukin-2 (IL-2)-producing human immunodeficiency virus type 1 (HIV-1)-specific CD4(+) T-cell responses has been associated with the immunological control of HIV-1 replication; however,the causal relationship between these factors remains unclear. Here we show that IL-2-producing HIV-1-specific CD4(+) T cells can be cloned from acutely HIV-1-infected individuals. Despite the early presence of these cells,each of the individuals in the present study exhibited progressive disease,with one individual showing rapid progression. In this rapid progressor,three IL-2-producing HIV-1 Gag-specific CD4(+) T-cell responses were identified and mapped to the following optimal epitopes: HIVWASRELER,REPRGSDIAGT,and FRDYVDRFYKT. Responses to these epitopes in peripheral blood mononuclear cells were monitored longitudinally to textgreater1 year postinfection,and contemporaneous circulating plasma viruses were sequenced. A variant of the FRDYVDRFYKT epitope sequence,FRDYVDQFYKT,was observed in 1/21 plasma viruses sequenced at 5 months postinfection and 1/10 viruses at 7 months postinfection. This variant failed to stimulate the corresponding CD4(+) T-cell clone and thus constitutes an escape mutant. Responses to each of the three Gag epitopes were rapidly lost,and this loss was accompanied by a loss of antigen-specific cells in the periphery as measured by using an FRDYVDRFYKT-presenting major histocompatibility complex class II tetramer. Highly active antiretroviral therapy was associated with the reemergence of FRDYVDRFYKT-specific cells by tetramer. Thus,our data support that IL-2-producing HIV-1-specific CD4(+) T-cell responses can exert immune pressure during early HIV-1 infection but that the inability of these responses to enforce enduring control of viral replication is related to the deletion and/or dysfunction of HIV-1-specific CD4(+) T cells rather than to the fixation of escape mutations at high frequencies.
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产品类型：
产品号#：
19052
19052RF
产品名：
EasySep™人CD4+ T细胞富集试剂盒
RoboSep™ 人CD4+ T细胞富集试剂盒含滤芯吸头
Costantini C et al. (JAN 2009)
Immunobiology 214 9-10 828--34
On the co-purification of 6-sulfo LacNAc(+) dendritic cells (slanDC) with NK cells enriched from human blood.
The ability of NK cells to directly recognize pathogens and be activated via Toll-like receptors (TLR) is increasingly recognized. Nevertheless,controversial results on the NK cell ability to be directly activated by lipopolysaccharide (LPS),the ligand of TLR4,have been recently reported. To start elucidating the reasons explaining the contrasting observations of the literature,we focused on the potential role of currently used NK cell purification procedures to condition putative NK cell responsiveness to LPS. To do so,human NK cells were isolated by negative selection,using three different commercial kits,to be comparatively evaluated for the production of IFNgamma in response to ultra-pure LPS and/or IL-2. Despite the lack of surface TLR4,we found that two out of the three NK cell-enriched populations released IFNgamma (and one of the two,IL-12p70 as well) in response to the LPS plus IL-2 combination,whereas the last one did not. However,the two LPS plus IL-2-responsive NK cell populations were found variably contaminated with 6-sulfo LacNAc(+) dendritic cells (slanDC),demonstrated responsible for triggering,via the production of IL-12p70 in response to LPS,the release of IFNgamma by IL-2-stimulated NK cells. Accordingly,slanDC depletion completely abrogated the capacity to produce both IL-12p70 and IFNgamma in response to LPS plus IL-2 by slanDC-containing NK cells. Taken together,our data uncover that two commercially available kits,specifically designed to isolate NK cells by negative selection,also co-purify variable amounts of slanDC. The latter cells may dramatically affect the outcome of experiments carried on to evaluate NK cell responsiveness to TLR agonists such as LPS.
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产品类型：
产品号#：
19055
19055RF
产品名：
EasySep™人NK细胞富集试剂盒
RoboSep™ 人NK细胞富集试剂盒含滤芯吸头
Billerbeck E et al. (FEB 2010)
Proceedings of the National Academy of Sciences of the United States of America 107 7 3006--11
Analysis of CD161 expression on human CD8+ T cells defines a distinct functional subset with tissue-homing properties.
CD8(+) T lymphocytes play a key role in host defense,in particular against important persistent viruses,although the critical functional properties of such cells in tissue are not fully defined. We have previously observed that CD8(+) T cells specific for tissue-localized viruses such as hepatitis C virus express high levels of the C-type lectin CD161. To explore the significance of this,we examined CD8(+)CD161(+) T cells in healthy donors and those with hepatitis C virus and defined a population of CD8(+) T cells with distinct homing and functional properties. These cells express high levels of CD161 and a pattern of molecules consistent with type 17 differentiation,including cytokines (e.g.,IL-17,IL-22),transcription factors (e.g.,retinoic acid-related orphan receptor gamma-t,P = 6 x 10(-9); RUNX2,P = 0.004),cytokine receptors (e.g.,IL-23R,P = 2 x 10(-7); IL-18 receptor,P = 4 x 10(-6)),and chemokine receptors (e.g.,CCR6,P = 3 x 10(-8); CXCR6,P = 3 x 10(-7); CCR2,P = 4 x 10(-7)). CD161(+)CD8(+) T cells were markedly enriched in tissue samples and coexpressed IL-17 with high levels of IFN-gamma and/or IL-22. The levels of polyfunctional cells in tissue was most marked in those with mild disease (P = 0.0006). These data define a T cell lineage that is present already in cord blood and represents as many as one in six circulating CD8(+) T cells in normal humans and a substantial fraction of tissue-infiltrating CD8(+) T cells in chronic inflammation. Such cells play a role in the pathogenesis of chronic hepatitis and arthritis and potentially in other infectious and inflammatory diseases of man.
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产品类型：
产品号#：
19053
19053RF
产品名：
EasySep™人CD8+ T细胞富集试剂盒
RoboSep™ 人CD8+ T细胞富集试剂盒含滤芯吸头
Crane CA et al. (JAN 2010)
Neuro-oncology 12 1 7--13
TGF-beta downregulates the activating receptor NKG2D on NK cells and CD8+ T cells in glioma patients.
The activating receptor NKG2D,expressed by natural killer (NK) cells and CD8(+) T cells,has a role in the specific killing of transformed cells. We examined NKG2D expression in patients with glioblastoma multiforme and found that NKG2D was downregulated on NK cells and CD8(+) T cells. Expression of NKG2D on lymphocytes significantly increased following tumor resection and correlated with an increased ability to kill NKG2D ligand-positive tumor targets. Despite the presence of soluble NKG2D ligands in the sera of glioblastoma patients,NKG2D downregulation was primarily caused by tumor-derived tumor growth factor-beta,suggesting that blocking of this cytokine may have therapeutic benefit.
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产品类型：
产品号#：
19055
19055RF
产品名：
EasySep™人NK细胞富集试剂盒
RoboSep™ 人NK细胞富集试剂盒含滤芯吸头
Krummen M et al. (JUL 2010)
Journal of leukocyte biology 88 1 189--99
Release of IL-12 by dendritic cells activated by TLR ligation is dependent on MyD88 signaling, whereas TRIF signaling is indispensable for TLR synergy.
Recently,it has been shown that certain combinations of TLR ligands act in synergy to induce the release of IL-12 by DCs. In this study,we sought to define the critical parameters underlying TLR synergy. Our data show that TLR ligands act synergistically if MyD88- and TRIF-dependent ligands are combined. TLR4 uses both of these adaptor molecules,thus activation via TLR4 proved to be a synergistic event on its own. TLR synergy did not affect all aspects of DC activation but enhanced primarily the release of certain cytokines,particularly IL-12,whereas the expression of costimulatory molecules remained unchanged. Consequently,synergistic activation of DC did not affect their ability to induce T cell proliferation but resulted in T(H)1-biased responses in vitro and in vivo. Furthermore,we examined the impact of TLR ligand combinations on primary DC in vitro but observed only modest effects with a combination of CpG + Poly (I:C). However,noticeable synergy in terms of IL-12 production by DCs was detectable in vivo after systemic administration of CpG + Poly (I:C). Finally,we show that synergy is partially dependent on IFNAR signaling but does not require the release of IFNs to the enviroment,suggesting an autocrine action of type I IFNs.
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产品类型：
产品号#：
18752
18752RF
21000
20119
20155
18758
18758RF
18768
18768RF
产品名：
RoboSep™- S
RoboSep™ 吸头组件抛光剂
RoboSep™分选管套装（9个塑料管）
Mihalcik SA et al. (JUL 2010)
Journal of immunology (Baltimore,Md. : 1950) 185 2 1045--54
The structure of the TNFRSF13C promoter enables differential expression of BAFF-R during B cell ontogeny and terminal differentiation.
The B cell-activating factor of the TNF family receptor (BAFF-R),encoded by the TNFRSF13C gene,is critically important for transitional B cell survival to maturity. Thus,ligation of BAFF-R by BAFF delivers a potent survival signal. Reports implicating the BAFF/BAFF-R signaling axis in the pathogenesis of autoimmune human diseases and B lineage malignancies have largely prompted studies focusing on BAFF expression; however,there is an equally critical need to better understand BAFF-R expression. Initial BAFF-R expression,although characterized in murine B cells,has not yet been reported in human B lymphopoiesis. In this study,we first demonstrate that BAFF-R expression is absent from early precursors and is acquired by bone marrow B cells newly expressing the BCR. We next focused on identifying the specific genomic region that controls BAFF-R expression in mature B cells (i.e.,the TNFRSF13C promoter). To accomplish this,we used in silico tools examining interspecies genomic conservation in conjunction with reporter constructs transfected into malignant B and plasma cell lines. DNase protection assays using nuclear extracts from BAFF-R-expressing cells suggested potential regulatory sites,which allowed the generation of EMSA probes that bound NFs specific to BAFF-R-expressing cells. With a more stringent analysis of interspecies homology,these assays identified a site at which a single nucleotide substitution could distinctly impact promoter activity. Finally,chromatin immunoprecipitation assays revealed the in vivo binding of the specific transcription factor c-Rel to the most proximal genomic region,and c-Rel small interfering RNA transfections in BAFF-R-expressing lines demonstrated a coincident knockdown of both c-Rel and BAFF-R mRNA.
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产品类型：
产品号#：
21000
20119
20155
19054
19054RF
产品名：
RoboSep™- S
RoboSep™ 吸头组件抛光剂
RoboSep™分选管套装（9个塑料管）
EasySep™人B细胞富集试剂盒
RoboSep™ 人B细胞富集试剂盒含滤芯吸头
Chun T-W et al. (NOV 2010)
AIDS (London,England) 24 18 2803--8
Rebound of plasma viremia following cessation of antiretroviral therapy despite profoundly low levels of HIV reservoir: implications for eradication.
OBJECTIVES: Sustained suppression of plasma viremia in HIV-infected individuals is attainable with antiretroviral therapy (ART); however,eradication of virus that would allow discontinuation of ART has been hampered by the persistence of HIV reservoirs. It is of great interest to identify individuals who had received ART for prolonged periods of time with extremely low or undetectable HIV reservoirs and monitor plasma viremia following discontinuation of therapy. METHODS: We measured the size of HIV reservoirs in CD4(+) T cells of individuals on long-term ART and monitored plasma viremia following cessation of ART in one individual with an exceptionally low viral burden after a decade of therapy. RESULTS: We demonstrated undetectable levels of HIV DNA in the blood of eight of 45 infected individuals on long-term ART. Among those eight individuals,the frequency of cells carrying infectious virus was significantly lower in those who initiated ART during the early versus the chronic phase of infection. One individual with undetectable HIV DNA in both blood and tissue and a profoundly low level of infectious virus experienced plasma viral rebound 50 days following discontinuation of ART. CONCLUSIONS: Our data suggest that a significant reduction in the size of viral reservoirs may be achievable in selected individuals who initiate standard ART early in infection. However,given re-emergence of plasma viremia in an individual with an extraordinarily low viral burden,therapeutic strategies aimed at specifically targeting these extremely rare HIV-infected cells with novel interventions may be necessary in order to achieve eradication of virus.
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产品类型：
产品号#：
19052
19052RF
21000
20119
20155
产品名：
EasySep™人CD4+ T细胞富集试剂盒
RoboSep™ 人CD4+ T细胞富集试剂盒含滤芯吸头
RoboSep™- S
RoboSep™ 吸头组件抛光剂
RoboSep™分选管套装（9个塑料管）
Zhang L-Z et al. (JUN 2010)
Zhonghua xue ye xue za zhi = Zhonghua xueyexue zazhi 31 6 398--402
[In vitro effects of anti-CD44 monoclonal antibody on the adhesion and migration of chronic myeloid leukemia stem cells.]
OBJECTIVE: To explore the effects of anti-CD44 monoclonal antibody-IM7 on the in vitro adhesion and migration of chronic myeloid leukemia stem cell (CML-LSC) and its mechanism. METHODS: CD34(+)CD38(-)CD123(+) leukemic stem cells (LSC) from 20 newly-diagnosed chronic myeloid leukemia (CML) patients BM cells and CD34(+)CD38(-) hematopoietic stem cells (HSC) from 20 full-term newborn cord blood cells were isolated with EasySep(TM) magnet beads. The CD44 expression of the LSC and HSC was detected by flow cytometry (FCM),and the adhesion and migration ability of the LSC and HSC pre- and post-incubated with IM7 in vitro by MTT assay and transendothelial migration assay,respectively. RESULTS: (1) After incubated with IM7,the LSC and HSC CD44 expression rates were (86.60 ± 2.10)% vs. (25.40 ± 1.70)% (P textless 0.05),respectively. (2) The adhesive ability of the LSC to endothelial cells was decreased markedly after incubated with IM7,the OD value (A(570)) changing from pre-incubation of (0.62 ± 0.11) to post-incubation of (0.34 ± 0.07),while there was little change of A(570) in the HSC group. (3) The migration ability of the LSC group was inhibited evidently after incubated with IM7,the inhibition rate being 46% ∼ 63%,while little change of that in HSC group was detected. (4) The adhesive ability of the LSC group to marrow stromal cells was decreased markedly after incubated with IM7,while little change was found in that of HSC group. CONCLUSION: The anti-CD44 monoclonal antibody-IM7 can effectively inhibit the adhesion and migration abilities of the LSC in vitro,which might provide a theoretical evidence for targeting therapy.
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Chang M-J et al. (DEC 2010)
Cancer research 70 24 10234--42
Histone H3 lysine 79 methyltransferase Dot1 is required for immortalization by MLL oncogenes.
Chimeric oncoproteins resulting from fusion of MLL to a wide variety of partnering proteins cause biologically distinctive and clinically aggressive acute leukemias. However,the mechanism of MLL-mediated leukemic transformation is not fully understood. Dot1,the only known histone H3 lysine 79 (H3K79) methyltransferase,has been shown to interact with multiple MLL fusion partners including AF9,ENL,AF10,and AF17. In this study,we utilize a conditional Dot1l deletion model to investigate the role of Dot1 in hematopoietic progenitor cell immortalization by MLL fusion proteins. Western blot and mass spectrometry show that Dot1-deficient cells are depleted of the global H3K79 methylation mark. We find that loss of Dot1 activity attenuates cell viability and colony formation potential of cells immortalized by MLL oncoproteins but not by the leukemic oncoprotein E2a-Pbx1. Although this effect is most pronounced for MLL-AF9,we find that Dot1 contributes to the viability of cells immortalized by other MLL oncoproteins that are not known to directly recruit Dot1. Cells immortalized by MLL fusions also show increased apoptosis,suggesting the involvement of Dot1 in survival pathways. In summary,our data point to a pivotal requirement for Dot1 in MLL fusion protein-mediated leukemogenesis and implicate Dot1 as a potential therapeutic target.
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产品类型：
产品号#：
03234
18757
18757RF
产品名：
MethoCult™M3234
EasySep™小鼠CD117（cKIT）正选试剂盒
RoboSep™ 小鼠CD117（cKIT）正选试剂盒含滤芯吸头
Allantaz F et al. ( 2012)
PloS one 7 1 e29979
Expression profiling of human immune cell subsets identifies miRNA-mRNA regulatory relationships correlated with cell type specific expression.
Blood consists of different cell populations with distinct functions and correspondingly,distinct gene expression profiles. In this study,global miRNA expression profiling was performed across a panel of nine human immune cell subsets (neutrophils,eosinophils,monocytes,B cells,NK cells,CD4 T cells,CD8 T cells,mDCs and pDCs) to identify cell-type specific miRNAs. mRNA expression profiling was performed on the same samples to determine if miRNAs specific to certain cell types down-regulated expression levels of their target genes. Six cell-type specific miRNAs (miR-143; neutrophil specific,miR-125; T cells and neutrophil specific,miR-500; monocyte and pDC specific,miR-150; lymphoid cell specific,miR-652 and miR-223; both myeloid cell specific) were negatively correlated with expression of their predicted target genes. These results were further validated using an independent cohort where similar immune cell subsets were isolated and profiled for both miRNA and mRNA expression. miRNAs which negatively correlated with target gene expression in both cohorts were identified as candidates for miRNA/mRNA regulatory pairs and were used to construct a cell-type specific regulatory network. miRNA/mRNA pairs formed two distinct clusters in the network corresponding to myeloid (nine miRNAs) and lymphoid lineages (two miRNAs). Several myeloid specific miRNAs targeted common genes including ABL2,EIF4A2,EPC1 and INO80D; these common targets were enriched for genes involved in the regulation of gene expression (ptextless9.0E-7). Those miRNA might therefore have significant further effect on gene expression by repressing the expression of genes involved in transcriptional regulation. The miRNA and mRNA expression profiles reported in this study form a comprehensive transcriptome database of various human blood cells and serve as a valuable resource for elucidating the role of miRNA mediated regulation in the establishment of immune cell identity.
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产品类型：
产品号#：
17953
17953RF
18058
18058RF
19061
19061RF
19062
19062RF
19257
19257RF
19055
19055RF
100-0710
产品名：
EasySep™人CD8+ T细胞分选试剂盒
RoboSep™ 人CD8+ T细胞分选试剂盒
EasySep™人髓样DC富集试剂盒
RoboSep™ 人髓样DC富集试剂盒
EasySep™人浆细胞样DC富集试剂盒
RoboSep™ 人浆细胞样DC富集试剂盒含滤芯吸头
EasySep™人NK细胞富集试剂盒
RoboSep™ 人NK细胞富集试剂盒含滤芯吸头
EasySep™人CD8+ T细胞分选试剂盒
Machmach K et al. (APR 2012)
Journal of virology 86 8 4245--52
Plasmacytoid dendritic cells reduce HIV production in elite controllers.
HIV elite controllers (EC) are a rare group of HIV-infected patients who are able to maintain undetectable viral loads during a long period of time in the absence of antiretroviral treatment. Adaptive immunity and host genetic factors,although implicated,do not entirely explain this phenomenon. On the other hand,plasmacytoid dendritic cells (pDCs) are the principal type I interferon (IFN) producers in response to viral infection,and it is unknown whether pDCs are involved in the control of HIV infection in EC. In our study,we analyzed peripheral pDC levels and IFN-α production by peripheral blood mononuclear cells (PBMCs) in EC compared to other groups of HIV-infected patients,the ability of pDCs to reduce HIV production in vitro,and the mechanisms potentially involved. We showed preserved pDC counts and IFN-α production in EC. We also observed a higher capacity of pDCs from EC to reduce HIV production and to induce T cell apoptosis,whereas pDCs from viremic patients barely responded without previous Toll-like receptor 9 (TLR-9) stimulus. The preserved functionality of pDCs from EC to reduce viral production may be one of the mechanisms involved in the control of HIV viremia in these subjects. These results demonstrate the importance of innate immunity in HIV pathogenesis,and an understanding of pDC mechanisms would be helpful for the design of new therapies.
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产品类型：
产品号#：
15022
15062
19062
19062RF
17977
17977RF
产品名：
RosetteSep™人CD4+ T细胞富集抗体混合物
RosetteSep™人CD4+ T细胞富集抗体混合物
EasySep™人浆细胞样DC富集试剂盒
RoboSep™ 人浆细胞样DC富集试剂盒含滤芯吸头
EasySep™人浆细胞样DC分选试剂盒
RoboSep™ 人浆细胞样DC分选试剂盒
Pond AC et al. ( 2013)
Stem cells (Dayton,Ohio) 31 1 10.1002/stem.1266
Fibroblast Growth Factor Receptor Signaling Is Essential for Normal Mammary Gland Development and Stem Cell Function
Fibroblast growth factor (FGF) signaling plays an important role in embryonic stem cells and adult tissue homeostasis,but the function of FGFs in mammary gland stem cells is less well defined. Both FGFR1 and FGFR2 are expressed in basal and luminal mammary epithelial cells (MECs),suggesting that together they might play a role in mammary gland development and stem cell dynamics. Previous studies have demonstrated that the deletion of FGFR2 resulted only in transient developmental defects in branching morphogenesis. Using a conditional deletion strategy,we investigated the consequences of FGFR1 deletion alone and then the simultaneous deletion of both FGFR1 and FGFR2 in the mammary epithelium. FGFR1 deletion using a keratin 14 promoter-driven Cre-recombinase resulted in an early,yet transient delay in development. However,no reduction in functional outgrowth potential was observed following limiting dilution transplantation analysis. In contrast,a significant reduction in outgrowth potential was observed upon the deletion of both FGFR1 and FGFR2 in MECs using adenovirus-Cre. Additionally,using a fluorescent reporter mouse model to monitor Cre-mediated recombination,we observed a competitive disadvantage following transplantation of both FGFR1/R2-null MECs,most prominently in the basal epithelial cells. This correlated with the complete loss of the mammary stem cell repopulating population in the FGFR1/R2-attenuated epithelium. FGFR1/R2-null MECs were partially rescued in chimeric outgrowths containing wild-type MECs,suggesting the potential importance of paracrine mechanisms involved in the maintenance of the basal epithelial stem cells. These studies document the requirement for functional FGFR signaling in mammary stem cells during development.
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EasySep™小鼠TIL（CD45）正选试剂盒
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