Vukovic J et al. (APR 2013)
Journal of Neuroscience 33 15 6603--6613
Immature Doublecortin-Positive Hippocampal Neurons Are Important for Learning But Not for Remembering
It is now widely accepted that hippocampal neurogenesis underpins critical cognitive functions,such as learning and memory. To assess the behavioral importance of adult-born neurons,we developed a novel knock-in mouse model that allowed us to specifically and reversibly ablate hippocampal neurons at an immature stage. In these mice,the diphtheria toxin receptor (DTR) is expressed under control of the doublecortin (DCX) promoter,which allows for specific ablation of immature DCX-expressing neurons after administration of diphtheria toxin while leaving the neural precursor pool intact. Using a spatially challenging behavioral test (a modified version of the active place avoidance test),we present direct evidence that immature DCX-expressing neurons are required for successful acquisition of spatial learning,as well as reversal learning,but are not necessary for the retrieval of stored long-term memories. Importantly,the observed learning deficits were rescued as newly generated immature neurons repopulated the granule cell layer upon termination of the toxin treatment. Repeat (or cyclic) depletion of immature neurons reinstated behavioral deficits if the mice were challenged with a novel task. Together,these findings highlight the potential of stimulating neurogenesis as a means to enhance learning.
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产品类型:
产品号#:
05700
05701
05702
产品名:
NeuroCult™ 基础培养基(小鼠和大鼠)
NeuroCult™ 扩增添加物(小鼠和大鼠)
NeuroCult™扩增试剂盒(小鼠和大鼠)
文献
M. Romera-Hern\'andez et al. (jun 2019)
Current protocols in immunology 125 1 e73
Identification of Group 2 Innate Lymphoid Cells in Mouse Lung, Liver, Small Intestine, Bone Marrow, and Mediastinal and Mesenteric Lymph Nodes.
Innate lymphoid cells (ILCs) are a heterogeneous family of lymphocytes that populate barrier and non-barrier tissues. ILCs regulate immune responses to pathogens and commensals but also sustain metabolic homeostasis,tissue remodeling after injury and establish dialogue with the nervous system. ILCs rapidly become activated in the absence of adaptive antigen receptors by responding to signaling molecules provided by hematopoietic or non-hematopoietic cells. Here we provide protocols designed for processing the lung,liver,small intestine,bone marrow,mediastinal and mesenteric lymph nodes in order to obtain a purified leukocyte fraction of cells,in which ILC2 enrichment is optimized. In addition,we describe in detail the methodologies used to activate ILC2s and the assays necessary for the detection of their effector cytokines. We highlight the differences in ILC2 characterization within distinct tissues that we have recently identified. {\textcopyright} 2019 by John Wiley Sons,Inc.
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产品类型:
产品号#:
19842
产品名:
EasySep™小鼠ILC2富集试剂盒
文献
Ryan MA et al. (OCT 2010)
Nature medicine 16 10 1141--6
Mobilization of hematopoietic stem and progenitor cells (HSPCs) from bone marrow into peripheral blood by the cytokine granulocyte colony-stimulating factor (G-CSF) has become the preferred source of HSPCs for stem cell transplants. However,G-CSF fails to mobilize sufficient numbers of stem cells in up to 10% of donors,precluding autologous transplantation in those donors or substantially delaying transplant recovery time. Consequently,new regimens are needed to increase the number of stem cells in peripheral blood upon mobilization. Using a forward genetic approach in mice,we mapped the gene encoding the epidermal growth factor receptor (Egfr) to a genetic region modifying G-CSF-mediated HSPC mobilization. Amounts of EGFR in HSPCs inversely correlated with the cells' ability to be mobilized by G-CSF,implying a negative role for EGFR signaling in mobilization. In combination with G-CSF treatment,genetic reduction of EGFR activity in HSPCs (in waved-2 mutant mice) or treatment with the EGFR inhibitor erlotinib increased mobilization. Increased mobilization due to suppression of EGFR activity correlated with reduced activity of cell division control protein-42 (Cdc42),and genetic Cdc42 deficiency in vivo also enhanced G-CSF-induced mobilization. Our findings reveal a previously unknown signaling pathway regulating stem cell mobilization and provide a new pharmacological approach for improving HSPC mobilization and thereby transplantation outcomes.
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产品类型:
产品号#:
03234
产品名:
MethoCult™M3234
文献
Morrow M et al. (MAY 2004)
Blood 103 10 3890--6
TEL-AML1 promotes development of specific hematopoietic lineages consistent with preleukemic activity.
The t(12;21)(p13;q22) translocation is the most common chromosomal abnormality yet identified in any pediatric leukemia and gives rise to the TEL-AML1 fusion product. To investigate the effects of TEL-AML1 on hematopoiesis,fetal liver hematopoietic progenitor cells (HPCs) were transduced with retroviral vectors expressing this fusion protein. We show that TEL-AML1 dramatically alters differentiation of HPCs in vitro,preferentially promoting B-lymphocyte development,enhancing self-renewal of B-cell precursors,and leading to the establishment of long-term growth factor-dependent pre-B-cell lines. However,it had no effect on myeloid development in vitro. Further experiments were performed to determine whether TEL-AML1 also demonstrates lineage-specific activity in vivo. TEL-AML1-expressing HPCs displayed a competitive advantage in reconstituting both B-cell and myeloid lineages in vivo but had no effect on reconstitution of the T-cell lineage. Despite promoting these alterations in hematopoiesis,TEL-AML1 did not induce leukemia in transplanted mice. Our study provides a unique insight into the role of TEL-AML1 in leukemia predisposition and a potential model to study the mechanism of leukemogenesis associated with this fusion.
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产品类型:
产品号#:
03534
03231
产品名:
MethoCult™GF M3534
MethoCult™M3231
文献
Liu B et al. (MAR 2014)
PLoS ONE 9 3 e90615
Nanog1 in NTERA-2 and recombinant NanogP8 from somatic cancer cells adopt multiple protein conformations and migrate at multiple M.W species
Human Nanog1 is a 305-amino acid (aa) homeodomain-containing transcription factor critical for the pluripotency of embryonic stem (ES) and embryonal carcinoma (EC) cells. Somatic cancer cells predominantly express a retrogene homolog of Nanog1 called NanogP8,which is ˜99% similar to Nanog at the aa level. Although the predicted M.W of Nanog1/NanogP8 is ∼35 kD,both have been reported to migrate,on Western blotting (WB),at apparent molecular masses of 29-80 kD. Whether all these reported protein bands represent authentic Nanog proteins is unclear. Furthermore,detailed biochemical studies on Nanog1/NanogpP8 have been lacking. By combining WB using 8 anti-Nanog1 antibodies,immunoprecipitation,mass spectrometry,and studies using recombinant proteins,here we provide direct evidence that the Nanog1 protein in NTERA-2 EC cells exists as multiple M.W species from ˜22 kD to 100 kD with a major 42 kD band detectable on WB. We then demonstrate that recombinant NanogP8 (rNanogP8) proteins made in bacteria using cDNAs from multiple cancer cells also migrate,on denaturing SDS-PAGE,at ˜28 kD to 180 kD. Interestingly,different anti-Nanog1 antibodies exhibit differential reactivity towards rNanogP8 proteins,which can spontaneously form high M.W protein species. Finally,we show that most long-term cultured cancer cell lines seem to express very low levels of or different endogenous NanogP8 protein that cannot be readily detected by immunoprecipitation. Altogether,the current study reveals unique biochemical properties of Nanog1 in EC cells and NanogP8 in somatic cancer cells.
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产品类型:
产品号#:
85850
85857
产品名:
mTeSR™1
mTeSR™1
文献
Fenouille N et al. (DEC 2010)
Cancer research 70 23 9659--70
Persistent activation of the Fyn/ERK kinase signaling axis mediates imatinib resistance in chronic myelogenous leukemia cells through upregulation of intracellular SPARC.
SPARC is an extracellular matrix protein that exerts pleiotropic effects on extracellular matrix organization,growth factor availability,cell adhesion,differentiation,and immunity in cancer. Chronic myelogenous leukemia (CML) cells resistant to the BCR-ABL inhibitor imatinib (IM-R cells) were found to overexpress SPARC mRNA. In this study,we show that imatinib triggers SPARC accumulation in a variety of tyrosine kinase inhibitor (TKI)-resistant CML cell lines. SPARC silencing in IM-R cells restored imatinib sensitivity,whereas enforced SPARC expression in imatinib-sensitive cells promoted viability as well as protection against imatinib-mediated apoptosis. Notably,we found that the protective effect of SPARC required intracellular retention inside cells. Accordingly,SPARC was not secreted into the culture medium of IM-R cells. Increased SPARC expression was intimately linked to persistent activation of the Fyn/ERK kinase signaling axis. Pharmacologic inhibition of this pathway or siRNA-mediated knockdown of Fyn kinase resensitized IM-R cells to imatinib. In support of our findings,increased levels of SPARC mRNA were documented in blood cells from CML patients after 1 year of imatinib therapy compared with initial diagnosis. Taken together,our results highlight an important role for the Fyn/ERK signaling pathway in imatinib-resistant cells that is driven by accumulation of intracellular SPARC.
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产品类型:
产品号#:
04100
产品名:
MethoCult™H4100
文献
Wang P et al. ( 2017)
Molecular autism 8 11
CRISPR/Cas9-mediated heterozygous knockout of the autism gene CHD8 and characterization of its transcriptional networks in cerebral organoids derived from iPS cells.
BACKGROUND CHD8 (chromodomain helicase DNA-binding protein 8),which codes for a member of the CHD family of ATP-dependent chromatin-remodeling factors,is one of the most commonly mutated genes in autism spectrum disorders (ASD) identified in exome-sequencing studies. Loss of function mutations in the gene have also been found in schizophrenia (SZ) and intellectual disabilities and influence cancer cell proliferation. We previously reported an RNA-seq analysis carried out on neural progenitor cells (NPCs) and monolayer neurons derived from induced pluripotent stem (iPS) cells that were heterozygous for CHD8 knockout (KO) alleles generated using CRISPR-Cas9 gene editing. A significant number of ASD and SZ candidate genes were among those that were differentially expressed in a comparison of heterozygous KO lines (CHD8(+/-)) vs isogenic controls (CHD8(+/-)),including the SZ and bipolar disorder (BD) candidate gene TCF4,which was markedly upregulated in CHD8(+/-) neuronal cells. METHODS In the current study,RNA-seq was carried out on CHD8(+/-) and isogenic control (CHD8(+/+)) cerebral organoids,which are 3-dimensional structures derived from iPS cells that model the developing human telencephalon. RESULTS TCF4 expression was,again,significantly upregulated. Pathway analysis carried out on differentially expressed genes (DEGs) revealed an enrichment of genes involved in neurogenesis,neuronal differentiation,forebrain development,Wnt/β-catenin signaling,and axonal guidance,similar to our previous study on NPCs and monolayer neurons. There was also significant overlap in our CHD8(+/-) DEGs with those found in a transcriptome analysis carried out by another group using cerebral organoids derived from a family with idiopathic ASD. Remarkably,the top DEG in our respective studies was the non-coding RNA DLX6-AS1,which was markedly upregulated in both studies; DLX6-AS1 regulates the expression of members of the DLX (distal-less homeobox) gene family. DLX1 was also upregulated in both studies. DLX genes code for transcription factors that play a key role in GABAergic interneuron differentiation. Significant overlap was also found in a transcriptome study carried out by another group using iPS cell-derived neurons from patients with BD,a condition characterized by dysregulated WNT/β-catenin signaling in a subgroup of affected individuals. CONCLUSIONS Overall,the findings show that distinct ASD,SZ,and BD candidate genes converge on common molecular targets-an important consideration for developing novel therapeutics in genetically heterogeneous complex traits.
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产品类型:
产品号#:
85850
85857
产品名:
mTeSR™1
mTeSR™1
文献
Hoggatt J et al. (MAY 2009)
Blood 113 22 5444--55
Prostaglandin E2 enhances hematopoietic stem cell homing, survival, and proliferation.
Adult hematopoietic stem cells (HSCs) are routinely used to reconstitute hematopoiesis after myeloablation; however,transplantation efficacy and multilineage reconstitution can be limited by inadequate HSC number,or poor homing,engraftment,or self-renewal. Here we report that mouse and human HSCs express prostaglandin E2 (PGE2) receptors,and that short-term ex vivo exposure of HSCs to PGE2 enhances their homing,survival,and proliferation,resulting in increased long-term repopulating cell (LTRC) and competitive repopulating unit (CRU) frequency. HSCs pulsed with PGE2 are more competitive,as determined by head-to-head comparison in a competitive transplantation model. Enhanced HSC frequency and competitive advantage is stable and maintained upon serial transplantation,with full multilineage reconstitution. PGE2 increases HSC CXCR4 mRNA and surface expression,enhances their migration to SDF-1 in vitro and homing to bone marrow in vivo,and stimulates HSC entry into and progression through cell cycle. In addition,PGE2 enhances HSC survival,associated with an increase in Survivin mRNA and protein expression and reduction in intracellular active caspase-3. Our results define novel mechanisms of action whereby PGE2 enhances HSC function and supports a strategy to use PGE2 to facilitate hematopoietic transplantation.
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