Aldehyde dehydrogenase 1a1 is dispensable for stem cell function in the mouse hematopoietic and nervous systems.
High levels of aldehyde dehydrogenase (ALDH) activity have been proposed to be a common feature of stem cells. Adult hematopoietic,neural,and cancer stem cells have all been reported to have high ALDH activity,detected using Aldefluor,a fluorogenic substrate for ALDH. This activity has been attributed to Aldh1a1,an enzyme that is expressed at high levels in stem cells and that has been suggested to regulate stem cell function. Nonetheless,Aldh1a1 function in stem cells has never been tested genetically. We observed that Aldh1a1 was preferentially expressed in mouse hematopoietic stem cells (HSCs) and expression increased with age. Hematopoietic cells from Aldh1a1-deficient mice exhibited increased sensitivity to cyclophosphamide in a non-cell-autonomous manner,consistent with its role in cyclophosphamide metabolism in the liver. However,Aldh1a1 deficiency did not affect hematopoiesis,HSC function,or the capacity to reconstitute irradiated recipients in young or old adult mice. Aldh1a1 deficiency also did not affect Aldefluor staining of hematopoietic cells. Finally,Aldh1a1 deficiency did not affect the function of stem cells from the adult central or peripheral nervous systems. Aldh1a1 is not a critical regulator of adult stem cell function or Aldefluor staining in mice.
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Ibarra I et al. (DEC 2007)
Genes & development 21 24 3238--43
A role for microRNAs in maintenance of mouse mammary epithelial progenitor cells.
microRNA (miRNA) expression profiles are often characteristic of specific cell types. The mouse mammary epithelial cell line,Comma-Dbeta,contains a population of self-renewing progenitor cells that can reconstitute the mammary gland. We purified this population and determined its miRNA signature. Several microRNAs,including miR-205 and miR-22,are highly expressed in mammary progenitor cells,while others,including let-7 and miR-93,are depleted. Let-7 sensors can be used to prospectively enrich self-renewing populations,and enforced let-7 expression induces loss of self-renewing cells from mixed cultures.
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产品类型：
产品号#：
01700
01705
01702
产品名：
ALDEFLUOR™工具
ALDEFLUOR™ DEAB试剂
ALDEFLUOR™测定缓冲液
文献
Haddad EA et al. (SEP 2009)
Journal of immunology (Baltimore,Md. : 1950) 183 6 3608--15
An accessory role for B cells in the IL-12-induced activation of resting mouse NK cells.
IL-12 is a potent proinflammatory cytokine. The effects of IL-12 are thought to be mediated by IFN-gamma production by NK,NKT,and T cells. In this study,we show that although IL-12 stimulates NK and NK1.1(+) T cells in bulk mouse splenocytes,it does not significantly stimulate purified NK cells,indicating that other cells are required. IL-12 stimulates T cell-deficient spleen cells and those depleted of macrophages. Unexpectedly,the depletion of dendritic cells also has little effect on the stimulation of spleen cells with IL-12. In contrast,B cell depletion almost completely inhibits IL-12-induced IFN-gamma production and B cell-deficient spleen cells are poorly stimulated with IL-12. Furthermore,purified NK cells are stimulated with IL-12 in the presence of purified B cells. Thus,B cells are necessary and also sufficient for the stimulation of purified NK cells with IL-12. Whereas spleen cells from IL-18-deficient mice are not stimulated with IL-12,NK cells purified from IL-18-deficient mice are stimulated with IL-12 in the presence of wild-type (WT) B cells,and WT NK cells are not stimulated with IL-12 in the presence of IL-18-deficient B cells. Cell contact between B and NK cells is also required for IL-12-induced IFN-gamma production. Finally,B cell-deficient mice injected with IL-12 produce significantly less IFN-gamma and IL-18 in the sera than WT mice do. Thus,stimulation of NK cells with IL-12 requires B cell cooperation in vitro as well as in vivo.
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文献
Aguila JR et al. (JUL 2011)
Blood 118 3 576--85
SALL4 is a robust stimulator for the expansion of hematopoietic stem cells.
HSCs are rare cells that have the unique ability to self-renew and differentiate into cells of all hematopoietic lineages. The lack of donors and current inability to rapidly and efficiently expand HSCs are roadblocks in the development of successful cell therapies. Thus,the challenge of ex vivo human HSC expansion remains a fertile and critically important area of investigation. Here,we show that either SALL4A- or SALL4B-transduced human HSCs obtained from the mobilized peripheral blood are capable of rapid and efficient expansion ex vivo by textgreater10 000-fold for both CD34(+)/CD38(-) and CD34(+)/CD38(+) cells in the presence of appropriate cytokines. We found that these cells retained hematopoietic precursor cell immunophenotypes and morphology as well as normal in vitro or vivo potential for differentiation. The SALL4-mediated expansion was associated with enhanced stem cell engraftment and long-term repopulation capacity in vivo. Also,we demonstrated that constitutive expression of SALL4 inhibited granulocytic differentiation and permitted expansion of undifferentiated cells in 32D myeloid progenitors. Furthermore,a TAT-SALL4B fusion rapidly expanded CD34(+) cells,and it is thus feasible to translate this study into the clinical setting. Our findings provide a new avenue for investigating mechanisms of stem cell self-renewal and achieving clinically significant expansion of human HSCs.
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Essential role for Ptpn11 in survival of hematopoietic stem and progenitor cells.
Src homology 2 domain-containing phosphatase 2 (Shp2),encoded by Ptpn11,is a member of the nonreceptor protein-tyrosine phosphatase family,and functions in cell survival,proliferation,migration,and differentiation in many tissues. Here we report that loss of Ptpn11 in murine hematopoietic cells leads to bone marrow aplasia and lethality. Mutant mice show rapid loss of hematopoietic stem cells (HSCs) and immature progenitors of all hematopoietic lineages in a gene dosage-dependent and cell-autonomous manner. Ptpn11-deficient HSCs and progenitors undergo apoptosis concomitant with increased Noxa expression. Mutant HSCs/progenitors also show defective Erk and Akt activation in response to stem cell factor and diminished thrombopoietin-evoked Erk activation. Activated Kras alleviates the Ptpn11 requirement for colony formation by progenitors and cytokine/growth factor responsiveness of HSCs,indicating that Ras is functionally downstream of Shp2 in these cells. Thus,Shp2 plays a critical role in controlling the survival and maintenance of HSCs and immature progenitors in vivo.
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产品类型：
产品号#：
03231
09600
09650
产品名：
MethoCult™M3231
StemSpan™ SFEM
StemSpan™ SFEM
文献
Eminli S et al. (SEP 2009)
Nature genetics 41 9 968--76
Differentiation stage determines potential of hematopoietic cells for reprogramming into induced pluripotent stem cells.
The reprogramming of somatic cells into induced pluripotent stem (iPS) cells upon overexpression of the transcription factors Oct4,Sox2,Klf4 and cMyc is inefficient. It has been assumed that the somatic differentiation state provides a barrier for efficient reprogramming; however,direct evidence for this notion is lacking. Here,we tested the potential of mouse hematopoietic cells at different stages of differentiation to be reprogrammed into iPS cells. We show that hematopoietic stem and progenitor cells give rise to iPS cells up to 300 times more efficiently than terminally differentiated B and T cells do,yielding reprogramming efficiencies of up to 28%. Our data provide evidence that the differentiation stage of the starting cell has a critical influence on the efficiency of reprogramming into iPS cells. Moreover,we identify hematopoietic progenitors as an attractive cell type for applications of iPS cell technology in research and therapy.
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EasySep™小鼠TIL（CD45）正选试剂盒
50:59
线上研讨会Gene Targeting in Hematopoietic Stem Cells for Basic and Translational Research发布日期: 11/28/18
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技术窍门Genome Editing of Human CD34+ Hematopoietic Stem and Progenitor Cells Using the ArciTect™ CRISPR-Cas9 System and StemSpan™ Media
科学海报Optimized Media and Workflow for the Expansion of Human Pluripotent Stem Cells as Aggregates in Suspension Cultures
53:35
Optimization and Standardization of the Colony-Forming Unit Assay for Hematopoietic Progenitor Cells
BrochureCryopreservation Media for Stem Cell Research
Improved Ex Vivo Expansion of Hematopoietic Progenitor Cells from Cord Blood in a Novel Serum and Animal Component Free Medium
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