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
01701
01702
产品名:
ALDEFLUOR™ 试剂盒
ALDEFLUOR™ DEAB试剂
ALDEFLUOR™测定缓冲液
Bruserud &O et al. (MAY 2003)
Leukemia research 27 5 455--64
In vitro culture of human acute lymphoblastic leukemia (ALL) cells in serum-free media; a comparison of native ALL blasts, ALL cell lines and virus-transformed B cell lines.
The aim of this study was to standardize in vitro culture conditions for human acute lymphoblastic leukemia (ALL) cells. The cells were cultured in medium containing 10% fetal calf serum (FCS) and in the four serum-free media X-vivo 10,X-vivo 15,X-vivo 20 and Stem Span. Native ALL blasts could proliferate in all four serum-free media,but the strongest responses were usually observed with Stem Span. Native leukemia blasts were also cultured in the presence of various single cytokines or cytokine combinations. The highest proliferation was usually observed in the presence of Flt3-Ligand (Flt3-L) when single cytokines were examined,and these responses could be further increased especially by combining Flt3-L with interleukin 3 (IL3),IL7 or stem cell factor (SCF). Proliferation could also be increased when ALL blasts were cultured in the presence of two commercially available fibroblast cell lines (Hs27 and HFL1). Based on these results we suggest that in vitro culture conditions for native human ALL blasts can be standardized by using serum-free culture media supplemented with exogenous Flt3-L+IL3+SCF,and the use of accessory cells can also be standardized by using well-characterized fibroblast cell lines. Detectable ALL blast proliferation can then be observed for most patients. Our experimental model can thereby be used for in vitro evaluation of possible antileukemic treatment strategies,and it will then allow comparison of experimental results between different studies.
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Finstad SL et al. (JUL 2007)
Journal of virology 81 13 7274--9
Diminished potential for B-lymphoid differentiation after murine leukemia virus infection in vivo and in EML hematopoietic progenitor cells.
Infection with a recombinant murine-feline gammaretrovirus,MoFe2,or with the parent virus,Moloney murine leukemia virus,caused significant reduction in B-lymphoid differentiation of bone marrow at 2 to 8 weeks postinfection. The suppression was selective,in that myeloid potential was significantly increased by infection. Analysis of cell surface markers and immunoglobulin H gene rearrangements in an in vitro model demonstrated normal B-lymphoid differentiation after infection but significantly reduced viability of differentiating cells. This reduction in viability may confer a selective advantage on undifferentiated lymphoid progenitors in the bone marrow of gammaretrovirus-infected animals and thereby contribute to the establishment of a premalignant state.
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Hawley RG et al. (JAN 2006)
Methods in enzymology 419 149--79
Hematopoietic stem cells.
Hematopoietic stem cells (HSCs) have the capacity to self-renew and the potential to differentiate into all of the mature blood cell types. The ability to prospectively identify and isolate HSCs has been the subject of extensive investigation since the first transplantation studies implying their existence almost 50 years ago. Despite significant advances in enrichment protocols,the continuous in vitro propagation of human HSCs has not yet been achieved. This chapter describes current procedures used to phenotypically and functionally characterize candidate human HSCs and initial efforts to derive permanent human HSC lines.
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Bruserud O et al. (DEC 2000)
Journal of hematotherapy & stem cell research 9 6 923--32
In vitro culture of human acute myelogenous leukemia (AML) cells in serum-free media: studies of native AML blasts and AML cell lines.
The functional characteristics were compared for acute myelogenous leukemia (AML) cells (native blasts and AML cell lines) cultured in three serum-free media (X-vivo 10,X-vivo 15,[Bio-Whitacker,Walkersville,MD] and StemSpan [Stem Cell Technologies,Vancouver,BC,Canada]) and in medium containing 10% inactivated fetal calf serum (FCS). For native AML blasts the following functions were compared: (1) autonomous and cytokine-dependent proliferation; (2) frequency of clonogenic cell; and (3) constitutive cytokine secretion. AML blast proliferation differed between patients independent of the culture medium used,and clonogenic cells were maintained after in vitro culture in all media. In contrast,constitutive cytokine secretion was higher for cells cultured in StemSpan and FCS-containing medium than for cells cultured in the X-vivo media. Native AML blasts incubated in StemSpan also showed a low frequency of apoptotic cells. The three serum-free media could also be used for long-term expansion of well-characterized AML cell lines,but the optimal medium for cell expansion and cytokine secretion differed between cell lines. We conclude that standardized serum-free culture conditions can be used for in vitro studies of native AML blasts and AML cell lines.
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Smad4 binds Hoxa9 in the cytoplasm and protects primitive hematopoietic cells against nuclear activation by Hoxa9 and leukemia transformation.
We studied leukemic stem cells (LSCs) in a Smad4(-/-) mouse model of acute myelogenous leukemia (AML) induced either by the HOXA9 gene or by the fusion oncogene NUP98-HOXA9. Although Hoxa9-Smad4 complexes accumulate in the cytoplasm of normal hematopoietic stem cells and progenitor cells (HSPCs) transduced with these oncogenes,there is no cytoplasmic stabilization of HOXA9 in Smad4(-/-) HSPCs,and as a consequence increased levels of Hoxa9 is observed in the nucleus leading to increased immortalization in vitro. Loss of Smad4 accelerates the development of leukemia in vivo because of an increase in transformation of HSPCs. Therefore,the cytoplasmic binding of Hoxa9 by Smad4 is a mechanism to protect Hoxa9-induced transformation of normal HSPCs. Because Smad4 is a potent tumor suppressor involved in growth control,we developed a strategy to modify the subcellular distribution of Smad4. We successfully disrupted the interaction between Hoxa9 and Smad4 to activate the TGF-β pathway and apoptosis,leading to a loss of LSCs. Together,these findings reveal a major role for Smad4 in the negative regulation of leukemia initiation and maintenance induced by HOXA9/NUP98-HOXA9 and provide strong evidence that antagonizing Smad4 stabilization by these oncoproteins might be a promising novel therapeutic approach in leukemia.
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