BUBR1 deficiency results in abnormal megakaryopoiesis.
The physiologic function of BUBR1,a key component of the spindle checkpoint,was examined by generating BUBR1-mutant mice. BUBR1(-/-) embryos failed to survive beyond day 8.5 in utero as a result of extensive apoptosis. Whereas BUBR1(+/-) blastocysts grew relatively normally in vitro,BUBR1(-/-) blastocysts exhibited impaired proliferation and atrophied. Adult BUBR1(+/-) mice manifested splenomegaly and abnormal megakaryopoiesis. BUBR1 haploinsufficiency resulted in an increase in the number of splenic megakaryocytes,which was correlated with an increase in megakaryocytic,but a decrease in erythroid,progenitors in bone marrow cells. RNA interference-mediated down-regulation of BUBR1 also caused an increase in polyploidy formation in murine embryonic fibroblast cells and enhanced megakaryopoiesis in bone marrow progenitor cells. However,enhanced megakaryopoiesis in BUBR1(+/-) mice was not correlated with a significant increase in platelets in peripheral blood,which was at least partly due to a defect in the formation of proplatelet-producing megakaryocytes. Together,these results indicate that BUBR1 is essential for early embryonic development and normal hematopoiesis.
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产品类型:
产品号#:
09600
09650
04960
04902
04900
04961
04901
04963
04962
04970
04971
产品名:
StemSpan™ SFEM
StemSpan™ SFEM
MegaCult™-C胶原和无细胞因子培养基
胶原蛋白溶液
MegaCult™-C无细胞因子培养基
MegaCult™-C胶原和含细胞因子培养基
MegaCult™-C含细胞因子培养基
双室载玻片套件
MegaCult™-C CFU-Mk染色试剂盒
MegaCult™-C无细胞因子全套试剂盒
MegaCult™-C含细胞因子全套试剂盒
Migliaccio AR et al. (FEB 2003)
The Journal of experimental medicine 197 3 281--96
GATA-1 as a regulator of mast cell differentiation revealed by the phenotype of the GATA-1low mouse mutant.
Here it is shown that the phenotype of adult mice lacking the first enhancer (DNA hypersensitive site I) and the distal promoter of the GATA-1 gene (neo Delta HS or GATA-1(low) mutants) reveals defects in mast cell development. These include the presence of morphologically abnormal alcian blue(+) mast cells and apoptotic metachromatic(-) mast cell precursors in connective tissues and peritoneal lavage and numerous (60-70% of all the progenitors) unique" trilineage cells committed to erythroid�
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产品类型:
产品号#:
04960
04902
04900
04961
04901
04963
04962
04970
04971
产品名:
MegaCult™-C胶原和无细胞因子培养基
胶原蛋白溶液
MegaCult™-C无细胞因子培养基
MegaCult™-C胶原和含细胞因子培养基
MegaCult™-C含细胞因子培养基
双室载玻片套件
MegaCult™-C CFU-Mk染色试剂盒
MegaCult™-C无细胞因子全套试剂盒
MegaCult™-C含细胞因子全套试剂盒
Halene S et al. (SEP 2010)
Blood 116 11 1942--50
Serum response factor is an essential transcription factor in megakaryocytic maturation.
Serum response factor (Srf) is a MADS-box transcription factor that is critical for muscle differentiation. Its function in hematopoiesis has not yet been revealed. Mkl1,a cofactor of Srf,is part of the t(1;22) translocation in acute megakaryoblastic leukemia,and plays a critical role in megakaryopoiesis. To test the role of Srf in megakaryocyte development,we crossed Pf4-Cre mice,which express Cre recombinase in cells committed to the megakaryocytic lineage,to Srf(F/F) mice in which functional Srf is no longer expressed after Cre-mediated excision. Pf4-Cre/Srf(F/F) knockout (KO) mice are born with normal Mendelian frequency,but have significant macrothrombocytopenia with approximately 50% reduction in platelet count. In contrast,the BM has increased number and percentage of CD41(+) megakaryocytes (WT: 0.41% ± 0.06%; KO: 1.92% ± 0.12%) with significantly reduced ploidy. KO mice show significantly increased megakaryocyte progenitors in the BM by FACS analysis and CFU-Mk. Megakaryocytes lacking Srf have abnormal stress fiber and demarcation membrane formation,and platelets lacking Srf have abnormal actin distribution. In vitro and in vivo assays reveal platelet function defects in KO mice. Critical actin cytoskeletal genes are down-regulated in KO megakaryocytes. Thus,Srf is required for normal megakaryocyte maturation and platelet production partly because of regulation of cytoskeletal genes.
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产品类型:
产品号#:
09500
09600
09650
04971
04902
04901
04963
04962
产品名:
BIT 9500血清替代物
StemSpan™ SFEM
StemSpan™ SFEM
MegaCult™-C含细胞因子全套试剂盒
胶原蛋白溶液
MegaCult™-C含细胞因子培养基
双室载玻片套件
MegaCult™-C CFU-Mk染色试剂盒
Cheng E-C et al. (MAR 2009)
Blood 113 12 2826--34
Role for MKL1 in megakaryocytic maturation.
Megakaryoblastic leukemia 1 (MKL1),identified as part of the t(1;22) translocation specific to acute megakaryoblastic leukemia,is highly expressed in differentiated muscle cells and promotes muscle differentiation by activating serum response factor (SRF). Here we show that Mkl1 expression is up-regulated during murine megakaryocytic differentiation and that enforced overexpression of MKL1 enhances megakaryocytic differentiation. When the human erythroleukemia (HEL) cell line is induced to differentiate with 12-O-tetradecanoylphorbol 13-acetate,overexpression of MKL1 results in an increased number of megakaryocytes with a concurrent increase in ploidy. MKL1 overexpression also promotes megakaryocytic differentiation of primary human CD34(+) cells cultured in the presence of thrombopoietin. The effect of MKL1 is abrogated when SRF is knocked down,suggesting that MKL1 acts through SRF. Consistent with these findings in human cells,knockout of Mkl1 in mice leads to reduced platelet counts in peripheral blood,and reduced ploidy in bone marrow megakaryocytes. In conclusion,MKL1 promotes physiologic maturation of human and murine megakaryocytes.
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产品类型:
产品号#:
09500
09600
09650
04960
04902
04900
04963
04962
04970
04971
04901
产品名:
BIT 9500血清替代物
StemSpan™ SFEM
StemSpan™ SFEM
MegaCult™-C胶原和无细胞因子培养基
胶原蛋白溶液
MegaCult™-C无细胞因子培养基
双室载玻片套件
MegaCult™-C CFU-Mk染色试剂盒
MegaCult™-C无细胞因子全套试剂盒
MegaCult™-C含细胞因子全套试剂盒
MegaCult™-C含细胞因子培养基
Dobo I et al. (DEC 1999)
Journal of hematotherapy & stem cell research 8 6 601--7
Endogenous erythroid and megakaryocytic colony formation in serum-free, cytokine-free collagen gels.
We studied the suitability of collagen-based semisolid medium for assay of endogenous erythroid colony formation performed in myeloproliferative disorders. Bone marrow (BM) mononuclear cells (MNC) from 103 patients suspected of having polycythemia vera (PV,76 patients) or essential thrombocythemia (ET,27 patients) were grown in collagen-based,serum-free,cytokine-free semisolid medium. Colony analysis at day 8 or 10 showed that this collagen assay is specific,as endogenous growth of erythroid colonies was never observed in cultures of 16 healthy donors and 6 chronic myelogenous leukemia (CML) patients. Endogenous erythroid colony formation was observed in 53.3% of patients suspected of PV,with only 15.4% of positive cultures for patients with 1 minor PV criterion and 72% (p = 0.009) of positive cultures for patients with textgreater or =2 minor or 1 major PV criterion. Similarly,endogenous growth of erythroid colonies was found in 44.4% of patients suspected of ET,with 31.6% of positive cultures for patients with 1 ET criterion versus 75% for patients with textgreater or =2 ET criteria. In addition,we found that in collagen gels,tests of erythropoietin (EPO) hypersensitivity in the presence of 0.01 or 0.05 U/ml of EPO and tests of endogenous colony-forming units-megakaryocyte (CFU-MK) formation cannot be used to detect PV or ET,as these tests were positive for,respectively,21.4% and 50% of healthy donors and 83% and 50% of CML patients. A retrospective analysis suggests that collagen assays are more sensitive than methylcellulose assays to assess endogenous growth of erythroid colonies. In summary,serum-free collagen-based colony assays are simple and reliable assays of endogenous growth of erythroid colonies in myeloproliferative diseases. They also appear to be more sensitive than methylcellulose-based assays.
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产品类型:
产品号#:
04961
04965
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04915
04807
04809
04906
04913
04803
04804
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04974
04902
04960
04900
04901
04963
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04971
产品名:
MegaCult™-C胶原和含细胞因子培养基
MegaCult™-C CFU-Mk染色试剂盒
MegaCult-C 10% BSA, 6mL
MegaCult-C Human Serum, 6mL
Alkaline Phosphatase Substrate Tabs, pk
Biotin/Conjugate Goat Anti-Mu lgG, 125uL
MegaCult-C Evans Blue Stain, 5mL
Primary Ab, Anti-HuAnti-GPIIb/IIIa 360uL
MegaCult-C Control Antibody, 100 µL
Avidin-Alk Phosphatase Conjugate, 200 uL
MegaCult™-C含脂质培养基
MegaCult™-C胶原和含脂质培养基
胶原蛋白溶液
MegaCult™-C胶原和无细胞因子培养基
MegaCult™-C无细胞因子培养基
MegaCult™-C含细胞因子培养基
双室载玻片套件
MegaCult™-C无细胞因子全套试剂盒
MegaCult™-C含细胞因子全套试剂盒
Ito CY et al. (JAN 2003)
Blood 101 2 517--23
Hematopoietic stem cell and progenitor defects in Sca-1/Ly-6A-null mice.
Despite its wide use as a marker for hematopoietic stem cells (HSCs),the function of stem cell antigen-1 (Sca-1) (also known as lymphocyte activation protein-6A [Ly-6A]) in hematopoiesis remains poorly defined. We have previously established that Sca-1(-/-) T cells develop normally,although they are hyperresponsive to antigen. Here,we report detailed analysis of hematopoiesis in Sca-1-deficient animals. The differentiation potential of Sca-1-null bone marrow was determined from examination of the most mature precursors (culture colony-forming units [CFU-Cs]) to less committed progenitors (spleen CFUs [CFU-Ss]) to long-term repopulating HSCs. Sca-1-null mice are mildly thrombocytopenic with a concomitant decrease in megakaryocytes and their precursors. Bone marrow cells derived from Sca-1(-/-) mice also have decreased multipotential granulocyte,erythroid,macrophage,and megakaryocyte CFU (GEMM-CFU) and CFU-S progenitor activity. Competitive repopulation assays demonstrated that Sca-1(-/-) HSCs are at a competitive disadvantage compared with wild-type HSCs. To further analyze the potential of Sca-1(-/-) HSCs,serial transplantations were performed. While secondary repopulations using wild-type bone marrow completely repopulated Sca-1(-/-) mice,Sca-1(-/-) bone marrow failed to rescue one third of lethally irradiated wild-type mice receiving secondary bone marrow transplants from irradiation-induced anemia and contributed poorly to the surviving transplant recipients. These data strongly suggest that Sca-1 is required for regulating HSC self-renewal and the development of committed progenitor cells,megakaryocytes,and platelets. Thus,our studies conclusively demonstrate that Sca-1,in addition to being a marker of HSCs,regulates the developmental program of HSCs and specific progenitor populations.
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产品类型:
产品号#:
03434
03444
04960
04902
04900
04961
04901
04963
04962
04970
04971
产品名:
MethoCult™ GF M3434
MethoCult™ GF M3434
MegaCult™-C胶原和无细胞因子培养基
胶原蛋白溶液
MegaCult™-C无细胞因子培养基
MegaCult™-C胶原和含细胞因子培养基
MegaCult™-C含细胞因子培养基
双室载玻片套件
MegaCult™-C CFU-Mk染色试剂盒
MegaCult™-C无细胞因子全套试剂盒
MegaCult™-C含细胞因子全套试剂盒
Kimura Y et al. (APR 2004)
Proceedings of the National Academy of Sciences of the United States of America 101 16 6015--20
Targeted mutations of the juxtamembrane tyrosines in the Kit receptor tyrosine kinase selectively affect multiple cell lineages.
Loss-of-function mutations in the murine dominant white spotting/c-kit locus affect a diverse array of biological processes and cell lineages and cause a range of phenotypes,including severe anemia,defective pigmentation,sterility,mast cell deficits,a lack of interstitial cells of Cajal,spatial learning memory deficits,and defects in peripheral nerve regeneration. Here we show that tyrosine residues 567 and 569 in the juxtamembrane (Jx) domain of the murine Kit receptor tyrosine kinase are crucial for the function of Kit in melanogenesis and mast cell development,but are dispensable for the normal development of erythroid,interstitial cells of Cajal and germ cells. Furthermore,adult mice lacking both tyrosines exhibit splenomegaly,dysregulation of B-cell and megakaryocyte development,and enlarged stomachs. Analysis of signal transduction events induced by the mutant receptors after ligand stimulation indicates that Jx tyrosine mutations diminish receptor autophosphorylation and selectively attenuate activation of extracellular signal-regulated kinase/mitogen-activated protein kinases. Together,these observations demonstrate that the Jx domain of Kit plays a cell-type specific regulatory role in vivo and illustrate how engineered mutations in Kit can be used to understand the complex biological and molecular events that result from activating a receptor tyrosine kinase.
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产品类型:
产品号#:
03434
03444
04960
04902
04900
04961
04901
04963
04962
04970
04971
产品名:
MethoCult™ GF M3434
MethoCult™ GF M3434
MegaCult™-C胶原和无细胞因子培养基
胶原蛋白溶液
MegaCult™-C无细胞因子培养基
MegaCult™-C胶原和含细胞因子培养基
MegaCult™-C含细胞因子培养基
双室载玻片套件
MegaCult™-C CFU-Mk染色试剂盒
MegaCult™-C无细胞因子全套试剂盒
MegaCult™-C含细胞因子全套试剂盒
Campard D et al. (MAY 2006)
Stem cells (Dayton,Ohio) 24 5 1302--14
Multilevel regulation of IL-6R by IL-6-sIL-6R fusion protein according to the primitiveness of peripheral blood-derived CD133+ cells.
Interleukin-6 (IL-6) and its soluble receptor (sIL-6R) are major factors for maintenance and expansion of hematopoietic stem cells (HSCs). Sensitivity of HSCs to IL-6 has been previously studied,in part by measuring the expression of IL-6R on the membrane (mIL-6R). Several studies have described the regulation of cell surface expression of IL-6R by several cytokines,but the role of glycoprotein 130 activation has not yet been investigated. In this study,CD133(+) cells were purified from adult peripheral blood and were precultured in the absence or presence of 5-fluorouracil (5-FU) for selection of quiescent HSCs. Cells were cultured with continuous or pulsed stimulations of an IL-6-sIL-6R fusion protein (hyperinterleukin-6 [HIL-6]) to 1) detect mIL-6R by flow cytometry,2) assess mIL-6R and sIL-6R RNAs by reverse transcription-polymerase chain reaction,3) measure sIL-6R in supernatants by enzyme-linked immunosorbent assay,4) analyze cell-cycle status,and 5) perform long-term culture-initiating cell assays. The level of mIL-6R(-) cells was preserved by 5-FU incubation. HIL-6 increased steady-state mIL-6R RNA and expression rate on HSCs,independently of treatment with 5-FU. Enhanced production of sIL-6R was observed with short pulses of HIL-6 on CD133(+) 5-FU-pretreated cells. This overproduction of sIL-6R was abrogated by tumor necrosis factor-alpha protease inhibitor-1,an inhibitor of a disintegrin and metalloprotease proteases,suggesting the shedding of mIL-6R. This phenomenon was mediated through the phosphatidylinositol-3'-kinase pathway and was involved in the maintenance of primitive HSCs. In conclusion,expression and production of IL-6R are tightly regulated and stage specific. We assume that sIL-6R produced by shedding should be involved in autocrine and paracrine loops in the HSC microenvironment.
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产品类型:
产品号#:
09600
09650
04960
04902
04900
04961
04901
04963
04962
04970
04971
产品名:
StemSpan™ SFEM
StemSpan™ SFEM
MegaCult™-C胶原和无细胞因子培养基
胶原蛋白溶液
MegaCult™-C无细胞因子培养基
MegaCult™-C胶原和含细胞因子培养基
MegaCult™-C含细胞因子培养基
双室载玻片套件
MegaCult™-C CFU-Mk染色试剂盒
MegaCult™-C无细胞因子全套试剂盒
MegaCult™-C含细胞因子全套试剂盒
Gu T-l et al. (JUL 2007)
Blood 110 1 323--33
A novel fusion of RBM6 to CSF1R in acute megakaryoblastic leukemia.
Activated tyrosine kinases have been frequently implicated in the pathogenesis of cancer,including acute myeloid leukemia (AML),and are validated targets for therapeutic intervention with small-molecule kinase inhibitors. To identify novel activated tyrosine kinases in AML,we used a discovery platform consisting of immunoaffinity profiling coupled to mass spectrometry that identifies large numbers of tyrosine-phosphorylated proteins,including active kinases. This method revealed the presence of an activated colony-stimulating factor 1 receptor (CSF1R) kinase in the acute megakaryoblastic leukemia (AMKL) cell line MKPL-1. Further studies using siRNA and a small-molecule inhibitor showed that CSF1R is essential for the growth and survival of MKPL-1 cells. DNA sequence analysis of cDNA generated by 5'RACE from CSF1R coding sequences identified a novel fusion of the RNA binding motif 6 (RBM6) gene to CSF1R gene generated presumably by a t(3;5)(p21;q33) translocation. Expression of the RBM6-CSF1R fusion protein conferred interleukin-3 (IL-3)-independent growth in BaF3 cells,and induces a myeloid proliferative disease (MPD) with features of megakaryoblastic leukemia in a murine transplant model. These findings identify a novel potential therapeutic target in leukemogenesis,and demonstrate the utility of phosphoproteomic strategies for discovery of tyrosine kinase alleles.
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产品类型:
产品号#:
03434
03444
04960
04902
04900
04961
04901
04963
04962
04970
04971
产品名:
MethoCult™ GF M3434
MethoCult™ GF M3434
MegaCult™-C胶原和无细胞因子培养基
胶原蛋白溶液
MegaCult™-C无细胞因子培养基
MegaCult™-C胶原和含细胞因子培养基
MegaCult™-C含细胞因子培养基
双室载玻片套件
MegaCult™-C CFU-Mk染色试剂盒
MegaCult™-C无细胞因子全套试剂盒
MegaCult™-C含细胞因子全套试剂盒
Dobo I et al. (AUG 1995)
Journal of hematotherapy 4 4 281--7
Collagen matrix: an attractive alternative to agar and methylcellulose for the culture of hematopoietic progenitors in autologous transplantation products.
Autografts using untreated or in vitro manipulated bone marrow and peripheral blood stem cells represent promising approaches to the treatment of malignant diseases. In this work,the collagen gel culture technique was compared with agar and methylcellulose for its capacity to permit the growth of human granulomonocytic (day 14 CFU-GM; collagen vs agar or MTC) or erythroblastic (day 7 CFU-E and day 14 BFU-E; collagen versus methylcellulose) colonies in autologous transplantation products. Our results show that the collagen culture system always gave as many or more colonies than the other techniques. It also allowed harvesting of gels onto glass slides and subsequent May-Grünwald-Giemsa,cytochemical or immunocytochemical staining. We suggest that the collagen assay represents an interesting alternative to the widely used agar or methylcellulose systems for the culture of hematopoietic progenitors because of the equal or higher number of colonies detected,the easy phenotypical identification of colonies in stained gels,and the ability to store high-quality documentation. This technique is particularly attractive for use in the quality control of autologous bone marrow transplantation procedures.
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产品类型:
产品号#:
04961
04965
04962
04915
04807
04809
04906
04913
04803
04804
04905
04850
04974
04902
04960
04900
04901
04963
04970
04971
产品名:
MegaCult™-C胶原和含细胞因子培养基
MegaCult™-C CFU-Mk染色试剂盒
MegaCult-C 10% BSA, 6mL
MegaCult-C Human Serum, 6mL
Alkaline Phosphatase Substrate Tabs, pk
Biotin/Conjugate Goat Anti-Mu lgG, 125uL
MegaCult-C Evans Blue Stain, 5mL
Primary Ab, Anti-HuAnti-GPIIb/IIIa 360uL
MegaCult-C Control Antibody, 100 µL
Avidin-Alk Phosphatase Conjugate, 200 uL
MegaCult™-C含脂质培养基
MegaCult™-C胶原和含脂质培养基
胶原蛋白溶液
MegaCult™-C胶原和无细胞因子培养基
MegaCult™-C无细胞因子培养基
MegaCult™-C含细胞因子培养基
双室载玻片套件
MegaCult™-C无细胞因子全套试剂盒
MegaCult™-C含细胞因子全套试剂盒
Hogge D et al. (MAR 1997)
British journal of haematology 96 4 790--800
Quantitation and characterization of human megakaryocyte colony-forming cells using a standardized serum-free agarose assay.
Human progenitors of the megakaryocyte (Mk) lineage were detected by their ability to generate colonies-containing from 3 to textgreater 100 Mk,detectable as glycoprotein IIb/IIIa+ cells in APAAP-stained whole mount agarose cultures. Optimal growth conditions were achieved through the use of a defined serum substitute and a suitable cocktail of recombinant cytokines. Under these culture conditions,the smallest Mk-containing colonies (CFC-Mk) were detectable within a week followed by colonies containing larger numbers of Mk over the ensuing 2 weeks. The total number of CFC-Mk at 18-21 d was linearly related to the number of cells plated. Variation in the cytokines added showed that thrombopoietin (TPO) or IL-3 alone would support the formation of large numbers of CFC-Mk. However,optimal yields of colonies containing cells of both Mk and non-Mk lineages required the addition of other growth factors,of which a combination of IL-3,IL-6,GM-CSF and Steel factor (SF) +/- TPO was the best of those tested. The further addition of erythropoietin to this combination reduced the number of large pure' Mk colonies seen and in their place a corresponding number of mixed erythroid-Mk colonies became detectable. Flt3-ligand alone was unable to support the growth of CFC-Mk nor did it enhance their growth when combined with other factors. Plating of FACS-sorted sub-populations of CD34+ marrow cells in both serum-free agarose and methylcellulose assays demonstrated that most CFC-Mk are generated from CD34+ cells that are CD45RA- and CD71+�
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