Liu L et al. (AUG 2014)
Biomaterials 35 24 6259--6267
Nanofibrous gelatin substrates for long-term expansion of human pluripotent stem cells.
Nanofibrous gelatin substrates are suited for long-term expansion of human pluripotent stem cells (hPSCs) under feeder- and serum-free culture conditions. A combinatorial library with different sets of processing parameters was established to assess the culture performance of hPSCs on nanofibrous substrates in terms of cell adhesion and growth rate,using Matrigel as control. Then,the optimal conditions were applied to long-term expansion of hPSCs with several cell lines,showing a maintained pluripotency over more than 20 passages without introducing any abnormal chromosome. In addition,this approach allowed us to avoid enzymatic disassociation and mechanic cutting during passages,thereby promoting a better hPSC culture and long-term expansion. ?? 2014 Elsevier Ltd.
View Publication
产品类型:
产品号#:
05850
05857
05870
05875
85850
85857
85870
85875
产品名:
mTeSR™1
mTeSR™1
Yu F et al. (MAY 2011)
Oncogene 30 18 2161--72
Kruppel-like factor 4 (KLF4) is required for maintenance of breast cancer stem cells and for cell migration and invasion.
Kruppel-like factor 4 (KLF4) is highly expressed in more than 70% of breast cancers and functions as an oncogene. However,an exact mechanism by which KLF4 enhances tumorigenesis of breast cancer remains unknown. In this study,we show that KLF4 was highly expressed in cancer stem cell (CSC)-enriched populations in mouse primary mammary tumor and breast cancer cell lines. Knockdown of KLF4 in breast cancer cells (MCF-7 and MDA-MB-231) decreased the proportion of stem/progenitor cells as demonstrated by expression of stem cell surface markers such as aldehyde dehydrogenase 1,side population and by in vitro mammosphere assay. Consistently KLF4 overexpression led to an increase of the cancer stem cell population. KLF4 knockdown also suppressed cell migration and invasion in MCF-7 and MDA-MB-231 cells. Furthermore,knockdown of KLF4 reduced colony formation in vitro and inhibited tumorigenesis in immunocompromised non-obese diabetic/severe combined immunodeficiency mice,supporting an oncogenic role for KLF4 in breast cancer development. Further mechanistic studies revealed that the Notch signaling pathway was required for KLF4-mediated cell migration and invasion,but not for CSC maintenance. Taken together,our study provides evidence that KLF4 has a potent oncogenic role in mammary tumorigenesis likely by maintaining stem cell-like features and by promoting cell migration and invasion. Thus,targeting KLF4 may provide an effective therapeutic approach to suppress tumorigenicity in breast cancer.
View Publication
产品类型:
产品号#:
72782
产品名:
Kenpaullone
Louis SA et al. (JAN 2013)
Methods in molecular biology (Clifton,N.J.) 946 479--506
Methods to culture, differentiate, and characterize neural stem cells from the adult and embryonic mouse central nervous system.
Since the discovery of neural stem cells (NSC) in the embryonic and adult mammalian central nervous system (CNS),there have been a growing numbers of tissue culture media and protocols to study and functionally characterize NSCs and its progeny in vitro. One of these culture systems introduced in 1992 is referred to as the Neurosphere Assay,and it has been widely used to isolate,expand,differentiate and even quantify NSC populations. Several years later because its application as a quantitative in vitro assay for measuring NSC frequency was limited,a new single-step semisolid based assay,the Neural Colony Forming Cell (NCFC) assay was developed to accurately measure NSC numbers. The NCFC assay allows the discrimination between NSCs and progenitors by the size of colonies they produce (i.e.,their proliferative potential). The evolution and continued improvements made to these tissue culture tools will facilitate further advances in the promising application of NSCs for therapeutic use.
View Publication
产品类型:
产品号#:
05700
05701
05715
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™成年中枢神经系统(CNS)组织酶解试剂盒(小鼠和大鼠)
Beamish CA et al. (APR 2016)
Islets 8 3 65--82
Insulin-positive, Glut2-low cells present within mouse pancreas exhibit lineage plasticity and are enriched within extra-islet endocrine cell clusters.
Regeneration of insulin-producing β-cells from resident pancreas progenitors requires an understanding of both progenitor identity and lineage plasticity. One model suggested that a rare β-cell sub-population within islets demonstrated multi-lineage plasticity. We hypothesized that β-cells from young mice (postnatal day 7,P7) exhibit such plasticity and used a model of islet dedifferentiation toward a ductal epithelial-cell phenotype to test this theory. RIPCre;Z/AP(+/+) mice were used to lineage trace the fate of β-cells during dedifferentiation culture by a human placental alkaline phosphatase (HPAP) reporter. There was a significant loss of HPAP-expressing β-cells in culture,but remaining HPAP(+) cells lost insulin expression while gaining expression of the epithelial duct cell marker cytokeratin-19 (Ck19). Flow cytometry and recovery of β-cell subpopulations from whole pancreas vs. islets suggest that the HPAP(+)Ck19(+) cells had derived from insulin-positive,glucose-transporter-2-low (Ins(+)Glut2(LO)) cells,representing 3.5% of all insulin-expressing cells. The majority of these cells were found outside of islets within clusters of <5 β-cells. These insulin(+)Glut2(LO) cells demonstrated a greater proliferation rate in vivo and in vitro as compared to insulin(+)Glut2(+) cells at P7,were retained into adulthood,and a subset differentiated into endocrine,ductal,and neural lineages,illustrating substantial plasticity. Results were confirmed using RIPCre;ROSA- eYFP mice. Quantitative PCR data indicated these cells possess an immature β-cell phenotype. These Ins(+)Glut2(LO) cells may represent a resident population of cells capable of forming new,functional β-cells,and which may be potentially exploited for regenerative therapies in the future.
View Publication
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)
L. Chicaybam et al. ( 2016)
Frontiers in bioengineering and biotechnology 4 99
An Efficient Electroporation Protocol for the Genetic Modification of Mammalian Cells.
Genetic modification of cell lines and primary cells is an expensive and cumbersome approach,often involving the use of viral vectors. Electroporation using square-wave generating devices,like Lonza's Nucleofector,is a widely used option,but the costs associated with the acquisition of electroporation kits and the transient transgene expression might hamper the utility of this methodology. In the present work,we show that our in-house developed buffers,termed Chicabuffers,can be efficiently used to electroporate cell lines and primary cells from murine and human origin. Using the Nucleofector II device,we electroporated 14 different cell lines and also primary cells,like mesenchymal stem cells and cord blood CD34+,providing optimized protocols for each of them. Moreover,when combined with sleeping beauty-based transposon system,long-term transgene expression could be achieved in all types of cells tested. Transgene expression was stable and did not interfere with CD34+ differentiation to committed progenitors. We also show that these buffers can be used in CRISPR-mediated editing of PDCD1 gene locus in 293T and human peripheral blood mononuclear cells. The optimized protocols reported in this study provide a suitable and cost-effective platform for the genetic modification of cells,facilitating the widespread adoption of this technology.
View Publication
产品类型:
产品号#:
04034
04044
22001
22005
22006
22007
22008
22009
22011
22012
22013
产品名:
MethoCult™ H4034 Optimum
MethoCult™ H4034 Optimum
STEMvision™ 人脐带血7-天CFU分析包
STEMvision™ 彩色人脐带血14-天CFU分析包
STEMvision™ 彩色人骨髓14-天CFU分析包
STEMvision™ 彩色人动员外周血14-天CFU分析包
STEMvision™ 小鼠总CFU分析包
STEMvision™ 小鼠髓系CFU分析包
STEMvision™ 小鼠红系CFU分析包
STEMvision™ 小鼠CFU分析包(髓系和红系)
Liu J et al. (NOV 2015)
Nature Protocols 10 11 1842--59
Efficient delivery of nuclease proteins for genome editing in human stem cells and primary cells.
Targeted nucleases,including zinc-finger nucleases (ZFNs),transcription activator-like (TAL) effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9),have provided researchers with the ability to manipulate nearly any genomic sequence in human cells and model organisms. However,realizing the full potential of these genome-modifying technologies requires their safe and efficient delivery into relevant cell types. Unlike methods that rely on expression from nucleic acids,the direct delivery of nuclease proteins to cells provides rapid action and fast turnover,leading to fewer off-target effects while maintaining high rates of targeted modification. These features make nuclease protein delivery particularly well suited for precision genome engineering. Here we describe procedures for implementing protein-based genome editing in human embryonic stem cells and primary cells. Protocols for the expression,purification and delivery of ZFN proteins,which are intrinsically cell-permeable; TALEN proteins,which can be internalized via conjugation with cell-penetrating peptide moieties; and Cas9 ribonucleoprotein,whose nucleofection into cells facilitates rapid induction of multiplexed modifications,are described,along with procedures for evaluating nuclease protein activity. Once they are constructed,nuclease proteins can be expressed and purified within 6 d,and they can be used to induce genomic modifications in human cells within 2 d.
View Publication
产品类型:
产品号#:
05850
05857
05870
05875
07920
17952
17952RF
19052
19052RF
18000
15470
15450
15420
15460
15425
15465
15430
15415
85850
85857
85870
85875
100-0696
07922
产品名:
ACCUTASE™
EasySep™人CD4+ T细胞分选试剂盒
RoboSep™ 人CD4+ T细胞分选试剂盒
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
EasySep™磁极
mTeSR™1
mTeSR™1
EasySep™人CD4+ T细胞分离试剂盒
ACCUTASE™
Safi R et al. (FEB 2009)
Molecular endocrinology (Baltimore,Md.) 23 2 188--201
Pharmacological manipulation of the RAR/RXR signaling pathway maintains the repopulating capacity of hematopoietic stem cells in culture.
The retinoid X receptor (RXR) contributes to the regulation of diverse biological pathways via its role as a heterodimeric partner of several nuclear receptors. However,RXR has no established role in the regulation of hematopoietic stem cell (HSC) fate. In this study,we sought to determine whether direct modulation of RXR signaling could impact human HSC self-renewal or differentiation. Treatment of human CD34(+)CD38(-)lin(-) cells with LG1506,a selective RXR modulator,inhibited the differentiation of HSCs in culture and maintained long-term repopulating HSCs in culture that were otherwise lost in response to cytokine treatment. Further studies revealed that LG1506 had a distinct mechanism of action in that it facilitated the recruitment of corepressors to the retinoic acid receptor (RAR)/RXR complex at target gene promoters,suggesting that this molecule was functioning as an inverse agonist in the context of this heterodimer. Interestingly,using combinatorial peptide phage display,we identified unique surfaces presented on RXR when occupied by LG1506 and demonstrated that other modulators that exhibited these properties functioned similarly at both a mechanistic and biological level. These data indicate that the RAR/RXR heterodimer is a critical regulator of human HSC differentiation,and pharmacological modulation of RXR signaling prevents the loss of human HSCs that otherwise occurs in short-term culture.
View Publication
产品类型:
产品号#:
04434
04444
产品名:
MethoCult™ H4434 Classic
MethoCult™ H4434 Classic
De Palma M et al. (MAR 2005)
Blood 105 6 2307--15
Promoter trapping reveals significant differences in integration site selection between MLV and HIV vectors in primary hematopoietic cells.
Recent reports have indicated that human immunodeficiency virus (HIV) and murine leukemia virus (MLV) vectors preferentially integrate into active genes. Here,we used a novel approach based on genetic trapping to rapidly score several thousand integration sites and found that MLV vectors trapped cellular promoters more efficiently than HIV vectors. Remarkably,1 in 5 MLV integrations trapped an active promoter in different cell lines and primary hematopoietic cells. Such frequency was even higher in growth-stimulated lymphocytes. We show that the different behavior of MLV and HIV vectors was dependent on a different integration pattern within transcribed genes. Whereas MLV-based traps showed a strong bias for promoter-proximal integration leading to efficient reporter expression,HIV-based traps integrated throughout transcriptional units and were limited for expression by the distance from the promoter and the reading frame of the targeted gene. Our results indicate a strong propensity of MLV to establish transcriptional interactions with cellular promoters,a behavior that may have evolved to enhance proviral expression and may increase the insertional mutagenesis risk. Promoter trapping efficiency provides a convenient readout to assess transcriptional interactions between the vector and its flanking genes at the integration site and to compare integration site selection among different cell types and in different growth conditions.
View Publication
产品类型:
产品号#:
03434
03444
09600
09650
18757
18757RF
产品名:
MethoCult™ GF M3434
MethoCult™ GF M3434
StemSpan™ SFEM
StemSpan™ SFEM
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
Eggimann L et al. (MAY 2015)
Bone marrow transplantation 50 5 743--5
Kinetics of peripheral blood chimerism for surveillance of patients with leukemia and chronic myeloid malignancies after reduced-intensity conditioning allogeneic hematopoietic SCT.
Romanov YA et al. (JAN 2003)
Stem cells (Dayton,Ohio) 21 1 105--10
Searching for alternative sources of postnatal human mesenchymal stem cells: candidate MSC-like cells from umbilical cord.
Mesenchymal stem cells (MSCs) have the capability for renewal and differentiation into various lineages of mesenchymal tissues. These features of MSCs attract a lot of attention from investigators in the context of cell-based therapies of several human diseases. Despite the fact that bone marrow represents the main available source of MSCs,the use of bone marrow-derived cells is not always acceptable due to the high degree of viral infection and the significant drop in cell number and proliferative/differentiation capacity with age. Thus,the search for possible alternative MSC sources remains to be validated. Umbilical cord blood is a rich source of hematopoietic stem/progenitor cells and does not contain mesenchymal progenitors. However,MSCs circulate in the blood of preterm fetuses and may be successfully isolated and expanded. Where these cells home at the end of gestation is not clear. In this investigation,we have made an attempt to isolate MSCs from the subendothelial layer of umbilical cord vein using two standard methodological approaches: the routine isolation of human umbilical vein endothelial cell protocol and culture of isolated cells under conditions appropriate for bone-marrow-derived MSCs. Our results suggest that cord vasculature contains a high number of MSC-like elements forming colonies of fibroblastoid cells that may be successfully expanded in culture. These MSC-like cells contain no endothelium- or leukocyte-specific antigens but express alpha-smooth muscle actin and several mesenchymal cell markers. Therefore,umbilical cord/placenta stroma could be regarded as an alternative source of MSCs for experimental and clinical needs.
View Publication
产品类型:
产品号#:
产品名:
Wagner W et al. (OCT 2007)
Stem cells (Dayton,Ohio) 25 10 2638--47
Molecular and secretory profiles of human mesenchymal stromal cells and their abilities to maintain primitive hematopoietic progenitors.
Mesenchymal stromal cells (MSC) provide a supportive cellular microenvironment and are able to maintain the self-renewal capacity of hematopoietic progenitor cells (HPC). Isolation procedures for MSC vary extensively,and this may influence their biologic properties. In this study,we have compared human MSC isolated from bone marrow (BM) using two culture conditions,from cord blood (CB),and from adipose tissue (AT). The ability to maintain long-term culture-initiating cell frequency and a primitive CD34(+)CD38(-) immunophenotype was significantly higher for MSC derived from BM and CB compared with those from AT. These results were in line with a significantly higher adhesion of HPC to MSC from BM and CB versus MSC from AT. We have compared the cytokine production of MSC by cytokine antibody arrays,enzyme-linked immunosorbent assay,and a cytometric bead array. There were reproducible differences in the chemokine secretion profiles of various MSC preparations,but there was no clear concordance with differences in their potential to maintain primitive function of HPC. Global gene expression profiles of MSC preparations were analyzed and showed that adhesion proteins including cadherin-11,N-cadherin,vascular cell adhesion molecule 1,neural cell adhesion molecule 1,and integrins were highly expressed in MSC preparations derived from BM and CB. Thus,MSC from BM and CB are superior to MSC from AT for maintenance of primitive HPC. The latter property is associated with specific molecular profiles indicating the significance of cell-cell junctions but not with secretory profiles. Disclosure of potential conflicts of interest is found at the end of this article.
View Publication
产品类型:
产品号#:
05401
05402
05411
产品名:
MesenCult™ MSC 基础培养基(人)
MesenCult™ MSC 刺激补充剂(人)
MesenCult™ 增殖试剂盒(人)
Sutherland HJ et al. (MAY 1990)
Proceedings of the National Academy of Sciences of the United States of America 87 9 3584--8
Functional characterization of individual human hematopoietic stem cells cultured at limiting dilution on supportive marrow stromal layers.
A major goal of current hematopoiesis research is to develop in vitro methods suitable for the measurement and characterization of stem cells with long-term in vivo repopulating potential. Previous studies from several centers have suggested the presence in normal human or murine marrow of a population of very primitive cells that are biologically,physically,and pharmacologically different from cells detectable by short-term colony assays and that can give rise to the latter in long-term cultures (LTCs) containing a competent stromal cell layer. In this report,we show that such cultures can be used to provide a quantitative assay for human LTC-initiating cells" based on an assessment of the number of clonogenic cells present after 5-8 weeks. Production of derivative clonogenic cells is shown to be absolutely dependent on the presence of a stromal cell feeder. When this requirement is met�
View Publication