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产地 | |
保存条件 | 2-8℃ |
品牌 | Sigma-Aldrich |
货号 | LIF1005 |
用途 | |
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是否是肿瘤细胞 | |
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包装规格 | 5 μg |
是否进口 | 是 |
Key Applications | Species | Source | Purity |
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CULT | Human | LIF is expressed in E. coli as a fusion protein with GST using the pGEX expression system, cleaved from GST moeity with thrombin and purified by HPLC chromatography. | Greater than 95% by analytical HPLC and SDS-PAGE. Endotoxin level is less than 0.1 ng per mg of LIF. Tested negative in both aseptic and microplasmic tests. |
Description | |
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Catalogue Number | LIF1005 |
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Chemicon® |
Trade Name |
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Description | Leukemia Inhibitory Factor human |
Overview | Human LIF is a 19.7 kDa protein containing 181 amino acid residues. The non-glycosylated, E. coli expressed, recombinant human LIF is indistinguishable from native LIF in its biological activities in vitro. Human and murine mature LIF exhibit a 78% sequence identity at the amino acid control. Human LIF is equally active on both human and mouse cells. Murine LIF is approximately 1000 fold less active on human cells, than hLIF. |
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Background Information | Leukemia Inhibitory Factor (LIF) is a lymphoid factor which promotes long-term maintenance of embryonic stem cells by suppressing spontaneous differentiation. LIF has a number of other activities including cholinergic neuron differentiation, control of stem cell pluripotency, bone and fat metabolism, mitogenesis of certain factor dependent cell lines and promotion of megakaryocyte production in vivo. |
Product Information | |
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Presentation | Liquid in PBS, pH 7.4 and 0.02% Tween 20. No preservativies added. |
Quality Level | MQ300 |
Applications | |
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Application | 5 μg, human recombinant LIF protein, expressed in E. coli, suitable for stem cell culture |
Key Applications |
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Application Notes |
RECOMMENDED QC PROTOCOL M1 Bioassay 1. The M1 bioassay is performed using in vitro semi-solid agar cultures, which contain approximately 100 cells in 1 mL volumes of DME containing 20 % FCS in 0.3% agar. 2. Add 100 μL of sample or hLIF (10(E4) units/mL in 5% FCS in isotonic saline) in two-fold serial dilutions in duplicate to 35 mm petri dishes. 3. Add 100 μL of 5% FCS in isotonic saline to two control slides. 4. Incubate at 37°C in fully humidified atmosphere of 10% CO2 in air for 7 days. 5. Score the number of colonies that show differentiation (note: 50 units is defined as the amount of activity which results in 50% of the colonies being differentiated). Manufactured by CHEMICON International, Inc. LIF is protected under US Patent nos. 5,443,825, 5,750,654 and 6,261,548, European Patent no. 0285 448 and related foreign patents and is not available for resale. |
Biological Information | |
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Concentration | 10 μg/mL |
Purity | Greater than 95% by analytical HPLC and SDS-PAGE. Endotoxin level is less than 0.1 ng per mg of LIF. Tested negative in both aseptic and microplasmic tests. |
Source | LIF is expressed in E. coli as a fusion protein with GST using the pGEX expression system, cleaved from GST moeity with thrombin and purified by HPLC chromatography. |
Specific Activity | The activity of human LIF is determined by the ability to induce differentiation of M1 myeloid leukemic cells. The minimum detectable concentration of human LIF in this assay is 0.5 ng/mL. The specific activity is >/=1 x 10(E8) units/mg, where 50 units is defined as the amount of human LIF required to induce differentiation in 50% of the M1 colonies in 1 mL agar cultures. |
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Entrez Gene Summary | Leukaemia inhibitory factor is a cytokine that induces macrophage differentiation. Neurotransmitters and neuropeptides, well known for their role in the communication between neurons, are also capable of activating monocytes and macrophages and inducing chemotaxis in immune cells. LIF signals through different receptors and transcription factors. LIF in conjunction with BMP2 acts in synergy on primary fetal neural progenitor cells to induce astrocytes. |
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UniProt Number |
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UniProt Summary |
FUNCTION: SwissProt: P15018 # LIF has the capacity to induce terminal differentiation in leukemic cells. Its activities include the induction of hematopoietic differentiation in normal and myeloid leukemia cells, the induction of neuronal cell differentiation, and the stimulation of acute-phase protein synthesis in hepatocytes. SIZE: 202 amino acids; 22008 Da SUBCELLULAR LOCATION: Secreted. SIMILARITY: SwissProt: P15018 ## Belongs to the LIF/OSM family. |
Stem Cell Type |
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Product Usage Statements | |
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Usage Statement |
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Storage and Shipping Information | |
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Storage Conditions |
Maintain at 2-8°C for 6 - 12 months. Further dilutions should be made into buffer or medium to which protein (e.g., 1% BSA) or Tween 20 has been added. Manufactured by CHEMICON International, Inc. LIF is protected under US Patent nos. 5,187,077, 5,427,925, 5,443,825, 5,750,654 and 6,261,548, European Patent no. 0285 448 and related foreign patents and is not available for resale. |
Packaging Information | |
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Material Size | 5 μg |