Human Leukemia Inhibitory Factor (hLIF)

• 产品编号：CST-8911LC      品牌：CST       原厂货号：8911LC
• 产品分类：蛋白质检测与分析 > 蛋白质，多肽和酶 > 细胞因子和生长因子 > 其它细胞因子和生长因子
• 应用分类：

描述：

重组人LIF (hLIF) Ser23-Phe202 (Accession #P15018)由 CST公司在大肠杆菌中进行表达。根据氨基酸测序，超过30%的重组hLIF在氨基端Ser23有一个蛋氨酸（MSPLP），分子量为19,847。残余部分从Ser23（SPLPI）、Pro24 (PLPIT)或Pro26 (PITPV)开始。DTT还原的蛋白接近20kDa多肽的迁移位置，由于分子内的胱氨酸，非还原的蛋白接近17kDa多肽的迁移位置。用6 μg还原的(+)和非还原的(-)重组hLIF进行SDS-PAGE，纯度都大于98%。所有批次的产品纯度都大于98%。用TF-1细胞增殖试验进行重组hLIF的生物活性测定。每个批次的ED50在0.2-1.5 ng/ml之间。每微克hLIF内毒素含量小于0.01ng。

有载体：每微克hLIF溶解在包含 20 μg BSA的PBS （pH 7.2）溶液中，并通过 0.22 μm 滤膜过滤后冻干。

无载体：每微克hLIF溶解在PBS （pH 7.2）溶液中，，并通过 0.22 μm 滤膜过滤后冻干。

白血病抑制因子(LIF)是一个20kDa的多向性因子，属于IL-6细胞因子超家族（1）。LIF在许多组织和细胞中都有表达。LIF受体是异源二聚体，包含LIF-R (gp190) 和gp130，是IL-6型细胞因子通用的信号转导蛋白（1）。依据细胞类型的不同，LIF/LIF-R能激活Erk，PI3K和 Jak1/Stat1/3通路（1,2）。LIF有不同的生物活性。鼠类胚胎干细胞在体外的多能性和自我更新依赖LIF（1）。肌肉中由运动诱导分泌的LIF能诱导肌母细胞增殖，说明LIF可能在运动诱导的肌肥厚中起了一定的作用（2）。LIF还能对Th2和Th17细胞分化进行负调节（3,4）。

原厂资料：

Source / Purification

Recombinant human LIF (hLIF) Ser23-Phe202 (Accession #P15018) was produced in E. coli at Cell Signaling Technology.

Molecular Characterization

Based on amino acid sequencing, greater than 30% of recombinant hLIF has a Met on the amino-terminal Ser23 (MSPLP) and has a calculated MW of 19,847. The remainder starts at Ser23 (SPLPI), Pro24 (PLPIT), or Pro26 (PITPV). DTT-reduced protein migrates as a 20 kDa polypeptide and non-reduced protein migrates as a 17 kDa polypeptide due to intramolecular cystitis.

Purity

>98% as determined by SDS-PAGE of 6 μg reduced (+) and non-reduced (-) recombinant hLIF. All lots are greater than 98% pure.

Bioactivity

The bioactivity of recombinant hLIF was determined in a TF-1 cell proliferation assay. The ED50 of each lot is between 0.2-1.5 ng/ml.

Endotoxin

Less than 0.01 ng endotoxin/1 μg hLIF.

Formulation

With carrier: Lyophilized from a 0.22 μm filtered solution of PBS, pH 7.2 containing 20 μg BSA per 1 μg hLIF. Carrier free: Lyophilized from a 0.22 μm filtered solution of PBS, pH 7.2.

Background

Leukemia Inhibitory Factor (LIF) is a 20 kDa pleiotrophic factor belonging to the IL-6 superfamily of cytokines (1). LIF is expressed in a number of tissues and cell types. The LIF receptor is a heterodimer comprised of LIF-R (gp190) and gp130, a common signal transducer for IL-6-type cytokines (1). Depending on cell type and context, LIF/LIF-R can activate Erk, PI3K, and Jak1/Stat1/3 pathways (1,2). LIF has a diverse array of biological activities. Murine embryonic stem cells are dependent on LIF for pluripotency and self-renewal in vitro (1). Exercise- induced LIF secretion in muscle induces myoblast proliferation, suggesting that LIF may play a role in exercise-induced muscle hypertrophy (2). LIF also negatively regulates Th2 and Th17 cell differentiation (3,4).

注意事项：

 Storage: Stable in lyophilized state at 4ºC for 1 year after
receipt. Sterile stock solutions reconstituted with carrier protein
are stable at 4ºC for 2 months and at -20ºC for 6 months. Avoid
repeated freeze-thaw cycles.