Human Latent Transforming Growth Factor β1 (hLatent TGF-β1)

• 产品编号：CST-5154LC      品牌：CST       原厂货号：5154LC
• 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 > TGF-beta 转化生长因子beta超家族
• 应用分类：

描述：

Cell Signaling Technology使用人293T细胞表达重组人latent TGF-β1 (hLatent TGF-β1) Leu30-Ser390 (Accession #P01137)。重组hLatent TGF-β1没有标签，计算得到非糖基化的小潜在TGF-β1复合物分子量为41,251。DTT-还原蛋白迁移率显示其包含两条多肽分别为40和13kDa，非还原状态以半胱氨酸连接形成的同二聚体显示蛋白分别为80和25kDa。重组hTGF-β1氨基端序列ALDTN和重组LAP氨基端序列LSTSK通过氨基酸测序确认。通过抑制IL-4诱导HT-2细胞增殖的实验，以检测重组蛋白hLatent TGF-β1的生物活性。各批次产品经酸激活后ED50在4-10 ng/ml 和 0.2-0.8 ng/ml之间。带载体： 0.25 mg/ml hLatent TGF-β1溶于pH 7.2，25% (v/v) glycerol 的PBS溶液使1 μg hLatent TGF-β1携带20 μg BSA，溶液经0.22um滤器过滤获得。无载体：0.25 mg/ml hLatent TGF-β1溶于含有25% (v/v) glycerol pH 7.2 的PBS溶液经0.22um滤器过滤获得。潜伏的TGF-β1是两个蛋白组成的复合物，潜伏相关蛋白（LAP）和TGF-β1，TGF-β1由一个75 kDa的前体蛋白的剪切后得到（1）。LAP蛋白可以时空特异性的调控TGF-β1，它促进TGF-β1蛋白与潜在TGF-β1结合蛋白（LTBP）结合，使其留在细胞外基质中（1）。一系列的刺激包括蛋白酶，凝血酶敏感蛋白1，活性氧和一些整合素都可以激活TGF-β1的释放（1）。有活性的TGF-β1与TβRII同二聚体结合，随后再与TβRI同二聚体形成复合物（2,3）。这种低聚受体复合物可以磷酸化Smad蛋白以激活或抑制多种靶基因表达（3-5）。TGF-β1的结合也可以通过TAK1激活Erk2, p38, 和Jnk信号通路（5）。有活性的TGF-β1的功能包括增殖，血管生成和促进或抑制许多免疫反应（2,4,5）。潜伏的TGF-β1与GARP关联由调节T细胞呈递至细胞表面，可能与免疫抑制反应直接相关（6,7）。

原厂资料：

Source / Purification

Recombinant human latent TGF-β1 (hLatent TGF-β1) Leu30-Ser390 (Accession #P01137) was expressed in human 293 cells at Cell Signaling Technology.

Molecular Characterization

Recombinant hLatent TGF-β1 contains no "tags" and the nonglycosylated small latent TGF-β1 complex has a calculated MW of 41,251. DTT-reduced protein migrates as 40 and 13 kDa polypeptides, and the non-reduced cystine-linked homodimers migrate as 80 and 25 kDa proteins. The expected amino-terminal ALDTN of recombinant hTGF-β1 and the expected amino-terminal LSTSK of recombinant latency-associated peptide (LAP) were verified by amino acid sequencing.

Purity

>98% as determined by SDS-PAGE of 6 μg reduced (+) and non-reduced (-) recombinant hLatent TGF-β1. All lots are greater than 98% pure.

Bioactivity

The bioactivity of recombinant hLatent TGF-β1 was determined by assessing inhibition of IL-4 induced HT-2 cell proliferation. The ED50 of each lot is between 4-10 ng/ml and 0.2-0.8 ng/ml after acid activation.

Endotoxin

Less than 0.01 ng endotoxin/1 μg hLatent TGF-β1.

Formulation

With carrier: A 0.22 μm filtered solution of 0.25 mg/ml hLatent TGF-β1 in PBS, pH 7.2 and 25% (v/v) glycerol containing 20 μg BSA per 1 μg hLatent TGF-β1. Carrier free: A 0.22 μm filtered solution of 0.25 mg/ml hLatent TGF-β1 in PBS, pH 7.2 and 25% (v/v) glycerol.

Background

Latent TGF-β1 is a complex of two proteins, latency associated protein (LAP) and TGF-β1, which is derived from cleavage of a common 75 kDa precursor protein (1). The LAP protein spatially and temporally regulates TGF-β1 activity by sequestering TGF-β1 in the extracellular matrix in conjunction with latent TGF-β1 binding proteins (LTBP)(1). The release of TGF-β1 is activated by a number of stimuli including proteases, thrombospondin-1, reactive oxygen species, and some integrins (1). Active TGF-β1 binds to TβRII homodimer, which then complexes with TβRI homodimer (2,3). The oligomeric receptor complex phosphorylates subsets of the Smad proteins that then act to induce or repress a number of target genes (3-5). TGF-β1 binding can also activate the Erk2, p38, and Jnk pathways via TAK1 (5). Active TGF-β1 activities include proliferation, angiogenesis, and promotion or inhibition of many immune events (2,4,5). Latent TGF-β1 is present on the surface of regulatory T cells in association with GARP and may contribute directly to their immunosuppressive activity (6,7).

注意事项：

Storage: Stable at -20ºC for 1 year after receipt. Maintain steril-
ity. Storage at -20ºC should be in a manual defrost freezer.