Human Tumor Necrosis Factor-α (hTNF-α)

• 产品编号：CST-8902SF      品牌：CST       原厂货号：8902SF
• 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 > TNF Family 肿瘤坏死因子
• 应用分类：

描述：

在CST公司，重组的人TNF-α (hTNF-α) Val77-Leu233 (Accession #HUMTNFAB)是在E. coli中表达产生。重组的hTNF-α蛋白在N-末端无 Met标签，其分子量据推算为17,352Da。DTT-还原和未还原的蛋白迁移时是作为一个18kDa 的多肽而转移。重组hTNF-α蛋白的N-末端序列VRSSS通过测序得到。hTNF-α在溶液中是无二硫键连接的三聚物，而依靠化学连接。6 μg 还原 (+) 和 非还原的(-) hTNF-α通过SDS-PAGE检测，纯度大于98%，所有批次的纯度均高于98%。hTNF-α的生物活性是通过L-929细胞生存能力实验确定的。每个批次的ED50在10-100 pg/ml之间。

有载体: 每微克hTNF-α蛋白溶解在包含 20 μg BSA的PBS（pH 7.2）溶液中，并通过 0.22 μm 滤膜冻干。

无载体：每微克hTNF-α蛋白溶解在PBS（pH 7.2）溶液中，并通过 0.22 μm 滤膜冻干。

TNF-α, TNF家族的典型成员, 是II型的同源三聚体膜蛋白(1,2)。细胞膜锚定的TNF-α通过金属蛋白酶TACE/ADAM17的剪切形成可溶性的同型三聚体(2)。膜锚定和可溶性两种形式都有生物活性。TNF-α可由很多种类的细胞产生包括T细胞、B细胞、巨噬细胞和NK细胞(1)。TNF-α的细胞内响应是通过与 TNF-R1 和 TNF-R2 两个受体互作而介导的并激活细胞存活和细胞凋亡两个截然相反地过程，这两个过程主要决定于细胞的类型和生物学环境。激活激酶的通路(包括JNK, Erk (p44/42), p38 MAPK 和 NF-κB) 促使细胞的存活，TNF-α介导的对caspase-8的激活导致了程序性的细胞死亡(1,2)。TNF-α在炎症反应和宿主抵抗细菌入侵的过程特别是结核分枝杆菌发挥了重要的调控作用(3)。在通过抑制TNF-α来治疗类风湿性关节炎和Crohn’s disease的过程中，TNF-α在自免疫中的作用被低估(1,2,4)。

原厂资料：

Source / Purification

Recombinant human TNF-α (hTNF-α) Val77-Leu233 (Accession #HUMTNFAB) was produced in E. coli at Cell Signaling Technology.

Molecular Characterization

Recombinant hTNF-α does not have a Met on the amino terminus and has a calculated MW of 17,352. DTT-reduced and non-reduced protein migrate as 18 kDa polypeptides. The expected amino-terminal VRSSS of recombinant hTNF-α was verified by amino acid sequencing. TNF-α is a non-disulfide-linked homotrimer in solution as determined by chemical cross-linking.

Purity

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

Bioactivity

The bioactivity of hTNF-α was determined in an L-929 cell viability assay. The ED50 of each lot is between 10-100 pg/ml.

Endotoxin

Less than 0.01 ng endotoxin/1 μg hTNF-α.

Formulation

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

Background

TNF-α, the prototypical member of the TNF protein superfamily, is a homotrimeric type-II membrane protein (1,2). Membrane bound TNF-α is cleaved by the metalloprotease TACE/ADAM17 to generate a soluble homotrimer (2). Both membrane and soluble forms of TNF-α are biologically active. TNF-α is produced by a variety of immune cells including T cells, B cells, NK cells and macrophages (1). Cellular response to TNF-α is mediated through interaction with receptors TNF-R1 and TNF-R2 and results in activation of pathways that favor both cell survival and apoptosis depending on the cell type and biological context. Activation of kinase pathways (including JNK, ERK (p44/42), p38 MAPK and NF-κB) promotes the survival of cells, while TNF-α mediated activation of caspase-8 leads to programmed cell death (1,2). TNF-α plays a key regulatory role in inflammation and host defense against bacterial infection, notably Mycobacterium tuberculosis (3). The role of TNF-α in autoimmunity is underscored by blocking TNF-α action to treat rheumatoid arthritis and Crohn’s disease (1,2,4).

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