ProSpec-IFN a 2b Human/CYT-205

IFN alpha 2b, IFNA, INFA2, MGC125764, MGC125765.

IFN-alpha is produced by macrophages and has antiviral activities. IFN stimulates the production of two enzymes: protein kinase and an oligoadenylate synthetase.

IFN-a 2b Human Recombinant produced in E.Coli is a single, non-glycosylated, polypeptide chain containing 166 amino acids and having a molecular mass of 19400 Dalton. The difference between IFNA2A and IFNA2B is in the amino acid present at position 23. IFN-alpha 2a has a lysine at that position 23 while IFN-alpha 2b has arginine.

The IFN-alpha 2b gene was obtained from human leukocytes.

The IFN-a 2b is purified by proprietary chromatographic techniques.

在大肠杆菌中产生的 IFN-a 2b Human Recombinant 是一种单一的、非糖基化的多肽链，包含 166 个氨基酸，分子量为 19400 道尔顿。 IFNA2A 和 IFNA2B 之间的区别在于第 23 位存在的氨基酸。IFN-α2a 在第 23 位具有赖氨酸，而 IFN-α2b 具有精氨酸。

IFN-α2b 基因是从人类白细胞中获得的。

IFN-a 2b 通过专有色谱技术进行纯化。

Escherichia Coli.

Sterile Filtered White lyophilized powder.

Lyophilized from a solution in containing 2.3 mg Sodium phosphate dibasic and 0.55 mg sodium phosphate monobasic buffer.

It is recommended to reconstitute the lyophilized IFN-alpha 2b in sterile 18MΩ-cm H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.

Lyophilized IFN although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution IFN alpha 2b should be stored at 4°C between 2-7 days and for future use below -18°C.
For long term storage it is recommended to add a carrier protein .
Please prevent freeze-thaw cycles.

冻干的 IFN 虽然在室温下可稳定保存 3 周，但应在 -18°C 以下干燥储存。 重构后，IFN α 2b 应在 4°C 下储存 2-7 天，以备将来在低于 -18°C 的温度下使用。
对于长期储存，建议添加载体蛋白。
请防止冻融循环。

Greater than 98.0% as determined by Analysis by RP-HPLC.
Analysis by -PAGE.

MCDLPQTHSL GSRRTLMLLA QMRRISLFSC LKDRHDFGFP QEEFGNQFQK AETIPVLHEM IQQIFNLFST KDSSAAWDET LLDKFYTELY QQLNDLEACV IQGVGVTETP LMKEDSILAV RKYFQRITLY LKEKKYSPCA WEVVRAEIMR SFSLSTNLQE SLRSKE

The specific activity as determined in a viral resistance assay using bovine kidney MDBK cells was found to be 260,000,000 IU/ mg.

Protein quantitation was carried out by two independent methods
1. UV spectroscopy at 280 nm using the absorbency value of 0.924 as the extinction coefficient for a 0.1% solution. This value is calculated by the PC GENE computer analysis program of protein sequences .

2. Analysis by RP-HPLC, using a calibrated solution of IFN alpha 2b as a Reference Standard.

通过两种独立的方法进行蛋白质定量
1. 280 nm 的紫外光谱，使用 0.924 的吸光度值作为 0.1% 溶液的消光系数。 该值是由 PC GENE 计算机蛋白质序列分析程序计算得出的。

2. 通过 RP-HPLC 分析，使用 IFN α 2b 的校准溶液作为参考标准。

Title:IFN-β induces apoptosis in human SH-SY5Y neuroblastoma cells through activation of JAK–STAT signaling and down-regulation of PI3K/Akt pathway.
Publication:Article first published online: 11 NOV 2010 DOI:10.1111/j.1471-4159.2010.07046.x © 2010 The Authors. Journal of Neurochemistry © 2010 International Society for Neurochemistry.
Link:http://onlinelibrary.wiley.com/doi/10.1111/j.1471-4159.2010.07046.x/full

ProSpec’s products are furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals.

IFN-alpha forms are produced by monocytes/macrophages, lymphoblastoid cells, fibroblasts, and a number of different cell types following induction by viruses, nucleic acids, glucocorticoid hormones, and low-molecular weight substances . At least 23 different variants of IFN-alpha are known. The individual proteins have molecular masses between 19-26 kDa and consist of proteins with lengths of 156-166 and 172 amino acids. All IFN-alpha subtypes possess a common conserved sequence region between amino acid positions 115-151 while the amino-terminal ends are variable. Many IFN-alpha subtypes differ in their sequences at only one or two positions. Naturally occurring variants also include proteins truncated by 10 amino acids at the carboxy-terminal end. Disulfide bonds are formed between cysteines at positions 1/98 and 29/138. The disulfide bond 29/138 is essential for biological activity while the 1/98 bond can be reduces without affecting biological activity. All IFN-alpha forms contain a potential glycosylation site but most subtypes are not glycosylated. In contrast to IFN-gamma IFN-alpha proteins are stable at pH2.

There are at least 23 different IFN-alpha genes. They have a length of 1-2 kb and are clustered on human chromosome 9p22. It is not known whether all these genes are expressed following stimulation of the cells. In some cell systems expression of some subtypes is stronger than those of others. IFN-alpha genes do not contain intron sequences found in many other eukaryotic genes . Based upon the structures two types of IFN-alpha genes, designated class 1 and II, are distinguished. They encode proteins of 156-166 and172 amino acids, respectively. Deletions covering 9p22 are observed frequently in cells of lymphoblastoid leukemias. It is not known to date whether this is of significance with respect to IFN expression.

The gene encoding the IFN-alpha receptor maps to human chromosome 21q22.1. IFN-alpha and IFN-beta are thought to bind to the same IFN binding subunit which is expressed in 100-5000 copies in IFN-alpha sensitive and -resistant cells and is associated with other as yet unidentified proteins. The IFN-omega also binds to the IFN-alpha/IFN-beta receptor. Another receptor expressed on B-lymphocytes is identical with CD21. This receptor also binds Epstein-Barr virus through its gp350/220 coat protein.Signal transduction mechanisms elicited after binding of IFN-alpha to its receptors involves tyrosine phosphorylation of various non-receptor tyrosine kinases belonging to the Janus kinases. Soluble forms of the IFN-alpha receptor, corresponding to truncated forms of the extracellular domain of the cell surface IFN-alpha receptor, have been found in human serum and in normal human urine.

All known subtypes of IFN-alpha show the same antiviral antiparasitic, antiproliferative activities in suitable bioassays although they may differ in relative activities. Human IFN-alpha is also a potent antiviral substance in murine, porcine, and bovine cell systems. Human IFN-alpha is less active in rodent cells. Site-directed mutagenesis techniques have been used to create some variants of certain subtypes that display approximately 100-fold enhanced antiviral activities in mouse cells.

IFN-α 形式由单核细胞/巨噬细胞、类淋巴母细胞、成纤维细胞和许多不同类型的细胞在病毒、核酸、糖皮质激素和低分子量物质诱导后产生。已知至少 23 种不同的 IFN-α 变体。单个蛋白质的分子量在 19-26 kDa 之间，由长度为 156-166 和 172 个氨基酸的蛋白质组成。所有 IFN-α 亚型在氨基酸位置 115-151 之间具有共同的保守序列区域，而氨基末端是可变的。许多 IFN-α 亚型的序列仅在一个或两个位置上有所不同。天然存在的变体还包括在羧基末端被 10 个氨基酸截短的蛋白质。在 1/98 和 29/138 位的半胱氨酸之间形成二硫键。二硫键 29/138 对生物活性至关重要，而 1/98 键可以还原而不影响生物活性。所有 IFN-α 形式都含有潜在的糖基化位点，但大多数亚型未糖基化。与 IFN-γ 相比，IFN-α 蛋白在 pH2 下是稳定的。

至少有 23 种不同的 IFN-α 基因。它们的长度为 1-2 kb，聚集在人类染色体 9p22 上。不知道所有这些基因是否在细胞刺激后表达。在某些细胞系统中，某些亚型的表达强于其他亚型。 IFN-α 基因不包含在许多其他真核基因中发现的内含子序列。根据结构区分两种类型的 IFN-α 基因，称为 1 类和 II 类。它们分别编码 156-166 和 172 个氨基酸的蛋白质。在淋巴母细胞白血病细胞中经常观察到覆盖 9p22 的缺失。迄今为止尚不清楚这对于 IFN 表达是否重要。

编码 IFN-α 受体的基因映射到人类染色体 21q22.1。 IFN-α 和 IFN-β 被认为与相同的 IFN 结合亚基结合，该亚基在 IFN-α 敏感和抗性细胞中以 100-5000 个拷贝表达，并与其他尚未鉴定的蛋白质相关。 IFN-ω 还与 IFN-α/IFN-β 受体结合。 B 淋巴细胞上表达的另一种受体与 CD21 相同。该受体还通过其 gp350/220 外壳蛋白与 Epstein-Barr 病毒结合。在 IFN-α 与其受体结合后引发的信号转导机制涉及属于 Janus 激酶的各种非受体酪氨酸激酶的酪氨酸磷酸化。已在人血清和正常人尿中发现可溶形式的 IFN-α 受体，对应于细胞表面 IFN-α 受体胞外结构域的截短形式。

所有已知的 IFN-α 亚型在合适的生物测定中显示出相同的抗病毒、抗寄生虫、抗增殖活性，尽管它们的相对活性可能不同。人 IFN-α 在鼠、猪和牛细胞系统中也是一种有效的抗病毒物质。人 IFN-α 在啮齿动物细胞中的活性较低。定点诱变技术已被用于产生某些亚型的一些变体，这些变体在小鼠细胞中显示出大约 100 倍增强的抗病毒活性。