人白介素12重组蛋白

中文名:白介素12
英文名:Interleukin 12

简介
白细胞介素-12(IL-12)是一种是具有广泛生物学活性的细胞因子,由p35和p40(IL-12β)两条链组成的异源二聚体蛋白,两个亚单位通过二硫键连接在一起。IL-12主要是激活的炎性细胞(单核-巨噬细胞、树突状细胞和其他抗原呈递细胞)产生的。细菌、胞内寄生虫、真菌微生物的产物都是IL-12生成的强有力的诱导剂,不同的细胞因子如IFN-γ、TNF-β、GM-CSF能增强细胞产生IL-12的能力。
 IL-12主要作用于淋巴细胞,IL-12是Th1细胞免疫应答的决定因素,可有效地促进Th1类细胞因子如IFN-γ的产生,另一方面又可抑制Th2类因子如IL-4、IL-13的产生,从而抑制Th2型应答反应。IL-12的减少或缺失导致Th2优势免疫反应。IL-12是最强的诱导T淋巴细胞特别是活化的T细胞和NK细胞产生IFN-γ的细胞因子,IL-12的许多体内作用就是通过诱导IFN-γ的产生来发挥的。IL-12还能增强细胞毒性T淋巴细胞(CTLs)和LAK细胞的生成,同时,通过诱导编码细胞毒颗粒相关分子基因的转录和通过上调黏附分子的表达,它也能增加CTLs和NK细胞的细胞毒活性。IL-12还能直接影响B细胞的增殖分化,对B细胞的活化作用和诱导特定免疫球蛋白同种型(IgG增加,IgE减少)生成的效应。

清泓制备的人IL12重组蛋白,源自哺乳动物细胞表达系统,通过共表达p35和p40亚基,实现2个亚基在细胞内完成组装和修饰,分泌到细胞培养基上清中,经过纯化制备得到的最近似生理状态的IL12蛋白。

Catalog No. PM007
Accession: IL12A, NP_000873.2. ; IL12B, NP_002178.2.
Protein name: Recommended name: Interleukin-12
Alternative name(s): Cytotoxic lymphocyte maturation factor, NK cell stimulatory factor chain 1

Summaries:
Entrez Gene summary for IL12A:
This gene encodes a subunit of a cytokine that acts on T and natural killer cells, and has a broad array of biological activities. The cytokine is a disulfide-linked heterodimer composed of the 35-kD subunit encoded by this gene, and a 40-kD subunit that is a member of the cytokine receptor family. This cytokine is required for the T-cell-independent induction of interferon (IFN)-gamma, and is important for the differentiation of both Th1 and Th2 cells. The responses of lymphocytes to this cytokine are mediated by the activator of transcription protein STAT4. Nitric oxide synthase 2A (NOS2A/NOS2) is found to be required for the signaling process of this cytokine in innate immunity. (provided by RefSeq, Jul 2008)
Entrez Gene summary for IL12B:
This gene encodes a subunit of interleukin 12, a cytokine that acts on T and natural killer cells, and has a broad array of biological activities. Interleukin 12 is a disulfide-linked heterodimer composed of the 40 kD cytokine receptor like subunit encoded by this gene, and a 35 kD subunit encoded by IL12A. This cytokine is expressed by activated macrophages that serve as an essential inducer of Th1 cells development. This cytokine has been found to be important for sustaining a sufficient number of memory/effector Th1 cells to mediate long-term protection to an intracellular pathogen. Overexpression of this gene was observed in the central nervous system of patients with multiple sclerosis (MS), suggesting a role of this cytokine in the pathogenesis of the disease. The promoter polymorphism of this gene has been reported to be associated with the severity of atopic and non-atopic asthma in children. (provided by RefSeq, Jul 2008)

Function:
Cytokine that can act as a growth factor for activated T and NK cells, enhance the lytic activity of NK/lymphokine-activated Killer cells, and stimulate the production of IFN-gamma by resting PBMC.

Description:   
Recombinant heterodimeric Human IL12 protein (IL12A co-transfected with IL12B) was produced in mammalian cells with C-terminal His tag at IL12A protein. The molecular weight of purified IL12a is 23.64 kDa, and MW of IL12b is 34.69 kDa. Purified IL12 heterodimer protein is at the position of 80 kDa on SDS-PAGE gel under non-reduced condition.
IL12 protein is purified by proprietary chromatographic techniques.

Source:
Mammalian cells, HEK293.

Physical Appearance:
Sterile Filtered clear solution.

Formulation:
Protein is supplied in 50 mM Tris,150 mM NaCl, 10% Glycerol, pH 7.5

Amino Acid Sequence:   
IL12a-His (N-terminal 22 aa is predicted to be signal peptide):
MCPARSLLLVATLVLLDHLSLARNLPVATPDPGMFPCLHHSQNLLRAVSNMLQKARQTLEFYPCTSEEIDHEDITKDKTSTVEA
CLPLELTKNESCLNSRETSFITNGSCLASRKTSFMMALCLSSIYEDLKMYQVEFKTMNAKLLMDPKRQIFLDQNMLAVIDELM
QALNFNSETVPQKSSLEEPDFYKTKIKLCILLHAFRIRAVTIDRVMSYLNASHHHHHHHH
IL12b (N-terminal 22 aa is predicted to be signal peptide):
MCHQQLVISWFSLVFLASPLVAIWELKKDVYVVELDWYPDAPGEMVVLTCDTPEEDGITWTLDQSSEVLGSGKTLTIQVKEFG
DAGQYTCHKGGEVLSHSLLLLHKKEDGIWSTDILKDQKEPKNKTFLRCEAKNYSGRFTCWWLTTISTDLTFSVKSSRGSSDPQ
GVTCGAATLSAERVRGDNKEYEYSVECQEDSACPAAEESLPIEVMVDAVHKLKYENYTSSFFIRDIIKPDPPKNLQLKPLKNSRQ
VEVSWEYPDTWSTPHSYFSLTFCVQVQGKSKREKKDRVFTDKTSATVICRKNASISVRAQDRYYSSSWSEWASVPCS

Usage:
This product is furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals.