
Product Specifications:
Item# 105-10: Recombinant M Tuberculosis ESAT-6 Antigen (E.coli)
Concentration: 2mg/vial
Mass/vial: 1mg
Volume/vial: 500ul
Diluent: 50mM NaPO4, pH 7.0, 0.1M NaCl , 0.05% Sod. Sarcosyl >98%
Purity: >98%
Stabilizer: None
Preservative: None
Storage: -75°C
Physical State: Liquid, sterile filled
Stability: 2 year at -75°C
Applications: ELISA, Western ELISA, TB, Diagnostics.
Description: M Tuberculosis ESAT-6 Antigen produced in the E. coli expression system.
Purification: Purified by ion affinity and UF concentration solvent extraction to >98% purity as determined by SDS-PAGE.
Molecular Weight: 13kD
Specificity: This ESAT-6 protein reacts with human TB serum in ELISA and Western ELISA.
Biological Activity: Not determined
Application and Instructions for use:
Recommended concentrations for use are approximate values. A dose dependent response assay should be performed to determine the optimal concentration for use in specific applications.
ELISA and Western ELISA require 10-100ng protein depending on the nature and affinity of the detection reagent. Human serum polyclonal antibodies yield titers of 1:1000 or greater at 100ng of immobilized protein under standard ELISA conditions.
Region of difference 1 to 3 gene
Glossary
Gene and Gene Products
Structural Proteins: Structural proteins – the products of gag, pol and env genes, which are essential components of the retroviral particle.
Regulatory Proteins: Regulatory proteins – tat and rev proteins of HIV/SIV and tax and rex proteins of HTLVs; essential for viral expression in infected cells.
Accessory Proteins: Accessory proteins – additional (non-regulatory) virion – and non virion-associated proteins produced by HIV/SIV retroviruses: vif, vpr, vpu, vpx, and nef. Although, the accessory proteins are not necessary for viral propagation in tissue culture, they have been conserved in the different isolates; this conservation and experimental observations suggest that their role in vivo is very important.
gag
gag – group-sepecifc antigens or capsid proteins; the precursor is the p55 myristoylated protein, which is processed to p17 (Matrix) p24 (Capsid) and p7 (NucleoCapsid) proteins by the viral protease. Other small proteins are generated from the gag polyprotein.
pol
pol – (p66) generates the viral enzymes protease (p11), reverse transcriptase (p51), endonuclease and integrase (p32) after the processing of a gag-pol precursor polyprotein by the viral protease; gag-pol precursor is produced by ribosome frameshifting.
env
env – viral glycoproteins produced as a precursor (gp160) and processed to the external glycoprotein (gp120) and the transmembrane glycoprotein (gp41). The mature proteins are held together by noncovalent interactions; as a result substantial amount of gp120 is released extracellularly. The external glycoprotein (gp120) contains the binding site for the CD4 receptor.
tat
tat – transactivator of HIV gene expression; one of the two necessary viral regulatory factors (tat and rev) for HIV gene expression. Two forms are known, tat-1 exon (minor form) of 72 amino acids, and tat-2 exon (major form) of 86 amino acids. The electrophoretic mobility of these two forms in SDS gels is anomalous; they are approximately 16 kD and 14 kD in weight. Low levels of both proteins are found in persistently infected cells. tat is localized primarily in the nucleolus/nucleus; it acts by binding to the TAR RNA element and activating transcription from the LTR promoter. Post-transcriptional effects of tat have been postulated.
rev
rev – the second necessary regulatory factor for HIV expression. A 19 kD phosphoprotein localized primarily in the nucleolus/nucleus, rev acts by binding to RRE and promoting the nuclear export, stabilization and utilization of the viral mRNAs containing RRE.
vif
vif – viral infectivity factor, typically 23 kD; required for the efficient transmission of cell-free virus in tissue culture. In the absence of vif, the produced viral particles are defective, while the cell-to-cell transmission of virus is not affected significantly. It has been reported that the cellular localization is in the Golgi (vif is not found in the virion).
nef
nef – approximately 27 kD non-virion protein found in the cytoplasm of infected cells. Potentially myristoylated and associated with the inner plasma membrane. One of the first HIV proteins to be produced in the infected cells, it is the most immunogenic of the accessory proteins and may be used in the future for diagnosis and staging of the disease. NEF is dispensable and probably suffers counter-selection during ex vivo viral propagation in vivo. Recent evidence suggests that SIV nef is required for viral propagation in vivo.
vpr
vpr – virion-associated protein of unknown function found in HIV-1, HIV-2, SIVmac, and SIVmnd; typically 15 kD. May be homologous to vpx. Also called “rap” for rapid.
vpu
vpu – protein that promotes extracellular release of viral particles. Found only in HIV-1. Integral membrane phosphoprotein of 16kd; similar to M2 protein of influenza virus. It may be involved in env maturation. It is not found in the virion.
vpx
vpx – virion protein of 12 kD found only in HIV-2 infection. (vpx may have some homology with vpr).
Articles related to ESAT-6
The ESAT-6 Protein of Mycobacterium tuberculosis Interacts with Beta-2-Microglobulin (β2M) Affecting Antigen Presentation Function of Macrophage
ESAT-6, an abundantly secreted protein of Mycobacterium tuberculosis (M. tuberculosis) is an important virulence factor, inactivation of which leads to reduced virulence of M. tuberculosis. ESAT-6 alone, or in complex with its chaperone CFP-10 (ESAT-6:CFP-10), is known to modulate host immune responses; however, the detailed mechanisms are not well understood. The structure of ESAT-6 or ESAT-6:CFP-10 complex does not suggest presence of enzymatic or DNA-binding activities. Therefore, we hypothesized that the crucial role played by ESAT-6 in the virulence of mycobacteria could be due to its interaction with some host cellular factors. Using a yeast two-hybrid screening, we identified that ESAT-6 interacts with the host protein beta-2-microglobulin (β2M), which was further confirmed by other assays, like GST pull down, co-immunoprecipitation and surface plasmon resonance. The C-terminal six amino acid residues (90–95) of ESAT-6 were found to be essential for this interaction. ESAT-6, in complex with CFP-10, also interacts with β2M. We found that ESAT-6/ESAT-6:CFP-10 can enter into the endoplasmic reticulum where it sequesters β2M to inhibit cell surface expression of MHC-I-β2M complexes, resulting in downregulation of class I-mediated antigen presentation. Interestingly, the ESAT-6:β2M complex could be detected in pleural biopsies of individuals suffering from pleural tuberculosis. Our data highlight a novel mechanism by which M. tuberculosis may undermine the host adaptive immune responses to establish a successful infection. Identification of such novel interactions may help us in designing small molecule inhibitors as well as effective vaccine design against tuberculosis.
M. tuberculosis is a dangerous and highly successful pathogen that has evolved several mechanisms to manipulate the host immune regulatory network. Proteins secreted by M. tuberculosis play important roles in virulence. One such protein is ESAT-6, which is secreted along with its chaperone CFP-10. Despite a host of studies highlighting modulation of immune responses by ESAT-6, there have not been many that identified host proteins interacting with ESAT-6. We have now found that the host protein β2M interacts very specifically with ESAT-6 at its C-terminal region. The soluble ESAT-6:CFP-10 complex was found to be trafficked into the endoplasmic reticulum, and treatment with recombinant ESAT-6:CFP-10 or the over-expression of ESAT-6 reduced cell surface expression of β2M and molecules which remain associated with it like HLA-I. Recombinant ESAT-6:CFP-10 was also found to reduce classical and cross presentation of peptide antigens by MHC-I molecules. In summary, our data indicate that interaction between ESAT-6 and β2M can reduce the levels of available free β2M that associate with HLA/MHC-I molecules. This could be an interesting mechanism by which M. tuberculosis inhibits classical and cross presentation of peptide antigens in order to prevent or delay the onset of anti-mycobacterial adaptive immune responses.
ebiomall.com






>
>
>
>
>
>
>
>
>
>
>
>
1、存在于细胞外环境时,不显复制活性,但保持感染活性,是病毒体或病毒颗粒形式。
2、抗原,是指能够刺激机体产生(特异性)免疫应答,并能与免疫应答产物抗体和致敏淋巴细胞在体外结合,发生免疫效应(特异性反应)的物质
所以说,感染同一种病毒,每个人识别的表位可能不一样。
主要是中度以上细胞免疫缺陷包括:CD4+T淋巴细胞耗竭,外周血淋巴细胞显著减少,CD4<200/μl,CD4/CD8<1.0,(正常人为1.25~2.1),迟发型变态反应皮试阴性,有丝分裂原刺激反应低下。NK细胞活性下降。
2.各种致病性感染的病原体检查
如用PCR方法检测相关病原体,恶性肿瘤的组织病理学检查。
3.HIV抗体检测
采用酶联免疫吸附法、明胶颗粒凝集试验、免疫荧光检测法、免疫印迹检测法、放射免疫沉淀法等,其中前三项常用于筛选试验,后二者用于确证试验。
4.PCR技术检测HIV病毒。
核心抗原由183个或185个氨基酸组成,高度磷酸化,是乙肝病毒核心颗粒的唯一结构蛋白。正由于它存在于Dane颗粒核心结构表面,被表面抗原覆盖,故不易在血循环中检出。核心抗原具有强免疫原性,可诱导很强的体液免疫和细胞免疫,刺激机体产生抗-HBc。
e抗原为可溶性蛋白质,传染性强,游离存在于血液中,虽然很早就被发现,在病理上认为是HBV复制以具有强感染性的一个指标,但其功能尚不清楚。抗-HBe的出现,是预后良好的征象。向左转|向右转
流感病毒的基因组包含________基因,其中__________蛋白可作为__________的结构基础.
我不知道第一空如何填,第二空是否应该填"HA蛋白"?第3空是否应该填"突变"?
多谢各位啊!
新年快乐!
万事如意!
①乙型肝炎表面抗原—抗体系统(HBsAg/抗—HBs);
②乙型肝炎核心抗原—抗体系统(HBcAg/抗—HBc):
③乙型肝炎e抗原—抗体系统(HBeAg);
④乙型肝炎Dane颗粒抗原—抗体系统
⑤乙型肝炎δ抗原—抗体系统(δ/抗—δ)。
临床意义 1.HBsAg:血清中检测到HBsAg ,表示体内感染了HBV,因而是一种特异性标志。HBsAg阳性见于:①急性乙型肝炎的潜伏期或急性期(大多短期阳性);②HBV致的慢性肝病、迁延性和慢性活动性肝炎、肝炎后肝硬化或原发性肝癌等。③无症状携带者
2.抗HBs:表示曾感染过HBV,不论临床上有无肝炎症状表现,均已得到恢复,并且对HBV有一定的免疫力。
3.HBcAg与抗HBc:由于 HBcAg主要存在于肝细胞核内,并仅存在于Dane颗粒中。因此,对病人血清不能检测HBcAg,而测抗HBc。血清内抗HBc阳性反映:①新近有过HBV感染;②体内有HBV增殖;③有助于诊断急性或慢性乙型肝炎,特别是少数病例就诊时已处于急性恢复期早期,HBsAg已从血中消失,此时血中仅有抗HBc存在,因此,对恢复期患者可作病因追索。
4.HBcAg和抗HBe:HBcAg的存在常表示病人血液有感染性。 HBcAg阳性揭示病人肝脏可能有慢性损害,对预后判断有一定帮助。抗HBe阳性对病人可能有一定的保护力。展开

