Enterotoxin type B 蛋白, S. aureus (P.pastoris, His)

Enterotoxin B (SEB) is an antigen derived from Staphylococcus aureus (S. aureus) that can be recognized and bound by MHC class II molecules on antigen-presenting cells. Enterotoxin B also interacts with T cell receptors (TCRs), triggering massive activation of CD4+ and CD8+ T cells, leading to the release of proinflammatory cytokines (TNF-α, IFN-γ) and Th2-type cytokines (IL-4, IL-5, IL-13), regulating inflammatory responses. Enterotoxin B also exerts anti-tumor potential in fibrosarcoma models, inducing tumor necrosis. Enterotoxin type B Protein, S. aureus (P.pastoris, His) is a recombinant Enterotoxin B protein expressed by P. pastoris yeast with N-6*His tag.

Enterotoxin type B, S. aureus 是金黄色葡萄球菌 (S. aureus) 来源的 Enterotoxin B (SEB) 超级抗原，属于葡萄球菌肠毒素家族。Enterotoxin B 的结构上与抗原呈递细胞上的 MHC II 类分子结合，并与 T 细胞受体 (TCR) β 链的可变区结合，激活表达特定 (Vβ)-TCR 片段的 T 细胞。Enterotoxin B-TCR，可触发 CD4+ 和 CD8+ T 细胞的大量活化，导致促炎细胞因子 (TNF-α、IFN-γ) 和 Th2 型细胞因子 (IL-4、IL-5、IL-13) 的释放，并通过 TNF 和 IFN-γ 介导一氧化氮 (NO) 的合成。Enterotoxin B 的活性涉及一个调节环路，其中 NO 下调细胞因子产生以防止过度炎症。Enterotoxin B 已被证实鼻息肉模型中诱导 T_H2 偏向的细胞因子释放；在内毒素休克模型中，观察到 NO 介导的抗致死性细胞因子风暴的保护作用。此外，静脉注射 Enterotoxin B 可增强 IFN-γ 产生和 CD4+/CD8+ T 细胞浸润，在纤维肉瘤模型中显示出抗肿瘤潜力，诱导肿瘤坏死。

Enterotoxin type B Protein, S. aureus (100 μg；腹腔注射；1 次；单次) 可诱导小鼠内毒素休克模型大量合成 NO。NO 的合成受 TNF 和 IFN-γ 调控，同时，内源性 NO 可下调 TNF 和 IFN-γ 的产生而发挥保护作用。抑制 NO 合成将导致小鼠死亡，中和 IFN-γ 和 TNF 则能够降低小鼠的死亡率^[1]。
Enterotoxin type B Protein, S. aureus (10 ng；静脉注射；每 3 天 1次；2 周) 可显著抑制小鼠纤维肉瘤模型的肿瘤生长，提高 IFN-γ 水平及 CD4+/CD8+ T 细胞浸润率，诱导肿瘤组织坏死，而瘤内注射无明显抑瘤效果^[2]。

Measured by its ability to induce IL-10 secretion by Raji cells. The ED₅₀ for this effect is 53.25 ng/mL, corresponding to a specific activity is 1.878×10^4 U/mg.

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  Measured by its ability to induce IL-10 secretion by Raji cells. The ED₅₀ for this effect is 53.25 ng/mL, corresponding to a specific activity is 1.878×10^4 U/mg.

Staphylococcus aureus

P. pastoris

N-6*His

P01552 (E28-K266)

/

Full Length of Mature Protein

ESQPDPKPDELHKSSKFTGLMENMKVLYDDNHVSAINVKSIDQFLYFDLIYSIKDTKLGNYDNVRVEFKNKDLADKYKDKYVDVFGANYYYQCYFSKKTNDINSHQTDKRKTCMYGGVTEHNGNQLDKYRSITVRVFEDGKNLLSFDVQTNKKKVTAQELDYLTRHYLVKNKKLYEFNNSPYETGYIKFIENENSFWYDMMPAPGDKFDQSKYLMMYNDNKMVDSKDVKIEVYLTTKKK

Approximately 30.4 kDa

Greater than 90% as determined by reducing SDS-PAGE.

无菌粉末

Lyophilized from a 0.22 μm filtered solution of 20 mM Tris-HC1, 0.5 M NaCl, 6% Trehalose, pH 8.0 or PBS, 6% Trehalose, pH 7.4.
Note: For SPR assay, please replace the buffer. Primary amine components (e.g., Tris, imidazole) can affect protein-coupled chips.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O.

Stored at -20°C for 2 years from date of receipt. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.

• [1]. Patou J, et al. Staphylococcus aureus enterotoxin B, protein A, and lipoteichoic acid stimulations in nasal polyps. J Allergy Clin Immunol. 2008 Jan;121(1):110-5.  [Content Brief]

  [2]. Heidari M, et al. Staphylococcus aureus enterotoxin type B (SEB) and alpha-toxin induced apoptosis in KB cell line[J]. Journal of Medical Microbiology and Infectious Diseases, 2023, 11(2): 96-102.

  [3]. Florquin S, et al. The protective role of endogenously synthesized nitric oxide in staphylococcal enterotoxin B-induced shock in mice. J Exp Med. 1994 Sep 1;180(3):1153-8.  [Content Brief]

  [4]. Fooladi AA, et al. In vivo induction of necrosis in mice fibrosarcoma via intravenous injection of type B staphylococcal enterotoxin. Biotechnol Lett. 2008 Dec;30(12):2053-9.  [Content Brief]