CD81 蛋白, Human (HEK293, His)

The CD19 receptor is critical for B cell activation, driving the trafficking and assembly of CD19-CR2 and BCR complexes, thereby lowering the antigenic threshold for B cell clonal expansion. In T cells, CD19 contributes to CD3 localization and influences polarization. CD81 Protein, Human (HEK293, His) is the recombinant human-derived CD81 protein, expressed by HEK293 , with N-His labeled tag. The total length of CD81 Protein, Human (HEK293, His) is 89 a.a., with molecular weight of 10-13 kDa.

CD19 受体在活化 B 细胞的运输和区室化中发挥着至关重要的作用。它允许 CD19-CR2/CD21 和 B 细胞受体 (BCR) 复合物在信号传导 TERM 处组装，从而导致触发 B 细胞克隆扩增和抗体产生所需的抗原阈值剂量较低。该受体还促进 CD247/CD3 zeta 与 T 细胞中的 B 细胞在抗原诱导的突触处的定位，提供向 2 型辅助 T 表型的共刺激和极化。此外，CD19 存在于 MHC II 类区室中，可能在抗原呈递中发挥作用。它可以充当细胞-细胞融合过程的正调节剂和负调节剂。CD19正向调节精卵融合并可能参与顶体反应。在成肌细胞中，它与 CD9 和 PTGFRN 结合，抑制肌肉再生过程中的肌管融合。在巨噬细胞中，CD19 与 CD9 以及 beta-1 和 beta-2 整合素结合，以防止巨噬细胞融合成专门摄取补体调理的大颗粒的多核巨细胞。它还可以防止单核细胞祖细胞融合成负责骨吸收的破骨细胞。CD19 还可以调节酶活性的区室化。在 T 细胞中，它定义 dNTPase SAMHD1 的亚细胞定位，并允许其被蛋白酶体降解，从而控制细胞内 dNTP 水平。CD19 还参与细胞粘附和运动，积极调节整合素介导的巨噬细胞粘附，特别是在肺部炎症反应中。此外，CD19 在肝细胞中充当丙型肝炎病毒 (HCV) 的受体，与 CLDN1 和 CLDN1-CD81 受体复合物结合，对于 HCV 进入宿主细胞至关重要。

Immobilized Human CD81 at 1 μg/mL (100 μL/well) can bind Anti-CD81 Antibody, The ED₅₀ is 31.58 ng/mL, corresponding to a specific activity is 3.17×10⁴ U/mg.

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  Immobilized Human CD81 at 1 μg/mL (100 μL/well) can bind Anti-CD81 Antibody,  The ED₅₀ for this effect is 31.58 ng/mL，corresponding to a specific activity is 3.17×10⁴ U/mg.

Human

HEK293

N-His

P60033 (F113-K201)

975  [NCBI]

FVNKDQIAKDVKQFYDQALQQAVVDDDANNAKAVVKTFHETLDCCGSSTLTALTTSVLKNNLCPSGSNIISNLFKEDCHQKIDDLFSGK

10-13 kDa

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

无菌粉末.

Lyophilized from a 0.2 μm filtered solution of PBS, pH 7.4.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O. For long term storage it is recommended to add a carrier protein (0.1% BSA, 5% HSA, 10% FBS or 5% Trehalose).

Stored at -20°C for 2 years. 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.