CD19 蛋白, Human (HEK293, His)

The CD19 protein is a B cell antigen receptor coreceptor that enhances downstream signaling pathways, lowers the activation threshold, and helps B cells respond to antigens. It activates phosphatidylinositol 3-kinase and mobilizes intracellular Ca(2+). CD19 Protein, Human (HEK293, His) is the recombinant human-derived CD19 protein, expressed by HEK293 , with C-His labeled tag. The total length of CD19 Protein, Human (HEK293, His) is 291 a.a., with molecular weight of ~47 kDa.

CD19 蛋白作为 B 淋巴细胞上 B 细胞抗原受体复合物 (BCR) 的共受体，在降低下游信号通路激活阈值和促进 B 细胞对抗原的反应方面发挥着关键作用。它激活信号通路，导致磷脂酰肌醇 3-激酶的激活和细胞内 Ca(2+) 储备的动员。尽管 CD19 不是骨髓中 B 细胞分化早期步骤所必需的，但它对于 B-1 细胞的正常分化至关重要。此外，它对于正常 B 细胞响应抗原挑战的分化和增殖至关重要，影响血清免疫球蛋白水平和响应抗原挑战的高亲和力抗体的产生。CD19 与成熟 B 细胞膜上的 CR2/CD21、CD81 和 IFITM1/CD225 形成复合物。它直接与 CD81 相互作用，这是活化 B 细胞表面 CD19 受体运输和区室化的关键相互作用。此外，当在特定酪氨酸残基上磷酸化时，CD19 与 VAV、GRB2、SOS、PLCG2、LYN 和磷脂酰肌醇 3-激酶的调节 p85 亚基相互作用。

Immobilized human CD19-His at 2 μg/mL (100 μL/well) can bind Anti-CD19 Antibody and the EC₅₀ is 5-40 ng/mL.

Human

HEK293

C-His

P15391-1 (M1-K291)

930  [NCBI]

Approximately 47 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. Normally 5 % - 8 % trehalose, mannitol and 0.01% Tween 80 are added as protectants before lyophilization.

<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. 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.