PE-Labeled Human CD19 (20-291) Protein, His Tag

分子別名（Synonym）

CD19, B4, CVID3, MGC12802

表達(dá)區(qū)間及表達(dá)系統(tǒng)（Source）

PE-Labeled Human CD19 (20-291), His Tag (CD9-HP2H5) is produced via conjugation of PE to Human CD19 (20-291), His Tag with a new generation site-specific technology under Star Staining labeling platform. Human CD19 (20-291), His Tag is expressed from human 293 cells (HEK293). It contains AA Pro 20 - Lys 291 (Accession # P15391-1).

蛋白結(jié)構(gòu)（Molecular Characterization）

This protein carries a polyhistidine tag at the C-terminus.

偶聯(lián)（Conjugate）

PE

Excitation Wavelength: 488 nm / 561 nm

Emission Wavelength: 575 nm

制劑（Formulation）

Lyophilized from 0.22 μm filtered solution in PBS, 0.2% BSA, pH7.4 with trehalose as protectant.

Contact us for customized product form or formulation.

重構(gòu)方法（Reconstitution）

Please see Certificate of Analysis for specific instructions.

For best performance, we strongly recommend you to follow the reconstitution protocol provided in the CoA.

存儲（Storage）

For long term storage, the product should be stored at lyophilized state at -20°C or lower.

Please protect from light and avoid repeated freeze-thaw cycles.

This product is stable after storage at:

-20°C to -70°C for 12 months in lyophilized state;

-70°C for 3 months under sterile conditions after reconstitution.

背景介紹

B淋巴細(xì)胞抗原CD19（亦稱CD19或分化簇19）是一種單次跨膜I型膜蛋白，包含兩個免疫球蛋白樣C2型結(jié)構(gòu)域。該蛋白表達(dá)于濾泡樹突細(xì)胞及B細(xì)胞表面——事實上，從發(fā)育過程中最早可識別的B系細(xì)胞到B母細(xì)胞階段持續(xù)存在，但在成熟為漿細(xì)胞時消失。CD19主要作為B細(xì)胞共受體，與CD21及CD81協(xié)同作用。激活狀態(tài)下，其胞質(zhì)尾區(qū)發(fā)生磷酸化，進(jìn)而招募Src家族激酶及PI-3激酶。

與T細(xì)胞類似，B淋巴細(xì)胞表面多個分子共同構(gòu)成抗原受體復(fù)合物。CD19（幾乎為B細(xì)胞特異性表達(dá)的磷酸化糖蛋白）即為關(guān)鍵組分，其他成員包括CD21與CD81。這些表面免疫球蛋白（sIg）關(guān)聯(lián)分子協(xié)同介導(dǎo)信號轉(zhuǎn)導(dǎo)：活體B細(xì)胞中，模擬外源抗原的抗免疫球蛋白抗體會引發(fā)CD19與sIg結(jié)合并隨之內(nèi)化，而逆向過程尚未證實，表明該受體復(fù)合物的形成由抗原誘導(dǎo)（此分子互作機制已獲化學(xué)研究證實）。

CD19基因突變可導(dǎo)致以抗體生成減少為特征的重度免疫缺陷綜合征。經(jīng)證實，CD19可與下列分子相互作用：CD81、CD82、補體受體2及VAV2。