人CD20蛋白(VLP)

Human CD20 Full Length Protein (VLP)

分子别名（Synonym）

MS4A1, CD20, MS4A-1

表达区间及表达系统（Source）

Human CD20 Full Length Protein-VLP (CDP-H52P6) is expressed from human 293 cells (HEK293). It contains AA Met 1 - Pro 297 (Accession # P11836-1).

Predicted N-terminus: Met

蛋白结构（Molecular Characterization）

Virus-like particles(VLPs) are formed by self-assembly of capsid proteins from viruses. Membrane Proteins can be constituted in-situ with VLPs produced from HEK293 cell cultures. These VLPs concentrate conformationally intact membrane proteins directly on the cell surface and produce soluble, high-concentration proteins perfect for immunization and antibody screening.

The VLPs provide the display of properly folded membrane proteins in their native cellular membrane in a compact size of 100~300 nm diameter (similar to the size of most viruses) making it optimal targets for dendritic cells in vivo and surface attachment for phage display.

内毒素（Endotoxin）

Less than 1.0 EU per μg by the LAL method / rFC method.

纯度（Purity）

>95% as determined by SEC-HPLC.

制剂（Formulation）

The VLPs are highly immunogenic, so the immunization strategy should be optimized (antigen dose, regimen and adjuvant).

Supplied as 0.2 μm filtered solution in PBS, pH7.4 with trehalose as protectant.

Contact us for customized product form or formulation.

运输（Shipping）

This product is supplied and shipped with dry ice, please inquire the shipping cost.

存储（Storage）

Please avoid repeated freeze-thaw cycles.

This product is stable after storage at:

The product MUST be stored at -70°C or lower upon receipt;

-70°C for 12 months under sterile conditions.

背景介绍

B淋巴细胞抗原CD20（亦称B淋巴细胞表面抗原B1、白细胞表面抗原Leu-16、四次跨膜结构域亚家族A成员1、MS4A1）是一种活化糖基化磷蛋白。该抗原从祖B细胞阶段（CD45R+、CD117+）开始表达于所有B细胞表面，其浓度随细胞成熟度逐步增加。CD20在B细胞发育除最初和最终阶段外的所有时期均有表达——从晚期祖B细胞到记忆B细胞均存在，但早期祖B细胞、浆母细胞及浆细胞中不表达。

该抗原常见于B细胞淋巴瘤、毛细胞白血病、B细胞慢性淋巴细胞白血病和黑色素瘤癌症干细胞表面。其功能虽无已知天然配体，但能介导最佳B细胞免疫应答（尤其针对T细胞非依赖性抗原），推测其可能作为钙通道存在于细胞膜上。

CD20/MS4A1是单克隆抗体利妥昔单抗、替伊莫单抗和托西莫单靶向治疗的靶点，这些抗体药物对所有B细胞淋巴瘤和白血病均有治疗活性。CD20/MS4A1缺陷会导致5型常见变异型免疫缺陷病（CVID5，又称CD20缺陷性抗体缺乏症）。该疾病是一种以抗体缺陷、低丙种球蛋白血症、反复细菌感染及抗原抗体应答无能为主要特征的原发性免疫缺陷病。