Complement receptor type 2 (CR2), also known as complement C3d receptor, Epstein–Barr virus receptor, and CD21 (cluster of differentiation 21), is a protein that in humans is encoded by the CR2 gene. CR2 is involved in the complement system. It binds to iC3b (inactive derivative of C3b), C3dg, or C3d. [5]

CRISPR-Cas9 deletion of CD21 on the Jurkat T-cell line confirmed that CD21 is required for EBV infection. This study has broad implications, as we have defined a function for CD21 on mature peripheral T cells, i.e., as a receptor for EBV.

CD21. Ⅱ 型补体受体、CR2、C3DR、补体 C3d 受体、Epstein-Barr 病毒受体. 成熟 B 细胞、滤泡树突细胞和 T 细胞亚群。 信号转导。补体成分 C3Dd 和 iC3b 以及 Epstein-Barr 病毒 (EBV) 糖蛋白 gp350/220 的受体。 CD22. SIGLEC2、BL-CAM、T 细胞表面抗原 Leu-14. 成熟 B 细胞。 B 细 …

2020年10月11日 · 在复合体中，cd21（即cr2）可结合c3d，形成cd21-c3d-抗原-bcr复合物，发挥b细胞共受体的作用；cd19传递活化信号。此外，cd21也是eb病毒受体，与eb病毒选择性感染b细胞有关。

2010年12月2日 · CD21表达于成熟B细胞和FDC，部分T细胞和鼻咽癌上皮细胞也有表达。 CD21的主要功能是： ①C3dg等补体片段往往与某些抗原分子结合而形成复合结构，该结构一端被BCR识别，另一端的补体成分被CD21识别，导致有关受体交联成簇，增强B细胞对抗原刺激的敏感性，并共同启动活化信号的胞内转导 (详后)。 实验显示，偶联有C3dg的鸡卵溶菌酶 (HEL)，其免疫原性比单纯HEI。 抗原分子提高1 000一10 000倍。 这是CD21的主要功能。 ②促进B细胞 …

Know comprehensive CD21 protein information including protein sequence, molecular weight, theoretical pI, structure, function and protein interaction.

2023年8月18日 · Forms a complex with CD19, CD81 and CD225 in the membrane of mature B cells; complex is often called the B cell coreceptor complex, because CD21 binds to antigens through attached C3d (or iC3b or C3dg) when the membrane IgM binds to the antigen, which results in a greatly enhanced response B cell response to the antigen

The complement receptor 2 (CR2, CD21) is part of a complex (CD21/CD19/CD81) acting as a co‐receptor to the B cell receptor (BCR). Simultaneous triggering of the BCR and CD21 lowers the threshold for B cell activation. Although CD21 is important, B ...

Complement receptors CD21 and CD35, which recognize activated products of C3 and C4, are predominantly expressed on B cells and follicular dendritic cells (FDCs) in the mouse. In this review, we focus on the role of FDC-expressed CD21 and CD35 in humoral immunity.

2007年3月1日 · The human CD21 is a receptor for cleavage fragments of the third complement component and for Epstein-Barr virus. Previous mutational studies showed that the cytoplasmic domain of CD21 is absolutely required for internalization of either ligand.