B220 Antibodies

Structure of B220

B220 (CD45) is a large type I transmembrane protein with a molecular weight of approximately 180-220 kDa. The specific molecular weight varies depending on the splicing isomer. This value is highly conserved in different species and is mainly contributed by the highly glycosylated domain of the extracellular segment.

The B220 protein is composed of an extracellular region, a transmembrane region and an intracellular region. Its extracellular region contains multiple fibronectin type III domains and a large number of glycosylation modifications (the name "B220" is derived from the electrophoretic mobility caused by its glycosylation characteristics), which endows it with its unique antigenicity. The intracellular region has two tyrosine phosphatase domains (D1 and D2) with catalytic activity. Among them, the D1 domain is the functional core. By dephosphorylating the key regulatory sites of Src family kinases, it directly participates in the activation or inhibition of T cell and B cell receptor signals, thereby precisely regulating the immune response of lymphocytes.

Fig. 1 Role of B220+CD11c+NK1.1+ HepELs in metastasis.¹

Key structural properties of B220:

• Large type I transmembrane glycoproteins with multiple alternative splicing extracellular domains
• Extracellular region rich in cysteine and have a large number of glycosylation modification
• Intracellular area contains two series of tyrosine phosphatase domain structure (D1 and D2)

Functions of B220

The main function of B220 (CD45) is to act as a key regulatory molecule in lymphocyte signal transduction. However, it also extensively involves multiple aspects of the immune response, including cell activation, developmental differentiation, and immune tolerance.

B220 has a high degree of specificity in signal regulation for different lymphocyte subsets, and its function depends on the cell type, developmental stage and the form of the isomer spliced. This complexity makes it a precise "regulatory hub" of the immune system.

Applications of B220 and B220 Antibody in Literature

1. Hiratsuka, Sachie, et al. "Hepato‐entrained B220+ CD 11c+ NK 1.1+ cells regulate pre‐metastatic niche formation in the lung." EMBO molecular medicine 10.7 (2018): e8643. https://doi.org/10.15252/emmm.201708643

The article indicates that the liver inhibits the formation of lung metastases by releasing B220+ CD11c+ NK1.1+ cells. This type of cells highly express coagulation factor X, which can clear fibrin deposits in lung tissue and exert anti-tumor effects by inducing IFNγ.

2. Vacani-Martins, Natalia, et al. "After Experimental Trypanosoma cruzi Infection, Dying Hepatic CD3+ TCRαβ+ B220+ T Lymphocytes Are Rescued from Death by Peripheral T Cells and Become Activated." Pathogens 9.9 (2020): 717. https://doi.org/10.3390/pathogens9090717

This study explored the role of liver CD3+B220+ T cells in Trypanosoma cruzii infection. It was found that this type of cells contained CD117− apoptotic subsets and CD117+ thymus-independent subsets, and the majority were 7AAD+ apoptotic cells. After infection, approximately 15% of the CD117+ population transformed into B220−7AAD−, expressing CD90.2 and activation markers, and was rescued and survived by peripheral activated T cells, indicating its potential for activation and immune regulation.

3. Benbijja, Mohcine, Amine Mellouk, and Pierre Bobé. "Sensitivity of leukemic T-cell lines to arsenic trioxide cytotoxicity is dependent on the induction of phosphatase B220/CD45R expression at the cell surface." Molecular cancer 13.1 (2014): 251. https://doi.org/10.1186/1476-4598-13-251

Research has found that the sensitivity of leukemia T cells to arsenic trioxide (As₂O₃) is closely related to the expression level of B220 (CD45 isomer). Treatment with As₂O₃ can dose-dependently induce membrane expression of B220 and inhibit nuclear translocation of NF-κB p50, thereby inducing apoptosis or mixed cell death. The expression level of B220 is strictly related to the degree and form of cell death, suggesting that it may serve as a key regulatory factor in the death pathway.

4. Wilson, Kyle A., et al. "Depletion of B220+ NK1. 1+ cells enhances the rejection of established melanoma by tumor-specific CD4+ T cells." Oncoimmunology 4.8 (2015): e1019196. https://doi.org/10.1080/2162402X.2015.1019196

This study found that in adoptive T-cell therapy (ACT) for melanoma, eliminating NK1.1+ cells can enhance the anti-tumor effect of CD4+ T cells. Among them, NK1.1+B220+ pre-mNK cells (i.e., IKDC) are the key population that inhibits the anti-tumor immune response. Targeting this group can increase the number of T cells, levels of inflammatory factors and survival rates, providing a new strategy for improving the efficacy of ACT.

5. Le Gall, Sylvain M., et al. "Loss of P2X7 receptor plasma membrane expression and function in pathogenic B220+ double-negative T lymphocytes of autoimmune MRL/lpr mice." PLoS One 7.12 (2012): e52161. https://doi.org/10.1371/journal.pone.0052161

In lupus model MRL/lpr mice, B220+ CD4-CD8-T cells accumulate abnormally. Research has found that although the B220+ T cell subset expresses the P2X7 receptor intracellularly, the P2X7R is absent on the membrane surface, resulting in no response to ATP/NAD stimulation and apoptotic signals. The surface expression of B220 is significantly correlated with the inhibition of the P2X7R pathway, suggesting its involvement in regulating abnormal T cell survival and autoimmunity.

Creative Biolabs: B220 Antibodies for Research

Creative Biolabs specializes in the production of high-quality B220 antibodies for research and industrial applications. Our portfolio includes monoclonal antibodies tailored for ELISA, Flow Cytometry, Western blot, immunohistochemistry, and other diagnostic methodologies.

• Custom B220 Antibody Development: Tailor-made solutions to meet specific research requirements.
• Bulk Production: Large-scale antibody manufacturing for industry partners.
• Technical Support: Expert consultation for protocol optimization and troubleshooting.
• Aliquoting Services: Conveniently sized aliquots for long-term storage and consistent experimental outcomes.

For more details on our B220 antibodies, custom preparations, or technical support, contact us at email.