CD21/CD35 Monoclonal Antibody (eBio4E3 (4E3)), APC, eBioscience™, Invitrogen™

Description

Description: The monoclonal antibody eBio4E3 reacts with an eptiope shared by mouse CD21 (CR2) and CD35 (CR1). CD21 and CD35 are alternatively spliced transcripts from the Cr2 gene, which result in cell-surface proteins of 145 and 190 kDa, respectively. CD21 and CD35 are expressed by mature B cells, but not on thymocytes, peripheral T cells, erythrocytes or platelets. Furthermore, there is little evidence which demonstrates their expression on macrophages. CD21 is a receptor for complement component C3d and Epstein-Barr virus (EBV), and in association with CD19 and CD81, CD21 also participates in B-cell activation through the B cell receptor. Cr2 deficient mice display impaired inflammatory and humoral immune responses in vivo. The anti-mouse CD21/35 monoclonal antibody clones eBio4E3 and eBio8D9 do not cross-block each other suggesting that they bind to different epitopes. Applications Reported: This eBio4E3 antibody has been reported for use in flow cytometric analysis. Applications Tested: This eBio4E3 antibody has been tested by flow cytometric analysis of mouse splenocytes. This may be used at less than or equal to 1.0 μg per test. A test is defined as the amount (μg) of antibody that will stain a cell sample in a final volume of 100 μL. Cell number should be determined empirically but can range from 10^5 to 10^8 cells/test. It is recommended that the antibody be carefully titrated for optimal performance in the assay of interest.

Excitation: 633-647 nm; Emission: 660 nm; Laser: Red Laser CD21 (complement receptor 2, CR2) binds C3 complement fragments, especially its breakdown fragments, which remain covalently attached to complement activating surfaces or antigen. CD21 has important roles in uptake and retention of immunocomplexes, survival of memory B cells and in development and maintece of the humoral response to T-dependent antigens. CD21 also serves as a key receptor for Epstein-Barr virus binding and is involved in targeting prions to folicular dendritic cells and expediting neuroinvasion following peripheral exposure to prions. A soluble form of the CD21 (sCD21) is shed from the lymphocyte surface and retains its ability to bind respective ligands. CD35 encodes a membrane glycoprotein found on peripheral blood cells, glomerular podocytes, and follicular dendritic cells. The protein is a receptor for complement components C3b and C4b and regulates the activity of the complement cascade. Variation in this protein is the basis of the Knops blood group system. The two most common alleles, F and S, differ by 8 exons and are thought to be the result of an unequal crossover event. A secreted form of the protein present in plasma has been described, but its full length nature has not been determined.