CD21/CD35 Monoclonal Antibody (eBio8D9 (8D9)), eBioscience™, Invitrogen™

Description

• The MAb eBio8D9 reacts with an eptiope shared by mouse CD21 (CR2) and CD35 (CR1)
• CD21 and CD35 are alternatively spliced transcripts from the Cr2 gene, which produce 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 some evidence which demonstrates their expression on macrophages
• CD21 is a receptor for the complement component C3d and Epstein-Barr virus (EBV)
• 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 MAb clones eBio4E3 and eBio8D9 do not cross-block each other, suggesting that they bind to different epitopes
• 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 maintenance 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.