CR2 and CD21, is a protein involved in the complement system.
It binds to iC3b (inactive derivative of C3b), C3dg, or C3d.
B cells have CR2 receptors on their surfaces, allowing the complement system to play a role in B-cell activation and maturation.CR2 on mature B cells form a complex with two other membrane proteins, CD19 and CD81(=TAPA-1).
The CR2-CD19-CD81 complex is often called the B cell coreceptor complex, because CR2 binds to antigens through attached C3d (or iC3b or C3dg) when the menbrane IgM binds to the antigen.
This results in the B cell to have greatly enhanced response to the antigen.
Epstein-Barr virus (EBV) binds to B cells at CR2 during infection of these cells.
Yefenof et al.
(1976) found complete overlapping of EBV receptors and C3 receptors on human B lymphocytes.
Applications:Suitable for use in ELISA, Western Blot, Immunohistochemistry, Immunocytochemistry.
Other applications not tested.
Recommended Dilution:ELISA: 1:100-1:5000Western Blot: 1:50-400Immunocytochemistry: 1:50-500Immunohistochemistry (frozen): 1:50-500Immunohistochemistry (paraffin): 1:10-100Optimal dilutions to be determined by the researcher.