Recombinant Mouse Monoclonal Antibody to CD21

CD21 is a 145 kD transmembrane protein also known as complement C3d receptor (C3dR), complement receptor 2 (CR2), and Epstein-Barr virus receptor. CD21 is expressed on B cells, follicular dendritic cells, subsets of normal thymocytes and T cells, and some epithelial cells. CD21 is the receptor used by Epstein-Barr virus to infect B cells and is also the complement receptor for C3d. CD21 has also been shown to interact with a number of proteins, including CD23, CD19, annexin VI, CD81, iC3b, complement receptor 1 (CR1, CD35), and interferon-alpha 1 (IFN-α1).