Clone REA513 recognizes the human CD81 antigen, a multi-pass membrane protein also known as TAPA-1. It is a member of the tetraspanin family including, for example, CD9, CD37, CD53, CD63, CD82, and CD151. The proteins mediate signal transduction events that play a role in the regulation of cell development, activation, growth, and motility. The 26 kDa cell surface protein is involved in adhesion, activation, proliferation, and differentiation of B cells, T cells, and other cells. On B cells CD81 is part of a complex with CD21, CD19, and Leu13. Similarly on T cells CD81 associates with CD4 and CD8 and provides a costimulatory signal with CD3. CD81 is expressed by epithelial and endothelial cells, T and B cells, as well as natural killer (NK) cells.
Additional information: Clone REA513 displays negligible binding to Fc receptors.