The monoclonal antibody HM47 reacts with the cytoplamic domain of CD79a, which is also known as mb-1 and Ig α. Along with CD79b (Ig β), CD79a is associated with surface Ig (sIg) to form the B cell antigen receptor complex. CD79a is a 47 kDa glycoprotein and comprises a single extracellular immunoglobulin domain, a transmembrane domain, and a signaling intracellular domain with immunoreceptor tyrosine-based activation motif (ITAM). CD79a/CD79b heterodimer facilitates differentiation of pre–B cells from pro–B cells, surface expression of sIg, signal transduction following antigen recognition and enodocytosis of recognised antigens. Surface expression of CD79a dimishes in plasma cells, where it is mainly found as an intracellular molecule. CD79 is considered a B cell–specific marker and is often used to identify the B cell lineage of acute lymphoblastic leukemia. Recent reports however suggest expression of CD79a in T cell acute lymphoblastic leukemia. Individuals lacking CD79a have low/absent circulating pre–B cells and serum antibodies due to a block in B cell development.
Igα, MB-1
Technical specifications
