ErbB-2 (CD340) Antibody, anti-

Identification and enumeration of ErbB-2+ cells by flow cytometryClone 24D2 recognizes the human receptor tyrosine-protein kinase ErbB-2 antigen, a single-pass type I membrane protein which is also known as CD340, human epidermal growth factor receptor 2 (Her2), or proto-oncogene Neu. ErbB-2 is a member of the epidermal growth factor receptor family. The ErbB family is composed of four plasma membrane-bound receptor tyrosine kinases. All four contain an extracellular ligand binding domain, a transmembrane domain, and an intracellular domain that can interact with a multitude of signaling molecules and exhibit both ligand-dependent and ligand-independent activity. ErbB-2 can heterodimerise with any of the other three receptors and is considered to be the preferred dimerisation partner of the other ErbB receptors. Dimerisation results in the autophosphorylation of tyrosine residues within the cytoplasmic domain of the receptors and initiates a variety of signaling pathways. ErbB-2 has been shown to be involved in embryonic development and cancer progression. Amplification or overexpression of this oncogene has been shown to play an important role in the development and progression of certain aggressive types of cancer. In recent years the protein has become an important biomarker.