The Ber-H2 monoclonal antibody specifically reacts with human CD30, a 120kDA type I transmembrane glycoprotein of the tumor necrosis factor receptor superfamily (TNFR) also known as the Ki-1 antigen. CD30 can elicit signals leading to either activation or apoptosis through interaction with CD30 ligand (CD30L). It is expressed by a subset of extrafollicular activated B and T cells, lung macrophages, activated NK cells, lymphomas, and endothelial cells. It is highly expressed on Hodgkins and Reed-Sternberg cells.