Description: The WM-15 monoclonal antibody reacts with human CD13, also known as aminopeptidase N. CD13 is a transmembrane ectoenzyme occurring on monocytes and granulocytes but not lymphocytes in blood. It is also reportedly on a wide variety of cells and in a wide variety of tissues, including endothelial cells, epithelial cells, fibroblasts, kidney proximal tubules, intestine, and placenta. CD13 is reported to have many different functions including degradation of enkephalins and endorphins, terminal degradation of peptides, amino acid scavenging, antigen processing, and adhesion and migration of cells.