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