CD16 is a 50–80 kDa glycoprotein that is expressed in two different isoforms. The transmembrane form is found on human NK cells, macrophages, and mast cells, while the glycosylphosphatidylinositol (GPI)-linked form is present on neutrophils.
The human CD16 antigen is a low-affinity receptor for aggregated IgG. The transmembrane form plays a role in signal transduction, NK cell activation, and antibody-dependent cellular cytotoxicity. Clone VEP13 recognizes both the extracellular domain of the transmembrane form as well as the GPI-linked form of the human CD16 antigen. CD16 is expressed on the majority of rhesus monkey NK cells and on a subset of monocytes but not on granulocytes.
