Cluster Of Differentiation 64 (CD64)

CD64 is a type of integral membrane glycoprotein known as an Fc receptor that binds monomeric IgG-type antibodies with high affinity. It is more commonly known as Fc-gamma receptor 1 (Fc gamma RI). After binding IgG, CD64 interacts with an accessory chain known as the common gamma chain (gamma chain), which possesses an ITAM motif that is necessary for triggering cellular activation.Structurally CD64 is composed of a signal peptide that allows its transport to the surface of a cell, three extracellular immunoglobulin domains of the C2-type that it uses to bind antibody, a hydrophobic transmembrane domain, and a short cytoplasmic tail.CD64 is constitutively found on only macrophages and monocytes, but treatment of polymorphonuclear leukocytes with cytokines like IFN gamma; and G-CSF can induce CD64 expression on these cells.