CD85 is a group of Ig superfamily tansmembrane glycoproteins called Ig-Like Transcripts (ILTs) or Leukocyte Immunoglobulin-like Receptors (LIRs). It is composed of both activating and inhibitory isoforms. The activating subset of ILTs is characterized by containing short cytoplasmic domains and positively charged arginine residues, while the inhibitory isoforms display long cytoplasmic tails containing ITIM motifs. CD85d is a 95kD inhibitory receptor, also known as ILT4, LIR2, or MIR10. ILT4 is expressed on the surface of monocytes/macrophages, and dendritic cells. ILT4 acts as an inhibitory receptor through recruitment of SHP-1 and SHP-2 protein tyrosine phosphatases. The ligands of ILT4 are HLA-A, -B and nonclassical MHC-I molecule HLA-G1.