LILRA4 also known as ILT7 and CD85g is an approximately 60-70 kDa variably glycosylated transmembrane protein that regulates immune cell activation Mature human LILRA4 consists of a 423 amino acid (aa) extracellular domain (ECD) with four immunoglobulin-like domains a 21 aa transmembrane segment and a 32 aa cytoplasmic domain LILRA4 function coreceptor to limit the innate immune responses to viral infections signaling occurs via FCER1G (PubMed 16735691 PubMed 19564354) Down-regulates the production of IFNA1 IFNA2 IFNA4 IFNB1 and TNF by plasmacytoid dendritic cells that have been exposed to influenza virus or cytidine-phosphate-guanosine (CpG) dinucleotides indicating it functions as negative regulator of TLR7 and TLR9 signaling cascades