Leukocyte immunoglobulin-like receptor subfamily A member 2 (LILRA2)

Leukocyte immunoglobulin-like receptor subfamily A member 2 (LILRA2) is an activating immune receptor mainly expressed on monocytes and B cells, and at lower levels on dendritic cells and natural killer cells. It belongs to the immunoglobulin superfamily and is part of the broader leukocyte immunoglobulin-like receptor (LILR) gene cluster. Unlike inhibitory LILRB receptors, LILRA2 possesses a short cytoplasmic tail lacking immunoreceptor tyrosine-based inhibitory motifs (ITIMs), and instead mediates activating signals through association with the FcRγ chain. LILRA2 recognizes endogenous ligands—in particular, it binds to solid-phase fibrinogen (not soluble fibrinogen or fibrin), thereby activating monocytes and promoting the expression of inflammation-related genes. It also senses microbially cleaved immunoglobulin as a danger-associated molecular pattern, linking microbial infection to immune activation. LILRA2 does not bind HLA class I molecules, distinguishing it from other LILRs. Elevated LILRA2 expression and functional polymorphisms are implicated in autoimmune conditions (including SLE and microscopic polyangiitis), leprosy, and inflammatory diseases, making it a potential immunological biomarker and therapeutic target for diseases characterized by inappropriate or excessive immune activation[1][2][3][4].

Other names

CD85hILT1LIR7Leukocyte Ig-like receptor A2Immunoglobulin-like transcript 1CD85 antigen-like family member HLIR-7