LILRB2, also known as Leukocyte Immunoglobulin-Like Receptor Subfamily B Member 2, CD85 antigen-related family member D (CD85d), Immunoglobulin-Like Transcript 4 (ILT-4), and Monocyte/Macrophage Immunoglobulin-Like Receptor 10 (MIR-10).
LILRB2 is a surface receptor on bone marrow cells, comprising four extracellular immunoglobulin domains, a transmembrane domain, and three cytoplasmic immunoreceptor tyrosine-based inhibitory motifs (ITIM). LILRB2 interacts with bone marrow cells through its endogenous ligands (classic MHC I molecules [e.g., HLA-A, HLA-B] and non-classic MHC I molecules [e.g., HLA-G]), providing negative signaling to inhibit immune response stimulation.
HLA-G is considered an important immune inhibitory molecule, playing a role in maternal-fetal tolerance and often overexpressed in cancer, typically associated with late-stage disease and poor prognosis. Given that tumor-associated macrophages are known to suppress anti-cancer immune responses, these findings provide a theoretical basis for targeting LILRB2.
