anti-LILRB4 monoclonal antibody MK-0482

A humanized immunoglobulin G4 (IgG4) monoclonal antibody directed against the myeloid-enriched immune inhibitory receptor leukocyte immunoglobulin-like receptor B member 4 (LILRB4; ILT3; ILT-3), with potential immune checkpoint inhibitory and antineoplastic activities. Upon administration, anti-LILRB4 monoclonal antibody MK-0482 targets, binds to and blocks LILRB4, thereby preventing the interaction with its ligands, such as fibronectin, in the tumor microenvironment (TME). This prevents the activation of LILRB4-mediated downstream signaling pathways. This may abrogate LILRB4-mediated promotion of myeloid cell immunosuppression and inhibition of antitumor immunity. This may restore immune function by activating dendritic cells (DCs) and T-cells, and may promote T-cell-mediated immune responses against tumor cells. LILRB4, an inhibitory immune receptor highly expressed on tumor-associated myeloid cells, primarily tolerogenic DCs, myeloid-derived suppressor cells (MDSCs) and M2 macrophages, functions as an immune checkpoint that negatively regulates DC- and T-cell activation. It is upregulated in several tumor types and plays an important role in tumor infiltration, immunosuppression and immune tolerance.