Used in immunotherapy research targeting immune checkpoint pathways. Binds specifically to LILRB4 (ILT3/CD85k), a receptor expressed on myeloid-derived suppressor cells and certain antigen-presenting cells. This interaction modulates T-cell suppression, making it valuable for studying tumor immune evasion mechanisms. Investigated for potential in enhancing anti-tumor immune responses, particularly in acute myeloid leukemia and solid tumors. Also employed as a tool in flow cytometry, immunohistochemistry, and functional assays to characterize immune cell populations and evaluate therapeutic targeting strategies.