Used in immunotherapy research and development, particularly in targeting immune checkpoint pathways. It binds to PSGL-1 (P-selectin glycoprotein ligand-1), a protein involved in leukocyte trafficking and immune cell interactions. By blocking PSGL-1, the antibody enhances T cell activation and infiltration into tumors, supporting anti-tumor immune responses. Investigated for use in cancer treatment, especially in combination with other immunotherapies like PD-1/PD-L1 inhibitors. Also studied in autoimmune and inflammatory disease models to modulate immune cell activity. Serves as a reference standard in bioassay development and antibody characterization.