Used in immunological research to study T-cell activation and co-stimulatory signaling pathways. Serves as a ligand for CD70 in assays evaluating immune cell interactions, particularly in cancer immunotherapy development. Employed in protein-protein interaction studies, ELISA, and surface plasmon resonance (SPR) due to its tagged Fc region, enabling easy detection and immobilization. Also utilized in the development of therapeutic antibodies and biologics targeting the CD27-CD70 axis for autoimmune diseases and oncology.