Used in immunological research to study T-cell regulation and immune checkpoint pathways. Supports development of cancer immunotherapies by serving as a target antigen in antibody screening and binding assays. Employed in protein-protein interaction studies to understand B7 family signaling mechanisms. Commonly used in ELISA, surface plasmon resonance (SPR), and flow cytometry due to its tagged format enabling easy detection and immobilization. Facilitates structural and functional studies when expressed in recombinant systems.