Used in immunological research to study T-cell activation and co-stimulatory signaling pathways. Supports the development of therapeutic antibodies and immune checkpoint modulators by serving as a binding target for drug candidates. Commonly employed in ELISA, surface plasmon resonance (SPR), and bioactivity assays to measure ligand-receptor interactions and assess functional properties of Fc-tagged proteins. Facilitates purification steps due to the Fc tag’s affinity for Protein A or G resins. Valuable in preclinical studies involving non-human primate models for evaluating immune responses and safety profiles of biologics.