Used in immunological research to study T-cell and natural killer (NK) cell activation pathways. Facilitates investigation of immune synapse formation and cell-mediated cytotoxicity by serving as a soluble fusion protein that binds to ligands such as PVR (CD155) and Nectin-2 (CD112). Commonly applied in binding assays, flow cytometry, and functional blocking experiments to modulate immune responses in vitro. Supports development of immunotherapies targeting the CD226 pathway in cancer and autoimmune diseases.