Used in research and development of immunotherapies targeting B-cell maturation and survival pathways. Plays a key role in studying plasma cell disorders, including multiple myeloma and other B-cell malignancies. The Fc tag enables detection, purification, and enhanced stability in assays. Commonly used in protein-protein interaction studies, antibody screening, and binding affinity tests. Supports development of therapeutic antibodies and biologics by serving as a recombinant antigen target. Also applied in ELISA, flow cytometry, and surface plasmon resonance (SPR) to evaluate drug candidates targeting the BAFF/APRIL signaling axis.