Used in research and diagnostic applications to study cell adhesion, neural development, and immune cell function. Plays a role in identifying natural killer (NK) cells and certain T-cell subsets in flow cytometry and immunohistochemistry. Supports the development of targeted therapies in oncology, especially in cancers where CD56 is a marker, such as neuroendocrine tumors and some leukemias. The His tag allows for easy purification and detection in recombinant protein studies.