Used in immunological research to study T cell and B cell activation, particularly in the development of immune responses and regulation of antibody production. Supports the expansion and differentiation of natural killer (NK) cells, making it valuable in cancer immunotherapy studies. Often employed in combination with other cytokines to enhance the efficacy of immune cell therapies. The Fc tag improves stability and enables easy detection and purification, facilitating its use in in vitro and in vivo experimental models. Investigated for potential roles in vaccine development and treatment of chronic infections due to its ability to modulate adaptive immunity.