$65.00 - $125.00
IL-21 is a cytokine that plays a crucial role in regulating immune responses, particularly affecting natural killer (NK) cells and cytotoxic T cells. It promotes cell proliferation and helps transition from innate to adaptive immunity. IL-21 induces B cells to produce IgG1 and IgG3 and is vital for the generation and maintenance of T follicular helper (Tfh) cells, which are essential for effective antibody responses during viral infections. It works with IL-6 to control early Tfh cell development. Additionally, IL-21 synergizes with IL-15 to enhance NK cell maturation and proliferation and stimulates interferon-gamma production in T cells and NK cells. It may also inhibit dendritic cell activation during T-cell-mediated immune responses.