IL-21 is a homodimeric, non-glycosylated polypeptide containing 133 amino acid residues and has a molecular weight of 15.5 kDa. IL-21isa cytokine produced by activated T-cells and can elicit the proliferation of T and B cells and natural killer cells (NK). From recent research, IL-21 has the potential to serve as a target for immunotherapy treatment for treating diseases.
