Interleukin-2 (IL-2) is a 15-16 kDa monomeric, α-helical glycoprotein that belongs to the Type I cytokine family. Mouse IL-2 is synthesized as a 169 amino acid (aa) precursor that contains a 20 aa signal sequence and a 149 aa mature chain, and mature mouse IL-2 shares 56% and 73% aa sequence identity with mature human and rat IL-2. IL-2 is part of the body’s natural response to microbial infection, and in discriminating between foreign (“non-self”) and “self”. IL-2 has key roles in key functions of the immune system, tolerance and immunity, primarily via its direct effects on T cells. IL-2 also promotes the differentiation of T cells into effector T cells and into memory T cells when the initial T cells is also stimulated by an antigen, thus helping the body fight off infections.
Monitoring of IL-2 levels in serum provides more detailed insights in several pathological situations such as cancer, infectious diseases, transplant rejection, multiple sclerosis, rheumatoid arthritis, systemic lupus erythematosus and type I diabetes.