β-Interleukin II (44-56)

β-Interleukin II (44-56), (C68H113N19O19) is a peptide with the sequence NH2-ILE-LEU-ASN-GLY-ILE-ASN-ASN-TYR-LYS-ASN-PRO-LYS-LEU-COOH, MW= 1500.7. Interleukin 2 (IL-2) belongs to the interleukin family, a type of cytokine signaling molecule in the immune system, and it is a protein that regulates the activities of the white blood cells (leukocytes, often lymphocytes) responsible for immunity. IL-2, a soluble hormone-like mediator of the immune system, was the first interleukin molecule to be identified and characterized. It is necessary for the growth, proliferation, and differentiation of T cells to become 'effector' T cells. IL-2 is normally produced by T cells during an immune response and is necessary for the development of T cell immunologic memory, which depends upon the expansion of the number and function of antigen-selected T cell clones.IL-2 is also necessary for the maturation of a subset of T cells, termed regulatory T cells, during T cell development in the thymus.

Figure1  Formula of b-Interleukin II (44-56)

Figure2  Structure of Interleukin II 

Ref:

1. Cantrell DA, Smith KA (June 1984). "The interleukin-2 T-cell system: a new cell growth model". Science 224 (4655): 1312–6.

2. Smith KA (May 1988). "Interleukin-2: inception, impact, and implications". Science 240 (4856): 1169–76.

3. Sakaguchi S, Sakaguchi N, Asano M, Itoh M, Toda M (August 1995). "Immunologic self-tolerance maintained by activated T cells expressing IL-2 receptor alpha-chains (CD25). Breakdown of a single mechanism of self-tolerance causes various autoimmune diseases". J. Immunol. 155 (3): 1151–64.

4. ThorntonAM, Shevach EM (July 1998). "CD4+CD25+ immunoregulatory T cells suppress polyclonal T cell activation in vitro by inhibiting interleukin 2 production". J. Exp. Med. 188 (2): 287–96.