Description
Interleukin-2 is a secreted protein which belongs to the IL-2 family. When environmental substances (molecules or microbes) gain access to the body, these substances (termed antigens) are recognized as foreign by antigen receptors that are expressed on the surface of lymphocytes. Antigen binding to the T cell receptor (TCR) stimulates the secretion of Interleukin-2 / IL-2, and the expression of IL-2 receptors IL-2R