Interleukin-15 (IL-15) is a cytokine with structural similarity to IL-2. Like IL-2, IL-15 binds to and signals through a complex composed of IL-2/IL-15 receptor beta chain (CD122) and the common gamma chain (gamma-C, CD132). IL-15 is secreted by mononuclear phagocytes (among other cells) following infection by virus. This cytokine induces cell proliferation of natural killer cells, which are cells of the innate immune system whose principal role is to kill virally infected cells. IL-15 can stimulate the proliferation of T-lymphocytes. Stimulation by IL-15 occurs following its interaction with IL-15Rα. This interaction may enhance IL-15’s interaction with IL15Rβγc.

> 95% as determined by SDS-PAGE