Common gamma chain cytokines: dissidence in the details.

Cytokines of the common cytokine-receptor gamma-chain (gamma(c)) family are essential for the development and maintenance of lymphocytes. Herein, we will focus on the roles of interleukin-2 (IL-2), IL-7, IL-15 and IL-21, in the orchestration of CD8 T cell responses. Among these cytokines, IL-7 has emerged as a master regulator of survival of immature and mature T lymphocytes, while IL-2, IL-15 and IL-21 appear to have specific functions in T cell homeostasis and differentiation. Hence, the gamma(c) has evolved as an elegant anchor through which related cytokines regulate distinct biological responses in T cells.