Novel roles for IL-15 in T cell survival

Interleukin-15 (IL-15) is generally considered to be a regulator of T cell homeostasis because it works with other common gamma-chain cytokines like IL-2 and IL-7 to control the maintenance of naive and memory T cell populations. However, recent reports highlight new roles for IL-15 during the primary immune responses that involve promoting the survival of antigen-specific CD8(+) T cells. These findings illuminate a previously unanticipated role for IL-15 in the generation and resolution of the effector CD8(+) T cell response to pathogens.