Targeting the IL-15 pathway to prevent rejection after organ transplantation

Interleukin 15 regulates a variety of cellular functions, including the actions of dendritic cells, T cells, and natural killer cells. In particular, IL-15 is an important growth and survival factor for natural killer cells, memory cells, and regulatory T cells. After organ transplantation, IL-15 is expressed in acutely and chronically rejected grafts. These IL-15–mediated antidonor responses are inadequately inhibited by most of the currently prescribed immunosuppressive drugs. Therefore, strategies directed toward the IL-15 pathway are warranted; preliminary data on animal transplant models already show that targeting the IL-15 pathway indeed can reduce the incidence of rejection.Agents that block IL-15 action may provide a new perspective for the treatment of allogeneic responses in patients after transplantation.