IL-18 as critical co-stimulatory molecules in modulating the immune response of ITAM bearing lymphocytes.

NK cells responses are controlled by inhibitory and activating cell surface receptors. Inhibitory receptors serve to moderate NK activity by dampening cytokine release and cytotoxicity if activating ligands are also triggered by interaction with their receptors on the NK cells. This dampening effect is critical to prevent wide scale self destruction. These studies have focused on cytokine signaling in the context of an environment where ITAM bearing receptors are triggered on NK, NKT and T cells. Our findings indicate that cytokines are an important co-stimulatory signal that is needed to maximize the host innate immune response.