Anti-viral CD8 T cells and the cytokines that they love

Viral infections cause an immunological disequilibrium that provokes CD8 T cell responses. These cells play critical roles in purging acute infections, limiting persistent infections, and conferring life-long protective immunity. At every stage of the response anti-viral CD8 T cells are sensitive to signals from cytokines. Initially cytokines operate as immunological warning signs that inform of the presence of an infection, and also influence the developmental choices of the responding cells. Later during the course of the response other sets of cytokines support the survival and maintenance of the differentiated anti-viral CD8 T cells. Although many cytokines promote virus-specific CD8 T cells, other cytokines can suppress their activities and thus favor viral persistence. In this review we discuss how select cytokines act to regulate anti-viral CD8 T cells throughout the response and influence the outcome of viral infections.

► CD8 T cells are critical for the control of viral infections.
► Multiple cytokines influence every stage of the anti-viral CD8 T cell response.
► Inflammation and certain γ-chain cytokines enhance effector responses.
► Different classes of γ-chain cytokines promote immunological memory.
► Immunosuppressive cytokines limit CD8 T cell responses and favor viral persistence.