Functions of IL-15 in anti-viral immunity: multiplicity and variety.
An effective immune response to an invading viral pathogen requires the combined actions of both innate and adaptive immune cells. For example, NK cells and cytotoxic CD8 T cells are capable of the direct engagement of infected cells and the mediation of antiviral responses. Both NK and CD8 T cells depend on common gamma chain (γc) cytokine signals for their development and homeostasis. The γc cytokine IL-15 is very well characterized for its role in promoting the development and homeostasis of NK cells and CD8 T cells, but emerging literature suggests that IL-15 mediates the anti-viral responses of these cell populations during an active immune response. Both NK cells and CD8 T cells must become activated, migrate to sites of infection, survive at those sites, and expand in order to maximally exert effector functions, and IL-15 can modulate each of these processes. This review focuses on the functions of IL-15 in the regulation of multiple aspects of NK and CD8 T cell biology, investigates the mechanisms by which IL-15 may exert such diverse functions, and discusses how these different facets of IL-15 biology may be therapeutically exploited to combat viral diseases.
Department of Cellular Biology, University of Georgia, Athens, GA 30602-2607, USA.
Katherine C
KC
Verbist
Kimberly D
KD
Klonowski
D000818:Animals; D006801:Humans; D007109:Immunity / Q000276:immunology*; D019409:Interleukin-15 / Q000276:immunology*; D008214:Lymphocytes / Q000276:immunology; D014777:Virus Diseases / Q000276:immunology / Q000628:therapy; D014780:Viruses / Q000276:immunology*
D019409:Interleukin-15