The IL-17 Family Cytokines in Immunity and Disease

Accumulating evidence suggests that the interleukin (IL)-17 cytokines are major players in the immune response to foreign pathogens. In addition, the pathogeneses of a number of inflammatory diseases have been linked to uncontrolled expression of these cytokine pathways. Genetic and biochemical analyses have elucidated the cellular and molecular events triggered by these proteins during an inflammatory response. While significant efforts have been placed on understanding the functions of IL-17A, IL-17F, and IL-17E, the significance of the other family members, IL-17B-D, in inflammation remains to be determined. This review will focus on the cellular sources, target cell/receptors that are utilized by these cytokines to control pathogenesis, and the therapeutic potential of targeting these pathways to treat inflammatory disorders.