Chapter 14 - Role of TH17 Cells and Interleukin 17 in Graft Versus Host Disease and Graft Versus Leukemia Reactivity

Abstract

The discovery of TH17cells has altered the landscape of immunology and led to numerous studies directed at defining the role that these cells play in inflammatory disorders. Graft versus host disease (GVHD) is one such prototypical inflammatory syndrome that has been thought to be primarily a TH1-mediated process. In this review, we summarize preclinical data derived from experimental murine models that have examined the role of IL-17 and TH17cells in the biology of acute and chronic GVHD. We also examine the role of cytokines (IL-23, IL-6, IL-21) that are either secreted by TH17cells or important for the differentiation and/or maintenance of TH17cells in the biology of experimental GVHD. Finally, we present a review of clinical studies that have utilized single nucleotide polymorphism differences between donor and recipient or the acquisition of patient blood and tissue samples to determine how IL-17 and IL-17-related cytokines impact GVHD severity.