IL-9 and Th9 cells: Progress and challenges

Abstract

Th9 cells are a new subset of helper T cells, and the signature cytokine for Th9 cells is IL-9. Both Th9 cells and Th9 products are implicated in multiple disease settings. Thus, a clear understanding of how Th9 cells are induced and controlled is an important and clinically relevant issue. There are different molecular pathways identified thus far in the induction of Th9 cells, and activation of such diverse pathways requires integration of signals from TGF-β and IL-4 cytokine receptors as well as costimulatory molecules. These signals converge on the induction of multiple transcription factors that collectively drive the development of Th9 cells. © The Japanese Society for Immunology. 2013. All rights reserved.