ITK signalling via the Ras/IRF4 pathway regulates the development and function of Tr1 cells

IL-10+ Tr1 cells, which do not express stable Foxp3 like conventional Treg cells, are associated with various diseases, but little is known about how their differentiation and function are regulated. Here the authors show that ITK is a central TCR signalling effector of the differentiation and function of Tr1 cells.