Dr Benoist explores how T cells differentiate into their different lineages and final effector states, particularly from the standpoint of self-tolerance and autoimmunity. Studies on autoimmunity explore the molecular and genetic failures of tolerance in diabetes, rheumatoid arthritis and in the disease that appears in Aire-deficient individuals. Major questions tackled are why thymic tolerance is defective in these models, what triggers the autoimmune processes, how their progression is regulated.His research involves a wide range of technologies, including manipulation of the mouse germline, gene expression profiling, mass spectrometry, RNAi screens.