Jay Reddy, MVSc, PhD
Our long-term interest is the cellular and molecular mechanisms underlying the development of human autoimmune diseases. Most healthy humans have a propensity to develop autoimmune diseases, as evidenced by the presence of autoreactive T cells or autoantibodies in their na¯ve periphery. T cells are educated in the thymus, where high-affinity TCR-bearing cells that interact with self-antigens are deleted by negative selection while T cells with low-affinity TCR to self-antigens are selected positively and exported to the periphery. In spite of the high frequency of self-reactive T cells in the naïve peripheral repertoires, autoimmune responses do not ensue spontaneously. How this tolerance is maintained is a fundamental question. We focus our investigations on the role of reactive oxygen species in the maintenance of T cell tolerance and autoimmunity.