T lymphocytes, a type of white blood cell, play a central role in the regulation of immune responses against infection. The function of T lymphocytes is critically dependent upon their ability to distinguish between self and non-self. The inappropriate recognition of self tissues by T lymphocytes leads to many autoimmune diseases; the most representative systemic autoimmune disease in humans is systemic lupus erythematosus (SLE or lupus). Therapeutic intervention of SLE and other rheumatic diseases requires a better understanding of the molecular and cellular pathways regulating T cell function. Dr. Hongbo Chi is using a new genetic tool to study this molecular pathway in immune responses and autoimmune diseases with the long-term goal of translating the knowledge gained from these studies into innovative therapeutic strategies.