Inflammatory Bowel Disease (IBD) can be a devastating illness. For reasons that are not clear, the cells that line the intestine in patients with IBD mount inappropriate immune responses toward the harmless bacteria that normally inhabit our gastrointestinal tracts. Treatments for IBD therefore involve suppressing immune responses to limit the damage caused by this immune hyperactivation. These medications have many complications, particularly in children who may be more susceptible to the infectious complications associated with their long-term use. The goal of our research is to facilitate the development of new therapies for IBD that specifically limit the hyperactivation of intestinal immune responses. We have identified a novel regulator of inflammatory responses in the cells that line the intestine and in this proposal we explore the mechanism by which this receptor acts to suppress deleterious immune responses. We hypothesize that these discoveries will offer important insights into the pathophysiology of IBD and will suggest a new therapeutic strategy for this disease.