Ramnik Xavier, M.D, is the Kurt Isselbacher Professor of Medicine at Harvard Medical School, Director of the Center for Computational and Integrative Biology, Core Faculty of the Molecular Biology Department at Massachusetts General Hospital, and Core Institute Member and Co-Director of the Infectious Disease and Microbiome Program at the Broad Institute. Stemming from his initial interest in how Inflammatory Bowel Disease develops, his research programs now integrate novel genetic, molecular, and biochemical approaches to understand gut mucosal homeostasis and inflammation. This has led to a broader interest in the role of intestinal health in human health and disease.
As a clinical gastroenterologist and molecular biologist, Xavier studies the specific molecular mechanisms involved in innate and adaptive immunity as well as the genetic variants associated with Crohn’s disease, ulcerative colitis, and autoimmunity. By determining the physiological functions of inflammatory bowel disease-associated polymorphisms, his work illuminates processes underlying mucosal homeostasis and inflammation. Using human cohorts, the laboratory interrogates the microbiome’s impact on immunity and inflammation. Recent studies demonstrated that microbiome variability influences cytokine production and associated microbiome variation with autoimmunity risk, pinpointing microbial structures likely mediating susceptibility. Through a transformative collaboration with the Broad’s Chemical Biology and Therapeutic Sciences Program, the laboratory aims to discover small molecules that can correct pathways defective in Crohn’s disease and autoimmunity.