Dr. Jonathan Braun's research is focused on the molecular basis of disease-related immune processes. Innate and adaptive immune functions play a major role in susceptibility to and outcome of infectious diseases, autoimmunity and cancer.

Braun's laboratory is devoted to the molecular basis of disease-related immune processes in two areas. Normal intestinal physiology requires peaceful cohabitation of abundant colonic bacteria with the epithelial and immune components of the intestinal mucosa. His laboratory's goals are to understand the cellular and molecular basis of bacterial-immune homeostasis in the gut, and how these insights can explain the pathogenesis and guide the treatment of inflammatory bowel disease. Presently, he and his colleagues are studying the surprising role of intestinal B lymphocytes and CD8 T-cells in prevention of genetic models of mouse colitis, with a focus on their developmental biology and the role of G-coupled and bacterial sensing receptor systems in this process.

Molecules involved in cytotoxic lymphocyte interaction with tumor cells are central to the mechanism and therapeutic strategies of anti-tumor immunity. Braun's current work focuses on the biochemistry and cell biology of the EMP2 subfamily of tetraspan proteins, because of their fundamental role in the intracellular trafficking and surface display of receptors associated with non-caveolin lipid raft domains. His translational research efforts are devoted to immunologic imaging using positron emission tomography (PET) to refine the CTL targeting strategies, and developing early paths to their potential clinical applications.