Professor Dr Bruce Beutler

Research focuses: Immune system, innate immunity, receptor proteins, toll gene, toll-like receptors (TLR), tumour necrosis factor (TNF), TNF blockers
Bruce Alan Beutler is an American immunologist and geneticist. In 2011 he was awarded the Nobel Prize in Physiology or Medicine along with Jules Hoffmann and Ralph M. Steinmann. The three scientists researched the human immune system and, as the Nobel committee put it, “revolutionised our understanding of the immune system”. Bruce Beutler and his colleague Jules Hoffmann discovered activation mechanisms of innate immunity. 
All living organisms protect themselves against bacteria and microorganisms with an innate defence system. Beutler and Hoffmann discovered the receptor proteins that recognise such “invaders” when they enter the body and activate the immune system. Dendritic cells, which Steinman discovered, are then involved in the next step in the body’s immune response. Hoffman had recognised the toll gene’s significance for the immune system in flies. Mutations in the toll gene make the body incapable of triggering an effective defence reaction. This is because the gene activates receptor proteins, which in turn set the immune response into motion. Building on this knowledge, Beutler found such receptors, the toll-like receptors (TLRs), in mice. Beutler had thus discovered a new class of immune molecules and proved that the immune reaction is activated via the same mechanism in insects and mammals. These discoveries have contributed significantly to our understanding of diseases and supported the development of new therapies for infections, cancer and inflammatory diseases. 
In earlier research work, Beutler isolated tumour necrosis factor (TNF) in mice and recognised its significance in inflammatory processes. On the one hand, TNF causes tumour cells to die off; on the other hand, it is an important messenger substance for the genesis of inflammatory reactions and fever. Its discovery was the foundation for the development of substances called TNF blockers – medications that prevent the activity of the messenger substance in the immune system in a targeted way and are used in the treatment of autoimmune diseases and rheumatism. At Scripps Research Institute, Beutler developed the world’s largest mutagenesis programme using mice in order to bring about targeted mutations in their DNA.