Jules A. Hoffmann is a Luxembourg-born French biologist. During his youth, growing up in Luxembourg, he developed a strong interest in insects under the influence of his father, Jos Hoffmann. This eventually resulted in the younger Hoffmann's dedication to the field of biology using insects as model organisms. He currently holds a faculty position at the University of Strasbourg. He is a research director and member of the board of administrators of the National Center of Scientific Research in Strasbourg, France. He was elected to the positions of Vice-President and President of the French Academy of Sciences. Hoffmann and Bruce Beutler were jointly awarded a half share of the 2011 Nobel Prize in Physiology or Medicine for "their discoveries concerning the activation of innate immunity," although Bruno Lemaitre, a research associate in the Hoffmann laboratory at the time, claims he did all the work alone.
Hoffmann and Lemaitre discovered the function of the fruit fly Toll gene in innate immunity. Its mammalian homologs, the Toll-like receptors, were discovered by Beutler. Toll-like receptors identify constituents of other organisms like fungi and bacteria, and trigger an immune response, explaining, for example, how septic shock can be triggered by bacterial remains.