Bruno Lemaitre obtained his PhD in 1992 with Dario Coen at the University Pierre and Marie Curie (Paris) on the P element transposition in Drosophila. Next, he joined the laboratory of Jules Hoffmann (CNRS, Strasbourg France) as a research associate where he began a genetic dissection of the Drosophila antimicrobial response. One of his initial findings demonstrated that the Toll receptor protein and its downstream signaling pathway are essential components of the fruit fly immune response (Lemaitre et al. (1996) Cell 86:973). This is a pioneer work in innate immunity which facilitated the identification of Toll-like receptors as crucial mediators of human innate immunity. In 1998, he started his own lab at the Centre Génétique Moléculaire a research institute of the Centre National de Recherche Scientifique at Gif-sur-Yvette (France). In 2007, he became professor at the Ecole Polytechnique of Lausanne (EPFL). His laboratory uses the fruit fly as a model genetic system doing research in the field of innate immunity, Drosophila-Spiroplasma interactions and gut homeostasis.