Nobel Prize for Medicine in 2011
Discovering the genes of immunity: genetics in the service of health
Our immune system is composed of two lines of defence. The first one is constituted by innate immunity, and when microorganisms overcome this line, adaptive immunity intervenes through T and B lymphocytes, that produce antibodies and killer cells able to destroy microorganisms and infected cells.
Once the pathogen is destroyed, the adaptive immune system maintains an immunological memory. The discoveries that have revolutionized the concept of immune defenses have been achieved studying the defense mechanisms of fruit flies (Drosophila melanogaster), with particular reference to the Toll gene family, involved into the embryonic development. These results have demonstrated that fruit flies and mammals use similar molecules in order to activate innate immunity.