The evolution and genetics of innate immunity

The immune system provides protection from a wide range of pathogens. One c omponent of immunity, the phylogenetically ancient innate immune response, fights infections from the moment of first contact and is the fundamental d efensive weapon of multicellular organisms. The Toll family of receptors ha s a crucial role in immune defence. Studies in fruitflies and in mammals re veal that the defensive strategies of invertebrates and vertebrates are hig hly conserved at the molecular level, which raises the exciting prospects o f an increased understanding of innate immunity.