TLR4 and infection: Indeed, the fruit fly is able to fight most of infections through a variety of immune defenses including the systemic immune response (Toll, IMD, JAK-STAT & JNK pathways), the local immune response (AMP expression & ROS production by barrier epithelia) and the cellular immune response (phagocytosis, opsonization, encapsulation, coagulation and melanization) (45).