Drosophila melanogaster possesses a sophisticated and effective immune system composed of humoral and cellular immune responses, and production of antimicrobial peptides (AMPs) is an important defense mechanism. Expression of AMPs is regulated by the Toll and IMD (immune deficiency) pathways. Production of AMPs can be systemic in the fat body or a local event in the midgut and epithelium. So far, most studies focus on systemic septic infection in adult flies and little is known about AMP gene activation after ingestion of killed bacteria. In th...