MAPK8 and bacterial infectious disease: Previous studies in the Drosophila midgut showed that ISCs proliferate rapidly to produce new entoerocytes for epithelial renewal, and that homeostasis is maintained by activating JNK, EGFR, JAK/STAT and BMP signalling pathways, which are activated in response to oxidative stress, bacterial infection and ingestion of toxins such as dextran sodium sulfate or bleomycin9, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29.