Sterile Inflammation in Drosophila

Figure 1

Tumors appear as damaged tissue, releasing DAMPS including ROS and triggers that recruit hemocytes and activate the proteolytic cascade that results in the production of active Spaetzle (Spz). Spz acts both locally and in the fat body to stimulate signalling through Toll/NFκB. Hemocytes also release the short-range signal TNFα which, along with Toll signalling, activates JNK in the target tissue. JNK signalling produces cytokines like Pvf1, degrades basement membrane via matrix metalloproteases (MMP1), and promotes apoptosis. All these effects tend to recruit and activate further hemocytes at the damage site to generate an effective inflammatory response.