TNF and inflammatory bowel disease: [18F]GE-180 targets the translocator protein 18 kDa (tryptophan-rich sensory protein oxygen sensor; TSPO) [67], which is an outer mitochondrial membrane protein that is overexpressed by enterocytes in inflammatory bowel diseases (IBD) [68, 69] as a self-preservation response to tumour necrosis factor (TNF) and interleukin (IL)-8-driven reactive oxygen species (ROS) production and apoptosis [70].