TSPO and schizophrenia: Bloomeld and colleagues39 showed that the binding ratio of the second-generation translocator protein (TSPO) radioligand [11 C] peripheral benzodiazepine receptor 28 (PBR28), a noninvasive measure reflecting the number of activated microglia on brain positron emission tomography (PET), was significantly greater in the GM of patients with schizophrenia and individuals at ultra-high risk of psychosis (i.e., unmedicated individuals with sub-clinical symptoms) than in matched healthy controls.