TSPO and Alzheimer disease: In vivo studies by others in AD versus control using [11C]-(R)-PK11195 PET to detect TSPO densities in microglia and astrocytes, showed a higher uptake in AD IPC versus healthy control [23] while several other TSPO-targeted studies with the same and other TSPO-specific radiotracers were unable to discern differences between AD and healthy controls in this subregion [24].