MAPT and Alzheimer disease: The authors reported that in vivo cortical [18F]THK5351 retention correlated not only with postmortem tau immunohistochemistry but also with monoamine oxidase-B (MAO-B) in the whole brain; in addition, MAO-B correlated with glial fibrillary acid protein (GFAP) a marker for astrocytes, and therefore they concluded that [18F]THK5351 PET could be useful to evaluate tau-associated neuroinflammatory states in AD rather than tau pathology.