TSPO and Alzheimer disease: These results are in agreement with numerous previous TSPO PET study in mouse models of AD 26, 29, 51-56 and also the majority of clinical studies 33, 57-59 which reported similar (+10-30%) significant increase in TSPO tracer uptake mostly in regions affected by AD pathology (e.g. hippocampus, frontal and cingulate cortices).