AUTHOR=Metaxas Athanasios , Thygesen Camilla , Briting Sanne R. R. , Landau Anne M. , Darvesh Sultan , Finsen Bente 

TITLE=Increased Inflammation and Unchanged Density of Synaptic Vesicle Glycoprotein 2A (SV2A) in the Postmortem Frontal Cortex of Alzheimer’s Disease Patients

JOURNAL=Frontiers in Cellular Neuroscience

VOLUME=13

YEAR=2019

URL=https://www.frontiersin.org/journals/cellular-neuroscience/articles/10.3389/fncel.2019.00538

DOI=10.3389/fncel.2019.00538

ISSN=1662-5102

ABSTRACT=<p>Sections from the middle frontal gyrus (Brodmann area 46) of autopsy-confirmed Alzheimer’s disease (AD) patients and non-demented subjects were examined for the prevalence of hallmark AD pathology, including amyloid-β (Aβ) plaques, phosphorylated tau (pTau) tangles, neuroinflammation and synaptic loss (<italic>n</italic> = 7 subjects/group). Dense-core deposits of Aβ were present in all AD patients (7/7) and some non-demented subjects (3/7), as evidenced by 6E10 immunohistochemistry. Levels of Aβ immunoreactivity were higher in AD vs. non-AD cases. For pTau, AT8-positive neurofibrillary tangles and threads were exclusively observed in AD patient tissue. Levels of [<sup>3</sup>H]PK11195 binding to the translocator protein (TSPO), a marker of inflammatory processes, were elevated in the gray matter of AD patients compared to non-demented subjects. Levels of [<sup>3</sup>H]UCB-J binding to synaptic vesicle glycoprotein 2A (SV2A), a marker of synaptic density, were not different between groups. In AD patients, pTau immunoreactivity was positively correlated with [<sup>3</sup>H]PK11195, and negatively correlated with [<sup>3</sup>H]UCB-J binding levels. No correlation was observed between Aβ immunoreactivity and markers of neuroinflammation or synaptic density. These data demonstrate a close interplay between tau pathology, inflammation and SV2A density in AD, and provide useful information on the ability of neuroimaging biomarkers to diagnose AD dementia.</p>