(11)C-PBR28 binding to translocator protein increases with progression of Alzheimer's disease.
This longitudinal study sought to determine whether the 18 kDa translocator protein (TSPO), a marker of neuroinflammation, increases over time in Alzheimer's disease. Positron emission tomography imaging with the TSPO radioligand (11)C-PBR28 was performed at baseline and after a median follow-up of 2.7 years in 14 amyloid-positive patients and 8 amyloid-negative controls. Patients had a greater increase in TSPO binding than controls in inferior parietal lobule, precuneus, occipital cortex, hippocampus, entorhinal cortex, and combined middle and inferior temporal cortex. TSPO binding in temporoparietal regions increased from 3.9% to 6.3% per annum in patients, but ranged from -0.5% to 1% per annum in controls. The change in TSPO binding correlated with cognitive worsening on clinical dementia rating scale-sum of boxes and reduced cortical volume. The annual rate of increased TSPO binding in temporoparietal regions was about 5-fold higher in patients with clinical progression (n = 9) compared with those who did not progress (n = 5). TSPO may serve as a biomarker of Alzheimer's progression and response to anti-inflammatory therapies.
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA. Electronic address: wck2107@cumc.columbia.edu.
William C
WC
Kreisl
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
Chul Hyoung
CH
Lyoo
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
Jeih-San
JS
Liow
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
Monica
M
Wei
Office of the Clinical Director, National Institute of Mental Health, Bethesda, MD, USA.
Joseph
J
Snow
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
Emily
E
Page
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
Kimberly J
KJ
Jenko
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
Cheryl L
CL
Morse
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
Sami S
SS
Zoghbi
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
Victor W
VW
Pike
Memory Disorders Program, Georgetown University, Washington, DC, USA.
R Scott
RS
Turner
Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
Robert B
RB
Innis
D000081:Acetamides / Q000378:metabolism*; D000368:Aged; D000544:Alzheimer Disease / Q000000981:diagnostic imaging* / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D001921:Brain / Q000000981:diagnostic imaging*; D002250:Carbon Radioisotopes / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging; D049268:Positron-Emission Tomography; D011485:Protein Binding; D011725:Pyridines / Q000378:metabolism*; D019275:Radiopharmaceuticals / Q000378:metabolism*; D018079:Receptors, GABA / Q000378:metabolism*
D000081:Acetamides; D015415:Biomarkers; D002250:Carbon Radioisotopes; C526798:N-(2-methoxybenzyl)-N-(4-phenoxypyridin-3-yl)acetamide; D011725:Pyridines; D019275:Radiopharmaceuticals; D018079:Receptors, GABA; C499229:TSPO protein, human
Alzheimer's disease; Neuroinflammation; PET imaging