Hybrid PET/MRI enables high-spatial resolution, quantitative imaging of amyloid plaques in an Alzheimer‚Äôs disease mouse model
Authors: Georgia R Frost
Thomas Li
Jason Koutcher
Simon Cherry
Yue-Ming Li
Carl Lekaye
Pat Zanzonico
Valerie Longo
Martin Judenhofer
Lauren A Jonas
Journal: Scientific Reports (2020)
Discipline: Multidisciplinary
Keywords: PET probes; amyloid plaques; neurofibrillary tangles; Alzheimer disease; small-animal PET imaging
Affiliations: Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA., Program of Neuroscience, Weill Graduate School of Medical Sciences of Cornell University, New York, NY, 10021, USA., Small Animal Imaging Core Facility, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA., Program of Pharmacology, Weill Graduate School of Medical Sciences of Cornell University, New York, NY, 10021, USA., Department of Biomedical Engineering, University of California, Davis, CA, 95616, USA., Departments of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA., Departments of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA., Departments of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA. ., Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA. ., Program of Neuroscience, Weill Graduate School of Medical Sciences of Cornell University, New York, NY, 10021, USA. ., Program of Pharmacology, Weill Graduate School of Medical Sciences of Cornell University, New York, NY, 10021, USA. .

Abstract:  The emergence of PET probes for amyloid plaques and neurofibrillary tangles, hallmarks of Alzheimer disease (AD), enables monitoring of pathology in AD mouse models. However, small-animal PET imaging is limited by coarse spatial resolution. We have installed a custom-fabricated PET insert into our small-animal MRI instrument and used PET/MRI hybrid imaging to define regions of amyloid vulnerability in 5xFAD mice. We compared fluorine-18 [18F]-Florbetapir uptake in the 5xFAD brain by dedicated small-animal PET/MRI and PET/CT to validate the quantitative measurement of PET/MRI. Next, we used PET/MRI to define uptake in six brain regions. As expected, uptake was comparable to wild-type in the cerebellum and elevated in the cortex and hippocampus, regions implicated in AD. Interestingly, uptake was highest in the thalamus, a region often overlooked in AD studies. Development of small-animal PET/MRI enables tracking of brain region-specific pathology in mouse models, which may prove invaluable to understanding AD progression and therapeutic development. 

Retracted: No

PubPeer comments:
 Figure 3B. 1) WT mice should be devoid of amyloid deposits while this is not the case 2) Figure pannels are duplicated-triplicated between genotypes and brain structures.  , 
 Thank you for bringing this to our attention. We checked our original submission and representative images were correct. Therefore, these duplication must have occurred during the assembly of Figures for publication. We are in the process of correcting this issue. Thanks again. , 
 #2 Dear Dr. Yue-Ming Li, You may also want to check the images used to assemble Figure 1. Both WT and 5xFAD mice in this image seem to be the same mouse.  ,