Mice strain differences in small animal PET [11C]-PiB and [18F]-Florbetaben imaging of {beta}-amyloid plaques

1764 Objectives To investigate the contribution of strain differences on the β-amyloid specific [11C]-PiB and [18F]-Florbetaben ([18F]-FBB) signal in small animal PET. Methods Studies were performed on 22-25mth BRI1-42 (n=6) and APPPS1-21 (n=6) mice, and their respective littermate controls (C57B/6J n=7, B6C3 n=6). To evaluate β-amyloid burden, mice from each strain underwent; a) 60min dynamic scans after an i.v bolus of [11C]-PiB (8.8±0.56MBq, S.A 90.7±1.2 GBq/μmol), and b) 15 or 25min static scans following an i.v injection of [18F]-FBB and an uptake period of 35min (7.5±0.34MBq and 3.9±0.18MBq for APPPS1-21 and BRI1-42 mice respectively, S.A 127.5 ± 67.2 GBq/ μmol). PET data was reconstructed using OSEM2D (4 subsets, 16 iterations). The data was not corrected for attenuation and scatter.Relevant VOI’s were delineated through registration of PET/CT images with a predefined mouse brain VOI template and tracer uptake was quantified through standardized uptake value (SUV). Results Both [11C]-PiB and [18F]-FBB demonstrated significant uptake in APPPS1-21 mice with the highest significance revealed in the hippocampus (p=0.0002 and p Conclusions The strain investigated is of paramount importance to successful β-amyloid imaging.