Figure 7.

In vivo labeling of amyloid deposits in brain sections from an APP23 transgenic mouse (A) and a wild-type mouse (B) with [¹⁸F]BF-168. An autoradiographic study was performed using brain sections at 180 min after intravenous injection of [¹⁸F]BF-168. Numerous hot spots of [¹⁸F]BF-168 can be detected in the cerebral cortex, hippocampus, and entorhinal cortex of transgenic mouse brain (A), in contrast to no apparent uptake in wild-type mouse brain (B). Fluorescences of amyloid deposits appeared after in vitro staining with thioflavin-S in the same section (C). Arrows show amyloid deposits labeled with both [¹⁸F]BF-168 and thioflavin-S, indicating specific labeling of amyloid plaques with intravenously administered [¹⁸F]BF-168. The percentage of areas of [¹⁸F]BF-168 uptake in nine autoradiographic images were significantly correlated with the percentage of areas of in vitro thioflavin-S staining in the same sections (r = 0.923; p < 0.001) (D), suggesting high binding specificity of [¹⁸F]BF-168 to amyloid plaques.