Figure 3.

Autoradiographic labelling of DNTC temporal cortex sections with ¹¹C-PBB3 and ¹⁸F-AV-1451, followed by histochemical and immunohistochemical microscopic assays. (A) Autoradiographic labelling of subadjacent sections with 5 nM of ¹¹C-PBB3 (left) and ¹⁸F-AV-1451 (right) in the absence (top) and presence (bottom) of 100 µM of non-radioactive PBB5. Bi-layer distribution of ¹⁸F-AV-1451 radiosignals in grey matter are indicated by arrows. (B) GB staining of sections used for autoradiography, along with double labelling of a subadjacent section with AT8 and PBB3 and single labelling of another subadjacent section with AV-1451. GB and AT8 staining in grey matter at low power is compared with corresponding autoradiography with ¹¹C-PBB3 and ¹⁸F-AV-1451 in top panels. Middle and bottom panels depict high-power photomicrographs in middle (1) and superficial (2) grey matter layers, respectively, indicated by the squares in the top panel. Area 1 was enriched with ghost tangles, which were GB-positive, AT8-negative, and were intensely labelled with PBB3 and AV-1451. Area 2 was heavily loaded with neuropil threads, and were clearly stained with PBB3, but only faintly labelled with AV-1451. Scale bars = 200 µm (top in B), 20 µm (middle and bottom in B).