Fig. 6.

Differential labeling of NFTs by antibodies to the N- and C-terminal loop domains of PS1. Paraffin sections of hippocampus from a case of sporadic late-onset AD were immunocytochemically labeled with antibodies to phosphorylated tau and PS1. A, Labeling of an NFT with antibody PHF-1 to phosphorylated tau.B, Same region of an adjacent section immunostained with Ab R28 to the PS1 C-terminal loop labels an NFT with similar morphology. C, Section showing several NFTs (arrows) labeled by PS1 Ab R28. D, Section adjacent to the one shown in C immunostained with Ab 231 to the PS1 N terminus shows somatodendritic staining (arrow). NFTs are not labeled.