Sections of an AD hippocampus (CA1 region) processed for BChE immunohistochemistry (A,C,E) and over-stained with X-34 (B,D,F) demonstrate several types of extracellular ghost NFT (eNFT; B,D,F) with variable BChE immunoreactivity. BChE immunoreactivity is not discernable in eNFT with fine and cohesive fibrillary structure (A,B) while it is prominent in eNFT with a more coarse and dispersed fibrillary structure (C–F). Asterisks mark positions of the same eNFT in BChE and X-34 preparations. Scale bar = 15 µm.