An extensive network of PHFτ-rich dystrophic neurites permeates neocortex and nearly all neuritic and diffuse amyloid plaques in Alzheimer disease

Abstract

Previous studies demonstrated paired helical filament τ (PHFτ) in neuritic but not diffuse β-amyloid (Aβ) plaques in Alzheimer's disease (AD). Re-examination of amyloid deposits with antibodies to Aβ and PHFτ by conventional and confocal microscopy using double label immunohistochemistry showed that PHFτ is a component of both diffuse and neuritic plaques in AD. Unlike controls, a dense network of PHFτ positive dystrophic neurites extended throughout the AD neocortex permeating nearly all neuritic and diffuse plaques. Thus, PHFτ-rich dystrophic neurites are common components of neuritic and diffuse plaques in AD neocortex.