AD pathology is shown in the image below of a hippocampal section stained with the antibody Tau 46.1 and  consists of neurofibrillary tangles (NFT), neuritic plaques (NP), and neuritic threads (arrow). NFTs are pyramidal cells filled with paired helical and straight filaments of aggregated tau, or the extracellular remnants of such left behind after the dissolution of the neuron itself (ghost tangles).  Neuritic plaques are composed of  dystrophic neurites, containing tau aggregates mostly in the straight filament form, surrounding a core of amyloid. Neuronal threads are presumably related to the dystrophic neurites of the plaque, but are not organized into a plaque.