Evidence for induction of localized amyloid deposits and neuritic plaques by an infectious agent

Abstract

Mice inoculated intracerebrally with mouse brain homogenate infected with a particular strain of scrapie agent developed amyloid and neuritic plaques and amyloid tubercles along the injection track, solid wall-like infiltrations at the injection site, or both, Our observations implicate an infectious agent in the localized formation of the amyloid and the neuritic plaque—the leading pathological change found in normal elderly people and animals and in patients with senile dementia of the Alzheimer type. Further, these studies indicate that microglia appear to play a central role in the pathogenesis of amyloid formation and could be involved in the processing, production, and assembly of the fibers.