An increasing number of diseases have being recognized in which misfolded proteins accumulate intracellularly or extracellularly, particularly in diseases of chronic neurodegeneration such as Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease, and prion diseases1. AD is characterized, in part, by the aggregation of amyloid β protein (Aβ) into fibrillar amyloid plaques in selected areas of brain2. Morphological and biochemical characterization of the plaques indicated beta-amyloid proteins Aβ1-40 and Aβ1-42 as their main constituents. Aβ fibrils contain β-sheets structure orientated in parallel and anti-parallel directions, giving rise to a specific arrangement of side chains in self- assemblies, termed cross-strand ladders
