An improved method for generating consistent soluble amyloid-beta oligomer preparations for in vitro neurotoxicity studies.

Soluble Abeta oligomers are recognized as playing a key role in Alzheimer's disease (AD) pathophysiology. Despite their significance, many investigators encounter difficulty generating reliable preparations for in vitro and in vivo experiments. Solutions of Abeta are often unstable and soluble conformer profiles inconsistent. In this study we describe detailed methods for preparing Abeta oligomers that are stable for several weeks and are enriched for low and high molecular weight oligomeric forms, including the 56-kDa form, a conformer implicated in AD-related cognitive impairment. We characterize their structural and functional properties using Western blot, dot blot, atomic force microscopy, Thioflavine T fluorescence, and primary neuronal culture toxicity assays. These synthetic preparations should prove valuable to many studying Abeta-mediated mechanisms underlying AD.