Abstract
The aggregation and spreading of "tau-seeds" are key for the development and progression of tauopathies, including Alzheimer's disease. Here we describe the steps to isolate and analyze biochemically active tau-seeds from human, mouse, and cell origin. We detail the procedure to isolate soluble tau-seeds by size exclusion chromatography and seeding assay. The isolated tau-seed can be further analyzed to determine the interactome by mass spectrometry. This workflow identifies protein-protein interactors of tau-seeds, providing a useful tool for finding new therapeutic targets. For complete details on the use and execution of this protocol, please refer to Martinez et al.1.