RT-QuIC-based detection of alpha-synuclein seeding activity in brains of dementia with Lewy Body patients and of a transgenic mouse model of synucleinopathy.

RT-QuIC is a shaking-based cyclic amplification technique originally developed in the prion field to detect minute amounts of scrapie prion protein (PrP). In this study, we applied the RT-QuIC assay to investigate a-synuclein (a-syn) seeding activity in brains of Dementia with Lewy Body (DLB) patients and in brains of G2-3 transgenic mice expressing human a-syn with A53T mutation. The results show that a-syn seeding activity varies between patients with detectable dilutions ranging from 10 to 10 dilutions of brain tissue and is stable under exposures to the cycles of freezing, thawing and sonication. A53T a-syn aggregates from G2-3 transgenic mice greatly favoured A53T recombinant human a-syn as substrates in comparison to wild-type a-syn, suggesting that conformations for wild-type a-syn to be able to adopt are not compatible with that of A53T aggregates from G2-3.