PT  - JOURNAL ARTICLE
AU  - Ivan Martinez-Valbuena
AU  - Naomi P. Visanji
AU  - Ain Kim
AU  - Heather H. C. Lau
AU  - Raphaella W. L. So
AU  - Sohaila Alshimemeri
AU  - Andrew Gao
AU  - Michael Seidman
AU  - Maria R. Luquin
AU  - Joel C. Watts
AU  - Anthony E. Lang
AU  - Gabor G. Kovacs
TI  - A novel approach to evaluate alpha-synuclein seeding shows a wide heterogeneity in multiple system atrophy
AID  - 10.1101/2021.08.10.455800
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.08.10.455800
4099  - http://biorxiv.org/content/early/2021/08/10/2021.08.10.455800.short
4100  - http://biorxiv.org/content/early/2021/08/10/2021.08.10.455800.full
AB  - Several in vitro and in vivo findings have consistently shown that α-synuclein derived from multiple system atrophy (MSA) subjects has more seeding capacity than Parkinson’s disease-derived α-synuclein. However, reliable detection of α-synuclein derived from MSA using seeded amplification assays, such as the Real-Time Quaking-induced Conversion, has remained challenging. Here we demonstrate that the interaction of the Thioflavin T dye with α-synuclein from MSA and Parkinson’s disease patients can be modulated by the type of salt, pH, and ionic strength used to generate strain-specific reaction buffers. Employing this novel approach, we have generated a streamlined Real-Time Quaking-induced Conversion assay capable of categorizing MSA brains according to their α-synuclein seeding behavior, and to unravel a previously unrecognized heterogeneity in seeding activity between different brain regions of a given individual that goes beyond immunohistochemical observations and provide a framework for future molecular subtyping of MSA.Competing Interest StatementGGK holds shared patent for the 5G4 antibody. Other authors declare no competing interests.