Single-Molecule Counting Coupled to Rapid Amplification Enables Detection of α-Synuclein Aggregates in Cerebrospinal Fluid of Parkinson's Disease Patients

alpha-Synuclein aggregation is a hallmark of Parkinson's disease and a promising biomarker for early detection and assessment of disease progression. The prospect of a molecular test for Parkinson's disease is materializing with the recent developments of detection methods based on amplification of synuclein seeds (e.g. RT-QuIC or PMCA). Here we adapted single-molecule counting methods for the detection of alpha-synuclein aggregates in cerebrospinal fluid (CSF), using a simple 3D printed microscope. Single-molecule methods enable to probe the early events in the amplification process used in RT-QuIC and a precise counting of ThT-positive aggregates. Importantly, the use of single-molecule counting also allows a refined characterization of the samples and fingerprinting of the protein aggregates present in CSF of patients. The fingerprinting of size and reactivity of individual aggregate shows a unique signature for each PD patients compared to controls and may provide new insights on synucleinopathies in the future.

Automated summary

Research on detecting alpha-synuclein aggregates using single-molecule counting methods shows potential for early Parkinson's disease detection and differentiation between patients and controls, with the ability to accurately count aggregates and provide insights for future studies on synucleinopathies.