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bioRxiv · 10.1101/2023.08.09.552630

Blood-based Nano-QuIC: Accelerated and Inhibitor-resistant Detection of Misfolded Alpha-synuclein

Christenson, P. R.·Jeong, H.·Li, M.·Ahn, H.·Li, D.·Larsen, P. A.·Park, H. Y.·Oh, S.-H.
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Abstract

A hallmark of -synucleinopathies (e.g. Parkinsons disease) is the misfolding and aggregation of -synuclein in tissues and biological fluids. Protein amplification assays like real-time quaking-induced conversion (RT-QuIC) are sensitive yet currently limited to semi-invasive sample types such as cerebrospinal fluid because more accessible samples, such as blood, contain inhibitors. Here, we show that Nanoparticle-enhanced Quaking-induced Conversion (Nano-QuIC) can double the speed of reactions spiked with misfolded -synuclein while increasing sensitivity 100-fold in human plasma. Nano-QuIC detected spike concentrations down to 90 pg/ml in lysed whole blood, while reactions without nanoparticles (RT-QuIC) failed to have any detection due to the presence of strong inhibitors. Moreover, Nano-QuIC showed increased seeding activity in plasma samples from Parkinsons patients (n=4) versus healthy controls (n=4). This sets the groundwork for the noninvasive diagnostic use of Nano-QuIC, potentially enabling early disease detection and management through blood-based testing. TOC graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=104 SRC="FIGDIR/small/552630v2_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@1141573org.highwire.dtl.DTLVardef@18c63d6org.highwire.dtl.DTLVardef@1ee9524org.highwire.dtl.DTLVardef@81af13_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Christenson, P. R., Jeong, H., Li, M., Ahn, H., Li, D., Larsen, P. A., Park, H. Y., Oh, S.-H.. 2023-08-13. Blood-based Nano-QuIC: Accelerated and Inhibitor-resistant Detection of Misfolded Alpha-synuclein. https://doi.org/10.1101/2023.08.09.552630

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