Fig. 5
Reliability of RT-QuIC assay for PD biospecimens using different batches of rec-Syn substrate. a RT-QuIC spectra of scalp skin homogenate from a case of neuropathologically confirmed PD or a NS control without any neurological disease using two different batches of rec-Syn substrate (lot 1 and lot 2). Individual traces were means ± SD of ThT fluorescence from the PD skin sample (PD) assayed with rec-Syn lot 1 and lot 2 (n = 6 for both lots) or the control skin sample (Con) assayed with rec-Syn lot 1 (n = 3) and lot 2 (n = 6). b RT-QuIC spectra of SMG homogenate from the same PD and control cases as in a using rec-Syn lot 1 and lot 2. Individual traces were means ± SD of ThT fluorescence from the PD SMG sample (PD) assayed with rec-Syn lot 1 (n = 6) and lot 2 (n = 4) or the control SMG sample (Con) assayed with rec-Syn lot 1 and lot 2 (n = 6 for both lots). c RT-QuIC spectra of sigmoid colon homogenate from the same PD and control cases as in a using rec-Syn lot 1 and lot 2. Individual traces were means ± SD of ThT fluorescence from the PD colon sample (PD) assayed with rec-Syn lot 1 and lot 2 (n = 4 for both lots) or the control colon sample (Con) assayed with rec-Syn lot 1 (n = 5) and lot 2 (n = 4). The dotted line represents the threshold of positivity (11%). The specific batches of rec-Syn substrate used were lot 1 (082517AS) and lot 2 (111317AS) from rPeptide. RT-QuIC assay of skin, SMG, and sigmoid colon specimens was performed using the same protocol as described in Methods, in which 2 µl of tissue homogenates diluted to 10–3 (w/v) was used to seed each reaction