Parkinson’s disease (PD) is a progressive neurodegenerative disease which is histologically characterized by loss of dopaminergic neurons in the substantia nigra and deposition of aggregated alpha‐synuclein (aSyn) in the brain. The detection of aSyn in well accessible fluids has been one of the central approaches in the development of biomarkers for PD. Recently, real‐time quaking‐induced conversion (RT‐QuIC) has been successfully adapted for use with aSyn seeds. Here, we systematically analysed parameters potentially impacting the reliability of this assay by using quantitative real‐time quaking‐induced conversion (qRT‐QuIC) with in vitro‐formed aSyn seeds. Seeds diluted in cerebrospinal fluid (CSF) accelerated the seeding reaction and slightly increased the sensitivity without affecting specificity. Repeated freeze–thaw cycles decreased the apparent lag times of seeds diluted in ddH₂O but did not alter the seeding activity of seeds diluted in CSF. High levels of artificial contamination with blood resulted in prolonged apparent lag times, while sensitivity and specificity were unaffected. Altogether, qRT‐QuIC with aSyn seems to be robust concerning sensitivity and specificity in our model system, but quantitative interpretation might be limited under certain conditions.

中文翻译：

---

通过qRT-QuIC对α-突触核蛋白种子进行高灵敏度检测和定量的潜在干扰源。

帕金森氏病（PD）是一种进行性神经退行性疾病，其组织学特征是黑质中多巴胺能神经元的丢失以及脑中聚集的α-突触核蛋白（aSyn）沉积。在易于获取的液体中检测aSyn已成为开发PD生物标志物的主要方法之一。最近，实时地震诱发的转化（RT-QuIC）已成功地用于aSyn种子。在这里，我们通过使用体外定量实时地震诱导转化（qRT-QuIC）系统分析了可能影响该测定方法可靠性的参数形成aSyn种子。用脑脊髓液（CSF）稀释的种子可加速接种反应，并在不影响特异性的情况下稍微提高敏感性。重复的冻融循环减少了用ddH ₂ O稀释的种子的表观滞后时间，但没有改变用CSF稀释的种子的播种活性。高水平的人工血液污染导致明显的滞后时间延长，而敏感性和特异性不受影响。总的来说，在我们的模型系统中，带有aSyn的qRT-QuIC在敏感性和特异性方面似乎很可靠，但是在某些条件下定量解释可能会受到限制。