[Application of EXODUS system combined with allosteric DNA nanoswitches in the detection of miR-107 among plasma exosomes of Parkinson's disease patients].

This study aimed to achieve rapid detection of Parkinson's disease (PD) plasma exosome miR-107. A case-control design was used to collect ten Parkinson's disease and ten healthy control plasma samples from the Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology from December 2023 to January 2024. Exosome detection via the ultrafast-isolation system (EXODUS) was used to isolate plasma exosomes. The nanoparticle tracking analysis technology and electron microscopy were used to identify exosome particle size and morphology. The Qiagen miRNeasy Micro Kit was used to extract RNA. The microRNA-activated conditional looping of engineered switches (miRacles) was used to detect miR-107, and the relative expression was analyzed by agarose gel electrophoresis. Thermo Fisher RevertAid RT Reverse Transcription Kit was used to perform reverse transcription of RNA, and real-time PCR was used to detect miR-107. The independent samples t-test was used for comparison between groups. EXODUS system completed the isolation of exosomes from 500 μl plasma within 1.5 hours. The exosome concentration (mean±SD) was (4.82±2.02)×10¹⁰ particles/ml in the control group and (5.08±2.34)×10¹⁰ particles/ml in the PD group. There was no significant difference in exosome concentration between PD patients and healthy controls (t=-0.168, P=0.872). The morphology of exosomes was confirmed by electron microscopy. The miRacles nanoswitch could detect fM-level miR-107 and also effectively distinguish miR-107 from its family members, including miR-15a and miR-16. Agarose gel electrophoresis showed that the mean±SD of relative grey value content was 1.00±0.26 in the control group and 1.86±0.21 in the PD group. The miR-107 in the PD group was significantly higher than that in the control (t=-8.143, P<0.001), which was consistent with the result of real-time PCR. EXODUS combined with miRacles could achieve rapid, non-enzymatic and cheap detection of plasma exosomal miR-107 in PD patients.