Observation of α-synuclein propagation and pathological structure in human brain organoids by electron microscopy

초록

Aims Late Breaking Abstract Submission Theme C: α-Synucleinopathies / Theme C: α-Synucleinopathies / C07.b. Animal Models: Primates, naturally occuring models and brain organoids Yeojin Kim1, Minkyo Jung1, Min-Kyoung Shin2,3, Junghyun Jo2,3,4, Ji Young Mun1; 1Korea Brain Research Institute, Neural circuits Research group, Daegu, Korea, Republic of, 2Ajou University School of Medicine, Department of Pharmacology, Suwon, Korea, Republic of, 3Ajou University School of Medicine, Center for Convergence Research of Neurological Disorders, Suwon, Korea, Republic of, 4Ajou University School of Medicine, Department of Biomedical Sciences, Suwon, Korea, Republic of The aim of this study was to observe the connectivity of neuron and glia in brain organoids and to investigate the propagation and structural changes of α-synuclein. Methods The sample was first cut into 150 µm thick sections, followed by primary fixation, secondary fixation, and dehydration processes, and then was plasticized with infiltrating resin. The sample was cut into 100 nm sections and mounted on ITO-coated glass, and immunostaining was performed to confirm SNCA expression, and then SEM images were taken. Images were acquired using ZEISS atlas5 software for gemini 300 SEM. Image resolution in the x-y plane was 5nm/pixel. Results The interconnectivity between each cells was validated by SEM images, which also allowed the observation of α-synuclein within each cell by CLEM technique. Furthermore, the structures of Lewy bodies and alpha synuclein aggregates showed different characteristics. (e.g., astrocytes, microglia, and oligodendrocytes). Conclusions In this study, we propose that CLEM technique can be used to analyze wide-area SEM images, resulting in a more detailed examination of the structural changes of α-synuclein and Lewy bodies.