Fig. 2

The development of pαsyn and αsynGFP aggregates in CNP-SNCAGFP Tg mice inoculated with αsyn PFFs. A Image of sonicated αsyn PFFs used for injection in electron microscopy. B The schedule of αsyn PFF injection and histological evaluation. Tg mice (age: 2–3 months) were inoculated with αsyn PFFs or PBS, sacrificed at 1, 4, and 12 mpi, and histological examinations were performed (n = 6). C Immunohistochemical staining for pαsyn at the ipsilateral dorsal striatum of Tg mice inoculated with αsyn PFFs or PBS. In Tg mice, numerous pαsyn-positive neurites were observed as early as 1 mpi, and these thread-like structures grew into round-shaped cytoplasmic inclusions. Only a few pαsyn-positive cells were observed in Tg mice inoculated with PBS. Scale bar = 50 µm. D Fluorescence micrographs of GFP and immunostaining with anti-pαsyn (red) and anti-NeuN (gray) antibodies in the striatum of Tg mice. The merged images include DAPI (blue). Unaggregated αsynGFP is denoted by dotted circles. Most of the pαsyn-positive signals are of neuronal origin (arrowheads), and rarely merged with αsynGFP aggregates (GFP dots) in OLGs (arrows). Scale bar = 20 µm. E Immunofluorescence micrographs of various cellular makers with GFP in Tg mice at 6 mpi of αsyn PFFs. αsynGFP aggregates were observed specifically in the OLGs. The merged images include DAPI (blue). Scale bar = 10 µm. mpi, month(s) post-inoculation; PFFs, preformed fibrils; pαsyn, phosphorylated α-synuclein