FIGURE 3.

Exosomal cargo does not induce the accumulation of phosphorylated α-syn in the brains of recipient mice. The sodium dodecyl sulfate (SDS)-soluble fractions of striatum (A) and midbrain (B) of wild-type (wt) mice injected with KO or A53T isolated brain exosomes were examined for the presence of phosphorylated α-syn species using the pS129 antibody. γ-Tubulin was used as a loading control. The fold change between the ipsilateral and contralateral sites in phosphorylated α-syn levels is shown in the graphs. No significant differences in the levels of phosphorylated α-syn species were detected. Data are presented as mean ± SEM of n = 4 animals. Nigral (C) and cortex (D) sections of mice injected with KO or A53T exosomes were stained for phosphorylated α-synuclein and total α-syn, respectively. pS129-positive inclusions were not evident in the ipsilateral tyrosine hydroxylase (TH)-positive neurons of KO- and A53T-injected animals. Labeling with the Syn-1 specific α-syn antibody and neuronal Tuj-1 is showing the absence of endogenous α-syn accumulations. Scale bar, 50 μm. (E) Coronal sections containing the SNpc from mice injected with exosomes from KO and A53T mouse brains were immunolabeled with anti-TH antibody. The numbers of TH-positive neurons were quantified in each section using the ImageJ software (n = 3). Graph shows the% ratio of ipsilateral to contralateral side of TH-positive neurons. Statistical analysis by Student’s t-test did not reveal any statistical differences between the groups.