Fig. 4

Localized inflammatory response to pSyn inclusions in the SNpc is preserved despite CSF1R inhibition. A Major histocompatibility complex II immunoreactive (MHC-IIir) cells in the ipsilateral substantia nigra pars compacta (SNpc) of alpha synuclein preformed fibril (α-syn PFF) or phosphate buffered saline (PBS) injected rats with or without Pexidartinib (PLX3397B) treatment. B Quantification of MHC-IIir microglia in the ipsilateral SNpc demonstrates a significant increase in PFF compared to PBS rats at 2 months that is unaffected by PLX3397B treatment. C–F Ionized calcium-binding adaptor molecule 1 (Iba1, green) and phosphorylated alpha-synuclein at serine 129 (pSyn, red) immunofluorescence in the ipsilateral SNpc 2 months after intrastriatal α-syn PFF or PBS injection, with or without PLX3397B. G Quantification of Iba1 immunoreactivity (Iba1ir) microglia soma size demonstrates a significant increase following α-syn PFF injection as compared to PBS that is unaffected by PLX3397B treatment. Values represent the mean ± SEM. Black outline = no PLX3397B; green outline = PLX3397B; ****p < 0.0001. Scale bars in A and C–F 100 µm