Fig. 2.

Wildtype and LRRK2^G2019S neurons exhibit robust, inhibitor-insensitive tau pathology. A) Primary hippocampal neurons from NTG or LRRK2^G2019S mice were treated with vehicle or LRRK2 inhibitors at the noted concentrations at 5 DIV. They were further treated with X-T40 tau PFFs at 1.5μg/mL at 7 DIV and fixed and stained for pS202/T205 tau (AT8, magenta) and MAP2 (gray) at 21 DIV. Scale bar = 50μm. B) Quantification of the pS202/T205 tau area normalized to MAP2 area and further normalized to NTG-DMSO-PFF. LRRK2^G2019S neurons showed a small, genotype-level significant reduction in tau pathology, and each genotype showed no tau pathology without addition of X-T40 tau PFFs (Two-way ANOVA; genotype effect ^****p < 0.0001, Dunnett’s multiple comparison test within genotype: NTG: DMSO-PFF vs. DMSO^****p < 0.0001; G2019S: DMSO-PFF vs. DMSO ^****p < 0.0001; All other values were not statistically significant). C) Quantification of the MAP2 area also showed a small genotype-level significant change as well as a reduction related to PFF treatment. Interestingly, the highest dose of PF-360 also elevated MAP2 area slightly (Two-way ANOVA; genotype effect ^***p = 0.001, Dunnett’s multiple comparison test within genotype: NTG: DMSO-PFF vs. 120 nM PF-360-PFF ^**p = 0.0027; G2019S: DMSO-PFF vs. DMSO ^****p < 0.0001; DMSO-PFF vs. 120 nM PF-360 ^*p = 0.0216; All other values were not statistically significant). n (separate cultures) = 7-8 independent samples/group. Data are represented as mean±SEM with individual data points plotted.